Effects of anthropogenic impacts on benthic macroinvertebrates assemblages in subtropical mountain streams

Directory of Open Access Journals (Sweden)

Leticia M. Mesa

2013-12-01

Full Text Available The nature of the riparian and surrounding landscape has been modified by anthropogenic activities, which may subsequently alter the composition and functional structure of macroinvertebrate assemblages. The effect of these changes on function of benthic fauna is difficult to assess due to the scarce knowledge on functional structures in tropical streams. In this study we evaluate whether sites impacted and unimpacted by anthropogenic alterations differed in assemblage composition and density, richness and diversity of each functional feeding group. The selection of the sites was related to their distinct riparian characteristics, following the QBRy riparian quality index. Collector-gatherer was the dominant functional feeding group, comprising 91% of total density, whereas the proportion of shredders was very low, representing less of 0.5% of total density. Asemblage composition of macroinvertebrates differed between impacted and unimpacted sites. Predators were dominant in taxa number, representing about 60% of total taxa richness. In addition, the diversity and richness of collector-gatherers differed significantly between degraded and unimpacted sites, reflecting the sensitivity of this group to environmental changes and the utility to be used in the assessment of anthropogenic modifications. The results of this study reinforce the idea that riparian corridor management is critical for the distribution of macroinvertebrate assemblages as well as functional organization of lotic streams.

Quantifying Anthropogenic Dust Emissions

Science.gov (United States)

Webb, Nicholas P.; Pierre, Caroline

2018-02-01

Anthropogenic land use and land cover change, including local environmental disturbances, moderate rates of wind-driven soil erosion and dust emission. These human-dust cycle interactions impact ecosystems and agricultural production, air quality, human health, biogeochemical cycles, and climate. While the impacts of land use activities and land management on aeolian processes can be profound, the interactions are often complex and assessments of anthropogenic dust loads at all scales remain highly uncertain. Here, we critically review the drivers of anthropogenic dust emission and current evaluation approaches. We then identify and describe opportunities to: (1) develop new conceptual frameworks and interdisciplinary approaches that draw on ecological state-and-transition models to improve the accuracy and relevance of assessments of anthropogenic dust emissions; (2) improve model fidelity and capacity for change detection to quantify anthropogenic impacts on aeolian processes; and (3) enhance field research and monitoring networks to support dust model applications to evaluate the impacts of disturbance processes on local to global-scale wind erosion and dust emissions.

Nesting habits influence population genetic structure of a bee living in anthropogenic disturbance.

Science.gov (United States)

Vickruck, J L; Richards, M H

2017-05-01

While most organisms are negatively affected by anthropogenic disturbance, a few species thrive in landscapes altered by humans. Typically, native bees are negatively impacted by anthropogenic environmental change, including habitat alteration and climate change. Here, we investigate the population structure of the eastern carpenter bee Xylocopa virginica, a generalist pollinator with a broad geographic range spanning eastern North America. Eastern carpenter bees now nest almost exclusively in artificial wooden structures, linking their geographic distribution and population structure to human activities and disturbance. To investigate the population structure of these bees, we sampled females from 16 different populations from across their range. Nine species-specific microsatellite loci showed that almost all populations are genetically distinct, but with high levels of genetic diversity and low levels of inbreeding overall. Broadly speaking, populations clustered into three distinct genetic groups: a northern group, a western group and a core group. The northern group had low effective population sizes, decreased genetic variability and the highest levels of inbreeding in the data set, suggesting that carpenter bees may be expanding their range northward. The western group was genetically distinct, but lacked signals of a recent range expansion. Climatic data showed that summer and winter temperatures explained a significant amount of the genetic differentiation seen among populations, while precipitation did not. Our results indicate that X. virginica may be one of the rare 'anthrophilic' species that thrive in the face of anthropogenic disturbance. © 2017 John Wiley & Sons Ltd.

Anthropogenic impact on environmental filamentous fungi communities along the Mediterranean littoral.

Science.gov (United States)

Al-Yasiri, Mohammed Hashim; Normand, Anne-Cécile; Mauffrey, Jean-François; Ranque, Stéphane

2017-07-01

We hypothesised that anthropogenic influences impact the filamentous fungi community structure and that particular species or species patterns might serve as markers to characterise ecosystems. This study aimed to describe the filamentous fungi community structure in various biotopes along the Mediterranean shore that were exposed to various levels of anthropogenic influence. We sampled filamentous fungi from yellow-legged gull faecal samples at five study sites along the Mediterranean littoral in southern France. The sites were characterised by variable anthropogenic influence, ranging from building rooftops in two cities to a natural reserve. The sites also included two suburban ecoclines, one of which was exposed to sewer pollution. Filamentous fungal colonies were quantified and identified via MALDI-TOF mass spectrometry. Interestingly, we found that both fungal diversity and abundance were low in urban areas compared with suburban ecocline or environments little affected by anthropogenic influence. Furthermore, some fungal species were clearly associated with particular environments. In particular, Mucor circinelloides was associated with a natural environment with little anthropogenic impact and distant from human settlements. Whereas, Scedosporium apiospermum was associated with an ecocline polluted by sewage. Our findings indicate that particular fungal species or species combination might be used as surrogate markers of ecosystems exposed to anthropogenic pollution. © 2017 Blackwell Verlag GmbH.

[Inventory and environmental impact of VOCs emission from the typical anthropogenic sources in Sichuan province].

Science.gov (United States)

Han, Li; Wang, Xing-Rui; He, Min; Guo, Wei-Guang

2013-12-01

Based on Sichuan province environmental statistical survey data and other relevant activity data, volatile organic compounds (VOCs) emissions from typical anthropogenic sources in Sichuan province were calculated for the year of 2011 by applying the emission factor method. Besides, ozone and secondary organic aerosol formation potentials of these typical anthropogenic sources were discussed. The total VOC emission from these sources was about 482 kt in Sichuan province, biomass burning, solvent utilization, industrial processes, storage and distribution of fuel, and fossil fuel combustion contributed 174 kt, 153 kt, 121 kt, 21 kt and 13 kt, respectively; architecture wall painting, furniture coating, wood decoration painting and artificial board were the major emission sectors of the solvent utilization; while for the industrial processes, 19.4% of VOCs emission was from the wine industry. Chengdu was the largest contributor compared to the other cities in Sichuan, whose VOCs emission from these typical anthropogenic sources in 2011 was 112 kt. OFP of these sources was 1,930 kt altogether. Solvent utilization contributed 50.5% of the total SOA formation potentials, biomass burning and industrial processes both contributed about 23% , with storage and distribution of fuel and fossil fuel combustion accounting for 1% and 1.4%, respectively.

Disentangling the influence of environmental and anthropogenic factors on the distribution of endemic vascular plants in Sardinia.

Science.gov (United States)

Fois, Mauro; Fenu, Giuseppe; Cañadas, Eva Maria; Bacchetta, Gianluigi

2017-01-01

Due to the impelling urgency of plant conservation and the increasing availability of high resolution spatially interpolated (e.g. climate variables) and categorical data (e.g. land cover and vegetation type), many recent studies have examined relationships among plant species distributions and a diversified set of explanatory factors; nevertheless, global and regional patterns of endemic plant richness remain in many cases unexplained. One such pattern is the 294 endemic vascular plant taxa recorded on a 1 km resolution grid on the environmentally heterogeneous island of Sardinia. Sixteen predictors, including topographic, geological, climatic and anthropogenic factors, were used to model local (number of taxa inside each 1 km grid cell) Endemic Vascular Plant Richness (EVPR). Generalized Linear Models were used to evaluate how each factor affected the distribution of local EVPR. Significant relationships with local EVPR and topographic, geological, climatic and anthropogenic factors were found. In particular, elevation explained the larger fraction of variation in endemic richness but other environmental factors (e.g. precipitation seasonality and slope) and human-related factors (e.g. the Human Influence Index (HII) and the proportion of anthropogenic land uses) were, respectively, positively and negatively correlated with local EVPR. Regional EVPR (number of endemic taxa inside each 100 m elevation interval) was also measured to compare local and regional EVPR patterns along the elevation gradient. In contrast to local, regional EVPR tended to decrease with altitude partly due to the decreasing area covered along altitude. The contrasting results between local and regional patterns suggest that local richness increases as a result of increased interspecific aggregation along altitude, whereas regional richness may depend on the interaction between area and altitude. This suggests that the shape and magnitude of the species-area relationship might vary with

Life Cycle Assessment, ExternE and Comprehensive Analysis for an integrated evaluation of the environmental impact of anthropogenic activities

Energy Technology Data Exchange (ETDEWEB)

Pietrapertosa, F.; Cosmi, C. [National Research Council, Institute of Methodologies for Environmental Analysis C.N.R.-I.M.A.A. C.da S.Loja, I-85050 Tito Scalo (PZ) (Italy); National Research Council, National Institute for the Physics of Matter, C.N.R.-I.N.F.M. Via Cinthia, I-80126 Naples (Italy); Macchiato, M. [Federico II University, Department of Physical Sciences, Via Cinthia, I-80126 Naples (Italy); National Research Council, National Institute for the Physics of Matter, C.N.R.-I.N.F.M. Via Cinthia, I-80126 Naples (Italy); Salvia, M.; Cuomo, V. [National Research Council, Institute of Methodologies for Environmental Analysis C.N.R.-I.M.A.A. C.da S.Loja, I-85050 Tito Scalo (PZ) (Italy)

2009-06-15

The implementation of resource management strategies aimed at reducing the impacts of the anthropogenic activities system requires a comprehensive approach to evaluate on the whole the environmental burdens of productive processes and to identify the best recovery strategies from both an environmental and an economic point of view. In this framework, an analytical methodology based on the integration of Life Cycle Assessment (LCA), ExternE and Comprehensive Analysis was developed to perform an in-depth investigation of energy systems. The LCA methodology, largely utilised by the international scientific community for the assessment of the environmental performances of technologies, combined with Comprehensive Analysis allows modelling the overall system of anthropogenic activities, as well as sub-systems, the economic consequences of the whole set of environmental damages. Moreover, internalising external costs into partial equilibrium models, as those utilised by Comprehensive Analysis, can be useful to identify the best paths for implementing technology innovation and strategies aimed to a more sustainable energy supply and use. This paper presents an integrated application of these three methodologies to a local scale case study (the Val D'Agri area in Basilicata, Southern Italy), aimed to better characterise the environmental impacts of the energy system, with particular reference to extraction activities. The innovative methodological approach utilised takes advantage from the strength points of each methodology with an added value coming from their integration as emphasised by the main results obtained by the scenario analysis. (author)

Heterophil/Lymphocyte Alterations as a Measure of Stress in American Alligators in Relation to Anthropogenic Disturbance in a Louisiana Intermediate Marsh

Directory of Open Access Journals (Sweden)

Christopher M. Murray

2015-05-01

Full Text Available Numerous anthropogenic factors represent environmental threats to Gulf Coast wetland ecosystems and associated fauna. American alligators (Alligator mississippiensis have been subject to long-term management and used as ecological and physiological indicators of habitat quality in response to anthropogenic events and stochastic natural disasters. The present study monitored heterophil to lymphocyte ratios (an indicator of stress, in American alligators in a Louisiana intermediate marsh from 2009 to 2011, a time period that coincides with an oil inundation event that occurred in 2011. Sixteen alligators were observed and processed morphometrically (total length, snout-vent length and body mass. Heterophil to lymphocyte ratios were negatively correlated with size, suggesting larger American alligators were physiologically more resilient to the disturbance, more able to actively avoid these poor conditions, or are less affected by localized disturbance.

Natural and anthropogenic {sup 236}U in environmental samples

Energy Technology Data Exchange (ETDEWEB)

Steier, Peter [VERA Laboratory, Fakultaet fuer Physik - Isotopenforschung, Universitaet Wien, Waehringer Strasse 17, A-1090 Wien (Austria)], E-mail: peter.steier@univie.ac.at; Bichler, Max [Atominstitut der Osterreichischen Universitaeten, Technische Universitaet Wien, Stadionallee 2, Wien A-1020 (Austria); Keith Fifield, L. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra, ACT 0200 (Australia); Golser, Robin; Kutschera, Walter; Priller, Alfred [VERA Laboratory, Fakultaet fuer Physik - Isotopenforschung, Universitaet Wien, Waehringer Strasse 17, A-1090 Wien (Austria); Quinto, Francesca [Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, via Vivaldi 43, Caserta 81100 (Italy); Richter, Stephan [Euopean Commission, Directorate-General Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel (Belgium); Srncik, Michaela [Institut fuer Anorganische Chemie, Universitaet Wien, Waehringer Strasse 42, A-1090 Wien (Austria); Terrasi, Philippo [Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, via Vivaldi 43, Caserta 81100 (Italy); Wacker, Lukas [Institute for Particle Physics, HPK H25, Schafmattstrasse 20, CH-8093 Zuerich (Switzerland); Wallner, Anton [VERA Laboratory, Fakultaet fuer Physik - Isotopenforschung, Universitaet Wien, Waehringer Strasse 17, A-1090 Wien (Austria); Wallner, Gabriele [Institut fuer Anorganische Chemie, Universitaet Wien, Waehringer Strasse 42, A-1090 Wien (Austria); Wilcken, Klaus M. [Scottish Universities Environmental Research Centre, Scottish Enterprise Technology Park, East Kilbride G75 OQF (United Kingdom); Maria Wild, Eva [VERA Laboratory, Fakultaet fuer Physik - Isotopenforschung, Universitaet Wien, Waehringer Strasse 17, A-1090 Wien (Austria)

2008-05-15

The interaction of thermal neutrons with {sup 235}U results in fission with a probability of {approx}85% and in the formation of {sup 236}U (t{sub 1/2} = 2.3 x 10{sup 7} yr) with a probability of {approx}15%. While anthropogenic {sup 236}U is, therefore, present in spent nuclear fuel at levels of {sup 236}U/U up to 10{sup -2}, the expected natural ratios in the pre-anthropogenic environment range from 10{sup -14} to 10{sup -10}. At VERA, systematic investigations suggest a detection limit below {sup 236}U/U = 5 x 10{sup -12} for samples of 0.5 mg U, while chemistry blanks of {approx}2 x 10{sup 7} atoms {sup 236}U per sample limit the sensitivity for smaller samples. We have found natural isotopic ratios in uranium reagents separated before the onset of human nuclear activities, in uranium ores from various origins and in water from a subsurface well in Bad Gastein, Austria. Anthropogenic contamination was clearly visible in soil and rivulet samples from Salzburg, Austria, whereas river sediments from Garigliano river (Southern Italy) were close to the detection limit. Finally, our natural in-house standard Vienna-KkU was calibrated against a certified reference material (IRMM REIMEP-18 A)

Migrating mule deer: effects of anthropogenically altered landscapes.

Directory of Open Access Journals (Sweden)

Patrick E Lendrum

Full Text Available Migration is an adaptive strategy that enables animals to enhance resource availability and reduce risk of predation at a broad geographic scale. Ungulate migrations generally occur along traditional routes, many of which have been disrupted by anthropogenic disturbances. Spring migration in ungulates is of particular importance for conservation planning, because it is closely coupled with timing of parturition. The degree to which oil and gas development affects migratory patterns, and whether ungulate migration is sufficiently plastic to compensate for such changes, warrants additional study to better understand this critical conservation issue.We studied timing and synchrony of departure from winter range and arrival to summer range of female mule deer (Odocoileus hemionus in northwestern Colorado, USA, which has one of the largest natural-gas reserves currently under development in North America. We hypothesized that in addition to local weather, plant phenology, and individual life-history characteristics, patterns of spring migration would be modified by disturbances associated with natural-gas extraction. We captured 205 adult female mule deer, equipped them with GPS collars, and observed patterns of spring migration during 2008-2010.Timing of spring migration was related to winter weather (particularly snow depth and access to emerging vegetation, which varied among years, but was highly synchronous across study areas within years. Additionally, timing of migration was influenced by the collective effects of anthropogenic disturbance, rate of travel, distance traveled, and body condition of adult females. Rates of travel were more rapid over shorter migration distances in areas of high natural-gas development resulting in the delayed departure, but early arrival for females migrating in areas with high development compared with less-developed areas. Such shifts in behavior could have consequences for timing of arrival on birthing areas

Diagnostic of ribeirão Mestre d’Armas sub-basin using two methods of rapid environmental assessment, Federal District, Central Brazil

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Julio Cesar Joveli

2010-04-01

Full Text Available Rapid environmental assessments have been used to describe the quality and semi-quantitative attributes of the ecosystems along an environmental gradient using visual observations and few measurements. The aim of this study was to identify and measure anthropogenic impacts on ribeirão Mestre d’Armas sub-basin, Federal District, Central Brazil, and to propose its environmental zoning. This study was performed using two methods based on rapid environmental assessment: a rapid river assessment protocol, to evaluate in an integrated form the features of a lotic system section according to the conservation or degradation condition of the fluvial environment; and the Leopold matrix, to identify and evaluate the anthropogenic impacts. The environmental zoning of this sub-basin detected three areas: preserved, transition and urban areas. The environmental assessment revealed, the preserved area had lotic stretches with natural features under low magnitude of impacts, except on burned areas. In the transition area, there was a predominance of lotic stretches with altered features, due to agriculture and livestock activities of intermediate level of impacts. Finally, the urban area had altered and impacted lotic stretches of higher magnitude due to anthropogenic impacts. Thus, this study revealed large differences among the areas detected by environmental zoning, according to the methods used. These methods were considered complementary in relation to environmental diagnostic of the ribeirão Mestre d’Armas sub-basin.

Anthropogenic protection alters the microbiome in intertidal mangrove wetlands in Hainan Island.

Science.gov (United States)

Yun, Juanli; Deng, Yongcui; Zhang, Hongxun

2017-08-01

Intertidal mangrove wetlands are of great economic and ecological importance. The regular influence of tides has led to the microbial communities in these wetlands differing significantly from those in other habitats. In this study, we investigated the microbiomes of the two largest mangrove wetlands in Hainan Island, China, which have different levels of anthropogenic protection. Soil samples were collected from the root zone of 13 mangrove species. The microbial composition, including key functional groups, was assessed using Illumina sequencing. Bioinformatics analysis showed that there was a significant difference in the microbiomes between the protected Bamen Bay and the unprotected Dongzhai Bay. The overall microbiome was assigned into 78 phyla and Proteobacteria was the most abundant phylum at both sites. In the protected wetland, there were fewer marine-related microbial communities, such as sulfate-reducing bacteria, and more terrestrial-related communities, such as Verrucomicrobia methanotrophs. We also observed distinct microbial compositions among the different mangrove species at the protected site. Our data suggest that the different microbiomes of the two mangrove wetlands are the result of a complex interaction of the different environmental variables at the two sites.

Anthropogenic impacts on the water quality of Aba River, southeast ...

African Journals Online (AJOL)

Anthropogenic impacts on the water quality of Aba River, southeast Nigeria. ... Ethiopian Journal of Environmental Studies and Management ... of Aba River, southeast Nigeria was studied in four stations from November 2014 to August 2015 to identify the major anthropogenic activities and their impact on the water quality.

Climatic impacts of anthropogenic aerosols

Energy Technology Data Exchange (ETDEWEB)

Iversen, T. [Oslo Univ. (Norway)

1996-03-01

This paper was read at the workshop ``The Norwegian Climate and Ozone Research Programme`` held on 11-12 March 1996. Anthropogenic production of aerosols is mainly connected with combustion of fossil fuel. Measured by particulate mass, the anthropogenic sulphate production is the dominating source of aerosols in the Northern Hemisphere. Particles emitted in mechanical processes, fly ash etc. are less important because of their shorter atmospheric residence time. Possible climatological effects of anthropogenic aerosols are usually classified in two groups: direct and indirect. Direct effects are alterations of the radiative heating budget due to the aerosol particles in clear air. Indirect effects involve the interaction between particles and cloud processes. A simplified one-layer radiation model gave cooling in the most polluted mid-latitude areas and heating due to soot absorption in the Arctic. This differential trend in heating rates may have significant effects on atmospheric meridional circulations, which is important for the atmosphere as a thermodynamic system. Recently the description of sulphur chemistry in the hemispheric scale dispersion model has been improved and will be used in a model for Mie scattering and absorption

Natural and anthropogenic radionuclides in the environment

International Nuclear Information System (INIS)

Hille, R.

1984-01-01

A survey is given on the actual knowledge about occurence and environmental relevancy of the most important radionuclides from natural and anthropogenic origin. The contribution of AGF installation is emphasized. (orig.) [de

Status of vulnerable Cystoseira populations along the Italian infralittoral fringe, and relationships with environmental and anthropogenic variables.

Science.gov (United States)

Mancuso, F P; Strain, E M A; Piccioni, E; De Clerck, O; Sarà, G; Airoldi, L

2017-11-03

We analyzed the occurrence and status of infralittoral fringe populations of Cystoseira spp. (Fucales) at thirteen rocky sites around the Italian coastline, and explored the relationships with relevant environmental and anthropogenic variables. We found Cystoseira populations at 11 sites: most were scattered and comprised monospecific stands of C. compressa, and only 6 sites also supported sparse specimens of either C. amentacea var. stricta or C. brachycarpa. Coastal human population density, Chlorophyll a seawater concentrations, sea surface temperature, annual range of sea surface temperature and wave fetch explained most of the variation of the status of C. compressa. We hypothesize a generally unhealthy state of the Italian Cystoseira infralittoral fringe populations and identify multiple co-occurring anthropogenic stressors as the likely drivers of these poor conditions. Extensive baseline monitoring is needed to describe how Cystoseira populations are changing, and implement a management framework for the conservation of these valuable but vulnerable habitats. Copyright © 2017 Elsevier Ltd. All rights reserved.

Risk perception and access to environmental information in four areas in Italy affected by natural or anthropogenic pollution.

Science.gov (United States)

Coi, A; Minichilli, F; Bustaffa, E; Carone, S; Santoro, M; Bianchi, F; Cori, L

2016-10-01

A human biomonitoring (HBM) survey in four areas affected by natural or anthropogenic arsenic pollution was conducted in Italy within the framework of the SEpiAs project. A questionnaire, including the exploration of risk perception (RP) regarding environmental hazards and access to and trust in information, was administered to 282 subjects stratified by area, gender and age. The survey was designed to investigate how populations living in polluted areas could adopt prevention-oriented habits, fostered by the awareness of existing risks and, in addition, how increased knowledge of RP and information flows could support researchers in identifying recommendations, and presenting and disseminating HBM results. This study characterizes the four areas in terms of RP and access to and trust in environmental information, and provides insights into the influence of RP and environmental information on food consumption. For the data analysis, a combined random forest (RF) and logistic regression approach was carried out. RF was applied to the variables derived from the questionnaire in order to identify the most important in terms of the aims defined. Associations were then tested using Fisher's exact test and assessed with logistic regression in order to adjust for confounders. Results showed that the perception of and personal exposure to atmospheric and water pollution, hazardous industries and waste, hazardous material transportation and waste was higher in geographical areas characterized by anthropogenic pollution. Citizens living in industrial areas appeared to be aware of environmental risks and had more confidence in environmental non-governmental organizations (NGOs) than in public authorities. In addition, they reported an insufficient circulation of information. Concerning the influence of RP and environmental information on food consumption, a high perception of personal exposure to atmospheric pollution and hazardous industries was associated with a lower

Effects of climate change and anthropogenic modification on a disturbance-dependent species in a large riverine system

Science.gov (United States)

Zeigler, Sara; Catlin, Daniel H.; Bomberger Brown, M.; Fraser, J.D.; Dinan, Lauren R.; Hunt, Kelsi L.; Jorgensen, Joel G.; Karpanty, Sarah M.

2017-01-01

Humans have altered nearly every natural disturbance regime on the planet through climate and land-use change, and in many instances, these processes may have interacting effects. For example, projected shifts in temperature and precipitation will likely influence disturbance regimes already affected by anthropogenic fire suppression or river impoundments. Understanding how disturbance-dependent species respond to complex and interacting environmental changes is important for conservation efforts. Using field-based demographic and movement rates, we conducted a metapopulation viability analysis for piping plovers (Charadrius melodus), a threatened disturbance-dependent species, along the Missouri and Platte rivers in the Great Plains of North America. Our aim was to better understand current and projected future metapopulation dynamics given that natural disturbances (flooding or high-flow events) have been greatly reduced by river impoundments and that climate change could further alter the disturbance regime. Although metapopulation abundance has been substantially reduced under the current suppressed disturbance regime (high-flow return interval ~ 20 yr), it could grow if the frequency of high-flow events increases as predicted under likely climate change scenarios. We found that a four-year return interval would maximize metapopulation abundance, and all subpopulations in the metapopulation would act as sources at a return interval of 15 yr or less. Regardless of disturbance frequency, the presence of even a small, stable source subpopulation buffered the metapopulation and sustained a low metapopulation extinction risk. Therefore, climate change could have positive effects in ecosystems where disturbances have been anthropogenically suppressed when climatic shifts move disturbance regimes toward more historical patterns. Furthermore, stable source populations, even if unintentionally maintained through anthropogenic activities, may be critical for the

Understanding the Impact of Anthropogenic and Environmental Changes on Dengue Fever Cases in Puerto Rico

Science.gov (United States)

Akanda, A. S.; Serman, E. A.; Couret, J.; Puggioni, G.; Ginsberg, H. S.

2016-12-01

Worldwide, there are an estimated 50-100 million cases of dengue fever each year, roughly 30 times the number of cases as 50 years ago. Dengue was introduced to Puerto Rico (PR) in 1963 and it has experienced epidemic activity ever since. There have been 4 large epidemics since 1990, the most recent in 2010 where almost 27,000 cases were reported. Vaccine development remains in the testing stages, and years away from mass distribution. Effective control thus depends on our understanding of the complex relationships between environmental and anthropogenic factors, mosquito vector ecology, and disease epidemiology. Dengue virus is primarily transmitted by Aedes aegypti mosquitoes, which also carry the Zika virus, and humans in urban environments are their preferred hosts. The purpose of our analysis is to identify trends between anthropogenic and environmental changes and dengue fever cases in PR over the past 15 years. Data on housing and population density, percent impervious surface, and percent tree canopy at the municipality level were procured from the U.S. Census Bureau and the Multi-Resolution Land Characteristics Consortium (MLRC) project, respectively. Land cover data from the National Land Cover Database, created by USGS and NOAA, as well as environmental data from the National Climatic Data Center (NCDC), were also used. Smaller land cover and green space analysis studies have been performed for PR, but this is the first study to consider the island as a whole, and in six distinct regions, with regards to increases in dengue fever cases. The results from this study can be used to understand the effects of urbanization and climate change on vector-borne disease transmission in PR and to project the impact of growing sub-urban and urban areas on dengue cases in coming years. Our results could also be used to assess Dengue and Zika transmission in growing megacites of the world, where urban slums provide a favorable habitat for Ae. aegypti and foster

Anthropogenic impact on biogenic substance distribution and bacterial community in sediment along the Yarlung Tsangpo River on Tibet Plateau, China

Science.gov (United States)

Wang, C.; Peifang, W.; Wang, X.; Hou, J.; Miao, L.

2017-12-01

Lotic river system plays an important part in water-vapor transfer and biogenic substances migration and transformation. Anthropogenic activities, including wastewater discharging and river damming, have altered river ecosystem and continuum. However, as the longest alpine river in China and suffered from increasing anthropogenic activities, the Yarlung Tsangpo River has been rarely studied. Recently, more attention has also been paid to the bacteria in river sediment as they make vital contributions to the biogeochemical nutrient cycling. Here, the distribution of biogenic substances, including nitrogen, phosphorus, silicon and carbon, was explored in both water and sediment of the Yarlung Tsangpo River. By using the next generation 16S rRNA sequencing, the bacterial diversity and structure in river sediment were presented. The results indicated that the nutrient concentrations increased in densely populated sites, revealing that biogenic substance distribution corresponded with the intensity of anthropogenic activity along the river. Nitrogen, phosphorus, silicon and carbon in water and sediment were all retained by the Zangmu Dam which is the only dam in the mainstream of the river. Moreover, the river damming decreased the biomass and diversity of bacteria in sediment, but no significant alteration of community structure was observed upstream and downstream of the dam. The most dominant bacteria all along the river was Proteobacteria. Meanwhile, Verrucomicrobia and Firmicutes also dominated the community composition in upstream and downstream of the river, respectively. In addition, total organic carbon (TOC) was proved to be the most important environmental factor shaping the bacterial community in river sediment. Our study offered the preliminary insights into the biogenic substance distribution and bacterial community in sediment along an alpine river which was affected by anthropogenic activities. In the future, more studies are needed to reveal the

Finding even more anthropogenic indicators in mildly prepared sediment samples

DEFF Research Database (Denmark)

Enevold, Renée; Odgaard, Bent Vad

2016-01-01

be worth the effort to prepare the NPP samples with as mild a preparation method as possible. We have mildly prepared NPP samples from a small forest hollow, Tårup Lund, Denmark. From the recovered NPP assemblages we attempt identifying anthropogenic indicators by comparing to the environmental information......NPPs in anthropogenic soils and archaeological samples are often numerous in types as well as in abundance. Preparing these soil samples with methods based on acid digestion holds the potential of severe bias leaving the NPP assemblages devoid of acid vulnerable NPPs. In many cases it might...... derived from sediment, pollen and macrofossil analyses. The sediment from the forest hollow encompasses environmental information from the last 6000 years, including a period of locally intense pastoral and/or agricultural activity during the Iron Age. Keywords: NPP diversity, forest hollow, anthropogenic...

Anthropogenic chemical cues can alter the swimming behaviour of juvenile stages of a temperate fish.

Science.gov (United States)

Díaz-Gil, Carlos; Cotgrove, Lucy; Smee, Sarah Louise; Simón-Otegui, David; Hinz, Hilmar; Grau, Amalia; Palmer, Miquel; Catalán, Ignacio A

2017-04-01

Human pressure on coastal areas is affecting essential ecosystems including fish nursery habitats. Among these anthropogenic uses, the seasonal increment in the pressure due to leisure activities such as coastal tourism and yachting is an important environmental stressor in many coastal zones. These pressures may elicit understudied impacts due to, for example, sunscreens or other seasonal pollutants. The island of Majorca, northwest Mediterranean Sea, experiences one of the highest number of tourist visits per capita in the world, thus the surrounding coastal habitat is subject to high anthropogenic seasonal stress. Studies on early stages of fishes have observed responses to coastal chemical cues for the selection or avoidance of habitats. However, the potential interferences of human impacts on these signals are largely unknown. A choice chamber was used to determine water type preference and behaviour in naïve settled juvenile gilt-head sea bream (Sparus aurata), a temperate species of commercial interest. Fish were tested individually for behavioural changes with respect to water types from potential beneficial habitats, such as seawater with extract of the endemic seagrass Posidonia oceanica, anthropogenically influenced habitats such as water extracted from a commercial and recreational harbour and seawater mixed with sunscreen at concentrations observed in coastal waters. Using a Bayesian approach, we investigated a) water type preference; b) mean speed; and c) variance in the movement (as an indicator of burst swimming activity, or "sprint" behaviour) as behavioural descriptors with respect to water type. Fish spent similar percentage of time in treatment and control water types. However, movement descriptors showed that fish in sunscreen water moved slower (98.43% probability of being slower) and performed fewer sprints (90.1% probability of having less burst in speed) compared to control water. Less evident increases in sprints were observed in harbour

The extra mile: Ungulate migration distance alters the use of seasonal range and exposure to anthropogenic risk

Science.gov (United States)

Sawyer, Hall; Middleton, Arthur D.; Hayes, Matthew M.; Kauffman, Matthew J.; Monteith, Kevin L.

2016-01-01

Partial migration occurs across a variety of taxa and has important ecological and evolutionary consequences. Among ungulates, studies of partially migratory populations have allowed researchers to compare and contrast performance metrics of migrants versus residents and examine how environmental factors influence the relative abundance of each. Such studies tend to characterize animals discretely as either migratory or resident, but we suggest that variable migration distances within migratory herds are an important and overlooked form of population structure, with potential consequences for animal fitness. We examined whether the variation in individual migration distances (20–264 km) within a single wintering population of mule deer (Odocoileus hemionus) was associated with several critical behavioral attributes of migration, including timing of migration, time allocation to seasonal ranges, and exposure to anthropogenic mortality risks. Both the timing of migration and the amount of time animals allocated to seasonal ranges varied with migration distance. Animals migrating long distances (150–250 km) initiated spring migration more than three weeks before than those migrating moderate (50–150 km) or short distances (forage and effectively increase carrying capacity. Clear differences in winter residency, migration duration, and risk of anthropogenic mortality among short-, moderate-, and long-distance migrants suggest fitness trade-offs may exist among migratory segments of the population. Future studies of partial migration may benefit from expanding comparisons of residents and migrants, to consider how variable migration distances of migrants may influence the costs and benefits of migration.

The green turtle Chelonia mydas as a marine and coastal environmental sentinels: anthropogenic activities and diseases

Directory of Open Access Journals (Sweden)

Isabela Guarnier Domiciano

2017-10-01

Full Text Available The green turtle Chelonia mydas is a widely distributed, slowly maturing species with a complex life cycle, using both oceanic and coastal environments. The species is exposed to different threats and is considered an environmental sentinel that indicates variation among, and the severity of hazards to marine ecosystems. This study aimed to describe both anthropogenic impacts, and infectious and parasitic diseases in C. mydas - including cases along the Brazilian coast - and implications for conservation. Bycatch is reported as the main threat to the conservation of this species, followed by debris ingestion, collisions with boats, dredging, and chronic environmental contamination. All of these impacts may directly or indirectly cause death, by facilitating contact with pathological agents and by increasing vulnerability to secondary diseases. The pathological agents associated with lesions include viruses, bacteria, fungi, protozoa, and helminths. Fibropapillomatosis is an example of a chronic disease characterized by cutaneous and visceral tumors that affects mostly juvenile C. mydas worldwide and is associated with the Chelonid herpesvirus 5. The bacterias Vibrio alginolyticus, Aeromonas hydrophila, and Pseudomonas fluorescens are found in the aquatic environment and among C. mydas lesions in various organs. Trematode adults and eggs of the family Spirorchiidae are also frequent in systemic cardiovascular diseases of C. mydas. The direct impacts of anthropogenic activities and diseases are synergistic and may affect the specie’s health and conservation. Therefore, the monitoring and systematic diagnosing of diseases and causes of death - including necropsy, histopathology, and molecular exams - are necessary to assess a population’s health, to support appropriate decisions of coastal management and to target future research topics that optimize C. mydas conservation.

An investigation of family environmental alteration affecting short-term recovery from Schizophrenia in China.

Science.gov (United States)

Rong-Min Chen, R M

1995-02-01

It has been hypothesised that change in the family environment affects short-term recovery from schizophrenia. Observation and study of 210 schizophrenic patients who were influenced by family environmental alteration show that the prognosis of schizophrenia caused suddenly by family environmental alteration is better than that of schizophrenia caused by a persistently unfavourable family environment. Hence, we think sudden family environmental alterations do not cause psychorrhoea, but slow family environmental alteration may cause change in the mental state of patients. The prognosis is worse in the countryside than in the city. From the study group, we conclude that the first cure rate was 28%, and that 26% of patients were able to work. This indicates that there were no typical cases of the core pattern of schizophrenia, and that there was a certain potential for recovery. In the future, the emphasis of prevention and treatment must be placed on the countryside, and attention should be paid to the improvement of living and working conditions there, to the correct administration of patients, and to the improvement of recovery measures and therapy. We advocate that efforts should be made in the countryside to raise the national educational and cultural level.

Anthropogenic Influences on Estuarine Sedimentation and Ecology: Examples from Varved Sediments of the Pettaquamscutt River Estuary, Rhode Island

Science.gov (United States)

Estuaries and lakes are undergoing anthropogenic alterations as development and industry intensify in the modern world. Assessing the ecological health of such water bodies is difficult because accurate accounts of pre-anthropogenic estuarine/lacustrine conditions do not exist. ...

Anthropogenic Influences on Estuarine Sedimentation and Ecology: Examples from Varved Sediments of the Pettaquanscutt River Estuary, Rhode Island

Science.gov (United States)

Estuaries and lakes are undergoing anthropogenic alterations as development and industry intensify in the modern world. Assessing the ecological health of such water bodies is difficult because accurate accounts of pre-anthropogenic estuarine/lacustrine conditions do not exist. S...

Environmental dissemination of antibiotic resistance genes and correlation to anthropogenic contamination with antibiotics

Science.gov (United States)

Berglund, Björn

2015-01-01

Antibiotic resistance is a growing problem which threatens modern healthcare globally. Resistance has traditionally been viewed as a clinical problem, but recently non-clinical environments have been highlighted as an important factor in the dissemination of antibiotic resistance genes (ARGs). Horizontal gene transfer (HGT) events are likely to be common in aquatic environments; integrons in particular are well suited for mediating environmental dissemination of ARGs. A growing body of evidence suggests that ARGs are ubiquitous in natural environments. Particularly, elevated levels of ARGs and integrons in aquatic environments are correlated to proximity to anthropogenic activities. The source of this increase is likely to be routine discharge of antibiotics and resistance genes, for example, via wastewater or run-off from livestock facilities and agriculture. While very high levels of antibiotic contamination are likely to select for resistant bacteria directly, the role of sub-inhibitory concentrations of antibiotics in environmental antibiotic resistance dissemination remains unclear. In vitro studies have shown that low levels of antibiotics can select for resistant mutants and also facilitate HGT, indicating the need for caution. Overall, it is becoming increasingly clear that the environment plays an important role in dissemination of antibiotic resistance; further studies are needed to elucidate key aspects of this process. Importantly, the levels of environmental antibiotic contamination at which resistant bacteria are selected for and HGT is facilitated at should be determined. This would enable better risk analyses and facilitate measures for preventing dissemination and development of antibiotic resistance in the environment. PMID:26356096

Identification of potential impacts of climate change and anthropogenic activities on streamflow alterations in the Tarim River Basin, China.

Science.gov (United States)

Xue, Lianqing; Yang, Fan; Yang, Changbing; Chen, Xinfang; Zhang, Luochen; Chi, Yixia; Yang, Guang

2017-08-15

Understanding contributions of climate change and human activities to changes in streamflow is important for sustainable management of water resources in an arid area. This study presents quantitative analysis of climatic and anthropogenic factors to streamflow alteration in the Tarim River Basin (TRB) using the double mass curve method (DMC) and the Budyko methods. The time series (1960~2015) are divided into three periods: the prior impacted period (1960~1972) and the two post impacted periods, 1973~1986 and 1987~2015 with trend analysis. Our results suggest that human activities played a dominant role in deduction in the streamflow in TRB with contribution of 144.6% to 120.68% during the post impacted period I and 228.68% to 140.38% during the post impacted period II. Climatic variables accounted for 20.68%~44.6% of the decrease during the post impacted period I and 40.38% ~128.68% during the post impacted period II. Sensitivity analysis indicates that the streamflow alteration was most sensitive to changes in landscape parameters. The aridity index and all the elasticities showed an obvious increasing trend from the upstream to the downstream in the TRB. Our study suggests that it is important to take effective measures for sustainable development of eco-hydrological and socio-economic systems in the TRB.

Environmental enteric dysfunction is associated with altered bile acid metabolism

Science.gov (United States)

Environmental enteric dysfunction (EED), a clinically asymptomatic condition characterized by inflammation of the small bowel mucosa, villous atrophy, and increased gut permeability, is common among children in developing countries. Because of abnormal gut mucosa and altered gut microbiome, EED coul...

Ecological consequences of human niche construction: Examining long-term anthropogenic shaping of global species distributions.

Science.gov (United States)

Boivin, Nicole L; Zeder, Melinda A; Fuller, Dorian Q; Crowther, Alison; Larson, Greger; Erlandson, Jon M; Denham, Tim; Petraglia, Michael D

2016-06-07

The exhibition of increasingly intensive and complex niche construction behaviors through time is a key feature of human evolution, culminating in the advanced capacity for ecosystem engineering exhibited by Homo sapiens A crucial outcome of such behaviors has been the dramatic reshaping of the global biosphere, a transformation whose early origins are increasingly apparent from cumulative archaeological and paleoecological datasets. Such data suggest that, by the Late Pleistocene, humans had begun to engage in activities that have led to alterations in the distributions of a vast array of species across most, if not all, taxonomic groups. Changes to biodiversity have included extinctions, extirpations, and shifts in species composition, diversity, and community structure. We outline key examples of these changes, highlighting findings from the study of new datasets, like ancient DNA (aDNA), stable isotopes, and microfossils, as well as the application of new statistical and computational methods to datasets that have accumulated significantly in recent decades. We focus on four major phases that witnessed broad anthropogenic alterations to biodiversity-the Late Pleistocene global human expansion, the Neolithic spread of agriculture, the era of island colonization, and the emergence of early urbanized societies and commercial networks. Archaeological evidence documents millennia of anthropogenic transformations that have created novel ecosystems around the world. This record has implications for ecological and evolutionary research, conservation strategies, and the maintenance of ecosystem services, pointing to a significant need for broader cross-disciplinary engagement between archaeology and the biological and environmental sciences.

Supplemental feeding alters migration of a temperate ungulate.

Science.gov (United States)

Jones, Jennifer D; Kauffman, Matthew J; Monteith, Kevin L; Scurlock, Brandon M; Albeke, Shannon E; Cross, Paul C

Conservation of migration requires information on behavior and environmental determinants. The spatial distribution of forage resources, which migration exploits, often are altered and may have subtle, unintended consequences. Supplemental feeding is a common management practice, particularly for ungulates in North America and Europe, and carryover effects on behavior of this anthropogenic manipulation of forage are expected in theory, but have received limited empirical evaluation, particularly regarding effects on migration. We used global positioning system (GPS) data to evaluate the influence of winter feeding on migration behavior of 219 adult female elk (Cervus elaphus) from 18 fed ranges and 4 unfed ranges in western Wyoming. Principal component analysis revealed that the migratory behavior of fed and unfed elk differed in distance migrated, and the timing of arrival to, duration on, and departure from summer range. Fed elk migrated 19.2 km less, spent 11 more days on stopover sites, arrived to summer range 5 days later, resided on summer range 26 fewer days, and departed in the autumn 10 days earlier than unfed elk. Time-to-event models indicated that differences in migratory behavior between fed and unfed elk were caused by altered sensitivity to the environmental drivers of migration. In spring, unfed elk migrated following plant green-up closely, whereas fed elk departed the feedground but lingered on transitional range, thereby delaying their arrival to summer range. In autumn, fed elk were more responsive to low temperatures and precipitation events, causing earlier departure from summer range than unfed elk. Overall, supplemental feeding disconnected migration by fed elk from spring green-up and decreased time spent on summer range, thereby reducing access to quality forage. Our findings suggest that ungulate migration can be substantially altered by changes to the spatial distribution of resources, including those of anthropogenic origin, and that

Supplemental feeding alters migration of a temperate ungulate

Science.gov (United States)

Jones, Jennifer D; Kauffman, Matthew J.; Monteith, Kevin L.; Scurlock, Brandon M.; Albeke, Shannon E.; Cross, Paul C.

2014-01-01

Conservation of migration requires information on behavior and environmental determinants. The spatial distribution of forage resources, which migration exploits, often are altered and may have subtle, unintended consequences. Supplemental feeding is a common management practice, particularly for ungulates in North America and Europe, and carryover effects on behavior of this anthropogenic manipulation of forage are expected in theory, but have received limited empirical evaluation, particularly regarding effects on migration. We used global positioning system (GPS) data to evaluate the influence of winter feeding on migration behavior of 219 adult female elk (Cervus elaphus) from 18 fed ranges and 4 unfed ranges in western Wyoming. Principal component analysis revealed that the migratory behavior of fed and unfed elk differed in distance migrated, and the timing of arrival to, duration on, and departure from summer range. Fed elk migrated 19.2 km less, spent 11 more days on stopover sites, arrived to summer range 5 days later, resided on summer range 26 fewer days, and departed in the autumn 10 days earlier than unfed elk. Time-to-event models indicated that differences in migratory behavior between fed and unfed elk were caused by altered sensitivity to the environmental drivers of migration. In spring, unfed elk migrated following plant green-up closely, whereas fed elk departed the feedground but lingered on transitional range, thereby delaying their arrival to summer range. In autumn, fed elk were more responsive to low temperatures and precipitation events, causing earlier departure from summer range than unfed elk. Overall, supplemental feeding disconnected migration by fed elk from spring green-up and decreased time spent on summer range, thereby reducing access to quality forage. Our findings suggest that ungulate migration can be substantially altered by changes to the spatial distribution of resources, including those of anthropogenic origin, and that

Main features of anthropogenic inner-urban soils in Szeged, Hungary

Science.gov (United States)

Puskás, Irén.; Farsang, Andrea

2010-05-01

At the beginning of the 21st century, due to the intensive urbanization it is necessary to gather more and more information on altered physical, chemical and biological parameters of urban soils in order to ensure their suitable management and protection for appropriate living conditions. Nowadays, these measures are very relevant since negative environmental effects can modify the soil forming factors in cities. Szeged, the 4th largest city of Hungary, proved to be an ideal sampling area for the research of urban soils since its original surface has been altered by intensive anthropogenic activities. The main objectives of my research are the investigation, description and evaluation of the altered soils in Szeged. For the physical and chemical analysis (humus, nitrogen, carbonate content, heavy metals, pH, artefacts etc.) of soils 124 samples were taken from the horizons of 25 profiles in Szeged and its peripherals (as control samples). The profiles were sampled at sites affected by different extent of artificial infill according to infill maps (1. profiles fully made up of infill; 2. so-called mixed profiles consisting of considerable amount of infill material and buried soil horizons; 3. natural profiles located in the peripherals of the city). With the help of the above-mentioned parameters, the studied soils of Szeged were assigned into the classification system of WRB(2006), which classifies the soils of urban and industrial areas as an individual soil group (under the term Technosols) for the first time. In accordance with the WRB(2006) nomenclature three main soil types can be identified in Szeged with respect to the degree of human influence: profiles slightly influenced, strongly modified, completely altered by human activities. During this poster, we present the peculiarities of typical urban profiles strongly and completely altered by human influence. Most profiles were placed into the group of Technosols due to the considerable transformation of their

Anthropogenic effects on interaction outcomes: examples from insect-microbial symbioses in forest and savanna ecosystems

DEFF Research Database (Denmark)

Six, Diana L.; Thomas-Poulsen, Michael; Hansen, Allison K.

2011-01-01

The influence of humans on ecosystem dynamics has been, and continues to be, profound. Anthropogenic effects are expected to amplify as human populations continue to increase. Concern over these effects has given rise to a large number of studies focusing on impacts of human activities...... of mutualisms can be to an equally varied set of anthropogenic influences. We also show how alterations of mutualisms may ramify throughout affected systems. We stress that researchers must be cognizant that many observed changes in the behaviors, abundances, and distributions of organisms due to human...... activities are likely to be mediated by mutualists which may alter predictions and actual outcomes in significant ways....

Critical Zone services as environmental assessment criteria in intensively managed landscapes

Science.gov (United States)

Richardson, Meredith; Kumar, Praveen

2017-06-01

The Critical Zone (CZ) includes the biophysical processes occurring from the top of the vegetation canopy to the weathering zone below the groundwater table. CZ services provide a measure for the goods and benefits derived from CZ processes. In intensively managed landscapes, cropland is altered through anthropogenic energy inputs to derive more productivity, as agricultural products, than would be possible under natural conditions. However, the actual costs of alterations to CZ functions within landscape profiles are unknown. Through comparisons of corn feed and corn-based ethanol, we show that valuation of these CZ services in monetary terms provides a more concrete tool for characterizing seemingly abstract environmental damages from agricultural production systems. Multiple models are combined to simulate the movement of nutrients throughout the soil system, enabling the measurement of agricultural anthropogenic impacts to the CZ's regulating services. Results indicate water quality and atmospheric stabilizing services, measured by soil carbon storage, carbon respiration, and nitrate leaching, among others, can cost more than double that of emissions estimated in previous studies. Energy efficiency in addition to environmental impact is assessed to demonstrate how the inclusion of CZ services is necessary in accounting for the entire life cycle of agricultural production systems. These results conclude that feed production systems are more energy efficient and less environmentally costly than corn-based ethanol.

Screening of anthropogenic compounds in polluted sediments and soils

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Leeuw, J.W. de; Leer, E.W.B. de; Schuyl, P.J.W.

1986-01-01

The use of flash evaporation and pyrolysis gas chromatography- mass spectrometry as a fast screening procedure for anthropogenic substances In environmental samples is demonstrated by the analysis of polluted soil and sediment samples. Polycyclic aromatic hydrocarbons, haloorganics,

Influence of Holocene environmental change and anthropogenic impact on the diversity and distribution of roe deer.

Science.gov (United States)

Baker, K H; Hoelzel, A R

2014-06-01

Extant patterns of population structure and levels of diversity are a consequence of factors that vary in both space and time. Our objective in this study is to investigate a species that has responded to both natural and anthropogenic changes in ways that have shaped modern populations and provide insight into the key processes. The roe deer (Capreolus capreolus) is one of the two species of deer native to Britain. During the last glacial maximum (LGM), the British habitat was largely under ice and there was a land bridge to mainland Europe. As the Earth warmed during the early Holocene, the land bridge was lost. Subsequent hunting on the British mainland left the southern region extirpated of roe deer, whereas a refugial population remained in the north. Later reintroductions from Europe led to population expansion, especially in southern United Kingdom. Here, we combine data from ancient and modern DNA to track population dynamics and patterns of connectivity, and test hypotheses about the influence of natural and anthropogenic environmental change. We find that past expansion and divergence events coincided with a warming environment and the subsequent closure of the land bridge between Europe and the United Kingdom. We also find turnover in British roe deer haplotypes between the late-Holocene and modern day that have likely resulted from recent human disturbance activities such as habitat perturbation, overhunting and restocking.

Problems of anthropogenic tritium limitation

Directory of Open Access Journals (Sweden)

Kochetkov О.A.

2013-12-01

Full Text Available This article contains the current situation in respect to the environmental concentrations of anthropogenic and natural tritium. There are presented and analyzed domestic standards for НТО of all Radiation Safety Standards (NRB, as well as the regulations analyzed for tritium in drinking water taken in other countries today. This article deals with the experience of limitation of tritium and focuses on the main problem of rationing of tritium — rationing of organically bound tritium.

Anthropogenic climate change affects meteorological drought risk in Europe

International Nuclear Information System (INIS)

Gudmundsson, L; Seneviratne, S I

2016-01-01

Drought constitutes a significant natural hazard in Europe, impacting societies and ecosystems across the continent. Climate model simulations with increasing greenhouse gas concentrations project increased drought risk in southern Europe, and on the other hand decreased drought risk in the north. Observed changes in water balance components and drought indicators resemble the projected pattern. However, assessments of possible causes of the reported regional changes have so far been inconclusive. Here we investigate whether anthropogenic emissions have altered past and present meteorological (precipitation) drought risk. For doing so we first estimate the magnitude of 20 year return period drought years that would occur without anthropogenic effects on the climate. Subsequently we quantify to which degree the occurrence probability, i.e. the risk, of these years has changed if anthropogenic climate change is accounted for. Both an observational and a climate model-based assessment suggest that it is >95% likely that human emissions have increased the probability of drought years in the Mediterranean, whereas it is >95% likely that the probability of dry years has decreased in northern Europe. In central Europe the evidence is inconclusive. The results highlight that anthropogenic climate change has already increased drought risk in southern Europe, stressing the need to develop efficient mitigation measures. (letter)

Identification of Outlier Loci Responding to Anthropogenic and Natural Selection Pressure in Stream Insects Based on a Self-Organizing Map

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Bin Li

2016-05-01

Full Text Available Water quality maintenance should be considered from an ecological perspective since water is a substrate ingredient in the biogeochemical cycle and is closely linked with ecosystem functioning and services. Addressing the status of live organisms in aquatic ecosystems is a critical issue for appropriate prediction and water quality management. Recently, genetic changes in biological organisms have garnered more attention due to their in-depth expression of environmental stress on aquatic ecosystems in an integrative manner. We demonstrate that genetic diversity would adaptively respond to environmental constraints in this study. We applied a self-organizing map (SOM to characterize complex Amplified Fragment Length Polymorphisms (AFLP of aquatic insects in six streams in Japan with natural and anthropogenic variability. After SOM training, the loci compositions of aquatic insects effectively responded to environmental selection pressure. To measure how important the role of loci compositions was in the population division, we altered the AFLP data by flipping the existence of given loci individual by individual. Subsequently we recognized the cluster change of the individuals with altered data using the trained SOM. Based on SOM recognition of these altered data, we determined the outlier loci (over 90th percentile that showed drastic changes in their belonging clusters (D. Subsequently environmental responsiveness (Ek’ was also calculated to address relationships with outliers in different species. Outlier loci were sensitive to slightly polluted conditions including Chl-a, NH4-N, NOX-N, PO4-P, and SS, and the food material, epilithon. Natural environmental factors such as altitude and sediment additionally showed relationships with outliers in somewhat lower levels. Poly-loci like responsiveness was detected in adapting to environmental constraints. SOM training followed by recognition shed light on developing algorithms de novo to

Re-Occupancy of Breeding Territories by Ferruginous Hawks in Wyoming: Relationships to Environmental and Anthropogenic Factors.

Science.gov (United States)

Wallace, Zachary P; Kennedy, Patricia L; Squires, John R; Oakleaf, Robert J; Olson, Lucretia E; Dugger, Katie M

2016-01-01

Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental factors that influence raptor demographics with re-occupancy of breeding territories by ferruginous hawks (Buteo regalis) across Wyoming, USA, 2011-2013. We also tested correlations of territory re-occupancy with oil and gas infrastructure-a leading cause of habitat modification throughout the range of this species of conservation concern. Probability of re-occupancy was not related to any covariates we investigated in 2011, had a strong negative relationship with cover of sagebrush (Artemisia spp.) in 2012, was slightly higher for territories with artificial platforms than other nest substrates in 2013, and had a positive relationship with abundance of ground squirrels (Urocitellus spp.) that was strong in 2012 and weak in 2013. Associations with roads were weak and varied by year, road-type, and scale: in 2012, re-occupancy probability had a weak positive correlation with density of roads not associated with oil and gas fields at the territory-scale; however, in 2013 re-occupancy had a very weak negative correlation with density of oil and gas field roads near nest sites (≤500 m). Although our results indicate re-occupancy of breeding territories by ferruginous hawks was compatible with densities of anthropogenic infrastructure in our study area, the lack of relationships between oil and gas well density and territory re-occupancy may have occurred because pre-treatment data were unavailable. We used probabilistic sampling at a broad spatial extent, methods to account for imperfect detection, and conducted extensive prey sampling; nonetheless, future research using before

Soil Landscape Pattern Changes in Response to Rural Anthropogenic Activity across Tiaoxi Watershed, China

Science.gov (United States)

Xiao, Rui; Jiang, Diwei; Christakos, George; Fei, Xufeng; Wu, Jiaping

2016-01-01

Soil sealing (loss of soil resources due to extensive land covering for the purpose of house building, road construction etc.) and subsequent soil landscape pattern changes constitute typical environmental problems in many places worldwide. Previous studies concentrated on soil sealing in urbanized regions, whereas rural areas have not been given sufficient attention. Accordingly, this paper studies soil landscape pattern dynamics (i.e., landscape pattern changes in response to rural anthropogenic activities) in the Tiaoxi watershed (Zhejiang province, eastern China), in which surface sealing is by far the predominant component of human forcing with respect to environmental change. A novel approach of quantifying the impacts of rural anthropogenic activities on soil resources is presented. Specifically, quantitative relationships were derived between five soil landscape pattern metrics (patch density, edge density, shape index, Shannon’s diversity index and aggregation index) and three rural anthropogenic activity indicators (anthropogenic activity intensity, distance to towns, and distance to roads) at two landscape block scales (3 and 5 km) between 1985 and 2010. The results showed that the Tiaoxi watershed experienced extensive rural settlement expansion and high rates of soil sealing. Soil landscapes became more fragmented, more irregular, more isolated, and less diverse. Relationships between soil landscape pattern changes and rural anthropogenic activities differed with the scale (spatial and temporal) and variable considered. In particular, the anthropogenic activity intensity was found to be the most important indicator explaining social development intensity, whereas the other two proximity indicators had a significant impact at certain temporal interval. In combination with scale effects, spatial dependency (correlation) was shown to play a key role that should be carefully taken into consideration in any relevant environmental study. Overall, the

Environmental and anthropogenic factors affecting the respiratory toxicity of volcanic ash in vitro

Science.gov (United States)

Tomašek, Ines; Horwell, Claire J.; Damby, David E.; Ayris, Paul M.; Barošová, Hana; Geers, Christoph; Petri-Fink, Alke; Rothen-Rutishauser, Barbara; Clift, Martin J. D.

2016-04-01

Human exposure to inhalable volcanic ash particles following an eruption is a health concern, as respirable-sized particles can potentially contribute towards adverse respiratory health effects, such as the onset or exacerbation of respiratory and cardiovascular diseases. Although there is substantial information on the mineralogical properties of volcanic ash that may influence its biological reactivity, knowledge as to how external factors, such as air pollution, contribute to and augment the potential reactivity is limited. To determine the respiratory effects of volcanic particle interactions with anthropogenic pollution and volcanic gases we will experimentally assess: (i) physicochemical characteristics of volcanic ash relevant to respiratory toxicity; (ii) the effects of simultaneously inhaling anthropogenic pollution (i.e. diesel exhaust particles (DEP)) and volcanic ash (of different origins); (iii) alteration of volcanic ash toxicity following interaction with volcanic gases. In order to gain a first understanding of the biological impact of the respirable fraction of volcanic ash when inhaled with DEP in vitro, we used a sophisticated 3D triple cell co-culture model of the human alveolar epithelial tissue barrier. The multi-cellular system was exposed to DEP [0.02 mg/mL] and then exposed to either a single or repeated dose of well-characterised respirable volcanic ash (0.26 ± 0.09 or 0.89 ± 0.29 μg/cm2, respectively) from the Soufrière Hills volcano, Montserrat for a period of 24 hours using a pseudo-air liquid interface approach. Cultures were subsequently assessed for adverse biological endpoints including cytotoxicity, oxidative stress and (pro)-inflammatory responses. Results indicated that the combination of DEP and respirable volcanic ash at sub-lethal concentrations incited a significant release of pro-inflammatory markers that was greater than the response for either DEP or volcanic ash, independently. Further work is planned, to determine if

Global Anthropogenic Emissions of Non-CO2 Greenhouse Gases 1990-2020

Data.gov (United States)

U.S. Environmental Protection Agency — The data in these Appendices to the Global Anthropogenic Emissions of Non-CO2 Greenhouse Gases (1990-2020) report provide historical and projected estimates of...

Importance of Natural and Anthropogenic Environmental Factors to Fish Communities of the Fox River in Illinois

Science.gov (United States)

Schnier, Spencer; Cai, Ximing; Cao, Yong

2016-02-01

The dominant environmental determinants of aquatic communities have been a persistent topic for many years. Interactions between natural and anthropogenic characteristics within the aquatic environment influence fish communities in complex ways that make the effect of a single characteristic difficult to ascertain. Researchers are faced with the question of how to deal with a large number of variables and complex interrelationships. This study utilized multiple approaches to identify key environmental variables to fish communities of the Fox River Basin in Illinois: Pearson and Spearman correlations, an algorithm based on information theory called mutual information, and a measure of variable importance built into the machine learning algorithm Random Forest. The results are based on a dataset developed for this study, which uses a fish index of biological integrity (IBI) and its ten component metrics as response variables and a range of environmental variables describing geomorphology, stream flow statistics, climate, and both reach-scale and watershed-scale land use as independent variables. Agricultural land use and the magnitude and duration of low flow events were ranked by the algorithms as key factors for the study area. Reach-scale characteristics were dominant for native sunfish, and stream flow metrics were rated highly for native suckers. Regression tree analyses of environmental variables on fish IBI identified breakpoints in percent agricultural land in the watershed (~64 %), duration of low flow pulses (~12 days), and 90-day minimum flow (~0.13 cms). The findings should be useful for building predictive models and design of more effective monitoring systems and restoration plans.

Disentangling Environmental and Anthropogenic Impacts on the Distribution of Unintentionally Introduced Invasive Alien Insects in Mainland China.

Science.gov (United States)

Zhao, Cai-Yun; Li, Jun-Sheng; Xu, Jing; Liu, Xiao-Yan

2017-05-01

Globalization increases the opportunities for unintentionally introduced invasive alien species, especially for insects, and most of these species could damage ecosystems and cause economic loss in China. In this study, we analyzed drivers of the distribution of unintentionally introduced invasive alien insects. Based on the number of unintentionally introduced invasive alien insects and their presence/absence records in each province in mainland China, regression trees were built to elucidate the roles of environmental and anthropogenic factors on the number distribution and similarity of species composition of these insects. Classification and regression trees indicated climatic suitability (the mean temperature in January) and human economic activity (sum of total freight) are primary drivers for the number distribution pattern of unintentionally introduced invasive alien insects at provincial scale, while only environmental factors (the mean January temperature, the annual precipitation and the areas of provinces) significantly affect the similarity of them based on the multivariate regression trees. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

The ecological limits of hydrologic alteration (ELOHA): A new framework for developing regional environmental flow standards

Science.gov (United States)

Poff, N.L.; Richter, B.D.; Arthington, A.H.; Bunn, S.E.; Naiman, R.J.; Kendy, E.; Acreman, M.; Apse, C.; Bledsoe, B.P.; Freeman, Mary C.; Henriksen, J.; Jacobson, R.B.; Kennen, J.G.; Merritt, D.M.; O'Keeffe, J. H.; Olden, J.D.; Rogers, K.; Tharme, R.E.; Warner, A.

2010-01-01

The flow regime is a primary determinant of the structure and function of aquatic and riparian ecosystems for streams and rivers. Hydrologic alteration has impaired riverine ecosystems on a global scale, and the pace and intensity of human development greatly exceeds the ability of scientists to assess the effects on a river-by-river basis. Current scientific understanding of hydrologic controls on riverine ecosystems and experience gained from individual river studies support development of environmental flow standards at the regional scale. 2. This paper presents a consensus view from a group of international scientists on a new framework for assessing environmental flow needs for many streams and rivers simultaneously to foster development and implementation of environmental flow standards at the regional scale. This framework, the ecological limits of hydrologic alteration (ELOHA), is a synthesis of a number of existing hydrologic techniques and environmental flow methods that are currently being used to various degrees and that can support comprehensive regional flow management. The flexible approach allows scientists, water-resource managers and stakeholders to analyse and synthesise available scientific information into ecologically based and socially acceptable goals and standards for management of environmental flows. 3. The ELOHA framework includes the synthesis of existing hydrologic and ecological databases from many rivers within a user-defined region to develop scientifically defensible and empirically testable relationships between flow alteration and ecological responses. These relationships serve as the basis for the societally driven process of developing regional flow standards. This is to be achieved by first using hydrologic modelling to build a 'hydrologic foundation' of baseline and current hydrographs for stream and river segments throughout the region. Second, using a set of ecologically relevant flow variables, river segments within the

Benthic polychaetes in the Ratnagiri bay, India: Influence of anthropogenic factors

Digital Repository Service at National Institute of Oceanography (India)

Sukumaran, S.; Bhokepode, K.; Telavane, M.; Kubal, P.; Gajbhiye, S.N.

Study of changes in macrobenthic community structure is an intrinsic part of many environmental monitoring programmes. Hence, it is pivotal to distinguish the effects of natural and anthropogenic factors on these sensitive organisms for accurate...

Celtic field agriculture and Early Anthropogenic Environmental change in the Meuse-Demer-Scheldt region, NW Europe

Science.gov (United States)

Van der Sanden, Germaine; Kluiving, Sjoerd; Roymans, Nico

2016-04-01

The field of Archaeology remains focused on historical issues while underexploring its potential contribution on currently existing societal problems, e.g. climate change. The aim of this paper is to show the relevance of archeological studies for the research of the 'human species as a significant moving agent' in terms of the changing natural environment during a much earlier time frame. This research is based on the study area of the Meuse-Demer-Scheldt region in the Netherlands and Belgium and exhibits the period from the Late Bronze Age to the Early Roman period. This period is characterized by the widespread introduction and use of an agricultural system, often referred to as the Celtic Field system that served as one of the most modifying systems in terms of anthropogenic-environmental change during this period. Emphasis in this research is given to results generated by the use of the remote sensing technology, LiDAR. New information is reported considering a correlation between singular field size and the overall surface of the agricultural complexes and secondly, the presentation of newly identified Celtic field systems in the Meuse-Demer-Scheldt region are presented. The study of the dynamics of the Celtic Field agricultural system provides evidence for a significant anthropogenic footprint on the natural environment due to land cover dominance, soil degeneration, increased soil acidification and forest clearance. Soil exhaustion forced the inhabitants to re-establish their relationship with the landscape in terms of fundamental changes in the habitation pattern and the agrarian exploitations of the land.

Environmental contaminants and microRNA regulation: Transcription factors as regulators of toxicant-altered microRNA expression

Energy Technology Data Exchange (ETDEWEB)

Sollome, James; Martin, Elizabeth [Department of Environmental Science & Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (United States); Sethupathy, Praveen [Department of Genetics, School of Medicine, University of North Carolina, Chapel Hill, NC (United States); Fry, Rebecca C., E-mail: rfry@unc.edu [Department of Environmental Science & Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill (United States); Curriculum in Toxicology, School of Medicine, University of North Carolina, Chapel Hill, NC (United States)

2016-12-01

MicroRNAs (miRNAs) regulate gene expression by binding mRNA and inhibiting translation and/or inducing degradation of the associated transcripts. Expression levels of miRNAs have been shown to be altered in response to environmental toxicants, thus impacting cellular function and influencing disease risk. Transcription factors (TFs) are known to be altered in response to environmental toxicants and play a critical role in the regulation of miRNA expression. To date, environmentally-responsive TFs that are important for regulating miRNAs remain understudied. In a state-of-the-art analysis, we utilized an in silico bioinformatic approach to characterize potential transcriptional regulators of environmentally-responsive miRNAs. Using the miRStart database, genomic sequences of promoter regions for all available human miRNAs (n = 847) were identified and promoter regions were defined as − 1000/+500 base pairs from the transcription start site. Subsequently, the promoter region sequences of environmentally-responsive miRNAs (n = 128) were analyzed using enrichment analysis to determine overrepresented TF binding sites (TFBS). While most (56/73) TFs differed across environmental contaminants, a set of 17 TFs was enriched for promoter binding among miRNAs responsive to numerous environmental contaminants. Of these, one TF was common to miRNAs altered by the majority of environmental contaminants, namely SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 3 (SMARCA3). These identified TFs represent candidate common transcriptional regulators of miRNAs perturbed by environmental toxicants. - Highlights: • Transcription factors that regulate environmentally-modulated miRNA expression are understudied • Transcription factor binding sites (TFBS) located within DNA promoter regions of miRNAs were identified. • Specific transcription factors may serve as master regulators of environmentally-mediated microRNA expression.

Environmental contaminants and microRNA regulation: Transcription factors as regulators of toxicant-altered microRNA expression

International Nuclear Information System (INIS)

Sollome, James; Martin, Elizabeth; Sethupathy, Praveen; Fry, Rebecca C.

2016-01-01

MicroRNAs (miRNAs) regulate gene expression by binding mRNA and inhibiting translation and/or inducing degradation of the associated transcripts. Expression levels of miRNAs have been shown to be altered in response to environmental toxicants, thus impacting cellular function and influencing disease risk. Transcription factors (TFs) are known to be altered in response to environmental toxicants and play a critical role in the regulation of miRNA expression. To date, environmentally-responsive TFs that are important for regulating miRNAs remain understudied. In a state-of-the-art analysis, we utilized an in silico bioinformatic approach to characterize potential transcriptional regulators of environmentally-responsive miRNAs. Using the miRStart database, genomic sequences of promoter regions for all available human miRNAs (n = 847) were identified and promoter regions were defined as − 1000/+500 base pairs from the transcription start site. Subsequently, the promoter region sequences of environmentally-responsive miRNAs (n = 128) were analyzed using enrichment analysis to determine overrepresented TF binding sites (TFBS). While most (56/73) TFs differed across environmental contaminants, a set of 17 TFs was enriched for promoter binding among miRNAs responsive to numerous environmental contaminants. Of these, one TF was common to miRNAs altered by the majority of environmental contaminants, namely SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 3 (SMARCA3). These identified TFs represent candidate common transcriptional regulators of miRNAs perturbed by environmental toxicants. - Highlights: • Transcription factors that regulate environmentally-modulated miRNA expression are understudied • Transcription factor binding sites (TFBS) located within DNA promoter regions of miRNAs were identified. • Specific transcription factors may serve as master regulators of environmentally-mediated microRNA expression

Impact of anthropogenic and natural environmental changes on Echinococcus transmission in Ningxia Hui Autonomous Region, the People's Republic of China.

Science.gov (United States)

Yang, Yu Rong; Clements, Archie C A; Gray, Darren J; Atkinson, Jo-An M; Williams, Gail M; Barnes, Tamsin S; McManus, Donald P

2012-07-24

Echinococcus transmission is known to be affected by various environmental factors, which may be modified by human influence or natural events including global warming. Considerable population growth in the last fifty years in Ningxia Hui Autonomous Region (NHAR), the People's Republic of China (PRC), has led to dramatic increases in deforestation and modified agricultural practices. In turn, this has resulted in many changes in the habitats for the definitive and intermediate hosts of both Echinococcus granulosus and E. multilocularis, which have increased the risks for transmission of both parasites, affecting echinococcosis prevalence and human disease. Ecological environmental changes due to anthropogenic activities and natural events drive Echinococcus transmission and NHAR provides a notable example illustrating how human activity can impact on a parasitic infection of major public health significance. It is very important to continually monitor these environmental (including climatic) factors that drive the distribution of Echinococcus spp. and their impact on transmission to humans because such information is necessary to formulate reliable future public health policy for echinococcosis control programs and to prevent disease spread.

Benchmarking Anthropogenic Heavy Metals Emissions: Australian and Global Urban Environmental Health Risk Based Indicators of Sustainability

Science.gov (United States)

Dejkovski, Nick

2016-01-01

In Australia, the impacts of urbanisation and human activity are evident in increased waste generation and the emissions of metals into the air, land or water. Metals that have accumulated in urban soils almost exclusively anthropogenically can persist for long periods in the environment. Anthropogenic waste emissions containing heavy metals are a…

Sustainability and the anthropogenic alteration of evolutionary processes

Directory of Open Access Journals (Sweden)

John Cairns, Jr.

2004-08-01

Full Text Available Persuasive evidence indicates that Earth is now experiencing a major biotic crisis. Even if humankind ceases severe stress on natural systems, the crisis will probably disrupt the basic evolutionary processes that characterized the period preceding the agricultural and industrial revolutions.Proliferation of drug and pesticide resistant species and opportunistic species that thrive in human-dominated ecosystems will become increasingly common. The effect on humankind of altering basic evolutionary processes is uncertain because the understanding of these processes is not robust. The probable result will not be an environment as favorable to humans as the one that has existed for most of human history. Humans probably have altered the environment since Homo sapiens first appeared. However, only in the last two centuries has the degree and rate of change reached levels now considered by many people to be ‘normal’, even though the record shows they are not.Greatly improved technology has facilitated increased exploitation of natural resources to unsustainablelevels. This exploitation, in turn, has led to exponential human population growth, which has depleted natural capital (living systems and the services they provide. Economic globalization has ensured that ecosystems far distant from consumers can be and are profitably exploited. Economicgrowth has become a universal mantra that is coupled with a conviction that such growth can continue indefinitely on a finite planet. A major paradigm shift is essential if sustainable use of the planet is to become a reality.

Effect of environmental factors (wave exposure and depth) and anthropogenic pressure in the C sink capacity of Posidonia oceanica meadows

KAUST Repository

Mazarrasa, Iné s; Marbà , Nú ria; Garcia-Orellana, Jordi; Masqué , Pere; Arias-Ortiz, Ariane; Duarte, Carlos M.

2017-01-01

Seagrass are among the most important natural carbon sinks on Earth with Posidonia oceanica (Mediterranean Sea) considered as the most relevant species. Yet, the number of direct measurements of organic carbon burial rates in P. oceanica is still scarce and the effect of local environmental factors remains largely unexplored. In addition, P. oceanica meadows are declining due to the increase in anthropogenic pressure in coastal areas during the last century. The aim of this study is to assess the recent carbon sink capacity of P. oceanica and particularly the effect of human pressure and two environmental factors, water depth and exposure to wave energy (based on a fetch index), on the carbon burial rate since 1900. We conducted an extensive survey of sediment cores in meadows distributed across a gradient of depth, fetch, and human pressure around The Balearic Islands. Sediment and carbon accumulation rates were obtained from 210Pb concentrations profiles. Top-30 centimeters carbon stocks (6.1 ± 1.4 kg C m−2) and burial rates (26 ± 6 g C m−2 yr1) varied up to fivefold across meadows. No significant effect of water depth in carbon burial rates was observed. Although fetch was significantly correlated with sediment mean grain size, confirming the effect of wave exposure in the patterns of sedimentation, fetch alone could not explain the differences in carbon burial rates among the meadows examined. Human pressure affected carbon burial rates, leading to increased rates since the onset of the rise in anthropogenic pressure, particularly so in sheltered meadows supporting high human pressure.

Effect of environmental factors (wave exposure and depth) and anthropogenic pressure in the C sink capacity of Posidonia oceanica meadows

KAUST Repository

Mazarrasa, Inés

2017-03-20

Seagrass are among the most important natural carbon sinks on Earth with Posidonia oceanica (Mediterranean Sea) considered as the most relevant species. Yet, the number of direct measurements of organic carbon burial rates in P. oceanica is still scarce and the effect of local environmental factors remains largely unexplored. In addition, P. oceanica meadows are declining due to the increase in anthropogenic pressure in coastal areas during the last century. The aim of this study is to assess the recent carbon sink capacity of P. oceanica and particularly the effect of human pressure and two environmental factors, water depth and exposure to wave energy (based on a fetch index), on the carbon burial rate since 1900. We conducted an extensive survey of sediment cores in meadows distributed across a gradient of depth, fetch, and human pressure around The Balearic Islands. Sediment and carbon accumulation rates were obtained from 210Pb concentrations profiles. Top-30 centimeters carbon stocks (6.1 ± 1.4 kg C m−2) and burial rates (26 ± 6 g C m−2 yr1) varied up to fivefold across meadows. No significant effect of water depth in carbon burial rates was observed. Although fetch was significantly correlated with sediment mean grain size, confirming the effect of wave exposure in the patterns of sedimentation, fetch alone could not explain the differences in carbon burial rates among the meadows examined. Human pressure affected carbon burial rates, leading to increased rates since the onset of the rise in anthropogenic pressure, particularly so in sheltered meadows supporting high human pressure.

Dynamic soil properties in response to anthropogenic disturbance

Science.gov (United States)

Vanacker, Veerle; Ortega, Raúl

2013-04-01

Anthropogenic disturbance of natural vegetation can profoundly alter the physical, chemical and biological processes within soils. Rapid removal of topsoil during intense farming can result in an imbalance between soil production through chemical weathering and physical erosion, with direct implications on local biogeochemical cycling. However, the feedbacks between soil erosion, chemical weathering and biogeochemical cycling in response to anthropogenic forcing are not yet fully understood. Here, we study dynamic soil properties for a rapidly changing anthropogenic landscape, and focus on the coupling between physical erosion, soil production and soil chemical weathering. The archaeological site of Santa Maria de Melque (Toledo, Central Spain) was selected for its remarkably long occupation history dating back to the 7th century AD. As part of the agricultural complex, four retention reservoirs were built in the Early Middle Ages. The sedimentary archive was used to track the evolution in sedimentation rates and geochemical properties of the sediment. Catchment-wide soil erosion rates vary slightly between the various occupation phases (7th century-now), but are of the same magnitude as the cosmogenic nuclide-derived erosion rates. However, there exists large spatial variation in physical erosion rates that are coupled with chemical weathering intensities. The sedimentary records suggest that there are important changes in the spatial pattern of sediment source areas through time as a result of changing land use patterns

DEPENDENCE OF GRASS COVER TAXONOMIC AND ECOLOGICAL STRUCTURE ON THE ANTHROPOGENIC IMPACT IN FOREST ECOSYSTEMS

Directory of Open Access Journals (Sweden)

N. V. Miroshnik

2016-01-01

Full Text Available Pine forests Chigirinsky Bor grow on fresh sod-podzolic soils formed on ancient alluvial deposits. Pine forests are characterized by stringent moisture regimes and constantly suffer from lack of productive moisture in soil.  Industrial development of Cherkasy in 60th years of ХХ century leaded air pollution and emissions of SO2, NOx, NH3, and dust. This contributed to significant negative influence on the surrounding forest ecosystems from enterprises of  Cherkassy industrial agglomeration. The grass cover in pine stands of Chigirinsky Bor transforms into xerophytic grasses and ruderal communities under the impact of negative biotic and abiotic factors. They are namely the anthropogenic violation of forest conditions, stands decline, recreational and industrial tree crowns understocking, xerophytic and heliophytic transformations of forest conditions. All the above mentioned caused strong ruderal and adventive transformation of grass cover. We registered the changes in nitrophilous plant spread regards the Cherkasy industrial agglomeration approaching which emits toxic with nitrogen-containing gases. Adventive and other non-forest species displace ferns and mosses, the ratio of ecomorfs is also changes due to increase of the quantity and development activation of annuals, xerophytic, ruderal, and nitrofil plants. The Asteraceae/Brassicaceae 3:1 ratio indicates significant anthropogenic violations in the region. We fixed the xerophytic, ruderal, and adventive transformation of grass cover in forest ecosystems. It is also founded the tendency of expanding the fraction of mesophilic plant species due to alterations in water regime (creation of Kremenchug reservoir and draining of floodplain Tyasmyn. When approaching the Cherkasy industrial agglomeration the grass cover degradation is clearly observed on the environmental profile. All this causes the forest ecosystem degradation and gradual loss of forest vegetation typical characteristics. We

Distinguishing natural hydrocarbons from anthropogenic contamination in ground water

International Nuclear Information System (INIS)

Lesage, S.; Xu, H.; Novakowski, K.S.

1997-01-01

Differentiation between natural and anthropogenic sources of ground-water contamination by petroleum hydrocarbons is necessary in areas where natural hydrocarbons may be present in the subsurface. Because of the similarity in composition between natural and refined petroleum, the use of statistical techniques to discern trends is required. In this study, both multivariate plotting techniques and principal component analysis were used to investigate the origin of hydrocarbons from a variety of study sites. Ground-water and gas samples were collected from the Niagara Falls area and from three gasoline stations where leaking underground storage tanks had been found. Although soil gas surveys are used to indicate the presence of hydrocarbons, they were not useful in differentiating between natural and anthropogenic sources of contamination in ground water. Propane and pentene were found to be the most useful chemical parameters in discriminating between the natural and anthropogenic sources. These chemicals are not usually measured in investigations of ground-water contamination, yet analysis can be conducted by most environmental laboratories using conventional methods

Do lake littoral benthic invertebrates respond differently to eutrophication, hydromorphological alteration, land use and fish stocking?

Directory of Open Access Journals (Sweden)

Šiling Rebeka

2016-01-01

Full Text Available In order to provide adequate guidelines in freshwater management, managers need reliable bioindicators that can respond differently to varied stressors. Managers also have to consider hierarchical structure of environmental factors. Thus, our research aims to test the independence of taxa responses along environmental gradients and to examine in what order natural and anthropogenic factors constrain the structure of littoral benthic assemblages. The rank of explained variance of littoral benthic assemblage's variable group hierarchy was: land use > landscape characteristics > eutrophication > fish stocking > hydromorphological alteration. We determined nine gradients (two natural and seven stressor gradients, separated into five groups based on statistically significant differences in responsiveness of taxa. Apart from responsiveness to natural factors, littoral benthic invertebrates could be used as bioindicators for stressors reflecting urbanization, eutrophication, hydromorphological alteration and fish stocking. The taxonomical composition of littoral benthic invertebrates, especially when taxa with preference for certain relatively narrow environmental conditions along gradients are present, can be used to identify effects of key stressors. Our findings have profound implications for ecological assessment and management of lakes, as they indicate that benthic invertebrates can be used when the effects of multiple stressors need to be disentangled.

Impact of anthropogenic and natural environmental changes on Echinococcus transmission in Ningxia Hui Autonomous Region, the People’s Republic of China

Science.gov (United States)

2012-01-01

Echinococcus transmission is known to be affected by various environmental factors, which may be modified by human influence or natural events including global warming. Considerable population growth in the last fifty years in Ningxia Hui Autonomous Region (NHAR), the People’s Republic of China (PRC), has led to dramatic increases in deforestation and modified agricultural practices. In turn, this has resulted in many changes in the habitats for the definitive and intermediate hosts of both Echinococcus granulosus and E. multilocularis, which have increased the risks for transmission of both parasites, affecting echinococcosis prevalence and human disease. Ecological environmental changes due to anthropogenic activities and natural events drive Echinococcus transmission and NHAR provides a notable example illustrating how human activity can impact on a parasitic infection of major public health significance. It is very important to continually monitor these environmental (including climatic) factors that drive the distribution of Echinococcus spp. and their impact on transmission to humans because such information is necessary to formulate reliable future public health policy for echinococcosis control programs and to prevent disease spread. PMID:22827890

Impact of anthropogenic and natural environmental changes on Echinococcus transmission in Ningxia Hui Autonomous Region, the People’s Republic of China

Directory of Open Access Journals (Sweden)

Yang Yu

2012-07-01

Full Text Available Abstract Echinococcus transmission is known to be affected by various environmental factors, which may be modified by human influence or natural events including global warming. Considerable population growth in the last fifty years in Ningxia Hui Autonomous Region (NHAR, the People’s Republic of China (PRC, has led to dramatic increases in deforestation and modified agricultural practices. In turn, this has resulted in many changes in the habitats for the definitive and intermediate hosts of both Echinococcus granulosus and E. multilocularis, which have increased the risks for transmission of both parasites, affecting echinococcosis prevalence and human disease. Ecological environmental changes due to anthropogenic activities and natural events drive Echinococcus transmission and NHAR provides a notable example illustrating how human activity can impact on a parasitic infection of major public health significance. It is very important to continually monitor these environmental (including climatic factors that drive the distribution of Echinococcus spp. and their impact on transmission to humans because such information is necessary to formulate reliable future public health policy for echinococcosis control programs and to prevent disease spread.

Adaptations of lowland jungle mosses to anthropogenic environments in Guyana

OpenAIRE

Kuc, Marian

2000-01-01

Sixteen lowland jungle mosses growing in anthropogenic habitats at Santa and The Bell - Ituni localities on the Demerara River in Guyana were examined in detail with the aim of detecting any features which would indicate their adaptations to new habitats. Amounts of chlorophyll in leaf cells, protective coloration, alterations in leaf morphology, characteristics of old stems, rhizoid tomentum and fertility are considered as the most pronounced adaptive features of these species to new localit...

Focusing on the Interfaces, Estuaries and Redox Transition Zones, for Understanding the Microbial Processes and Biogeochemical Cycling of Carbon under the Looming Influence of Global Warming and Anthropogenic Perturbations

Science.gov (United States)

Dang, H.; Jiao, N.

2013-12-01

Estuaries are the natural interface between terrestrial and marine ecosystems. These are also the zones where human activities exert the strongest impact on the earth and ocean environments. Due to high pressure from the effects of global warming and anthropogenic activities, many estuaries are deteriorating and experiencing significant change of the ecological processes and environmental functions. Certain fundamental microbial processes, including carbon fixation and respiration, have been changing as responses to and consequences of the altered estuarine environment and geochemistry. Increased inputs of terrigenous and anthropogenic organic materials and nutrients and elevated temperature make estuaries easy to be subjected to harmful algal blooms and hypoxic and even anoxic events. The change of the redox status of the estuarine and coastal waters and the increased nutrient loads such as that from terrestrial nitrate stimulate anaerobic respiration processes, such as nitrate reduction and denitrification. This may have strong negative impact on the marine environment, ecosystem and even climate, such as those caused by greenhouse gas production (N2O, CH4) by anaerobic microbial processes. In addition, some nutrients may be consumed by anaerobically respiring heterotrophic microorganisms, instead of being utilized by phytoplankton for carbon fixation. In this regard, the ecological function of the estuarine ecosystem may be altered and the ecological efficiency may be lowered, as less energy is produced by the microbial respiration process and less carbon is fixed by phytoplankton. However, on the other side, in hypoxic and anoxic waters, inorganic carbon fixation by anaerobic microorganisms may happen, such as those via the chemolithoautotrophic denitrifying sulfur oxidizing process and the anaerobic ammonium oxidation (anammox) process. Global warming and anthropogenic perturbations may have lowered the diversity, complexity, stability and sustainability of

Anthropogenic influence of small urban watercourses - Case study from the Czech Republic

Science.gov (United States)

Svobodova, Eva; Jakubinsky, Jiri; Bacova, Radka; Kubicek, Petr; Herber, Vladimir

2013-04-01

Rivers and streams in the urban areas are losing natural environmental values. There is especially small watercourses issue, where there exists the lack of river management and interest of municipalities. The main used methods are based on the field research of river landscape, mapping and inventory of anthropogenic landforms and determination of Channel Capacity Coefficient (CCC). We establish the list of anthropogenic landforms, which we divide to the five categories - industrial, agrarian, urban, transport network, and water management structures. Values of the channel morphologic parameters - width of channel, width of riverbed, and the degree of countersink - are measured for Channel Capacity Coefficient calculation. Pattern of objects shrinking transverse profile and limiting the smooth flow are investigated beside the morphological features. Resulting from the application of these theoretical methods are several practical outputs. Firstly, we construct thematic grid cell monitoring maps (a) count of anthropogenic landforms in the floodplain; (b) weighted average of landform, whose weight was determined on the basis of their influence on the impact of floods. Secondly, we identify pattern distribution of the watercourses channel capacity in the selected study areas. Thirdly, we confirm existence of the urban stream syndrome which is characterized by consistently observed ecological degradation of brooks. The main symptoms of degradation are the altered channel morphology, occurrence of flashfloods, and the rate of ecological stability. Above mentioned characteristics were applied in two different catchments in the Czech Republic - the Leskava Brook and the Lacnovsky Brook. Both streams flow through the urban area in the diverse natural conditions and with various historical development. The Leskava Brook is situated in the southern part of Brno in the Southern Moravia, and the Lacnovsky Brook, lies in the northern part of Svitavy town on the border of Moravia

Assessing Sources of Stress to Aquatic Ecosystems: Using Biomarkers and Bioindicators to Characterize Exodure-Response Profiles of Anthropogenic Activities

Energy Technology Data Exchange (ETDEWEB)

Adams, S.M.

1999-03-29

Establishing causal relationships between sources of environmental stressors and aquatic ecosystem health if difficult because of the many biotic and abiotic factors which can influence or modify responses of biological systems to stress, the orders of magnitude involved in extrapolation over both spatial and temporal scales, and compensatory mechanisms such as density-dependent responses that operate in populations. To address the problem of establishing causality between stressors and effects on aquatic systems, a diagnostic approach, based on exposure-response profiles for various anthropogenic activities, was developed to help identify sources of stress responsible for effects on aquatic systems at ecological significant levels of biological organization (individual, population, community). To generate these exposure-effects profiles, biomarkers of exposure were plotted against bioindicators of corresponding effects for several major anthropogenic activities including petrochemical , pulp and paper, domestic sewage, mining operations, land-development activities, and agricultural activities. Biomarkers of exposure to environmental stressors varied depending on the type of anthropogenic activity involved. Bioindicator effects, however, including histopathological lesions, bioenergetic status, individual growth, reproductive impairment, and community-level responses were similar among many of the major anthropogenic activities. This approach is valuable to help identify and diagnose sources of stressors in environments impacted by multiple stressors. By identifying the types and sources of environmental stressors, aquatic ecosystems can be more effectively protected and managed to maintain acceptable levels of environmental quality and ecosystem fitness.

Anthropogenic Pollutants in Extracts from Maritsa Iztok Dumps

Science.gov (United States)

Stefanova, Maya; Milakovska, Zlatka; Marinov, Stefan

2017-12-01

Coals are suspected for many human health problems and are an object of the new discipline - “medical geology”. Potential human health risk of organic compounds with coal/lignite provenance includes endocrine disruption, nephrotoxicity, cancer, etc. Recent investigations proved that different organic components, i.e. hydrocarbons, phenols etc. move through/release out of the dump area as a result of alteration processes of the organic matter (OM) caused by the wash-out and/or drainage processes. The timeliness of the present study is based on the scarcity of information on organic geochemistry of dump materials from open pit coal mines and weathered lignites in particular. The limited number of studies on dumps clarifies that even for the “short” time span (some tens of years) in geological point of view, processes of transformation of the extractable OM are detectable. The secondary phases, a result of the OM transformations, move through and out of the dump area and could be potential contaminants for the surface/underground waters and soils in the area. Another environmental problem comes from the air-born VOCs and products of the modern chemical industry. By GC-MS in the slightly polar fractions of the chloroform extracts of dump samples a broad set of components was determined, i.e. phthalates (dominant), i-propyl palmitate, i-propyl myristate, n-hexyl benzoates, etc. These organic contaminants could be regarded more likely as anthropogenic (originating from plasticizers, industrial pollutants, etc.). Presently, it seems that the identified compounds do not represent an acute toxic risk from an environmental viewpoint. However, some compounds could raise concerns and further attention is needed to be focused on them.

Response of the photosynthetic system to altered protein composition and changes in environmental conditions

NARCIS (Netherlands)

Tóth, T.

2014-01-01

The photosynthetic thylakoid membrane has a hierarchically ordered structure containing pigment-protein complexes that capture solar radiation and convert it into chemical energy. Its highly dynamic structure is capable to continuously respond to the altered environmental conditions, e.g., light

Anthropogenic fragmentation may not alter pre-existing patterns of genetic diversity and differentiation in perennial shrubs.

Science.gov (United States)

Llorens, Tanya M; Ayre, David J; Whelan, Robert J

2018-04-01

Many plant species have pollination and seed dispersal systems and evolutionary histories that have produced strong genetic structuring. These genetic patterns may be consistent with expectations following recent anthropogenic fragmentation, making it difficult to detect fragmentation effects if no prefragmentation genetic data are available. We used microsatellite markers to investigate whether severe habitat fragmentation may have affected the structure and diversity of populations of the endangered Australian bird-pollinated shrub Grevillea caleyi R.Br., by comparing current patterns of genetic structure and diversity with those of the closely related G. longifolia R.Br. that has a similar life history but has not experienced anthropogenic fragmentation. Grevillea caleyi and G. longifolia showed similar and substantial population subdivision at all spatial levels (global F' ST  = 0.615 and 0.454; S p  = 0.039 and 0.066), marked isolation by distance and large heterozygous deficiencies. These characteristics suggest long-term effects of inbreeding in self-compatible species that have poor seed dispersal, limited connectivity via pollen flow and undergo population bottlenecks because of periodic fires. Highly structured allele size distributions, most notably in G. caleyi, imply historical processes of drift and mutation were important in isolated subpopulations. Genetic diversity did not vary with population size but was lower in more isolated populations for both species. Through this comparison, we reject the hypothesis that anthropogenic fragmentation has impacted substantially on the genetic composition or structure of G. caleyi populations. Our results suggest that highly self-compatible species with limited dispersal may be relatively resilient to the genetic changes predicted to follow habitat fragmentation. © 2018 John Wiley & Sons Ltd.

Laboratory experiments on dynamics of anthropogenic ferrimagnetics in sand formations

Czech Academy of Sciences Publication Activity Database

Kapička, Aleš; Fialová, Hana; Petrovský, Eduard; Kodešová, R.; Kopáč, J.

2008-01-01

Roč. 38, Special issue (2008), s. 52-53 ISSN 1335-2806. [Paleo, Rock and Environmental Magnetism. Castle Meeting /11./. 22.06.2008-28.06.2008, Bojnice] R&D Projects: GA AV ČR IAA300120701 Institutional research plan: CEZ:AV0Z30120515 Keywords : soil pollution * dynamics of anthropogenic particles * magnetic susceptibility Subject RIV: DE - Earth Magnetism, Geodesy, Geography

Island biogeography and landscape structure: Integrating ecological concepts in a landscape perspective of anthropogenic impacts in temporary wetlands

International Nuclear Information System (INIS)

Angeler, David G.; Alvarez-Cobelas, Miguel

2005-01-01

Although our understanding of environmental risk assessment in temporary wetlands has been improved by the use of multi-species toxicity testing, we still know little of how landscape variables mediate the strength of, and recovery from, anthropogenic stress in such ecosystems. To bridge this research gap, we provide a theoretical framework of the response of temporary wetlands to anthropogenic disturbance along a habitat-isolation continuum based on island biogeography theory, landscape ecology and dispersal and colonization strategies of temporary wetland organisms. - Environmental risk assessment in temporary wetlands may benefit from consideration of island biogeography theory and landscape structure

The importance of invertebrates when considering the impacts of anthropogenic noise.

Science.gov (United States)

Morley, Erica L; Jones, Gareth; Radford, Andrew N

2014-02-07

Anthropogenic noise is now recognized as a major global pollutant. Rapidly burgeoning research has identified impacts on individual behaviour and physiology through to community disruption. To date, however, there has been an almost exclusive focus on vertebrates. Not only does their central role in food webs and in fulfilling ecosystem services make imperative our understanding of how invertebrates are impacted by all aspects of environmental change, but also many of their inherent characteristics provide opportunities to overcome common issues with the current anthropogenic noise literature. Here, we begin by explaining why invertebrates are likely to be affected by anthropogenic noise, briefly reviewing their capacity for hearing and providing evidence that they are capable of evolutionary adaptation and behavioural plasticity in response to natural noise sources. We then discuss the importance of quantifying accurately and fully both auditory ability and noise content, emphasizing considerations of direct relevance to how invertebrates detect sounds. We showcase how studying invertebrates can help with the behavioural bias in the literature, the difficulties in drawing strong, ecologically valid conclusions and the need for studies on fitness impacts. Finally, we suggest avenues of future research using invertebrates that would advance our understanding of the impact of anthropogenic noise.

Complex demographic heterogeneity from anthropogenic impacts in a coastal marine predator.

Science.gov (United States)

Oro, Daniel; Álvarez, David; Velando, Alberto

2018-04-01

Environmental drivers, including anthropogenic impacts, affect vital rates of organisms. Nevertheless, the influence of these drivers may depend on the physical features of the habitat and how they affect life history strategies depending on individual covariates such as age and sex. Here, the long-term monitoring (1994-2014) of marked European Shags in eight colonies in two regions with different ecological features, such as foraging habitat, allowed us to test several biological hypotheses about how survival changes by age and sex in each region by means of multi-event capture-recapture modeling. Impacts included fishing practices and bycatch, invasive introduced carnivores and the severe Prestige oil spill. Adult survival was constant but, unexpectedly, it was different between sexes. This difference was opposite in each region. The impact of the oil spill on survival was important only for adults (especially for females) in one region and lasted a single year. Juvenile survival was time dependent but this variability was not synchronized between regions, suggesting a strong signal of regional environmental variability. Mortality due to bycatch was also different between sex, age and region. Interestingly the results showed that the size of the fishing fleet is not necessarily a good proxy for assessing the impact of bycatch mortality, which may be more dependent on the fishing grounds and the fishing gears employed in each season of the year. Anthropogenic impacts affected survival differently by age and sex, which was expected for a long-lived organism with sexual size dimorphism. Strikingly, these differences varied depending on the region, indicating that habitat heterogeneity is demographically important to how environmental variability (including anthropogenic impacts) and resilience influence population dynamics. © 2018 by the Ecological Society of America.

Conservation implications of anthropogenic impacts on visual communication and camouflage.

Science.gov (United States)

Delhey, Kaspar; Peters, Anne

2017-02-01

Anthropogenic environmental impacts can disrupt the sensory environment of animals and affect important processes from mate choice to predator avoidance. Currently, these effects are best understood for auditory and chemosensory modalities, and recent reviews highlight their importance for conservation. We examined how anthropogenic changes to the visual environment (ambient light, transmission, and backgrounds) affect visual communication and camouflage and considered the implications of these effects for conservation. Human changes to the visual environment can increase predation risk by affecting camouflage effectiveness, lead to maladaptive patterns of mate choice, and disrupt mutualistic interactions between pollinators and plants. Implications for conservation are particularly evident for disrupted camouflage due to its tight links with survival. The conservation importance of impaired visual communication is less documented. The effects of anthropogenic changes on visual communication and camouflage may be severe when they affect critical processes such as pollination or species recognition. However, when impaired mate choice does not lead to hybridization, the conservation consequences are less clear. We suggest that the demographic effects of human impacts on visual communication and camouflage will be particularly strong when human-induced modifications to the visual environment are evolutionarily novel (i.e., very different from natural variation); affected species and populations have low levels of intraspecific (genotypic and phenotypic) variation and behavioral, sensory, or physiological plasticity; and the processes affected are directly related to survival (camouflage), species recognition, or number of offspring produced, rather than offspring quality or attractiveness. Our findings suggest that anthropogenic effects on the visual environment may be of similar importance relative to conservation as anthropogenic effects on other sensory modalities

Evaluation of anthropogenic urban soils. Final report; Bewertung anthropogener Stadtboeden. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Blume, H.P.; Schleuss, U. [eds.

1997-12-31

The research project `Evaluation of Anthropogenic Urban Soils` was subsidized by the German Federal Ministry of Education, Science, Research and Technology and adviced by the working group `Stadtboeden` of the German Society of Soil Science. It was realized as a cooperation between the universities of Berlin (TU), Halle-Wittenberg, Hohenheim, Kiel and Rostock and had three objectives: - to characterize soils developed from anthropogenic substratums (`urban soils`), - to figure out distribution patterns of such soils and - to verify whether urban soils could be evaluated according to their filtering and habitat function in the same way as soils developed from natural parent material. Evaluation methods based on easily obtainable field data had to be adapted to `urban soils` respectively developed anew. For that reason some typical soils of anthropogenic lithogenesis had to be examined between 1993 and 1996 both on their importance as habitats for plants and soil organisms and on their filtering, buffering and transforming capacities for organic and inorganic pollutants. Accordingly representative `urban soils` were gathered in the towns of Berlin, Eckernfoerde, Essen, Halle, Kiel, Rostock and Stuttgart; these soils had developed from technogenic substratums (brick and mortar debris, municipal waste, ashes, slag, sludge) and redeposited alkaline resp. acidic natural substratums (mud, coal mine and coking plant deposits). Some of the soils were influenced by ground water, and all soils developed from the same kind of parent material belonged to different stages of development. (orig./SR) [Deutsch] Ziele des vom BMBF gefoerderten und vom Arbeitskreis Stadtboeden der Deutschen Bodenkundlichen Gesellschaft beratenen Verbundprojektes `Bewertung anthropogener Stadtboeden` waren die Charakterisierung von Boeden anthropogener Substrate, die exemplarische Ermittlung des Verteilungsmusters derartiger Boeden und die Pruefung, inwieweit sie sich aehnlich den Boeden natuerlicher

Anthropogenic impacts on mosquito populations in North America over the past century

Science.gov (United States)

Rochlin, Ilia; Faraji, Ary; Ninivaggi, Dominick V.; Barker, Christopher M.; Kilpatrick, A. Marm

2016-12-01

The recent emergence and spread of vector-borne viruses including Zika, chikungunya and dengue has raised concerns that climate change may cause mosquito vectors of these diseases to expand into more temperate regions. However, the long-term impact of other anthropogenic factors on mosquito abundance and distributions is less studied. Here, we show that anthropogenic chemical use (DDT; dichlorodiphenyltrichloroethane) and increasing urbanization were the strongest drivers of changes in mosquito populations over the last eight decades in areas on both coasts of North America. Mosquito populations have increased as much as tenfold, and mosquito communities have become two- to fourfold richer over the last five decades. These increases are correlated with the decay in residual environmental DDT concentrations and growing human populations, but not with temperature. These results illustrate the far-reaching impacts of multiple anthropogenic disturbances on animal communities and suggest that interactions between land use and chemical use may have unforeseen consequences on ecosystems.

Slope Reinforcement with the Utilization of the Coal Waste Anthropogenic Material

Science.gov (United States)

Gwóźdź-Lasoń, Monika

2017-10-01

The protection of the environment, including waste management, is one of the pillars of the policy of the Europe. The application which is presented in that paper tries to show a trans-disciplinary way to design geotechnical constructions - slope stability analysis. The generally accepted principles that the author presents are numerous modelling patterns of earth retaining walls as slope stabilization system. The paper constitutes an attempt to summarise and generalise earlier researches which involved FEM numeric procedures and the Z_Soil package. The design of anthropogenic soil used as a material for reinforced earth retaining walls, are not only of commercial but of environmental importance as well and consistent with the concept of sustainable development and the need to redevelop brownfield. This paper tries to show conceptual and empirical modelling approaches to slope stability system used in anthropogenic soil formation such as heaps, resulting from mining, with a special focus on urban areas of South of Poland and perspectives of anthropogenic materials application in geotechnical engineering are discussed.

Baseline for Climate Change: Modeling Watershed Aquatic Biodiversity Relative to Environmental and Anthropogenic Factors

Energy Technology Data Exchange (ETDEWEB)

Maurakis, Eugene G

2010-10-01

Objectives of the two-year study were to (1) establish baselines for fish and macroinvertebrate community structures in two mid-Atlantic lower Piedmont watersheds (Quantico Creek, a pristine forest watershed; and Cameron Run, an urban watershed, Virginia) that can be used to monitor changes relative to the impacts related to climate change in the future; (2) create mathematical expressions to model fish species richness and diversity, and macroinvertebrate taxa and macroinvertebrate functional feeding group taxa richness and diversity that can serve as a baseline for future comparisons in these and other watersheds in the mid-Atlantic region; and (3) heighten people’s awareness, knowledge and understanding of climate change and impacts on watersheds in a laboratory experience and interactive exhibits, through internship opportunities for undergraduate and graduate students, a week-long teacher workshop, and a website about climate change and watersheds. Mathematical expressions modeled fish and macroinvertebrate richness and diversity accurately well during most of the six thermal seasons where sample sizes were robust. Additionally, hydrologic models provide the basis for estimating flows under varying meteorological conditions and landscape changes. Continuations of long-term studies are requisite for accurately teasing local human influences (e.g. urbanization and watershed alteration) from global anthropogenic impacts (e.g. climate change) on watersheds. Effective and skillful translations (e.g. annual potential exposure of 750,000 people to our inquiry-based laboratory activities and interactive exhibits in Virginia) of results of scientific investigations are valuable ways of communicating information to the general public to enhance their understanding of climate change and its effects in watersheds.

Separating natural acidity from anthropogenic acidification in the spring flood of northern Sweden

International Nuclear Information System (INIS)

Laudon, Hjalmar

2000-01-01

Spring flood is an occasion for transient hydrochemical changes that profoundly effect the biodiversity of the aquatic ecosystem. Spring flood is also very susceptible to anthropogenic acidification. Belief that acid deposition is primarily responsible for pH decline during spring flood has been an important factor in the decision to spend close to one billion Swedish crowns to lime surface waters in northern Sweden during the last decade. The objective of this work is to present an operational tool, the Boreal Dilution Model (BDM), for separating and quantifying the anthropogenic and natural contributions to episodic acidification during spring flood episodes in northern Sweden. The limited data requirements of 10-15 stream water samples before and during spring flood make the BDM suitable for widespread use in environmental monitoring programs. This creates a possibility for distinguishing trends and spatial patterns in the human impact as well as natural pH decline. The results from applying the BDM, and a one point 'pBDM' version of the model, in northern Sweden demonstrate that the anthropogenic component associated with spring flood episodes is now generally limited. Instead it is the combination of natural organic acidity and dilution of the buffering capacity that is the major driving mechanism of episodic acidity during spring flood events in the region. While the anthropogenic component of episodic acidification generally contributes 0.1 to 0.3 pH units to the natural pH decline of up to 2.5 pH units, the current regional extent of areas that are severely affected by anthropogenically driven episodes is approximately 6%. Prior to the initiation of the Swedish Environmental Protection Agency's 'Episode Project' the limited spring flood data together with lack of a systematic methodology for determining liming candidates forced the liming authorities to base the remediation strategy in northern Sweden on biological indications. But, since there are more

Environmental and Anthropogenic Impacts on Avifaunal Assemblages in an Urban Parkland, 1976 to 2007

Directory of Open Access Journals (Sweden)

Sara Elizabeth Ormond

2014-03-01

Full Text Available Urban environments are unique, rapidly changing habitats in which almost half of the world’s human population resides. The effects of urbanisation, such as habitat (vegetation removal, pollution and modification of natural areas, commonly cause biodiversity loss. Long-term ecological monitoring of urban environments is vital to determine the composition and long-term trends of faunal communities. This paper provides a detailed view of long-term changes in avifaunal assemblages of the Adelaide City parklands and discusses the anthropogenic and environmental factors that contributed to the changes between 1976 and 2007. The Adelaide City parklands (ACP comprise 760 ha of land surrounding Adelaide’s central business district. Naturalist Robert Whatmough completed a 32-year survey of the ACP to determine the structure of the urban bird community residing there. Annual species richness and the abundance of birds in March and September months were analysed. Linear regression analysis was applied to species richness and abundance data of each assemblage. Resident parkland birds demonstrated significant declines in abundance. Native and introduced species also exhibited long-term declines in species richness and abundance throughout the 32-year period. Cycles of varying time periods indicated fluctuations in avian biodiversity demonstrating the need for future monitoring and statistical analyses on bird communities in the Adelaide City parklands.

Ecophysiology and anthropogenic environmental changes

Energy Technology Data Exchange (ETDEWEB)

Haertel, O

1971-01-01

The problems caused by man in relation to environmental pollution are reviewed. Attention is focused on increased air pollution, the major sources of which are industries, automobiles and home heating. Increased use of herbicides, insecticides, and fertilizers pollute the air as well as rivers and the soil. The processes involved in sulfur dioxide attacking plant cells and the sensitivity of lichens to sulfur dioxide are discussed. Along with sulfur dioxide, fluorine compounds, peroxyacetyl nitrate, hydrogen sulfides, nitrogen oxides and carbon monoxide are appearing more and more as injurious agents in the air. In addition, every time fossil fuel is burned, carbon dioxide is returned to the atmosphere. Some 10 tons of carbon dioxide are thrown into the air annually through combustion, thereby leading to higher mean temperatures in the troposphere.

Environmental and ecological changes associated with a marina.

Science.gov (United States)

Rivero, Natalie K; Dafforn, Katherine A; Coleman, Melinda A; Johnston, Emma L

2013-01-01

Anthropogenic modifications to waterways are common and their ecological consequences must be understood to effectively conserve local biodiversity. The facilitation of recreational boating activities often requires substantial alteration of natural areas, however the environmental and ecological consequences of such alterations are rarely described in the scientific literature. In this study, ecological and physico-chemical conditions were investigated in a recreational boating marina, located inside a marine park on the south-east coast of Australia. Recruitment panels were deployed for 8 weeks both inside and outside the marina, and differences in the composition of the developing fouling communities were observed. The recruitment of taxa, which often have short-lived larvae, was increased inside the marina (bryozoans, spirorbids and sponges) while the recruitment of taxa, which often have longer-lived larvae, was reduced or absent (barnacles, solitary ascidians and non-spirorbid polychaetes). Differences were also observed in environmental conditions inside the marina cf. directly outside. The marina environment had higher turbidity, temperature and pH along with higher concentrations of lead and copper in suspended sediments, while flow rates and trapped sediment loads were reduced inside the marina. The differences observed in the study suggest that there may be marked environmental changes associated with marina developments. The potential ecological consequences of these changes should be a primary consideration during the planning process, particularly for developments in locations of notable ecological value.

Sinks as integrative elements of the anthropogenic metabolism

Science.gov (United States)

Kral, Ulrich; Brunner, Paul H.

2015-04-01

The anthropogenic metabolism is an open system requiring exchange of materials and energy between the anthroposphere and the environment. Material and energy flows are taken from nature and become utilized by men. After utilization, the materials either remain in the anthroposphere as recycling products, or they leave the anthroposphere as waste and emission flows. To accommodate these materials without jeopardizing human and environmental health, limited natural sinks are available; thus, man-made sinks have to be provided where natural sinks are missing or overloaded. The oral presentation (1) suggests a coherent definition of the term "sink", encompassing natural and man-made processes, (2) presents a framework to analyse and evaluate anthropogenic material flows to sinks, based on the tool substance flow analysis and impact assessment methodology, and (3) applies the framework in a case study approach for selected substances such as Copper and Lead in Vienna and Perfluorooctane sulfonate in Switzerland. Finally, the numeric results are aggregated in terms of a new indicator that specifies on a regional scale which fractions of anthropogenic material flows to sinks are acceptable. The following results are obtained: In Vienna, 99% of Cu flows to natural and man-made sinks are in accordance with accepted standards. However, the 0.7% of Cu entering urban soils and the 0.3% entering receiving waters surpass the acceptable level. In the case of Pb, 92% of all flows into sinks prove to be acceptable, but 8% are disposed of in local landfills with limited capacity. For PFOS, 96% of all flows into sinks are acceptable. 4% cannot be evaluated due to a lack of normative criteria, despite posing a risk for human health and the environment. The case studies corroborate the need and constraints of sinks to accommodate inevitable anthropogenic material flows.

Physical habitat and its alteration: A common ground for exposure of amphibians to environmental stressors

Science.gov (United States)

Bishop, Christine A.; Cunnington, David C.; Fellers, Gary M.; Gibbs, James P.; Pauli, Bruce D.; Rothermel, Betsie B.; Linder, Greg L.; Krest, Sherry K.; Sparling, Donald W.

2003-01-01

Amphibians as a class of vertebrates have persisted for hundreds of millions of years (Stebbins and Cohen 1995), but they are currently threatened by a variety of stressors, many resulting from human-related alterations of the environment. Most species of amphibians live closely associated with moist environments throughout their life and have evolved specialized adaptations that conserve water and reduce desiccation (Stebbins and Cohen 1995; Henry 2000; Chapter 2A). Amphibians are ectotherms, so their body temperatures fluctuate with the local environment. Latitude, elevation, and habitat affect environmental temperature and have a strong influence on amphibian distributions. Despite these physiological and habitat constraints, the 4750 species of amphibians in the world today have exploited a wide variety of habitats that range from dry deserts to tropical rain forests and from sea level to elevations above 4000 m (McDairmid and Mitchell 2000).The direct loss of suitable habitat has had a profound effect on amphibian populations (Johnson 1992), as it has on nearly all species of wildlife. In the U.S., 53% of wetlands have been lost to human development in the last 200 years (Dahl 1990). Similar loss of wetlands has occurred throughout much of the world, especially in developing countries (Miller 1993). In many regions, deforestation has reduced or eliminated suitable terrestrial habitats, and this may prove to be the largest global threat to amphibian populations (Johnson 1992). Eight thousand years ago, forests covered approximately 40% of the world’s land (6 billion hectares), but by 1997, the world’s forests had been reduced to 3.5 billion hectares, a 42% loss worldwide (CIDA 2001). The effect of habitat loss is generally both obvious and predictable; with increasing restriction of suitable habitat, amphibian populations will probably not survive. The anthropogenic effects on the quality of the habitat that remains are often less obvious.

Timing anthropogenic stressors to mitigate their impact on marine ecosystem resilience

OpenAIRE

Wu, Paul Pao-Yen; Mengersen, Kerrie; McMahon, Kathryn; Kendrick, Gary A.; Chartrand, Kathryn; York, Paul H.; Rasheed, Michael A.; Caley, M. Julian

2017-01-01

Better mitigation of anthropogenic stressors on marine ecosystems is urgently needed to address increasing biodiversity losses worldwide. We explore opportunities for stressor mitigation using whole-of-systems modelling of ecological resilience, accounting for complex interactions between stressors, their timing and duration, background environmental conditions and biological processes. We then search for ecological windows, times when stressors minimally impact ecological resilience, defined...

Detecting Anthropogenic Disturbance on Weathering and Erosion Processes

Science.gov (United States)

Vanacker, V.; Schoonejans, J.; Bellin, N.; Ameijeiras-Mariño, Y.; Opfergelt, S.; Christl, M.

2014-12-01

Anthropogenic disturbance of natural vegetation can profoundly alter the physical, chemical and biological processes within soils. Rapid removal of topsoil during intense farming can result in an imbalance between soil production through chemical weathering and physical erosion, with direct implications on local biogeochemical cycling. However, the feedback mechanisms between soil erosion, chemical weathering and biogeochemical cycling in response to anthropogenic forcing are not yet fully understood. In this paper, we analyze dynamic soil properties for a rapidly changing anthropogenic landscape in the Spanish Betic Cordillera; and focus on the coupling between physical erosion, soil production and soil chemical weathering. Modern erosion rates were quantified through analysis of sediment deposition volumes behind check dams, and represent catchment-average erosion rates over the last 10 to 50 years. Soil production rates are derived from in-situ produced 10Be nuclide concentrations, and represent long-term flux rates. In each catchment, soil chemical weathering intensities were calculated for two soil-regolith profiles. Although Southeast Spain is commonly reported as the European region that is most affected by land degradation, modern erosion rates are low (140 t ha-1 yr-1). About 50 % of the catchments are losing soils at a rate of less than 60 t km-2 yr-1. Our data show that modern erosion rates are roughly of the same magnitude as the long-term or cosmogenically-derived erosion rates in the Betic Cordillera. Soils developed on weathered metamorphic rocks have no well-developed profile characteristics, and are generally thin and stony. Nevertheless, soil chemical weathering intensities are high; and question the occurrence of past soil truncation.

Possible influence of anthropogenic aerosols on cirrus clouds and anthropogenic forcing

Directory of Open Access Journals (Sweden)

J. E. Penner

2009-02-01

Full Text Available Cirrus clouds have a net warming effect on the atmosphere and cover about 30% of the Earth's area. Aerosol particles initiate ice formation in the upper troposphere through modes of action that include homogeneous freezing of solution droplets, heterogeneous nucleation on solid particles immersed in a solution, and deposition nucleation of vapor onto solid particles. Here, we examine the possible change in ice number concentration from anthropogenic soot originating from surface sources of fossil fuel and biomass burning, from anthropogenic sulfate aerosols, and from aircraft that deposit their aerosols directly in the upper troposphere. We use a version of the aerosol model that predicts sulfate number and mass concentrations in 3-modes and includes the formation of sulfate aerosol through homogeneous binary nucleation as well as a version that only predicts sulfate mass. The 3-mode version best represents the Aitken aerosol nuclei number concentrations in the upper troposphere which dominated ice crystal residues in the upper troposphere. Fossil fuel and biomass burning soot aerosols with this version exert a radiative forcing of −0.3 to −0.4 Wm⁻² while anthropogenic sulfate aerosols and aircraft aerosols exert a forcing of −0.01 to 0.04 Wm⁻² and −0.16 to −0.12 Wm⁻², respectively, where the range represents the forcing from two parameterizations for ice nucleation. The sign of the forcing in the mass-only version of the model depends on which ice nucleation parameterization is used and can be either positive or negative. The magnitude of the forcing in cirrus clouds can be comparable to the forcing exerted by anthropogenic aerosols on warm clouds, but this forcing has not been included in past assessments of the total anthropogenic radiative forcing of climate.

Aqueous Neem Extract Versus Neem Powder on Culex quinquefasciatus: Implications for Control in Anthropogenic Habitats

OpenAIRE

Kudom, Andreas A.; Mensah, Ben A.; Botchey, Mary A.

2011-01-01

Control programs using conventional insecticides to target anthropogenic mosquito habitats are very expensive because these habitats are widespread, particularly in cities of most African countries. Additionally, there are serious environmental concerns regarding large-scale application of most conventional insecticides. Clearly there is a need for alternative methods that are more effective, less expensive, and environmentally friendly. One such method would be the application of preparation...

Anthropogenic disturbances jeopardize biodiversity conservation within tropical rainforest reserves.

Science.gov (United States)

Martínez-Ramos, Miguel; Ortiz-Rodríguez, Iván A; Piñero, Daniel; Dirzo, Rodolfo; Sarukhán, José

2016-05-10

Anthropogenic disturbances affecting tropical forest reserves have been documented, but their ecological long-term cumulative effects are poorly understood. Habitat fragmentation and defaunation are two major anthropogenic threats to the integrity of tropical reserves. Based on a long-term (four decades) study, we document how these disturbances synergistically disrupt ecological processes and imperil biodiversity conservation and ecosystem functioning at Los Tuxtlas, the northernmost tropical rainforest reserve in the Americas. Deforestation around this reserve has reduced the reserve to a medium-sized fragment (640 ha), leading to an increased frequency of canopy-gap formation. In addition, hunting and habitat loss have caused the decline or local extinction of medium and large herbivores. Combining empirical, experimental, and modeling approaches, we support the hypothesis that such disturbances produced a demographic explosion of the long-lived (≈120 y old, maximum height of 7 m) understory palm Astrocaryum mexicanum, whose population has increased from 1,243-4,058 adult individuals per hectare in only 39 y (annual growth rate of ca 3%). Faster gap formation increased understory light availability, enhancing seed production and the growth of immature palms, whereas release from mammalian herbivory and trampling increased survival of seedlings and juveniles. In turn, the palm's demographic explosion was followed by a reduction of tree species diversity, changing forest composition, altering the relative contribution of trees to forest biomass, and disrupting litterfall dynamics. We highlight how indirect anthropogenic disturbances (e.g., palm proliferation) on otherwise protected areas threaten tropical conservation, a phenomenon that is currently eroding the planet's richest repositories of biodiversity.

Het verband tussen natuurlijke en anthropogene landschapsvormen, bezien vanuit de betrekkingen in grensmilieu’s

NARCIS (Netherlands)

Leeuwen, van Chr.G.

1965-01-01

The isomorphy of natural and anthropogeneous landscapes with regard to the environmental conditions in border areas The contact in space between opposite situations constitutes two main types of boundaries. The distinction of these two types offers a useful expedient in ecology. It may also clarify

Tracing diffuse anthropogenic Pb sources in rural soils by means of Pb isotope analysis

NARCIS (Netherlands)

Walraven, N.; Gaans, P.F.M. van; Veer, G. van der; Os, B.J.H. van; Klaver, G.T.; Vriend, S.P.; Middelburg, J.J.; Davies, G.R.

2013-01-01

Knowledge of the cause and source of Pb pollution is important to abate environmental Pb pollution by taking source-related actions. Lead isotope analysis is a potentially powerful tool to identify anthropogenic Pb and its sources in the environment. Spatial information on the variation of

Future potential distribution of the emerging amphibian chytrid fungus under anthropogenic climate change.

Science.gov (United States)

Rödder, Dennis; Kielgast, Jos; Lötters, Stefan

2010-11-01

Anthropogenic climate change poses a major threat to global biodiversity with a potential to alter biological interactions at all spatial scales. Amphibians are the most threatened vertebrates and have been subject to increasing conservation attention over the past decade. A particular concern is the pandemic emergence of the parasitic chytrid fungus Batrachochytrium dendrobatidis, which has been identified as the cause of extremely rapid large-scale declines and species extinctions. Experimental and observational studies have demonstrated that the host-pathogen system is strongly influenced by climatic parameters and thereby potentially affected by climate change. Herein we project a species distribution model of the pathogen onto future climatic scenarios generated by the IPCC to examine their potential implications on the pandemic. Results suggest that predicted anthropogenic climate change may reduce the geographic range of B. dendrobatidis and its potential influence on amphibian biodiversity.

Long-term nitrogen amendment alters the diversity and assemblage of soil bacterial communities in tallgrass prairie.

Directory of Open Access Journals (Sweden)

Joseph D Coolon

Full Text Available Anthropogenic changes are altering the environmental conditions and the biota of ecosystems worldwide. In many temperate grasslands, such as North American tallgrass prairie, these changes include alteration in historically important disturbance regimes (e.g., frequency of fires and enhanced availability of potentially limiting nutrients, particularly nitrogen. Such anthropogenically-driven changes in the environment are known to elicit substantial changes in plant and consumer communities aboveground, but much less is known about their effects on soil microbial communities. Due to the high diversity of soil microbes and methodological challenges associated with assessing microbial community composition, relatively few studies have addressed specific taxonomic changes underlying microbial community-level responses to different fire regimes or nutrient amendments in tallgrass prairie. We used deep sequencing of the V3 region of the 16S rRNA gene to explore the effects of contrasting fire regimes and nutrient enrichment on soil bacterial communities in a long-term (20 yrs experiment in native tallgrass prairie in the eastern Central Plains. We focused on responses to nutrient amendments coupled with two extreme fire regimes (annual prescribed spring burning and complete fire exclusion. The dominant bacterial phyla identified were Proteobacteria, Verrucomicrobia, Bacteriodetes, Acidobacteria, Firmicutes, and Actinobacteria and made up 80% of all taxa quantified. Chronic nitrogen enrichment significantly impacted bacterial community diversity and community structure varied according to nitrogen treatment, but not phosphorus enrichment or fire regime. We also found significant responses of individual bacterial groups including Nitrospira and Gammaproteobacteria to long-term nitrogen enrichment. Our results show that soil nitrogen enrichment can significantly alter bacterial community diversity, structure, and individual taxa abundance, which have

Airborne anthropogenic radioactivity measurements from an international radionuclide monitoring system

International Nuclear Information System (INIS)

Mason, L.R.; Bohner, J.D.; Williams, D.L.

1998-01-01

Anthropogenic radioactivity is being measured in near-real time by an international monitoring system designed to verify the Comprehensive Nuclear Test Ban Treaty. Airborne radioactivity measurements are conducted in-situ by stations that are linked to a central data processing and analysis facility. Aerosols are separated by high-volume air sampling with high-efficiency particulate filters. Radio-xenon is separated from other gases through cryogenic methods. Gamma-spectrometry is performed by high purity germanium detectors and the raw spectral data is immediately transmitted to the central facility via Internet, satellite, or modem. These highly sensitive sensors, combined with the automated data processing at the central facility, result in a system capable of measuring environmental radioactivity on the microbecquerel scale where the data is available to scientists within minutes of the field measurement. During the past year, anthropogenic radioactivity has been measured at approximately half of the stations in the current network. Sources of these measured radionuclides include nuclear power plant emissions, Chernobyl resuspension, and isotope production facilities. The ability to thoroughly characterize site-specific radionuclides, which contribute to the radioactivity of the ambient environment, will be necessary to reduce the number of false positive events. This is especially true of anthropogenic radionuclides that could lead to ambiguous analysis. (author)

Symbiotic bacteria of helminths: what role may they play in ecosystems under anthropogenic stress?

Science.gov (United States)

Morley, N J

2016-11-01

Symbiotic bacteria are a common feature of many animals, particularly invertebrates, from both aquatic and terrestrial habitats. These bacteria have increasingly been recognized as performing an important role in maintaining invertebrate health. Both ecto- and endoparasitic helminths have also been found to harbour a range of bacterial species which provide a similar function. The part symbiotic bacteria play in sustaining homeostasis of free-living invertebrates exposed to anthropogenic pressure (climate change, pollution), and the consequences to invertebrate populations when their symbionts succumb to poor environmental conditions, are increasingly important areas of research. Helminths are also susceptible to environmental stress and their symbiotic bacteria may be a key aspect of their responses to deteriorating conditions. This article summarizes the ecophysiological relationship helminths have with symbiotic bacteria and the role they play in maintaining a healthy parasite and the relevance of specific changes that occur in free-living invertebrate-bacteria interactions under anthropogenic pressure to helminths and their bacterial communities. It also discusses the importance of understanding the mechanistic sensitivity of helminth-bacteria relationships to environmental stress for comprehending the responses of parasites to challenging conditions.

Environmentally induced epigenetic transgenerational inheritance of altered Sertoli cell transcriptome and epigenome: molecular etiology of male infertility.

Directory of Open Access Journals (Sweden)

Carlos Guerrero-Bosagna

Full Text Available Environmental toxicants have been shown to induce the epigenetic transgenerational inheritance of adult onset disease, including testis disease and male infertility. The current study was designed to determine the impact of an altered sperm epigenome on the subsequent development of an adult somatic cell (Sertoli cell that influences the onset of a specific disease (male infertility. A gestating female rat (F0 generation was exposed to the agriculture fungicide vinclozolin during gonadal sex determination and then the subsequent F3 generation progeny used for the isolation of Sertoli cells and assessment of testis disease. As previously observed, enhanced spermatogenic cell apoptosis was observed. The Sertoli cells provide the physical and nutritional support for the spermatogenic cells. Over 400 genes were differentially expressed in the F3 generation control versus vinclozolin lineage Sertoli cells. A number of specific cellular pathways were identified to be transgenerationally altered. One of the key metabolic processes affected was pyruvate/lactate production that is directly linked to spermatogenic cell viability. The Sertoli cell epigenome was also altered with over 100 promoter differential DNA methylation regions (DMR modified. The genomic features and overlap with the sperm DMR were investigated. Observations demonstrate that the transgenerational sperm epigenetic alterations subsequently alters the development of a specific somatic cell (Sertoli cell epigenome and transcriptome that correlates with adult onset disease (male infertility. The environmentally induced epigenetic transgenerational inheritance of testis disease appears to be a component of the molecular etiology of male infertility.

Attenuating initial beliefs: Increasing the acceptance of anthropogenic climate change information by reflecting on values

NARCIS (Netherlands)

van Prooijen, A.M.; Sparks, P.

2014-01-01

Anthropogenic climate change information tends to be interpreted against the backdrop of initial environmental beliefs, which can lead to some people being resistant toward the information. In this article (N = 88), we examined whether self-affirmation via reflection on personally important values

Atmospheric mercury emissions in Australia from anthropogenic, natural and recycled sources

Science.gov (United States)

Nelson, Peter F.; Morrison, Anthony L.; Malfroy, Hugh J.; Cope, Martin; Lee, Sunhee; Hibberd, Mark L.; Meyer, C. P. (Mick); McGregor, John

2012-12-01

The United Nations Environment Programme (UNEP) has begun a process of developing a legally binding instrument to manage emissions of mercury from anthropogenic sources. The UNEP Governing Council has concluded that there is sufficient evidence of significant global adverse impacts from mercury to warrant further international action; and that national, regional and global actions should be initiated as soon as possible to identify populations at risk and to reduce human generated releases. This paper describes the development of, and presents results from, a comprehensive, spatially and temporally resolved inventory of atmospheric mercury emissions from the Australian landmass. Results indicate that the best estimate of total anthropogenic emissions of mercury to the atmosphere in 2006 was 15 ± 5 tonnes. Three industrial sectors contribute substantially to Australian anthropogenic emissions: gold smelting (˜50%, essentially from a single site/operation), coal combustion in power plants (˜15%) and alumina production from bauxite (˜12%). A diverse range of other sectors contribute smaller proportions of the emitted mercury, but industrial emissions account for around 90% of total anthropogenic mercury emissions. The other sectors include other industrial sources (mining, smelting, and cement production) and the use of products containing mercury. It is difficult to determine historical trends in mercury emissions given the large uncertainties in the data. Estimates for natural and re-emitted emissions from soil, water, vegetation and fires are made using meteorological models, satellite observations of land cover and soil and vegetation type, fuel loading, fire scars and emission factors which account for the effects of temperature, insolation and other environmental variables. These natural and re-emitted sources comfortably exceed the anthropogenic emissions, and comprise 4-12 tonnes per year from vegetation, 70-210 tonnes per year from soils, and 21-63 tonnes

Environmental consequences of atmosphereic krypton-85. Final report, January 1, 1977-September 30, 1979

International Nuclear Information System (INIS)

Boeck, W.L.

1979-01-01

Krypton-85 is a radioactive inert gas produced during normal operations of the nuclear fuel cycle. The quantities of krypton-85, that will be produced in the next century, are sufficient, if released, to alter the electrical state of the atmosphere. The principal hypothesis is that an anthropogenic alteration of the electric state of the atmosphere could alter other meterological phenomena and lead to significant environmental impacts. The goal of this project was to explore some areas of basic science related to the evaluation of that hypothesis. The approach was primarily theoretical. The following topics were addressed: a first approximation model to estimate the effects of krypton-85 on the electrical state of the atmosphere; an analysis of the pathways between krypton-85 production and the atmosphere; an analytical model for fair weather atmospheric electricity; and a dipole model for atmospheric electricity. The results will provide a framework on which detailed models can be built. The results should provide better understanding of some topics in atmospheric electricity

Influence of anthropogenic alterations on geomorphic response to climate variations and change in San Francisco Bay-Delta and watershed

Science.gov (United States)

Florsheim, J.L.; Dettinger, M.D.

2004-01-01

Global warming and attendant sea-level rise may soon impact geomorphic processes in the Sacramento-San Joaquin River and San Francisco Bay Delta systems. During the past two centuries, dramatic anthropogenic changes in sediment supply and pervasive structural controls on rivers and floodplains have altered geomorphic responses to floods throughout a zone that extends upstream from tidally influenced areas to dams that regulate flow. Current geomorphic responses to floods differ from natural responses due to historical actions that concentrated the pre-disturbance multiple-channel and flood-basin system into single channels isolated by levees from increasingly developed floodplains and flood bypass channels, altered flow and sediment regimes, and caused subsidence of leveed Delta Islands. A review of historic and current geomorphic responses to floods illustrates the dominance of structural controls on geomorphic changes in the lowland part of the Sacramento-San Joaquin system. Current climate-change projections for CA suggest that the total volume of snowmelt runoff that may be shifted from spring and added to winter flows is roughly 5 maf/yr, similar to the volume currently available for flood storage in Sierra Nevadan reservoirs. Changes in timing of reservoir releases to accommodate these changes could add to either the magnitude or duration of winter flood peaks, each causing different geomorphic responses. Increased wintertime flows that accompany already large floods could increase overbank flood extent, erosion, and sedimentation, or alternatively increase the depth and strength of confined flows and increase the risk of levee failures. Runoff released from reservoirs as a relatively constant addition to winter baseflow would increase the duration of bankfull or possibly "levee-full" flows. This scenario could lead to bank and levee failure through increased saturation and seepage erosion. Projected sea level rise of 1-2 m would compound vulnerability of

Social vulnerability in the flood-prone anthropogenic landscape of Northern Italy

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Roder, Giulia; Sofia, Giulia; Wu, Zhifeng; Tarolli, Paolo

2017-04-01

The practices for reducing the impacts of floods are becoming more and more advanced, centred to the communities and reached out to vulnerable populations. Vulnerable individuals are characterised by different social and economic attributes that can alter their capacity to cope with disaster events. The Social Vulnerability Index (Cutter et al. 2003) provides an empirical basis to compare social variances in different spatial scenarios and environmental threats. This methodology has been readjusted to the flood-prone anthropogenic landscape of Northern Italy adapted to the societal and historical construction of this area. In fact, the fifteen census variables used have been contextualised by examining the economic crisis, the modification of the labour force, the gendered life expectancy, the immigration among much more. At a general consideration, the unstable economic status, the population growth, age, and ethnicity are the major social attributes affecting the residents of the floodplain. The cluster analysis performed by the calculation of univariate LISA ratifies the spatial distribution of the index (Moran's I of 0.39 showing a positive correlation) finding the main high-high clusters in the Western and the outlet of the Po River basin. This basin includes one-third of the Italian population and this anthropogenic footprint has consistently modified the basin natural and geological environment (Carminati and Martinelli 2002) to the point that the hydraulic system will be dramatically altered in the future (Dankers and Feyen 2008). The spatial identification and the inclusion of vulnerable people into the risk management planning process have been widely discussed in the Sendai Framework for Disaster Risk Reduction. For this reason, we analysed the flood risk resulting from the combination of high vulnerable areas with the highest flood hazard scenario. The hazard map, finalised in May 2015, has been provided by ISPRA Institute with a three-class flood

Anthropogenic changes in sodium affect neural and muscle development in butterflies

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Snell-Rood, Emilie C.; Espeset, Anne; Boser, Christopher J.; White, William A.; Smykalski, Rhea

2014-01-01

The development of organisms is changing drastically because of anthropogenic changes in once-limited nutrients. Although the importance of changing macronutrients, such as nitrogen and phosphorus, is well-established, it is less clear how anthropogenic changes in micronutrients will affect organismal development, potentially changing dynamics of selection. We use butterflies as a study system to test whether changes in sodium availability due to road salt runoff have significant effects on the development of sodium-limited traits, such as neural and muscle tissue. We first document how road salt runoff can elevate sodium concentrations in the tissue of some plant groups by 1.5–30 times. Using monarch butterflies reared on roadside- and prairie-collected milkweed, we then show that road salt runoff can result in increased muscle mass (in males) and neural investment (in females). Finally, we use an artificial diet manipulation in cabbage white butterflies to show that variation in sodium chloride per se positively affects male flight muscle and female brain size. Variation in sodium not only has different effects depending on sex, but also can have opposing effects on the same tissue: across both species, males increase investment in flight muscle with increasing sodium, whereas females show the opposite pattern. Taken together, our results show that anthropogenic changes in sodium availability can affect the development of traits in roadside-feeding herbivores. This research suggests that changing micronutrient availability could alter selection on foraging behavior for some roadside-developing invertebrates. PMID:24927579

Anthropogenic changes in sodium affect neural and muscle development in butterflies.

Science.gov (United States)

Snell-Rood, Emilie C; Espeset, Anne; Boser, Christopher J; White, William A; Smykalski, Rhea

2014-07-15

The development of organisms is changing drastically because of anthropogenic changes in once-limited nutrients. Although the importance of changing macronutrients, such as nitrogen and phosphorus, is well-established, it is less clear how anthropogenic changes in micronutrients will affect organismal development, potentially changing dynamics of selection. We use butterflies as a study system to test whether changes in sodium availability due to road salt runoff have significant effects on the development of sodium-limited traits, such as neural and muscle tissue. We first document how road salt runoff can elevate sodium concentrations in the tissue of some plant groups by 1.5-30 times. Using monarch butterflies reared on roadside- and prairie-collected milkweed, we then show that road salt runoff can result in increased muscle mass (in males) and neural investment (in females). Finally, we use an artificial diet manipulation in cabbage white butterflies to show that variation in sodium chloride per se positively affects male flight muscle and female brain size. Variation in sodium not only has different effects depending on sex, but also can have opposing effects on the same tissue: across both species, males increase investment in flight muscle with increasing sodium, whereas females show the opposite pattern. Taken together, our results show that anthropogenic changes in sodium availability can affect the development of traits in roadside-feeding herbivores. This research suggests that changing micronutrient availability could alter selection on foraging behavior for some roadside-developing invertebrates.

Modeling climatic effects of anthropogenic CO2 emissions: Unknowns and uncertainties

Science.gov (United States)

Soon, W.; Baliunas, S.; Idso, S.; Kondratyev, K. Ya.; Posmentier, E. S.

2001-12-01

A likelihood of disastrous global environmental consequences has been surmised as a result of projected increases in anthropogenic greenhouse gas emissions. These estimates are based on computer climate modeling, a branch of science still in its infancy despite recent, substantial strides in knowledge. Because the expected anthropogenic climate forcings are relatively small compared to other background and forcing factors (internal and external), the credibility of the modeled global and regional responses rests on the validity of the models. We focus on this important question of climate model validation. Specifically, we review common deficiencies in general circulation model calculations of atmospheric temperature, surface temperature, precipitation and their spatial and temporal variability. These deficiencies arise from complex problems associated with parameterization of multiply-interacting climate components, forcings and feedbacks, involving especially clouds and oceans. We also review examples of expected climatic impacts from anthropogenic CO2 forcing. Given the host of uncertainties and unknowns in the difficult but important task of climate modeling, the unique attribution of observed current climate change to increased atmospheric CO2 concentration, including the relatively well-observed latest 20 years, is not possible. We further conclude that the incautious use of GCMs to make future climate projections from incomplete or unknown forcing scenarios is antithetical to the intrinsically heuristic value of models. Such uncritical application of climate models has led to the commonly-held but erroneous impression that modeling has proven or substantiated the hypothesis that CO2 added to the air has caused or will cause significant global warming. An assessment of the positive skills of GCMs and their use in suggesting a discernible human influence on global climate can be found in the joint World Meteorological Organisation and United Nations

Desert dust and anthropogenic aerosol interactions in the Community Climate System Model coupled-carbon-climate model

Directory of Open Access Journals (Sweden)

N. Mahowald

2011-02-01

Full Text Available Coupled-carbon-climate simulations are an essential tool for predicting the impact of human activity onto the climate and biogeochemistry. Here we incorporate prognostic desert dust and anthropogenic aerosols into the CCSM3.1 coupled carbon-climate model and explore the resulting interactions with climate and biogeochemical dynamics through a series of transient anthropogenic simulations (20th and 21st centuries and sensitivity studies. The inclusion of prognostic aerosols into this model has a small net global cooling effect on climate but does not significantly impact the globally averaged carbon cycle; we argue that this is likely to be because the CCSM3.1 model has a small climate feedback onto the carbon cycle. We propose a mechanism for including desert dust and anthropogenic aerosols into a simple carbon-climate feedback analysis to explain the results of our and previous studies. Inclusion of aerosols has statistically significant impacts on regional climate and biogeochemistry, in particular through the effects on the ocean nitrogen cycle and primary productivity of altered iron inputs from desert dust deposition.

Environmental impact on morphological and anatomical structure of ...

African Journals Online (AJOL)

Morphological and anatomical structure of Tansy (Tanacetum vulgare L.) from two specific locations in one town, depending on environmental conditions, were carried out: anthropogenic Ada Huja (polluted zone) and non anthropogenic Topcider park (unpolluted). Study included the diferences in the structure of leaves, ...

Anthropogenic CO2 in the ocean

Directory of Open Access Journals (Sweden)

Tsung-Hung Peng

2005-06-01

Full Text Available The focus of this review article is on the anthropogenic CO2 taken up by the ocean. There are several methods of identifying the anthropogenic CO2 signal and quantifying its inventory in the ocean. The ?C* method is most frequently used to estimate the global distribution of anthropogenic CO2 in the ocean. Results based on analysis of the dataset obtained from the comprehensive surveys of inorganic carbon distribution in the world oceans in the 1990s are given. These surveys were jointly conducted during the World Ocean Circulation Experiment (WOCE and the Joint Global Ocean Flux Study (JGOFS. This data set consists of 9618 hydrographic stations from a total of 95 cruises, which represents the most accurate and comprehensive view of the distribution of inorganic carbon in the global ocean available today. The increase of anthropogenic CO2 in the ocean during the past few decades is also evaluated using direct comparison of results from repeat surveys and using statistical method of Multi-parameter Linear Regression (MLR. The impact of increasing oceanic anthropogenic CO2 on the calcium carbonate system in the ocean is reviewed briefly as well. Extensive studies of CaCO3 dissolution as a result of increasing anthropogenic CO2 in the ocean have revealed several distinct oceanic regions where the CaCO3 undersaturation zone has expanded.

Forecasting the relative influence of environmental and anthropogenic stressors on polar bears

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Atwood, Todd C.; Marcot, Bruce G.; Douglas, David C.; Amstrup, Steven C.; Rode, Karyn D.; Durner, George M.; Bromaghin, Jeffrey F.

2016-01-01

Effective conservation planning requires understanding and ranking threats to wildlife populations. We developed a Bayesian network model to evaluate the relative influence of environmental and anthropogenic stressors, and their mitigation, on the persistence of polar bears (Ursus maritimus). Overall sea ice conditions, affected by rising global temperatures, were the most influential determinant of population outcomes. Accordingly, unabated rise in atmospheric greenhouse gas (GHG) concentrations was the dominant influence leading to worsened population outcomes, with polar bears in three of four ecoregions reaching a dominant probability of decreased or greatly decreased by the latter part of this century. Stabilization of atmospheric GHG concentrations by mid-century delayed the greatly reduced state by ≈25 yr in two ecoregions. Prompt and aggressive mitigation of emissions reduced the probability of any regional population becoming greatly reduced by up to 25%. Marine prey availability, linked closely to sea ice trend, had slightly less influence on outcome state than sea ice availability itself. Reduced mortality from hunting and defense of life and property interactions resulted in modest declines in the probability of a decreased or greatly decreased population outcome. Minimizing other stressors such as trans-Arctic shipping, oil and gas exploration, and contaminants had a negligible effect on polar bear outcomes, although the model was not well-informed with respect to the potential influence of these stressors. Adverse consequences of loss of sea ice habitat became more pronounced as the summer ice-free period lengthened beyond four months, which could occur in most of the Arctic basin after mid-century if GHG emissions are not promptly reduced. Long-term conservation of polar bears would be best supported by holding global mean temperature to ≤ 2°C above preindustrial levels. Until further sea ice loss is stopped, management of other stressors may

Estimating animal mortality from anthropogenic hazards

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Carcass searches are a common method for studying the risk of anthropogenic hazards to wildlife, including non-target poisoning and collisions with anthropogenic structures. Typically, numbers of carcasses found must be corrected for scavenging rates and imperfect detection. Para...

Responses of Surface Ozone Air Quality to Anthropogenic Nitrogen Deposition

Science.gov (United States)

Zhang, L.; Zhao, Y.; Tai, A. P. K.; Chen, Y.; Pan, Y.

2017-12-01

Human activities have substantially increased atmospheric deposition of reactive nitrogen to the Earth's surface, inducing unintentional effects on ecosystems with complex environmental and climate consequences. One consequence remaining unexplored is how surface air quality might respond to the enhanced nitrogen deposition through surface-atmosphere exchange. We combine a chemical transport model (GEOS-Chem) and a global land model (Community Land Model) to address this issue with a focus on ozone pollution in the Northern Hemisphere. We consider three processes that are important for surface ozone and can be perturbed by addition of atmospheric deposited nitrogen: emissions of biogenic volatile organic compounds (VOCs), ozone dry deposition, and soil nitrogen oxide (NOx) emissions. We find that present-day anthropogenic nitrogen deposition (65 Tg N a-1 to the land), through enhancing plant growth (represented as increases in vegetation leaf area index (LAI) in the model), could increase surface ozone from increased biogenic VOC emissions, but could also decrease ozone due to higher ozone dry deposition velocities. Meanwhile, deposited anthropogenic nitrogen to soil enhances soil NOx emissions. The overall effect on summer mean surface ozone concentrations show general increases over the globe (up to 1.5-2.3 ppbv over the western US and South Asia), except for some regions with high anthropogenic NOx emissions (0.5-1.0 ppbv decreases over the eastern US, Western Europe, and North China). We compare the surface ozone changes with those driven by the past 20-year climate and historical land use changes. We find that the impacts from anthropogenic nitrogen deposition can be comparable to the climate and land use driven surface ozone changes at regional scales, and partly offset the surface ozone reductions due to land use changes reported in previous studies. Our study emphasizes the complexity of biosphere-atmosphere interactions, which can have important

Environmental estrogen(s) induced swimming behavioural alterations in adult zebrafish (Danio rerio).

Science.gov (United States)

Goundadkar, Basavaraj B; Katti, Pancharatna

2017-09-01

The present study is an attempt to investigate the effects of long-term (75days) exposure to environmental estrogens (EE) on the swimming behaviour of zebrafish (Danio rerio). Adult zebrafish were exposed semi-statically to media containing commonly detected estrogenic water contaminants (EE2, DES and BPA) at a concentration (5ng/L) much lower than environmentally recorded levels. Time spent in swimming, surface preference, patterns and path of swimming were recorded (6mins) for each fish using two video cameras on day 15, 30 60 and 75. Video clips were analysed using a software program. Results indicate that chronic exposure to EE leads to increased body weight and size of females, reduced (Pswimming time, delay in latency, increased (P<0.05) immobility, erratic movements and freezing episodes. We conclude that estrogenic contamination of natural aquatic systems induces alterations in locomotor behaviour and associated physiological disturbances in inhabitant fish fauna. Copyright © 2017 Elsevier B.V. All rights reserved.

Environmental Impact from Outdoor/Environmental Education Programs: Effects of Frequent Stream Classes on Aquatic Macroinvertebrates

Science.gov (United States)

Bossley, Jon P.

2016-01-01

Environmental stewardship is an underlying theme in outdoor education (OE) and environmental education (EE), but maintaining natural areas in a sustainable balance between conservation and preservation requires knowledge about how natural areas respond to anthropogenic disturbance. My five-part study investigated the effects of disturbance on…

Environmental assessment of the area surrounding Dam Rio Verde - Parana/Brazil. An overview of environmental geomorphology.

Science.gov (United States)

Garcia, Claudia Moreira; Carrijo, Beatriz Rodrigues; Sessegolo, Gisele; Passos, Everton

2012-04-01

This paper presents a brief essay on the situation in which the environment of the dam of the Rio Verde Basin-Parana, from the vision of environmental geomorphology. The area is located between the cities of Campo Magro and Campo Largo, Paraná plateau in the first part of theAlto Iguaçu basin. This study aims to raise the concepts relating to environmental geomorphology, to identify the anthropogenic impacts caused in the reservoir areas, identify the environmental compartments found around the dam and characterize the geologic and physiographic region. It was found that the area has intense anthropogenic influence, as urban growth is present in areas and wavy and rough terrain, subject to mass movements and floods. Besides these aspects, the use of land for agriculture contributes to fragility of the area.

Climate forcing by anthropogenic aerosols

Energy Technology Data Exchange (ETDEWEB)

Charlson, R J; Schwartz, S E; Hales, J M; Cess, R D; Coakley, Jr, J A; Hansen, J E; Hofmann, D J [University of Washington, Seattle, WA (USA). Inst. for Environmental Studies, Dept. of Atmospheric Sciences

1992-01-24

Although long considered to be of marginal importance to global climate change, tropospheric aerosol contributes substantially to radiative forcing, and anthropogenic sulfate aerosol in particular has imposed a major perturbation to this forcing. Both the direct scattering of short wavelength solar radiation and the modification of the shortwave reflective properties of clouds by sulfate aerosol particles increase planetary albedo, thereby exerting a cooling influence on the planet. Current climate forcing due to anthropogenic sulfate is estimated to be -1 to -2 watts per square metre, globally averaged. This perturbation is comparable in magnitude to current anthropogenic greenhouse gas forcing but opposite in sign. Thus, the aerosol forcing has likely offset global greenhouse warming to a substantial degree. However, differences in geographical and seasonal distributions of these forcings preclude any simple compensation. Aerosol effects must be taken into account in evaluating anthropogenic influences on past, current, and projected future climate and in formulating policy regarding controls on emission of greenhouse gases and sulfur dioxide. Resolution of such policy issues requires integrated research on the magnitude and geographical distribution of aerosol climate forcing and on the controlling chemical and physical processes. 73 refs., 4 figs., 2 tabs.

Climate forcing by anthropogenic aerosols.

Science.gov (United States)

Charlson, R J; Schwartz, S E; Hales, J M; Cess, R D; Coakley, J A; Hansen, J E; Hofmann, D J

1992-01-24

Although long considered to be of marginal importance to global climate change, tropospheric aerosol contributes substantially to radiative forcing, and anthropogenic sulfate aerosol in particular has imposed a major perturbation to this forcing. Both the direct scattering of shortwavelength solar radiation and the modification of the shortwave reflective properties of clouds by sulfate aerosol particles increase planetary albedo, thereby exerting a cooling influence on the planet. Current climate forcing due to anthropogenic sulfate is estimated to be -1 to -2 watts per square meter, globally averaged. This perturbation is comparable in magnitude to current anthropogenic greenhouse gas forcing but opposite in sign. Thus, the aerosol forcing has likely offset global greenhouse warming to a substantial degree. However, differences in geographical and seasonal distributions of these forcings preclude any simple compensation. Aerosol effects must be taken into account in evaluating anthropogenic influences on past, current, and projected future climate and in formulating policy regarding controls on emission of greenhouse gases and sulfur dioxide. Resolution of such policy issues requires integrated research on the magnitude and geographical distribution of aerosol climate forcing and on the controlling chemical and physical processes.

Anthropogenic range contractions bias species climate change forecasts

Science.gov (United States)

Faurby, Søren; Araújo, Miguel B.

2018-03-01

Forecasts of species range shifts under climate change most often rely on ecological niche models, in which characterizations of climate suitability are highly contingent on the species range data used. If ranges are far from equilibrium under current environmental conditions, for instance owing to local extinctions in otherwise suitable areas, modelled environmental suitability can be truncated, leading to biased estimates of the effects of climate change. Here we examine the impact of such biases on estimated risks from climate change by comparing models of the distribution of North American mammals based on current ranges with ranges accounting for historical information on species ranges. We find that estimated future diversity, almost everywhere, except in coastal Alaska, is drastically underestimated unless the full historical distribution of the species is included in the models. Consequently forecasts of climate change impacts on biodiversity for many clades are unlikely to be reliable without acknowledging anthropogenic influences on contemporary ranges.

Anthropogenic climate change drives shift and shuffle in North Atlantic phytoplankton communities.

Science.gov (United States)

Barton, Andrew D; Irwin, Andrew J; Finkel, Zoe V; Stock, Charles A

2016-03-15

Anthropogenic climate change has shifted the biogeography and phenology of many terrestrial and marine species. Marine phytoplankton communities appear sensitive to climate change, yet understanding of how individual species may respond to anthropogenic climate change remains limited. Here, using historical environmental and phytoplankton observations, we characterize the realized ecological niches for 87 North Atlantic diatom and dinoflagellate taxa and project changes in species biogeography between mean historical (1951-2000) and future (2051-2100) ocean conditions. We find that the central positions of the core range of 74% of taxa shift poleward at a median rate of 12.9 km per decade (km⋅dec(-1)), and 90% of taxa shift eastward at a median rate of 42.7 km⋅dec(-1) The poleward shift is faster than previously reported for marine taxa, and the predominance of longitudinal shifts is driven by dynamic changes in multiple environmental drivers, rather than a strictly poleward, temperature-driven redistribution of ocean habitats. A century of climate change significantly shuffles community composition by a basin-wide median value of 16%, compared with seasonal variations of 46%. The North Atlantic phytoplankton community appears poised for marked shift and shuffle, which may have broad effects on food webs and biogeochemical cycles.

The Chukchi Sea zoobenthos: contemporary conditions and trends in anthropogenic influence.

Directory of Open Access Journals (Sweden)

Kirievskaya Dubrava

2017-06-01

Full Text Available The Chukchi Sea is a key region where rapid changes of the Arctic environment have been observed recently. Benthos of the Chukchi Sea is a sensitive indicator of these changes. In addition, the benthos can be used as an indicator of the anthropogenic load on the marine environment. A lot of researches have been conducted in the different parts of the Chukchi Sea. In this paper we summarized all the data collected for the last 30 years to evaluate contemporary conditions of the Chukchi Sea benthos as well as to discuss a potential response of the benthic ecosystem to the anthropogenic load. The Chukchi Sea zoobenthos is characterized by relatively high biodiversity compared to the seas of the western Arctic Ocean. The spatial distribution of zoobenthos is non-uniform. It is caused by a lot of factors: depth, bottom and sediment temperature, geochemical structure of the sediments, hydrodynamics, etc. Present environmental conditions of the Chukchi Sea biota can be considered to be close to the average long-term norms. By the reason of climate change scientists started to observe northing displacement of subarctic and temperate species of the benthic ecosystem. The Chukchi Sea is still included into the area with low anthropogenic pressure. The main potential threat for the Chukchi sea benthos results from continued oil and gas exploration and sea transport. For example, benthos around oil-wells (the Burger and the Klondike contains pollutants at a high concentration. The risk of rising anthropogenic load on the Chukchi Sea ecosystem poses the problem to additionally identify vulnerable areas of increased ecological significance for later receiving conservation status.

Aquatic subsidies transport anthropogenic nitrogen to riparian spiders

Energy Technology Data Exchange (ETDEWEB)

Akamatsu, Fumikazu, E-mail: f-akamt55@pwri.go.jp [Department of Environmental Sciences, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan); Toda, Hideshige [Department of Environmental Sciences, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan)

2011-05-15

Stable nitrogen isotopic composition ({delta}{sup 15}N) of aquatic biota increases with anthropogenic N inputs such as sewage and livestock waste downstream. Increase in {delta}{sup 15}N of riparian spiders downstream may reflect the anthropogenic pollution exposure through predation on aquatic insects. A two-source mixing model based on stable carbon isotopic composition showed the greatest dependence on aquatic insects (84%) by horizontal web-building spiders, followed by intermediate (48%) and low (31%) dependence by cursorial and vertical web-building spiders, respectively. The spider body size was negatively correlated with the dietary proportion of aquatic insects and spider {delta}{sup 15}N. The aquatic subsidies transported anthropogenic N to smaller riparian spiders downstream. This transport of anthropogenic N was regulated by spider's guild designation and body size. - Highlights: > {delta}{sup 15}N of aquatic insects increases downstream with anthropogenic nitrogen inputs. > {delta}{sup 15}N of riparian spiders increases with a high dietary proportion of aquatic insects and smaller spider body size. > The aquatic subsidies transport anthropogenic nitrogen to smaller riparian spiders downstream. - Smaller spiders assimilate anthropogenic nitrogen through the predation on aquatic subsides.

Aquatic subsidies transport anthropogenic nitrogen to riparian spiders

International Nuclear Information System (INIS)

Akamatsu, Fumikazu; Toda, Hideshige

2011-01-01

Stable nitrogen isotopic composition (δ 15 N) of aquatic biota increases with anthropogenic N inputs such as sewage and livestock waste downstream. Increase in δ 15 N of riparian spiders downstream may reflect the anthropogenic pollution exposure through predation on aquatic insects. A two-source mixing model based on stable carbon isotopic composition showed the greatest dependence on aquatic insects (84%) by horizontal web-building spiders, followed by intermediate (48%) and low (31%) dependence by cursorial and vertical web-building spiders, respectively. The spider body size was negatively correlated with the dietary proportion of aquatic insects and spider δ 15 N. The aquatic subsidies transported anthropogenic N to smaller riparian spiders downstream. This transport of anthropogenic N was regulated by spider's guild designation and body size. - Highlights: → δ 15 N of aquatic insects increases downstream with anthropogenic nitrogen inputs. → δ 15 N of riparian spiders increases with a high dietary proportion of aquatic insects and smaller spider body size. → The aquatic subsidies transport anthropogenic nitrogen to smaller riparian spiders downstream. - Smaller spiders assimilate anthropogenic nitrogen through the predation on aquatic subsides.

Quarrying: an anthropogenic geomorphological approach

International Nuclear Information System (INIS)

David, L.

2008-01-01

The study intends to give an introduction to the significance of quarrying from the point of view of anthropogenic geomorphology, indicating the level of surface forming due to the mining of mineral raw materials. The significance of this topic is supported by the existence of the so-called 'mining landscapes' that emerged since to the 19 th century. Authors focus on the geomorphic impact of quarrying with special emphasis on factors influencing its spatial distribution, as well as on the characteristics and classification of surface features produced by quarrying, providing an overview of the most important excavated and accumulated forms and form components, on the macro, meso and micro scales. Finally, international and Hungarian case studies illustrate some aspects of the opening and after-use of mining sites in order to observe how abandoned quarries can be turned into 'environmental values', and used as possible sites for exhibitions or for regional and tourism development projects. (author)

Environmental conditions influence tissue regeneration rates in scleractinian corals.

Science.gov (United States)

Sabine, Alexis M; Smith, Tyler B; Williams, Dana E; Brandt, Marilyn E

2015-06-15

Natural and anthropogenic factors may influence corals' ability to recover from partial mortality. To examine how environmental conditions affect lesion healing, we assessed several water quality parameters and tissue regeneration rates in corals at six reefs around St. Thomas, US Virgin Islands. We hypothesized that sites closer to developed areas would have poor water quality due to proximity to anthropogenic stresses, which would impede tissue regeneration. We found that water flow and turbidity most strongly influenced lesion recovery rates. The most impacted site, with high turbidity and low flow, recovered almost three times slower than the least impacted site, with low turbidity, high flow, and low levels of anthropogenic disturbance. Our results illustrate that in addition to lesion-specific factors known to affect tissue regeneration, environmental conditions can also control corals' healing rates. Resource managers can use this information to protect low-flow, turbid nearshore reefs by minimizing sources of anthropogenic stress. Copyright © 2015 Elsevier Ltd. All rights reserved.

Benthic communities under anthropogenic pressure show resilience across the Quaternary.

Science.gov (United States)

Martinelli, Julieta C; Soto, Luis P; González, Jorge; Rivadeneira, Marcelo M

2017-09-01

The Southeast Pacific is characterized by rich upwelling systems that have sustained and been impacted by human groups for at least 12 ka. Recent fishing and aquaculture practices have put a strain on productive coastal ecosystems from Tongoy Bay, in north-central Chile. We use a temporal baseline to determine whether potential changes to community structure and composition over time are due to anthropogenic factors, natural climatic variations or both. We compiled a database ( n  = 33 194) with mollusc species abundances from the Mid-Pleistocene, Late Pleistocene, Holocene, dead shell assemblages and live-sampled communities. Species richness was not significantly different, neither were diversity and evenness indices nor rank abundance distributions. There is, however, an increase in relative abundance for the cultured scallop Argopecten , while the previously dominant clam Mulinia is locally very rare. Results suggest that impacts from both natural and anthropogenic stressors need to be better understood if benthic resources are to be preserved. These findings provide the first Pleistocene temporal baseline for the south Pacific that shows that this highly productive system has had the ability to recover from past alterations, suggesting that if monitoring and management practices continue to be implemented, moderately exploited communities from today have hopes for recovery.

Benthic communities under anthropogenic pressure show resilience across the Quaternary

Science.gov (United States)

Martinelli, Julieta C.; Soto, Luis P.; González, Jorge; Rivadeneira, Marcelo M.

2017-09-01

The Southeast Pacific is characterized by rich upwelling systems that have sustained and been impacted by human groups for at least 12 ka. Recent fishing and aquaculture practices have put a strain on productive coastal ecosystems from Tongoy Bay, in north-central Chile. We use a temporal baseline to determine whether potential changes to community structure and composition over time are due to anthropogenic factors, natural climatic variations or both. We compiled a database (n = 33 194) with mollusc species abundances from the Mid-Pleistocene, Late Pleistocene, Holocene, dead shell assemblages and live-sampled communities. Species richness was not significantly different, neither were diversity and evenness indices nor rank abundance distributions. There is, however, an increase in relative abundance for the cultured scallop Argopecten, while the previously dominant clam Mulinia is locally very rare. Results suggest that impacts from both natural and anthropogenic stressors need to be better understood if benthic resources are to be preserved. These findings provide the first Pleistocene temporal baseline for the south Pacific that shows that this highly productive system has had the ability to recover from past alterations, suggesting that if monitoring and management practices continue to be implemented, moderately exploited communities from today have hopes for recovery.

Identifying anthropogenic uranium compounds using soft X-ray near-edge absorption spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Ward, Jesse D.; Bowden, Mark; Tom Resch, C.; Eiden, Gregory C.; Pemmaraju, C. D.; Prendergast, David; Duffin, Andrew M.

2017-01-01

Uranium ores mined for industrial use are typically acid-leached to produce yellowcake and then converted into uranium halides for enrichment and purification. These anthropogenic chemical forms of uranium are distinct from their mineral counterparts. The purpose of this study is to use soft X-ray absorption spectroscopy to characterize several common anthropogenic uranium compounds important to the nuclear fuel cycle. Non-destructive chemical analyses of these compounds is important for process and environmental monitoring and X-ray absorption techniques have several advantages in this regard, including element-specificity, chemical sensitivity, and high spectral resolution. Oxygen K-edge spectra were collected for uranyl nitrate, uranyl fluoride, and uranyl chloride, and fluorine K-edge spectra were collected for uranyl fluoride and uranium tetrafluoride. Interpretation of the data is aided by comparisons to calculated spectra. These compounds have unique spectral signatures that can be used to identify unknown samples.

Future of African terrestrial biodiversity and ecosystems under anthropogenic climate change

Science.gov (United States)

Midgley, Guy F.; Bond, William J.

2015-09-01

Projections of ecosystem and biodiversity change for Africa under climate change diverge widely. More than other continents, Africa has disturbance-driven ecosystems that diversified under low Neogene CO2 levels, in which flammable fire-dependent C4 grasses suppress trees, and mega-herbivore action alters vegetation significantly. An important consequence is metastability of vegetation state, with rapid vegetation switches occurring, some driven by anthropogenic CO2-stimulated release of trees from disturbance control. These have conflicting implications for biodiversity and carbon sequestration relevant for policymakers and land managers. Biodiversity and ecosystem change projections need to account for both disturbance control and direct climate control of vegetation structure and function.

Variability in fluvial geomorphic response to anthropogenic disturbance

Science.gov (United States)

Verstraeten, Gert; Broothaerts, Nils; Van Loo, Maarten; Notebaert, Bastiaan; D'Haen, Koen; Dusar, Bert; De Brue, Hanne

2017-10-01

Humans have greatly impacted the processes and intensities of erosion, sediment transport and storage since the introduction of agriculture. In many regions around the world, accelerated floodplain sedimentation can be related to increases in human pressure on the environment. However, the relation between the intensity of anthropogenic disturbance and the magnitude of change in fluvial sediment dynamics is not straightforward and often non-linear. Here, we review a number of case studies from contrasting environmental settings in the European loess belt, the Eastern Mediterranean mountain ranges and the eastern USA. Detailed field-based sediment archive studies and sediment budgets covering time periods ranging from 200 to over 5000 year, as well as the use of pollen and sediment provenance techniques, show that no overarching concept of changes in floodplain sedimentation following anthropogenic disturbance can be established. Slope-channel (dis)connectivity controls the existence of thresholds or tipping points that need to be crossed before significant changes in downstream sediment dynamics are recorded following human impact. This coupling can be related to characteristics of human pressure such as its duration, intensity and spatial patterns, but also to the geomorphic and tectonic setting. Furthermore, internal feedback mechanisms, such as those between erosion and soil thickness, further complicate the story. All these factors controlling the propagation of sediment from eroding hillslopes to river channels vary between regions. Hence, only unique patterns of fluvial geomorphic response can be identified. As a result, unravelling the human impact from current-day sediment archives and predicting the impact of future human disturbances on fluvial sediment dynamics remain a major challenge. This has important implications for interpreting contemporary sediment yields as well as downstream sediment records in large floodplains, deltas and the marine

Real-time observational evidence of changing Asian dust morphology with the mixing of heavy anthropogenic pollution

Science.gov (United States)

Pan, X.; Uno, I.; Wang, Z.; Nishizawa, T.; Sugimoto, N.; Yamamoto, S.; Kobayashi, H.; Sun, Y.; Fu, P.; Tang, X.; Wang, Z.

2017-12-01

Natural mineral dust and heavy anthropogenic pollution and its complex interactions cause significant environmental problems in East Asia. Due to restrictions of observing technique, real-time morphological change in Asian dust particles owing to coating process of anthropogenic pollutants is still statistically unclear. Here, we first used a newly developed, single-particle polarization detector and quantitatively investigate the evolution of the polarization property of backscattering light reflected from dust particle as they were mixing with anthropogenic pollutants in North China. The decrease in observed depolarization ratio is mainly attributed to the decrease of aspect ratio of the dust particles as a result of continuous coating processes. Hygroscopic growth of Calcium nitrate (Ca(NO3)2) on the surface of the dust particles played a vital role, particularly when they are stagnant in the polluted region with high RH conditions. Reliable statistics highlight the significant importance of internally mixed, `quasi-spherical' Asian dust particles, which markedly act as cloud condensation nuclei and exert regional climate change.

Better, but good enough? Indicators for absolute environmental sustainability in a life cycle perspective

DEFF Research Database (Denmark)

Bjørn, Anders; Richardson, Katherine

An increasing focus on sustainability has led to proliferation of the use of environmental indicators to guide various types of decisions, from individual consumer choices to policy making at the national, regional and global scale. Most environmental indicators are relative, meaning that quantif......An increasing focus on sustainability has led to proliferation of the use of environmental indicators to guide various types of decisions, from individual consumer choices to policy making at the national, regional and global scale. Most environmental indicators are relative, meaning...... that quantified environmental interferences of a studied anthropogenic system (a product, a company, a city, etc.) are compared to those of chosen anthropogenic systems of reference. The use of relative indicators can give the impression that societies are moving towards environmental sustainability when...... that society-nature interactions in many cases are environmentally unsustainable and that the level of unsustainability may be increasing over time. A clear rationale therefore exists for developing and using absolute environmental sustainability indicators (AESI) that not only can identify the anthropogenic...

Anthropogenic Space Weather

Science.gov (United States)

Gombosi, T. I.; Baker, D. N.; Balogh, A.; Erickson, P. J.; Huba, J. D.; Lanzerotti, L. J.

2017-11-01

Anthropogenic effects on the space environment started in the late 19th century and reached their peak in the 1960s when high-altitude nuclear explosions were carried out by the USA and the Soviet Union. These explosions created artificial radiation belts near Earth that resulted in major damages to several satellites. Another, unexpected impact of the high-altitude nuclear tests was the electromagnetic pulse (EMP) that can have devastating effects over a large geographic area (as large as the continental United States). Other anthropogenic impacts on the space environment include chemical release experiments, high-frequency wave heating of the ionosphere and the interaction of VLF waves with the radiation belts. This paper reviews the fundamental physical process behind these phenomena and discusses the observations of their impacts.

Anthropogenic combustion iron as a complex climate forcer.

Science.gov (United States)

Matsui, Hitoshi; Mahowald, Natalie M; Moteki, Nobuhiro; Hamilton, Douglas S; Ohata, Sho; Yoshida, Atsushi; Koike, Makoto; Scanza, Rachel A; Flanner, Mark G

2018-04-23

Atmospheric iron affects the global carbon cycle by modulating ocean biogeochemistry through the deposition of soluble iron to the ocean. Iron emitted by anthropogenic (fossil fuel) combustion is a source of soluble iron that is currently considered less important than other soluble iron sources, such as mineral dust and biomass burning. Here we show that the atmospheric burden of anthropogenic combustion iron is 8 times greater than previous estimates by incorporating recent measurements of anthropogenic magnetite into a global aerosol model. This new estimation increases the total deposition flux of soluble iron to southern oceans (30-90 °S) by 52%, with a larger contribution of anthropogenic combustion iron than dust and biomass burning sources. The direct radiative forcing of anthropogenic magnetite is estimated to be 0.021 W m -2 globally and 0.22 W m -2 over East Asia. Our results demonstrate that anthropogenic combustion iron is a larger and more complex climate forcer than previously thought, and therefore plays a key role in the Earth system.

The sea surface microlayer: biology, chemistry and anthropogenic enrichment

Energy Technology Data Exchange (ETDEWEB)

Hardy, J T

1982-01-01

Recent studies increasingly point to the interface between the world's atmosphere and hydrosphere (the sea-surface microlayer) as an important biological habitat and a collection point for anthropogenic materials. Newly developed sampling techniques collect different qualitative and quantitative fractions of the upper sea surface from depths of less than one micron to several centimeters. The microlayer provides a habitat for a biota, including the larvae of many commercial fishery species, which are often highly enriched in density compared to subsurface water only a few cm below. Common enrichments for bacterioneuston, phytoneuston, and zooneuston are 10/sup 2/-10/sup 4/, 1-10/sup 2/, and 1-10, respectively. The trophic relationships or intergrated functioning of these neustonic communities have not been examined. Surface tension forces provide a physically stable microlayer, but one which is subjected to greater environmental and climatic variation than the water column. A number of poorly understood physical processes control the movement and flux of materials within and through the microlayer. The microlayer is generally coated with a natural organic film of lipid and fatty acid material overlying a polysaccharide protein complex. The microlayer serves as both a source and a sink for materials in the atmosphere and the water column. Among these materials are large quantities of anthropogenic substances which frequently occur at concentrations 10/sup 2/-10/sup 4/ greater than those in the water column. These include plastics, tar lumps, polyaromatic hydrocarbons, chlorinated hydrocarbons, and potentially toxic metals, such as, lead, copper, zinc, and nickel. How the unique processes occurring in the microlayer affect the fate of anthropogenic substances is not yet clear.

Attenuating initial beliefs: increasing the acceptance of anthropogenic climate change information by reflecting on values.

Science.gov (United States)

van Prooijen, Anne-Marie; Sparks, Paul

2014-05-01

Anthropogenic climate change information tends to be interpreted against the backdrop of initial environmental beliefs, which can lead to some people being resistant toward the information. In this article (N = 88), we examined whether self-affirmation via reflection on personally important values could attenuate the impact of initial beliefs on the acceptance of anthropogenic climate change evidence. Our findings showed that initial beliefs about the human impact on ecological stability influenced the acceptance of information only among nonaffirmed participants. Self-affirmed participants who were initially resistant toward the information showed stronger beliefs in the existence of climate change risks and greater acknowledgment that individual efficacy has a role to play in reducing climate change risks than did their nonaffirmed counterparts. © 2013 Society for Risk Analysis.

Environmental context determines community sensitivity of freshwater zooplankton to a pesticide

International Nuclear Information System (INIS)

Stampfli, Nathalie C.; Knillmann, Saskia; Liess, Matthias; Beketov, Mikhail A.

2011-01-01

The environment is currently changing worldwide, and ecosystems are being exposed to multiple anthropogenic pressures. Understanding and consideration of such environmental conditions is required in ecological risk assessment of toxicants, but it remains basically limited. In the present study, we aimed to determine how and to what extent alterations in the abiotic and biotic environmental conditions can alter the sensitivity of a community to an insecticide, as well as its recovery after contamination. We conducted an outdoor microcosm experiment in which zooplankton communities were exposed to the insecticide esfenvalerate (0.03, 0.3, and 3 μg/L) under different regimes of solar radiation and community density, which represented different levels of food availability and competition. We focused on the sensitivity of the entire community and analysed it using multivariate statistical methods, such as principal response curves and redundancy analysis. The results showed that community sensitivity varied markedly between the treatments. In the experimental series with the lowest availability of food and strongest competition significant effects of the insecticide were found at the concentration of 0.03 μg/L. In contrast, in the series with relatively higher food availability and weak competition such effects were detected at 3 μg/L only. However, we did not find significant differences in the community recovery rates between the experimental treatments. These findings indicate that environmental context is more important for ecotoxicological evaluation than assumed previously.

Global Climate Models Intercomparison of Anthropogenic Aerosols Effects on Regional Climate over North Pacific

Science.gov (United States)

Hu, J.; Zhang, R.; Wang, Y.; Ming, Y.; Lin, Y.; Pan, B.

2015-12-01

Aerosols can alter atmospheric radiation and cloud physics, which further exert impacts on weather and global climate. With the development and industrialization of the developing Asian countries, anthropogenic aerosols have received considerable attentions and remain to be the largest uncertainty in the climate projection. Here we assess the performance of two stat-of-art global climate models (National Center for Atmospheric Research-Community Atmosphere Model 5 (CAM5) and Geophysical Fluid Dynamics Laboratory Atmosphere Model 3 (AM3)) in simulating the impacts of anthropogenic aerosols on North Pacific storm track region. By contrasting two aerosol scenarios, i.e. present day (PD) and pre-industrial (PI), both models show aerosol optical depth (AOD) enhanced by about 22%, with CAM5 AOD 40% lower in magnitude due to the long range transport of anthropogenic aerosols. Aerosol effects on the ice water path (IWP), stratiform precipitation, convergence and convection strengths in the two models are distinctive in patterns and magnitudes. AM3 shows qualitatively good agreement with long-term satellite observations, while CAM5 overestimates convection and liquid water path resulting in an underestimation of large-scale precipitation and IWP. Due to coarse resolution and parameterization in convection schemes, both models' performance on convection needs to be improved. Aerosols performance on large-scale circulation and radiative budget are also examined in this study.

Occurrence and sources of natural and anthropogenic lipid tracers in surface soils from arid urban areas of Saudi Arabia

International Nuclear Information System (INIS)

Rushdi, Ahmed I.; Al-Mutlaq, Khalid F.; El-Mubarak, Aarif H.; Al-Saleh, Mohammed A.; El-Otaibi, Mubarak T.; Ibrahim, Sami M.M.; Simoneit, Bernd R.T.

2016-01-01

Soil particles contain a variety of natural and anthropogenic organic components, and in urban areas can be considered as local collectors of pollutants. Surface soil samples were taken from ten urban areas in Riyadh during early winter of 2007. They were extracted with dichloromethane-methanol mixture and the extracts were analyzed by gas chromatography-mass spectrometry. The major compounds were unresolved complex mixture (UCM), plasticizers, n-alkanes, carbohydrates, n-alkanoic acids, hopanes, n-alkanols, and sterols. Vegetation detritus was the major natural source of organic compounds (24.0 ± 15.7%) in samples from areas with less human activities and included n-alkanes, n-alkanoic acids, n-alkanols, sterols and carbohydrates. Vehicular emission products and discarded plastics were the major anthropogenic sources in the soil particles (53.3 ± 21.3% and 22.7 ± 10.7%, respectively). The anthropogenic tracers were UCM, plasticizers, n-alkanes, hopanes and traces of steranes. Vegetation and human activities control the occurrence and distribution of natural and anthropogenic extractable organic matter in this arid urban area. - Highlights: • Human activities influence the distribution of EOM in soils of urban arid regions. • Petroleum residues and plastics are the dominant anthropogenic input. • Low soil organic matter and moisture limit microbial/fungal alteration. - This work shows that human activities are critical factors that influence the characteristics and distribution of EOM in soils of arid urban regions.

Sources and trends of environmental mercury emissions in Asia.

Science.gov (United States)

Wong, Coby S C; Duzgoren-Aydin, Nurdan S; Aydin, Adnan; Wong, Ming H

2006-09-15

This paper focuses on environmental mercury emissions in Asia and elaborates its probable trend in the future and associated implications given the anticipated socioeconomic outlook and other macro-environmental factors. Among the various regions, Asia has become the largest contributor of anthropogenic atmospheric Hg, responsible for over half of the global emission. In the next few decades, a significant increase in anthropogenic Hg emissions in Asia is likely owing to rapid economic and industrial development, unless drastic measures are taken. In particular, the dominance of Asia in some Hg-emitting industries, such as coal combustion, steel production and gold mining, provokes a serious environmental concern over their potential contributions of incidental Hg in the region. Moreover, the increasing prevalence of electrical and electronic manufacturing industry as a user and a contributor of Hg in Asia is also worrying. Specifically, disposal of obsolete electrical and electronic wastes represents a phenomenon increasingly encountered in Asia. In addition to escalating anthropogenic Hg emissions in Asia, associated environmental and health implications may also exacerbate in the region for the probable effects of a unique combination of climatic (e.g. subtropical climate), environmental (e.g. acid rain) and socioeconomic factors (e.g. high population density). Hence, much effort is still needed to understand the role of Asia in global Hg cycle and associated environmental and health effects in the region.

Sources and trends of environmental mercury emissions in Asia

International Nuclear Information System (INIS)

Wong, Coby S.C.; Duzgoren-Aydin, Nurdan S.; Aydin, Adnan; Wong, Ming H.

2006-01-01

This paper focuses on environmental mercury emissions in Asia and elaborates its probable trend in the future and associated implications given the anticipated socioeconomic outlook and other macro-environmental factors. Among the various regions, Asia has become the largest contributor of anthropogenic atmospheric Hg, responsible for over half of the global emission. In the next few decades, a significant increase in anthropogenic Hg emissions in Asia is likely owing to rapid economic and industrial development, unless drastic measures are taken. In particular, the dominance of Asia in some Hg-emitting industries, such as coal combustion, steel production and gold mining, provokes a serious environmental concern over their potential contributions of incidental Hg in the region. Moreover, the increasing prevalence of electrical and electronic manufacturing industry as a user and a contributor of Hg in Asia is also worrying. Specifically, disposal of obsolete electrical and electronic wastes represents a phenomenon increasingly encountered in Asia. In addition to escalating anthropogenic Hg emissions in Asia, associated environmental and health implications may also exacerbate in the region for the probable effects of a unique combination of climatic (e.g. subtropical climate), environmental (e.g. acid rain) and socioeconomic factors (e.g. high population density). Hence, much effort is still needed to understand the role of Asia in global Hg cycle and associated environmental and health effects in the region

Environmental effects of increased atmospheric carbon dioxide

International Nuclear Information System (INIS)

Soon, W.; Baliunas, S.L.; Robinson, A.B.; Robinson, Z.W.

1999-01-01

A review of the literature concerning the environmental consequences of increased levels of atmospheric carbon dioxide leads to the conclusion that increases during the 20th century have produced no deleterious effects upon global climate or temperature. Increased carbon dioxide has, however, markedly increased plant growth rates as inferred from numerous laboratory and field experiments. There is no clear evidence, nor unique attribution, of the global effects of anthropogenic CO 2 on climate. Meaningful integrated assessments of the environmental impacts of anthropogenic CO 2 are not yet possible because model estimates of global and regional climate changes on interannual, decadal and centennial timescales remain highly uncertain.(author)

Future Climate Impacts of Direct Radiative Forcing Anthropogenic Aerosols, Tropospheric Ozone, and Long-lived Greenhouse Gases

Science.gov (United States)

Chen, Wei-Ting; Liao, Hong; Seinfeld, John H.

2007-01-01

Long-lived greenhouse gases (GHGs) are the most important driver of climate change over the next century. Aerosols and tropospheric ozone (O3) are expected to induce significant perturbations to the GHG-forced climate. To distinguish the equilibrium climate responses to changes in direct radiative forcing of anthropogenic aerosols, tropospheric ozone, and GHG between present day and year 2100, four 80-year equilibrium climates are simulated using a unified tropospheric chemistry-aerosol model within the Goddard Institute for Space Studies (GISS) general circulation model (GCM) 110. Concentrations of sulfate, nitrate, primary organic (POA) carbon, secondary organic (SOA) carbon, black carbon (BC) aerosols, and tropospheric ozone for present day and year 2100 are obtained a priori by coupled chemistry-aerosol GCM simulations, with emissions of aerosols, ozone, and precursors based on the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenario (SRES) A2. Changing anthropogenic aerosols, tropospheric ozone, and GHG from present day to year 2100 is predicted to perturb the global annual mean radiative forcing by +0.18 (considering aerosol direct effects only), +0.65, and +6.54 W m(sup -2) at the tropopause, and to induce an equilibrium global annual mean surface temperature change of +0.14, +0.32, and +5.31 K, respectively, with the largest temperature response occurring at northern high latitudes. Anthropogenic aerosols, through their direct effect, are predicted to alter the Hadley circulation owing to an increasing interhemispheric temperature gradient, leading to changes in tropical precipitation. When changes in both aerosols and tropospheric ozone are considered, the predicted patterns of change in global circulation and the hydrological cycle are similar to those induced by aerosols alone. GHG-induced climate changes, such as amplified warming over high latitudes, weakened Hadley circulation, and increasing precipitation over the

Morphological divergence and flow-induced phenotypic plasticity in a native fish from anthropogenically altered stream habitats.

Science.gov (United States)

Franssen, Nathan R; Stewart, Laura K; Schaefer, Jacob F

2013-11-01

Understanding population-level responses to human-induced changes to habitats can elucidate the evolutionary consequences of rapid habitat alteration. Reservoirs constructed on streams expose stream fishes to novel selective pressures in these habitats. Assessing the drivers of trait divergence facilitated by these habitats will help identify evolutionary and ecological consequences of reservoir habitats. We tested for morphological divergence in a stream fish that occupies both stream and reservoir habitats. To assess contributions of genetic-level differences and phenotypic plasticity induced by flow variation, we spawned and reared individuals from both habitats types in flow and no flow conditions. Body shape significantly and consistently diverged in reservoir habitats compared with streams; individuals from reservoirs were shallower bodied with smaller heads compared with individuals from streams. Significant population-level differences in morphology persisted in offspring but morphological variation compared with field-collected individuals was limited to the head region. Populations demonstrated dissimilar flow-induced phenotypic plasticity when reared under flow, but phenotypic plasticity in response to flow variation was an unlikely explanation for observed phenotypic divergence in the field. Our results, together with previous investigations, suggest the environmental conditions currently thought to drive morphological change in reservoirs (i.e., predation and flow regimes) may not be the sole drivers of phenotypic change.

Bacterial biodiversity-ecosystem functioning relations are modified by environmental complexity.

Science.gov (United States)

Langenheder, Silke; Bulling, Mark T; Solan, Martin; Prosser, James I

2010-05-26

With the recognition that environmental change resulting from anthropogenic activities is causing a global decline in biodiversity, much attention has been devoted to understanding how changes in biodiversity may alter levels of ecosystem functioning. Although environmental complexity has long been recognised as a major driving force in evolutionary processes, it has only recently been incorporated into biodiversity-ecosystem functioning investigations. Environmental complexity is expected to strengthen the positive effect of species richness on ecosystem functioning, mainly because it leads to stronger complementarity effects, such as resource partitioning and facilitative interactions among species when the number of available resource increases. Here we implemented an experiment to test the combined effect of species richness and environmental complexity, more specifically, resource richness on ecosystem functioning over time. We show, using all possible combinations of species within a bacterial community consisting of six species, and all possible combinations of three substrates, that diversity-functioning (metabolic activity) relationships change over time from linear to saturated. This was probably caused by a combination of limited complementarity effects and negative interactions among competing species as the experiment progressed. Even though species richness and resource richness both enhanced ecosystem functioning, they did so independently from each other. Instead there were complex interactions between particular species and substrate combinations. Our study shows clearly that both species richness and environmental complexity increase ecosystem functioning. The finding that there was no direct interaction between these two factors, but that instead rather complex interactions between combinations of certain species and resources underlie positive biodiversity ecosystem functioning relationships, suggests that detailed knowledge of how individual

Bacterial biodiversity-ecosystem functioning relations are modified by environmental complexity.

Directory of Open Access Journals (Sweden)

Silke Langenheder

Full Text Available BACKGROUND: With the recognition that environmental change resulting from anthropogenic activities is causing a global decline in biodiversity, much attention has been devoted to understanding how changes in biodiversity may alter levels of ecosystem functioning. Although environmental complexity has long been recognised as a major driving force in evolutionary processes, it has only recently been incorporated into biodiversity-ecosystem functioning investigations. Environmental complexity is expected to strengthen the positive effect of species richness on ecosystem functioning, mainly because it leads to stronger complementarity effects, such as resource partitioning and facilitative interactions among species when the number of available resource increases. METHODOLOGY/PRINCIPAL FINDINGS: Here we implemented an experiment to test the combined effect of species richness and environmental complexity, more specifically, resource richness on ecosystem functioning over time. We show, using all possible combinations of species within a bacterial community consisting of six species, and all possible combinations of three substrates, that diversity-functioning (metabolic activity relationships change over time from linear to saturated. This was probably caused by a combination of limited complementarity effects and negative interactions among competing species as the experiment progressed. Even though species richness and resource richness both enhanced ecosystem functioning, they did so independently from each other. Instead there were complex interactions between particular species and substrate combinations. CONCLUSIONS/SIGNIFICANCE: Our study shows clearly that both species richness and environmental complexity increase ecosystem functioning. The finding that there was no direct interaction between these two factors, but that instead rather complex interactions between combinations of certain species and resources underlie positive biodiversity

Reviews and syntheses: Anthropogenic perturbations to carbon fluxes in Asian river systems - concepts, emerging trends, and research challenges

Science.gov (United States)

Park, Ji-Hyung; Nayna, Omme K.; Begum, Most S.; Chea, Eliyan; Hartmann, Jens; Keil, Richard G.; Kumar, Sanjeev; Lu, Xixi; Ran, Lishan; Richey, Jeffrey E.; Sarma, Vedula V. S. S.; Tareq, Shafi M.; Xuan, Do Thi; Yu, Ruihong

2018-05-01

Human activities are drastically altering water and material flows in river systems across Asia. These anthropogenic perturbations have rarely been linked to the carbon (C) fluxes of Asian rivers that may account for up to 40-50 % of the global fluxes. This review aims to provide a conceptual framework for assessing the human impacts on Asian river C fluxes, along with an update on anthropogenic alterations of riverine C fluxes. Drawing on case studies conducted in three selected rivers (the Ganges, Mekong, and Yellow River) and other major Asian rivers, the review focuses on the impacts of river impoundment and pollution on CO2 outgassing from the rivers draining South, Southeast, and East Asian regions that account for the largest fraction of river discharge and C exports from Asia and Oceania. A critical examination of major conceptual models of riverine processes against observed trends suggests that to better understand altered metabolisms and C fluxes in anthropogenic land-water-scapes, or riverine landscapes modified by human activities, the traditional view of the river continuum should be complemented with concepts addressing spatial and temporal discontinuities created by human activities, such as river impoundment and pollution. Recent booms in dam construction on many large Asian rivers pose a host of environmental problems, including increased retention of sediment and associated C. A small number of studies that measured greenhouse gas (GHG) emissions in dammed Asian rivers have reported contrasting impoundment effects: decreased GHG emissions from eutrophic reservoirs with enhanced primary production vs. increased emissions from the flooded vegetation and soils in the early years following dam construction or from the impounded reaches and downstream estuaries during the monsoon period. These contrasting results suggest that the rates of metabolic processes in the impounded and downstream reaches can vary greatly longitudinally over time as a

Our fingerprint in tsunami deposits - anthropogenic markers as a new tsunami identification tool

Science.gov (United States)

Bellanova, P.; Schwarzbauer, J.; Reicherter, K. R.; Jaffe, B. E.; Szczucinski, W.

2016-12-01

Several recent geochemical studies have focused on the use of inorganic indicators to evaluate a tsunami origin of sediment in the geologic record. However, tsunami transport not only particulate sedimentary material from marine to terrestrial areas (and vice versa), but also associated organic material. Thus, tsunami deposits may be characterized by organic-geochemical parameters. Recently increased attention has been given to the use of natural organic substances (biomarkers) to identify tsunami deposits. To date no studies have been made investigating anthropogenic organic indicators in recent tsunami deposits. Anthropogenic organic markers are more sensitive and reliable markers compared to other tracers due to their specific molecular structural properties and higher source specificity. In this study we evaluate whether anthropogenic substances are useful indicators for determining whether an area has been inundated by a tsunami. We chose the Sendai Plain and Sanemoura and Oppa Bays, Japan, as study sites because the destruction of infrastructure by flooding released environmental pollutants (e.g., fuels, fats, tarmac, plastics, heavy metals, etc.) contaminating large areas of the coastal zone during the 2011 Tohoku-oki tsunami. Organic compounds from the tsunami deposits are extracted from tsunami sediment and compared with the organic signature of unaffected pre-tsunami samples using gas chromatography-mass spectrometry (GS/MS) based analyses. For the anthropogenic markers, compounds such as soil derived pesticides (DDT), source specific PAHs, halogenated aromatics from industrial sources were detected and used to observe the inland extent and the impact of the Tohoku-oki tsunami on the coastal region around Sendai.

Anthropogenic nitrogen deposition ameliorates the decline in tree growth caused by a drier climate.

Science.gov (United States)

Ibáñez, Inés; Zak, Donald R; Burton, Andrew J; Pregitzer, Kurt S

2018-02-01

Most forest ecosystems are simultaneously affected by concurrent global change drivers. However, when assessing these effects, studies have mainly focused on the responses to single factors and have rarely evaluated the joined effects of the multiple aspects of environmental change. Here, we analyzed the combined effects of anthropogenic nitrogen (N) deposition and climatic conditions on the radial growth of Acer saccharum, a dominant tree species in eastern North American forests. We capitalized on a long-term N deposition study, replicated along a latitudinal gradient, that has been taking place for more than 20 yr. We analyzed tree radial growth as a function of anthropogenic N deposition (ambient and experimental addition) and of summer temperature and soil water conditions. Our results reveal that experimental N deposition enhances radial growth of this species, an effect that was accentuated as temperature increased and soil water became more limiting. The spatial and temporal extent of our data also allowed us to assert that the positive effects of growing under the experimental N deposition are likely due to changes in the physiological performance of this species, and not due to the positive correlation between soil N and soil water holding capacity, as has been previously speculated in other studies. Our simulations of tree growth under forecasted climate scenarios specific for this region also revealed that although anthropogenic N deposition may enhance tree growth under a large array of environmental conditions, it will not mitigate the expected effects of growing under the considerably drier conditions characteristic of our most extreme climatic scenario. © 2018 by the Ecological Society of America.

Functional changes in littoral macroinvertebrate communities in response to watershed-level anthropogenic stress.

Directory of Open Access Journals (Sweden)

Katya E Kovalenko

Full Text Available Watershed-scale anthropogenic stressors have profound effects on aquatic communities. Although several functional traits of stream macroinvertebrates change predictably in response to land development and urbanization, little is known about macroinvertebrate functional responses in lakes. We assessed functional community structure, functional diversity (Rao's quadratic entropy and voltinism in macroinvertebrate communities sampled across the full gradient of anthropogenic stress in Laurentian Great Lakes coastal wetlands. Functional diversity and voltinism significantly decreased with increasing development, whereas agriculture had smaller or non-significant effects. Functional community structure was affected by watershed-scale development, as demonstrated by an ordination analysis followed by regression. Because functional community structure affects energy flow and ecosystem function, and functional diversity is known to have important implications for ecosystem resilience to further environmental change, these results highlight the necessity of finding ways to remediate or at least ameliorate these effects.

Temporal and spatial patterns of anthropogenic disturbance at McMurdo Station, Antarctica

International Nuclear Information System (INIS)

Kennicutt, Mahlon C II; Klein, Andrew; Montagna, Paul; Palmer, Terence; Sweet, Stephen; Wade, Terry; Sericano, Jose; Denoux, Guy

2010-01-01

Human visitations to Antarctica have increased in recent decades, raising concerns about preserving the continent's environmental quality. To understand the spatial and temporal patterns of anthropogenic disturbances at the largest scientific station in Antarctica, McMurdo Station, a long-term monitoring program has been implemented. Results from the first nine years (1999-2007) of monitoring are reported. Most physical disturbance of land surfaces occurred prior to 1970 during initial establishment of the station. Hydrocarbons from fuel and anthropogenic metals occur in patches of tens to hundreds of square meters in areas of fuel usage and storage. Most soil contaminant concentrations are not expected to elicit biological responses. Past disposal practices have contaminated marine sediments with polychlorinated biphenyls (PCBs), petroleum hydrocarbons, and metals in close proximity to the station that often exceed concentrations expected to elicit biological responses. Chemical contamination and organic enrichment reduced marine benthic ecological integrity within a few hundred meters offshore of the station. Contaminants were detected in marine benthic organisms confirming bioavailability and uptake. PCBs in sediments are similar to suspected source materials, indicating minimal microbial degradation decades after release. Anthropogenic disturbance of the marine environment is likely to persist for decades. A number of monitoring design elements, indicators and methodologies used in temperate climates were effective and provide guidance for monitoring programs elsewhere in Antarctica.

Environmental Sustainability of the Lopota River in Eastern Georgia against the Background of the Growing Anthropogenic Load

Directory of Open Access Journals (Sweden)

Tea T. Mchedluri

2014-03-01

Full Text Available We studied the ecological state of the Lopota River in Eastern Georgia. The study showed that the results of microbiological and chemical contamination do not experience significant changes, and mainly are within the acceptable range of concentration, although a pronounced difference is observed among individual performances over the entire flow. An increase in the anthropogenic pollution of the river is observed in summer time. Downstream the Alazani River the concentration of major cations ((K+,Na+,Mg2+,Ca2+, anions (SO42-, Cl- HCO3-, CO32- and biogenic elements (NO2, NO3-, NH4+, PO43- is increasing. As a result, the Lopota River is subjected to anthropogenic influence and faecal contamination. However, despite this, the ecological state of the river is satisfactory, due the turbulent flow of the river and good aeration. In addition, the increase in turbidity creates favourable conditions for sorption water purification. All this contributes to self-purification capacity of the river.

Microbiota and environmental stress: how pollution affects microbial communities in Manila clams.

Science.gov (United States)

Milan, M; Carraro, L; Fariselli, P; Martino, M E; Cavalieri, D; Vitali, F; Boffo, L; Patarnello, T; Bargelloni, L; Cardazzo, B

2018-01-01

Given the crucial role of microbiota in host development, health, and environmental interactions, genomic analyses focusing on host-microbiota interactions should certainly be considered in the investigation of the adaptive mechanisms to environmental stress. Recently, several studies suggested that microbiota associated to digestive tract is a key, although still not fully understood, player that must be considered to assess the toxicity of environmental contaminants. Bacteria-dependent metabolism of xenobiotics may indeed modulate the host toxicity. Conversely, environmental variables (including pollution) may alter the microbial community and/or its metabolic activity leading to host physiological alterations that may contribute to their toxicity. Here, 16s rRNA gene amplicon sequencing has been applied to characterize the hepatopancreas microbiota composition of the Manila clam, Ruditapes philippinarum. The animals were collected in the Venice lagoon area, which is subject to different anthropogenic pressures, mainly represented by the industrial activities of Porto Marghera (PM). Seasonal and geographic differences in clam microbiotas were explored and linked to host response to chemical stress identified in a previous study at the transcriptome level, establishing potential interactions among hosts, microbes, and environmental parameters. The obtained results showed the recurrent presence of putatively detoxifying bacterial taxa in PM clams during winter and over-representation of several metabolic pathways involved in xenobiotic degradation, which suggested the potential for host-microbial synergistic detoxifying actions. Strong interaction between seasonal and chemically-induced responses was also observed, which partially obscured such potentially synergistic actions. Seasonal variables and exposure to toxicants were therefore shown to interact and substantially affect clam microbiota, which appeared to mirror host response to environmental variation. It

Anthropogenic Biomes of the World, Version 2: 1700

Data.gov (United States)

National Aeronautics and Space Administration — The Anthropogenic Biomes of the World, Version 2: 1700 data set describes anthropogenic transformations within the terrestrial biosphere caused by sustained direct...

Anthropogenic Biomes of the World, Version 2: 1900

Data.gov (United States)

National Aeronautics and Space Administration — The Anthropogenic Biomes of the World, Version 2: 1900 data set describes anthropogenic transformations within the terrestrial biosphere caused by sustained direct...

Anthropogenic Biomes of the World, Version 2: 1800

Data.gov (United States)

National Aeronautics and Space Administration — The Anthropogenic Biomes of the World, Version 2: 1800 data set describes anthropogenic transformations within the terrestrial biosphere caused by sustained direct...

Anthropogenic Biomes of the World, Version 2: 2000

Data.gov (United States)

National Aeronautics and Space Administration — The Anthropogenic Biomes of the World, Version 2: 2000 data set describes anthropogenic transformations within the terrestrial biosphere caused by sustained direct...

Natural and anthropogenic mercury sources and their impact on the air-surface exchange of mercury on regional and global scales

Energy Technology Data Exchange (ETDEWEB)

Ebinghaus, R.; Tripathi, R.M.; Wallschlaeger, D.; Lindberg, S.E.

1998-12-31

Mercury is outstanding among the global environmental pollutants of continuing concern. Especially in the last decade of the 20th century, environmental scientists, legislators, politicians and the public have become aware of mercury pollution in the global environment. It has often been suggested that anthropogenic emissions are leading to a general increase in mercury on local, regional, and global scales (Lindqvist et al. 1991; Expert Panel 1994). Mercury is emitted into the atmosphere from a number of natural as well as anthropogenic sources. In contrast with most of the other heavy metals, mercury and many of its compounds behave exceptionally in the environment due to their volatility and capability for methylation. Long-range atmospheric transport of mercury, its transformation to more toxic methylmercury compounds, and their bioaccumulation in the aquatic foodchain have motivated intensive research on mercury as a pollutant of global concern. Mercury takes part in a number of complex environmental cycles, and special interest is focused on the aquatic-biological and the atmospheric cycles. (orig./SR)

Natural and anthropogenic mercury sources and their impact on the air-surface exchange of mercury on regional and global scales

Energy Technology Data Exchange (ETDEWEB)

Ebinghaus, R; Tripathi, R M; Wallschlaeger, D; Lindberg, S E

1999-12-31

Mercury is outstanding among the global environmental pollutants of continuing concern. Especially in the last decade of the 20th century, environmental scientists, legislators, politicians and the public have become aware of mercury pollution in the global environment. It has often been suggested that anthropogenic emissions are leading to a general increase in mercury on local, regional, and global scales (Lindqvist et al. 1991; Expert Panel 1994). Mercury is emitted into the atmosphere from a number of natural as well as anthropogenic sources. In contrast with most of the other heavy metals, mercury and many of its compounds behave exceptionally in the environment due to their volatility and capability for methylation. Long-range atmospheric transport of mercury, its transformation to more toxic methylmercury compounds, and their bioaccumulation in the aquatic foodchain have motivated intensive research on mercury as a pollutant of global concern. Mercury takes part in a number of complex environmental cycles, and special interest is focused on the aquatic-biological and the atmospheric cycles. (orig./SR)

Seasonal variations in the sources of natural and anthropogenic lead deposited at the East Rongbuk Glacier in the high-altitude Himalayas.

Science.gov (United States)

Burn-Nunes, Laurie; Vallelonga, Paul; Lee, Khanghyun; Hong, Sungmin; Burton, Graeme; Hou, Shugui; Moy, Andrew; Edwards, Ross; Loss, Robert; Rosman, Kevin

2014-07-15

Lead (Pb) isotopic compositions and concentrations, and barium (Ba) and indium (In) concentrations have been analysed at sub-annual resolution in three sections from a snow pit samples dated to 2004/2005, recovered from the East Rongbuk Glacier in the high-altitude Himalayas. Ice core sections indicate that atmospheric chemistry prior to ~1,953 was controlled by mineral dust inputs, with no discernible volcanic or anthropogenic contributions. Eighteenth century monsoon ice core chemistry is indicative of dominant contributions from local Himalayan sources; non-monsoon ice core chemistry is linked to contributions from local (Himalayan), regional (Indian/Thar Desert) and long-range (North Africa, Central Asia) sources. Twentieth century monsoon and non-monsoon ice core data demonstrate similar seasonal sources of mineral dust, however with a transition to less-radiogenic isotopic signatures that suggests local and regional climate/environmental change. The snow pit record demonstrates natural and anthropogenic contributions during both seasons, with increased anthropogenic influence during non-monsoon times. Monsoon anthropogenic inputs are most likely sourced to South/South-East Asia and/or India, whereas non-monsoon anthropogenic inputs are most likely sourced to India and Central Asia. Copyright © 2014 Elsevier B.V. All rights reserved.

Paleolimnological investigations of anthropogenic environmental change in Lake Tanganyika: I. An introduction to the project

Science.gov (United States)

Cohen, A.S.; Palacios-Fest, M. R.; McGill, J.; Swarzenski, P.W.; Verschuren, D.; Sinyinza, R.; Songori, T.; Kakagozo, B.; Syampila, M.; O'Reilly, C. M.; Alin, S.R.

2005-01-01

We investigated paleolimnological records from a series of river deltas around the northeastern rim of Lake Tanganyika, East Africa (Tanzania and Burundi) in order to understand the history of anthropogenic activity in the lake's catchment over the last several centuries, and to determine the impact of these activities on the biodiversity of littoral and sublittoral lake communities. Sediment pollution caused by increased rates of soil erosion in deforested watersheds has caused significant changes in aquatic communities along much of the lake's shoreline. We analyzed the effects of sediment discharge on biodiversity around six deltas or delta complexes on the east coast of Lake Tanganyika: the Lubulungu River delta, Kabesi River delta, Nyasanga/Kahama River deltas, and Mwamgongo River delta in Tanzania; and the Nyamuseni River delta and Karonge/Kirasa River deltas in Burundi. Collectively, these deltas and their associated rivers were chosen to represent a spectrum of drainage-basin sizes and disturbance levels. By comparing deltas that are similar in watershed attributes (other than disturbance levels), our goal was to explore a series of historical "experiments" at the watershed scale, with which we could more clearly evaluate hypotheses of land use or other effects on nearshore ecosystems. Here we discuss these deltas, their geologic and physiographic characteristics, and the field procedures used for coring and sampling the deltas, and various indicators of anthropogenic impact. ?? Springer 2005.

Assessing flow regime alterations in a temporary river – the River Celone case study

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De Girolamo Anna Maria

2015-09-01

Full Text Available In this paper, we present an approach to evaluate the hydrological alterations of a temporary river. In these rivers, it is expected that anthropogenic pressures largely modify low-flow components of the flow regime with consequences for aquatic habitat and diversity in invertebrate species. First, by using a simple hydrological index (IARI river segments of the Celone stream (southern Italy whose hydrological regime is significantly influenced by anthropogenic activities have been identified. Hydrological alteration has been further classified through the analysis of two metrics: the degree (Mf and the predictability of dry flow conditions (Sd6. Measured streamflow data were used to calculate the metrics in present conditions (impacted. Given the lack of data from pristine conditions, simulated streamflow time series were used to calculate the metrics in reference conditions. The Soil and Water Assessment Tool (SWAT model was used to estimate daily natural streamflow. Hydrological alterations associated with water abstractions, point discharges and the presence of a reservoir were assessed by comparing the metrics (Mf, Sd6 before and after the impacts. The results show that the hydrological regime of the river segment located in the upper part of the basin is slightly altered, while the regime of the river segment downstream of the reservoir is heavily altered. This approach is intended for use with ecological metrics in defining the water quality status and in planning streamflow management activities.

Environmental alterations in biofuel generating molecules in Zilla spinosa.

Science.gov (United States)

Khattab, Hemmat; El Marid, Zeinab

2017-03-01

Now days, production of fuels and petrochemicals from renewable lignocellulosic biomass is an indispensable issue to meet the growing energy demand. Meanwhile, the changes in the climate and soil topography influence the growth and development as well as canopy level of the lignocellulosic biomass. In this study, Zilla spinosa Turr (Zilla) plants with similar age and size were collected from three main sectors (upstream, midstream, and downstream) of Wadi Hagul during spring (April) and summer (July) seasons. Environmental stresses evoked reduction in the energy trapping pigments concomitant with increments in chlorophyll fluorescence in summer harvested plants particularly at downstream. Furthermore, the biofuels generating compounds including carbohydrate, lignin, and lipid making the plant biomasses are greatly affected by environmental conditions. Greater amount of lignin was estimated in summer harvested Z. spinosa shoots particularly at downstream. Moreover, the total oil content which is a promising source of biodiesel was considerably decreased during summer season particularly at downstream. The physical properties of the lipids major constituent fatty acid methyl esters determine the biofuel properties and contribute in the adaptation of plants against environmental stresses. Hence, the analysis of fatty acid profile showed significant modifications under combined drought and heat stress displayed in the summer season. The maximum increase in saturated fatty acid levels including tridecanoic acid (C13:0), pentadeanoic acid (C15:0), palmitic acid (C16:0), and stearic acid (C18:0) were estimated in spring harvested Z. spinosa aerial portions particularly at midstream. In spite of the reduction in the total oil content, a marked increase in the value of unsaturated to saturated fatty acids ratio and thereby the unsaturation index were achieved during the dry summer period. Henceforth, these seasonal and spatial variations in fatty acids profiles may

Anthropogenic effect on avalanche and debris flow activity

OpenAIRE

S. A. Sokratov; Yu. G. Seliverstov; A. L. Shnyparkov; K. P. Koltermann

2013-01-01

The paper presents examples of the change in snow avalanches and debris flows activity due to the anthropogenic pressure on vegetation and relief. The changes in dynamical characteristics of selected snow avalanches and debris flows due to the anthropogenic activity are quantified. The conclusion is made that the anthropogenic effects on the snow avalanches and debris flows activity are more pronounced than the possible effects of the climate change. The necessity is expressed on the unavoida...

Human-induced geomorphic change across environmental gradients

Science.gov (United States)

Vanacker, V.; Molina, A.; Bellin, N.; Christl, M.

2016-12-01

Human-induced land cover changes are causing important adverse effects on the ecological services rendered by mountain ecosystems, and the number of case-studies of the impact of humans on soil erosion and sediment yield has mounted rapidly. Anthropogenic disturbance of natural vegetation can profoundly alter the physical, chemical and biological processes within soils. Rapid removal of topsoil during intense farming can result in an imbalance between soil production through chemical weathering and physical soil erosion, with direct implications on nutrient cycling, soil fertility and agricultural production. In this study, we present a conceptual model for assessing human-induced erosion for a wide variety of environmental settings and pose that human-induced geomorphic change cannot be assessed solely based on modern erosion rates as natural or baseline erosion rates can be important in e.g. mountainous terrain. As such, we assess the vulnerability of a given ecosystem to human-induced land cover change by quantifying the change in catchment-wide erosion rates resulting from anthropogenic changes in vegetation cover. Human-induced erosion is here approximated by the ratio of the total specific sediment yield to the natural erosional mass flux, and is dimensionless. The conceptual model is applied to three contrasting environmental settings where data on soil production, physical soil erosion and long-term denudation are available: the tropical Andes, subtropical southern Brazil, and semi-arid Spanish Cordillera. The magnitude of human-induced geomorphic change strongly differs between the three regions. The data suggest that the sensitivity to human-induced erosion is ecosystem dependent, and related to soil erosivity and potential vegetation cover disturbances as a result of human impact. It may therefore be expected that the potential for erosion regulation is larger in well-vegetated ecosystem where strong differences may exist in vegetation cover between

Reviews and syntheses: Anthropogenic perturbations to carbon fluxes in Asian river systems – concepts, emerging trends, and research challenges

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J.-H. Park

2018-05-01

Full Text Available Human activities are drastically altering water and material flows in river systems across Asia. These anthropogenic perturbations have rarely been linked to the carbon (C fluxes of Asian rivers that may account for up to 40–50 % of the global fluxes. This review aims to provide a conceptual framework for assessing the human impacts on Asian river C fluxes, along with an update on anthropogenic alterations of riverine C fluxes. Drawing on case studies conducted in three selected rivers (the Ganges, Mekong, and Yellow River and other major Asian rivers, the review focuses on the impacts of river impoundment and pollution on CO2 outgassing from the rivers draining South, Southeast, and East Asian regions that account for the largest fraction of river discharge and C exports from Asia and Oceania. A critical examination of major conceptual models of riverine processes against observed trends suggests that to better understand altered metabolisms and C fluxes in anthropogenic land-water-scapes, or riverine landscapes modified by human activities, the traditional view of the river continuum should be complemented with concepts addressing spatial and temporal discontinuities created by human activities, such as river impoundment and pollution. Recent booms in dam construction on many large Asian rivers pose a host of environmental problems, including increased retention of sediment and associated C. A small number of studies that measured greenhouse gas (GHG emissions in dammed Asian rivers have reported contrasting impoundment effects: decreased GHG emissions from eutrophic reservoirs with enhanced primary production vs. increased emissions from the flooded vegetation and soils in the early years following dam construction or from the impounded reaches and downstream estuaries during the monsoon period. These contrasting results suggest that the rates of metabolic processes in the impounded and downstream reaches can vary greatly longitudinally

Anthropogenic influence on forest landscape in the Khumbu valley, Nepal

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Lingua, Emanuele; Garbarino, Matteo; Urbinati, Carlo; Carrer, Marco

2013-04-01

High altitude Himalayan regions are geo-dynamically very active and very sensitive to natural and anthropogenic disturbances due to their steep slopes, variations of precipitations with elevation and short growing periods. Nonetheless, even in this remote region human pressure is often the most important factor affecting forest landscape. In the last decades the firewood demand has increased each year between September to December. The increase in the number of tourists, mountaineering, guides, porters, carpenters, lodges lead to a peak in the use of fuelwood. In order to understand anthropogenic impacts on forest, resources landscape and stand scale dynamics were analyzed in the Sagarmatha National Park (SNP) and its Buffer Zone in the Khumbu Valley (Nepal, Eastern Himalaya). Biological and historical data sources were employed, and a multi-scale approach was adopted to capture the influence of human activities on the distribution of tree species and forest structure. Stand structure and a range of environmental variables were sampled in 197 20x20 m square plots, and land use and anthropogenic variables were derived in a GIS environment (thematic maps and IKONOS, Landsat and Terra ASTER satellite images). We used multivariate statistical analyses to relate forest structure, anthropogenic influences, land uses, and topography. Fuel wood is the prime source of energy for cooking (1480-1880 Kg/person/year) and Quercus semecarpifolia, Rhododendron arboreum and Pinus wallichiana, among the others, are the most exploited species. Due to lack of sufficient energy sources deforestation is becoming a problem in the area. This might be a major threat causing soil erosion, landslides and other natural hazards. Among the 25 species of trees that were found in the Buffer Zone Community Forests of SNP, Pinus wallichiana, Lyonia ovalifolia, Quercus semecarpifolia and Rhododendron arboreum are the dominant species. The total stand density ranged from 228 to 379 tree/ha and the

Landscape alteration and habitat modification: impacts on plant-pollinator systems

OpenAIRE

Vanbergen, Adam J.

2014-01-01

Insect pollinators provide an important ecosystem service to many crop species and underpin the reproductive assurance of many wild plant species. Multiple, anthropogenic pressures threaten insect pollinators. Land-use change and intensification alters the habitats and landscapes that provide food and nesting resources for pollinators. These impacts vary according to species traits, producing winners and losers, while the intrinsic robustness of plant-pollinator networks may provide stability...

Distribution of biologic, anthropogenic, and volcanic constituents as a proxy for sediment transport in the San Francisco Bay Coastal System

Science.gov (United States)

McGann, Mary; Erikson, Li H.; Wan, Elmira; Powell, Charles; Maddocks, Rosalie F.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

2013-01-01

Although conventional sediment parameters (mean grain size, sorting, and skewness) and provenance have typically been used to infer sediment transport pathways, most freshwater, brackish, and marine environments are also characterized by abundant sediment constituents of biological, and possibly anthropogenic and volcanic, origin that can provide additional insight into local sedimentary processes. The biota will be spatially distributed according to its response to environmental parameters such as water temperature, salinity, dissolved oxygen, organic carbon content, grain size, and intensity of currents and tidal flow, whereas the presence of anthropogenic and volcanic constituents will reflect proximity to source areas and whether they are fluvially- or aerially-transported. Because each of these constituents have a unique environmental signature, they are a more precise proxy for that source area than the conventional sedimentary process indicators. This San Francisco Bay Coastal System study demonstrates that by applying a multi-proxy approach, the primary sites of sediment transport can be identified. Many of these sites are far from where the constituents originated, showing that sediment transport is widespread in the region. Although not often used, identifying and interpreting the distribution of naturally-occurring and allochthonous biologic, anthropogenic, and volcanic sediment constituents is a powerful tool to aid in the investigation of sediment transport pathways in other coastal systems.

Integrated approach to assessing streamflow and precipitation alterations under environmental change: Application in the Niger River Basin

Directory of Open Access Journals (Sweden)

Dagbegnon Clement Sohoulande Djebou

2015-09-01

New hydrological insights for the region: Over the period 1961–2012, I conduct a change point analysis of the streamflow and report two sub-periods 1961–1982 and 1983–2012. A comparison of precipitation and streamflow during these two time-slices shows meaningful changes. I describe a Kernel density analysis of streamflow and yield a probabilistic estimate of discharge anomalies along the river. Later, I evaluate seasonal trends of precipitation and streamflow. The analyses bring out critical alterations in time and space. However, these alterations seem to foreshadow critical environmental degradations occurring across the watershed. I consider LAI series derived from MODIS images, then I examine and discuss trends in land-cover dynamics in relation with the patterns in precipitation and streamflow. This late analytical step yields a holistic picture of the ongoing alterations in the Niger River Basin. Finally, I emphasize suggestions, valuable for a comprehensive water resources and environment management.

Effects of anthropogenic sound on digging behavior, metabolism, Ca2+/Mg2+ ATPase activity, and metabolism-related gene expression of the bivalve Sinonovacula constricta

Science.gov (United States)

Peng, Chao; Zhao, Xinguo; Liu, Saixi; Shi, Wei; Han, Yu; Guo, Cheng; Jiang, Jingang; Wan, Haibo; Shen, Tiedong; Liu, Guangxu

2016-01-01

Anthropogenic sound has increased significantly in the past decade. However, only a few studies to date have investigated its effects on marine bivalves, with little known about the underlying physiological and molecular mechanisms. In the present study, the effects of different types, frequencies, and intensities of anthropogenic sounds on the digging behavior of razor clams (Sinonovacula constricta) were investigated. The results showed that variations in sound intensity induced deeper digging. Furthermore, anthropogenic sound exposure led to an alteration in the O:N ratios and the expression of ten metabolism-related genes from the glycolysis, fatty acid biosynthesis, tryptophan metabolism, and Tricarboxylic Acid Cycle (TCA cycle) pathways. Expression of all genes under investigation was induced upon exposure to anthropogenic sound at ~80 dB re 1 μPa and repressed at ~100 dB re 1 μPa sound. In addition, the activity of Ca2+/Mg2+-ATPase in the feet tissues, which is directly related to muscular contraction and subsequently to digging behavior, was also found to be affected by anthropogenic sound intensity. The findings suggest that sound may be perceived by bivalves as changes in the water particle motion and lead to the subsequent reactions detected in razor clams. PMID:27063002

Effects of anthropogenic sound on digging behavior, metabolism, Ca(2+)/Mg(2+) ATPase activity, and metabolism-related gene expression of the bivalve Sinonovacula constricta.

Science.gov (United States)

Peng, Chao; Zhao, Xinguo; Liu, Saixi; Shi, Wei; Han, Yu; Guo, Cheng; Jiang, Jingang; Wan, Haibo; Shen, Tiedong; Liu, Guangxu

2016-04-11

Anthropogenic sound has increased significantly in the past decade. However, only a few studies to date have investigated its effects on marine bivalves, with little known about the underlying physiological and molecular mechanisms. In the present study, the effects of different types, frequencies, and intensities of anthropogenic sounds on the digging behavior of razor clams (Sinonovacula constricta) were investigated. The results showed that variations in sound intensity induced deeper digging. Furthermore, anthropogenic sound exposure led to an alteration in the O:N ratios and the expression of ten metabolism-related genes from the glycolysis, fatty acid biosynthesis, tryptophan metabolism, and Tricarboxylic Acid Cycle (TCA cycle) pathways. Expression of all genes under investigation was induced upon exposure to anthropogenic sound at ~80 dB re 1 μPa and repressed at ~100 dB re 1 μPa sound. In addition, the activity of Ca(2+)/Mg(2+)-ATPase in the feet tissues, which is directly related to muscular contraction and subsequently to digging behavior, was also found to be affected by anthropogenic sound intensity. The findings suggest that sound may be perceived by bivalves as changes in the water particle motion and lead to the subsequent reactions detected in razor clams.

Effects of anthropogenic sound on digging behavior, metabolism, Ca2+/Mg2+ ATPase activity, and metabolism-related gene expression of the bivalve Sinonovacula constricta

Science.gov (United States)

Peng, Chao; Zhao, Xinguo; Liu, Saixi; Shi, Wei; Han, Yu; Guo, Cheng; Jiang, Jingang; Wan, Haibo; Shen, Tiedong; Liu, Guangxu

2016-04-01

Anthropogenic sound has increased significantly in the past decade. However, only a few studies to date have investigated its effects on marine bivalves, with little known about the underlying physiological and molecular mechanisms. In the present study, the effects of different types, frequencies, and intensities of anthropogenic sounds on the digging behavior of razor clams (Sinonovacula constricta) were investigated. The results showed that variations in sound intensity induced deeper digging. Furthermore, anthropogenic sound exposure led to an alteration in the O:N ratios and the expression of ten metabolism-related genes from the glycolysis, fatty acid biosynthesis, tryptophan metabolism, and Tricarboxylic Acid Cycle (TCA cycle) pathways. Expression of all genes under investigation was induced upon exposure to anthropogenic sound at ~80 dB re 1 μPa and repressed at ~100 dB re 1 μPa sound. In addition, the activity of Ca2+/Mg2+-ATPase in the feet tissues, which is directly related to muscular contraction and subsequently to digging behavior, was also found to be affected by anthropogenic sound intensity. The findings suggest that sound may be perceived by bivalves as changes in the water particle motion and lead to the subsequent reactions detected in razor clams.

Data used in Xu et al., 2016 paper entitled "Characteristics and distributions of atmospheric mercury emitted from anthropogenic sources in Guiyang, southwestern China

Data.gov (United States)

U.S. Environmental Protection Agency — Mercury emissions data from anthropogenic sources as described in Xu et al., 2016. This dataset is associated with the following publication: Xu, X., N. Liu, M....

Anthropogenic activities impact on atmospheric environmental quality in a gas-flaring community: application of fuzzy logic modelling concept.

Science.gov (United States)

Akintola, Olayiwola Akin; Sangodoyin, Abimbola Yisau; Agunbiade, Foluso Oyedotun

2018-05-24

We present a modelling concept for evaluating the impacts of anthropogenic activities suspected to be from gas flaring on the quality of the atmosphere using domestic roof-harvested rainwater (DRHRW) as indicator. We analysed seven metals (Cu, Cd, Pb, Zn, Fe, Ca, and Mg) and six water quality parameters (acidity, PO 4 3- , SO 4 2- , NO 3 - , Cl - , and pH). These were used as input parameters in 12 sampling points from gas-flaring environments (Port Harcourt, Nigeria) using Ibadan as reference. We formulated the results of these input parameters into membership function fuzzy matrices based on four degrees of impact: extremely high, high, medium, and low, using regulatory limits as criteria. We generated indices that classified the degree of anthropogenic activity impact on the sites from the product membership function matrices and weight matrices, with investigated (gas-flaring) environment as between medium and high impact compared to those from reference (residential) environment that was classified as between low and medium impact. Major contaminants of concern found in the harvested rainwater were Pb and Cd. There is also the urgent need to stop gas-flaring activities in Port Harcourt area in particular and Niger Delta region of Nigeria in general, so as to minimise the untold health hazard that people living in the area are currently faced with. The fuzzy methodology presented has also indicated that the water cannot safely support potable uses and should not be consumed without purification due to the impact of anthropogenic activities in the area but may be useful for other domestic purposes.

Exploring environmental causes of altered ras effects: fragmentation plus integration?

Science.gov (United States)

Porta, Miquel; Ayude, Daniel; Alguacil, Juan; Jariod, Manuel

2003-02-01

Mutations in ras genes are the most common abnormality of oncogenes in human cancer and a major example of activation by point mutation. Experimental and epidemiological studies support the notion that Ki-ras activation and expression may be chemically related. We discuss the potential role of several environmental compounds in the induction or promotion of ras mutations in humans, with a focus on exocrine pancreatic cancer, the human tumor with the highest prevalence at diagnosis of Ki-ras mutations. Organochlorine compounds, organic solvents, and coffee compounds may play an indirect role in causing Ki-ras mutations, rather than as direct inducers of the mutations. Although for some organochlorine compounds the induction of point mutations in ras oncogenes cannot be excluded, it seems more likely that the effects of these compounds are mediated through nongenomic or indirectly genotoxic mechanisms of action. Organic solvents also may act via enzymatic induction of ras mutagens or by providing a proliferation advantage to ras-mutated cell clones. In exocrine pancreatic cancer, caffeine, other coffee compounds, or other factors with which coffee drinking is associated could modulate Ki-ras activation by interfering with DNA repair, cell-cycle checkpoints, and apoptosis. Asbestos, cigarette smoking, and some dietary factors also may be involved in the initiation or the promotion of Ki-ras mutations in lung and colon cancers. Further development of the mechanistic scenarios proposed here could contribute to a meaningful integration of biological, clinical, and environmental knowledge on the causes of altered ras effects. Copyright 2003 Wiley-Liss, Inc.

Natural and anthropogenic hydrocarbon inputs to sediments of Patos Lagoon Estuary, Brazil.

Science.gov (United States)

Medeiros, Patricia Matheus; Bícego, Márcia Caruso; Castelao, Renato Menezes; Del Rosso, Clarissa; Fillmann, Gilberto; Zamboni, Ademilson Josemar

2005-01-01

The Patos Lagoon Estuary, southern Brazil, is an area of environmental interest not only because of tourism, but also because of the presence of the second major port of Brazil, with the related industrial and shipping activities. Thus, potential hydrocarbon pollution was examined in this study. Sediment samples were collected at 10 sites in the estuary, extracted, and analyzed by GC-FID and GC-MS for composition and concentration of the following organic geochemical markers: normal and isoprenoid alkanes, petroleum biomarkers, linear alkylbenzenes (LABs), and polycyclic aromatic hydrocarbons (PAHs). The total concentrations varied from 1.1 to 129.6 microg g(-1) for aliphatic hydrocarbons, from 17.8 to 4510.6 ng g(-1) for petroleum biomarkers, from 3.2 to 1601.9 ng g(-1) for LABs, and from 37.7 to 11,779.9 ng g(-1) for PAHs. Natural hydrocarbons were mainly derived from planktonic inputs due to a usual development of blooms in the estuary. Terrestrial plant wax compounds prevailed at sites located far from Rio Grande City and subject to stronger currents. Anthropogenic hydrocarbons are related to combustion/pyrolysis processes of fossil fuel, release of unburned oil products and domestic/industrial waste outfalls. Anthropogenic hydrocarbon inputs were more apparent at sites associated with industrial discharges (petroleum distributor and refinery), shipping activities (dry docking), and sewage outfalls (sewage). The overall concentrations of anthropogenic hydrocarbons revealed moderate to high hydrocarbon pollution in the study area.

Anthropogenic infrastructure as a component of urbogeosystems

Directory of Open Access Journals (Sweden)

Oleksii Chuiev

2017-11-01

Full Text Available This article deals with the definition of the concept of "anthropogenic infrastructure" and attempts to find its place in the structure of urbogeosystems. The concept itself can not be called new, as many foreign authors have already used it, but the final definition never happened. The reasons why city studies are becoming more relevant in the face of ever-accelerating urbanization are briefly presented. Prerequisites for the emergence of the urban environment and approaches to its study are given. A special attention is paid to the consideration of urbosystems and their component structure. The main four components are described, which include the technosphere, biosphere, population and abiotic nature. The causes of the appearance of urban ecosystems and their specific features are analyzed. Based on the deficiencies of the "Urbosphere", "Urbosystem" and "Urboecosystem", the notion of "Urbogeosystem" is formed once again. Since architectural and construction objects are key components of such systems, their integration into anthropogenic infrastructure allows us to operate with a more general concept. Functional zones of the city, which are part of the anthropogenic infrastructure, are described. These include residential, industrial, forest and park areas. Examples of the use and functioning of each of the zones are given. An attempt has been made to estimate the boundaries of urbogeosystems. The existing approaches to the classification of anthropogenic infrastructure are analyzed. For one of them, it is advisable to allocate separately "hard" and "soft" infrastructure by the nature of the tasks of society, which they are called upon to satisfy. An alternative approach is to divide the anthropogenic infrastructure into "human" and "physical" ones. If the first satisfies the socio-cultural needs of people, the second is used for production, development, establishment of communications, transportation. It is proved why it is expedient to

Exploring Multiple Constraints of Anthropogenic Pollution

Science.gov (United States)

Arellano, A. F., Jr.; Tang, W.; Silva, S. J.; Raman, A.

2017-12-01

It is imperative that we provide more accurate and consistent analysis of anthropogenic pollution emissions at scales that is relevant to air quality, energy, and environmental policy. Here, we present three proof-of-concept studies that explore observational constraints from ground, aircraft, and satellite-derived measurements of atmospheric composition on bulk characteristics of anthropogenic combustion in megacities and fire regions. We focus on jointly analyzing co-emitted combustion products such as CO2, NO2, CO, SO2, and aerosols from GOSAT, OCO-2, OMI, MOPITT, and MODIS retrievals, in conjunction with USEPA AQS and NASA field campaigns. Each of these constituents exhibit distinct atmospheric signatures that depend on fuel type, combustion technology, process, practices and regulatory policies. Our results show that distinguishable patterns and relationships between the increases in concentrations across the megacity (or enhancements) due to emissions of these constituents enable us to: a) identify trends in combustion activity and efficiency, and b) reconcile discrepancies between state- to country-based emission inventories and modeled concentrations of these constituents. For example, the trends in enhancement ratios of these species reveal combustion emission pathways for China and United States that are not captured by current emission inventories and chemical reanalysis. Analysis of their joint distributions has considerable potential utility in current and future integrated constituent data assimilation and inverse modeling activities for monitoring, verifying, and reporting emissions, particularly for regions with few observations and limited information on local combustion processes. This work also motivates the need for continuous and preferably collocated satellite measurements of atmospheric composition, including CH4 and CO2, and studies related to improving the applicability and integration of these observations with ground- and aircraft- based

Ecophysiological adjustment of two Sphagnum species in response to anthropogenic nitrogen deposition.

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Wiedermann, Magdalena M; Gunnarsson, Urban; Ericson, Lars; Nordin, Annika

2009-01-01

Here, it was investigated whether Sphagnum species have adjusted their nitrogen (N) uptake in response to the anthropogenic N deposition that has drastically altered N-limited ecosystems, including peatlands, worldwide. A lawn species, Sphagnum balticum, and a hummock species, Sphagnum fuscum, were collected from three peatlands along a gradient of N deposition (2, 8 and 12 kg N ha(-1) yr(-1)). The mosses were subjected to solutions containing a mixture of four N forms. In each solution one of these N forms was labeled with (15)N (namely (15)NH(+)(4), (15)NO(-)(3) and the amino acids [(15)N]alanine (Ala) and [(15)N]glutamic acid (Glu)). It was found that for both species most of the N taken up was from , followed by Ala, Glu, and very small amounts from NO(-)(3). At the highest N deposition site N uptake was reduced, but this did not prevent N accumulation as free amino acids in the Sphagnum tissues. The reduced N uptake may have been genetically selected for under the relatively short period with elevated N exposure from anthropogenic sources, or may have been the result of plasticity in the Sphagnum physiological response. The negligible Sphagnum NO(-)(3) uptake may make any NO(-)(3) deposited readily available to co-occurring vascular plants.

Discriminating background from anthropogenic lead by isotopic methods

International Nuclear Information System (INIS)

Nelson, B.K.; O'Brien, H.E.

1995-01-01

The goal of this pilot project was to evaluate the practicality of using natural variations in the isotopic composition of lead to test for the presence of anthropogenic lead in soil, surface water and ground water. Complex chemical reactions in the environment may cause measured lead concentrations to be ambiguous indicators of anthropogenic lead component. The lead isotope tracer technique has the potential to identify both the presence and proportion of anthropogenic lead in the environment. The tested the lead isotope technique at Eielson Air Force Base, Alaska, on sources of suspected fuel contamination. Although the results are specific to this base, the general technique of using lead isotopes to trace the movement of anthropogenic lead is applicable to other CERCLA sites. The study had four objectives: (1) characterize the natural lead isotope composition of bedrock, stream sediment and soils; (2) characterize the isotopic composition of the contaminant lead derived from fuel; (3) evaluate the sensitivity of the isotopic method to distinguishing between anthropogenic and natural lead in soil and water samples and (4) evaluate the analytical feasibility and accuracy of the method at the Isotope Geochemistry Laboratory at the University of Washington

Anthropogenic impact and lead pollution throughout the Holocene in Southern Iberia.

Science.gov (United States)

García-Alix, A; Jimenez-Espejo, F J; Lozano, J A; Jiménez-Moreno, G; Martinez-Ruiz, F; García Sanjuán, L; Aranda Jiménez, G; García Alfonso, E; Ruiz-Puertas, G; Anderson, R Scott

2013-04-01

Present day lead pollution is an environmental hazard of global proportions. A correct determination of natural lead levels is very important in order to evaluate anthropogenic lead contributions. In this paper, the anthropogenic signature of early metallurgy in Southern Iberia during the Holocene, more specifically during the Late Prehistory, was assessed by mean of a multiproxy approach: comparison of atmospheric lead pollution, fire regimes, deforestation, mass sediment transport, and archeological data. Although the onset of metallurgy in Southern Iberia is a matter of controversy, here we show the oldest lead pollution record from Western Europe in a continuous paleoenvironmental sequence, which suggests clear lead pollution caused by metallurgical activities since ~3900 cal BP (Early Bronze Age). This lead pollution was especially important during Late Bronze and Early Iron ages. At the same time, since ~4000 cal BP, an increase in fire activity is observed in this area, which is also coupled with deforestation and increased erosion rates. This study also shows that the lead pollution record locally reached near present-day values many times in the past, suggesting intensive use and manipulation of lead during those periods in this area. Copyright © 2013 Elsevier B.V. All rights reserved.

Gridded anthropogenic emissions inventory and atmospheric transport of carbonyl sulfide in the U.S.: U.S. Anthropogenic COS Source and Transport

Energy Technology Data Exchange (ETDEWEB)

Zumkehr, Andrew [Sierra Nevada Research Institute, University of California, Merced California USA; Hilton, Timothy W. [Sierra Nevada Research Institute, University of California, Merced California USA; Whelan, Mary [Sierra Nevada Research Institute, University of California, Merced California USA; Smith, Steve [Joint Global Change Research Institute, PNNL, College Park Maryland USA; Campbell, J. Elliott [Sierra Nevada Research Institute, University of California, Merced California USA

2017-02-21

Carbonyl sulfide (COS or OCS), the most abundant sulfur containing gas in the troposphere, has recently emerged as a potentially important atmospheric tracer for the carbon cycle. Atmospheric inverse modeling studies may be able to use existing tower, airborne, and satellite observations of COS to infer information about photosynthesis. However, such analysis relies on gridded anthropogenic COS source estimates that are largely based on industry activity data from over three decades ago. Here we use updated emission factor data and industry activity data to develop a gridded inventory with a 0.1 degree resolution for the U.S. domain. The inventory includes the primary anthropogenic COS sources including direct emissions from the coal and aluminum industries as well as indirect sources from industrial carbon disulfide emissions. Compared to the previously published inventory, we found that the total anthropogenic source (direct and indirect) is 47% smaller. Using this new gridded inventory to drive the STEM/WRF atmospheric transport model, we found that the anthropogenic contribution to COS variation in the troposphere is small relative to the biosphere influence, which is encouraging of carbon cycle applications in this region. Additional anthropogenic sectors with highly uncertain emission factors require further field measurements.

Mercury profiles in sediment from the marginal high of Arabian Sea: An indicator of increasing anthropogenic Hg input

Digital Repository Service at National Institute of Oceanography (India)

Chakraborty, P.; Vudamala, K.; Chennuri, K.; Armoury, K.; Linsy, P.; Ramteke, D.; Sebastian, T.; Jayachandran, S.; Naik, C.; Naik, R.; Nath, B.N.

provided the sediments remain undisturbed by either natural or anthropogenic forces (Engstrom et al. 2007). However, it has also been suggested that early diagenesis in sediment column may increase mobility of Hg and can alter concentration profile of Hg... the mobility of Hg in sediment (Dehairq 1989; Gagnon and Mucci 1997; van der Zee and van Raaphorst 2004; Konovalov et al. 2007). Oxidation of sedimentary organic matter also appears to release significant amounts of mercury (associated with organic phase...

Assessment of the effect of anthropogenic pollution on the ecology of small shallow lakes using the palaeolimnological approach

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Tiiu Koff

2016-11-01

Full Text Available Palaeolimnological techniques were utilized to determine the extent of the effect of anthropogenic pollutants or other environmental stressors on three lake ecosystems over the last 200 years. The ecology of the study sites has experienced significant changes due to various activities such as (1 extensive catchment drainage and using poisoning as a fish management measure, (2 seepage of urban waste water due to establishment and growth of a town and (3 artificial inflow of oil-shale mining waters. Sediment geochemical composition, fossil pigments and Cladocera remains from the sediment cores were analysed to demonstrate that sufficient information can be derived from sediments to permit a historical reconstruction. The integrated use of archival maps, historical records and lake monitoring data confirmed links to anthropogenic pollutants, primarily on the catchment level. The examples show how the sediment indicators provide unique insights into the causes and temporal dynamics of lake ecosystem changes relevant for environmental management decisions. This study demonstrates that palaeolimnology has great potential to assist in eutrophication assessment and management efforts in waterbodies.

Reconstructing Colonization Dynamics of the Human Parasite Schistosoma mansoni following Anthropogenic Environmental Changes in Northwest Senegal

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Van den Broeck, Frederik; Maes, Gregory E.; Larmuseau, Maarten H. D.; Rollinson, David; Sy, Ibrahima; Faye, Djibril; Volckaert, Filip A. M.; Polman, Katja; Huyse, Tine

2015-01-01

Background Anthropogenic environmental changes may lead to ecosystem destabilization and the unintentional colonization of new habitats by parasite populations. A remarkable example is the outbreak of intestinal schistosomiasis in Northwest Senegal following the construction of two dams in the ‘80s. While many studies have investigated the epidemiological, immunological and geographical patterns of Schistosoma mansoni infections in this region, little is known about its colonization history. Methodology/Principal Findings Parasites were collected at several time points after the disease outbreak and genotyped using a 420 bp fragment of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) and nine nuclear DNA microsatellite markers. Phylogeographic and population genetic analyses revealed the presence of (i) many genetically different haplotypes at the non-recombining mitochondrial marker and (ii) one homogenous S. mansoni genetic group at the recombining microsatellite markers. These results suggest that the S. mansoni population in Northwest Senegal was triggered by intraspecific hybridization (i.e. admixture) between parasites that were introduced from different regions. This would comply with the extensive immigration of infected seasonal agricultural workers from neighboring regions in Senegal, Mauritania and Mali. The spatial and temporal stability of the established S. mansoni population suggests a swift local adaptation of the parasite to the local intermediate snail host Biomphalaria pfeifferi at the onset of the epidemic. Conclusions/Significance Our results show that S. mansoni parasites are very successful in colonizing new areas without significant loss of genetic diversity. Maintaining high levels of diversity guarantees the adaptive potential of these parasites to cope with selective pressures such as drug treatment, which might complicate efforts to control the disease. PMID:26275049

Potential for spatial displacement of Cook Inlet beluga whales by anthropogenic noise in critical habitat

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Small, Robert J.; Brost, Brian M.; Hooten, Mevin B.; Castellote, Manuel; Mondragon, Jeffrey

2017-01-01

The population of beluga whales in Cook Inlet, Alaska, USA, declined by nearly half in the mid-1990s, primarily from an unsustainable harvest, and was listed as endangered in 2008. In 2014, abundance was ~340 whales, and the population trend during 1999-2014 was -1.3% yr-1. Cook Inlet beluga whales are particularly vulnerable to anthropogenic impacts, and noise that has the potential to reduce communication and echolocation range considerably has been documented in critical habitat; thus, noise was ranked as a high potential threat in the Cook Inlet beluga Recovery Plan. The current recovery strategy includes research on effects of threats potentially limiting recovery, and thus we examined the potential impact of anthropogenic noise in critical habitat, specifically, spatial displacement. Using a subset of data on anthropogenic noise and beluga detections from a 5 yr acoustic study, we evaluated the influence of noise events on beluga occupancy probability. We used occupancy models, which account for factors that affect detection probability when estimating occupancy, the first application of these models to examine the potential impacts of anthropogenic noise on marine mammal behavior. Results were inconclusive, primarily because beluga detections were relatively infrequent. Even though noise metrics (sound pressure level and noise duration) appeared in high-ranking models as covariates for occupancy probability, the data were insufficient to indicate better predictive ability beyond those models that only included environmental covariates. Future studies that implement protocols designed specifically for beluga occupancy will be most effective for accurately estimating the effect of noise on beluga displacement.

Retrospective biomonitoring of chemical contamination in the marine coastal environment of Terra Nova Bay (Ross Sea, Antarctica) by environmental specimen banking.

Science.gov (United States)

Grotti, Marco; Pizzini, Sarah; Abelmoschi, Maria Luisa; Cozzi, Giulio; Piazza, Rossano; Soggia, Francesco

2016-12-01

Antarctica offers a good opportunity to investigate planetary-scale pollution and climate change, and provides baseline values for contaminants such as Trace Elements (TEs) and Persistent Organic Pollutants (POPs). Literature data on contaminant levels in the Antarctic environment indicate that long-range atmospheric transport is the primary pathway by which pollutants from surrounding continents are carried to this pristine environment. However, local contamination sources represented by the scientific stations are also not negligible. Climate change and global warming are altering the global budget of anthropogenic contaminants and their monitoring in Antarctica ecosystems is very important to protect the global environment. In this work, eighty specimens of Adamussium colbecki (Smith, 1902), a benthic Antarctic scallop, collected from 1996 to 2009 and stored in the Antarctic Environmental Specimen Bank, were analyzed to quantify TEs and POPs, including polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and polycyclic aromatic hydrocarbons (PAHs). Metals concentrations were not affected by anthropogenic contributions, highlighting a natural accumulation with the age of the organism. Similarly, no temporal trend was found for PCNs, PCBs and PAHs. However, specimens collected during the summer 1997-98 showed enhanced concentration levels of PCBs and PAHs that could refer to a local anthropogenic source of contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluating the adequacy of a reference site pool for ecological assessments in environmentally complex regions

Science.gov (United States)

Ode, Peter R.; Rehn, Andrew C.; Mazor, Raphael D.; Schiff, Kenneth C.; Stein, Eric D.; May, Jason; Brown, Larry R.; Herbst, David B.; Gillette, D.D.; Lunde, Kevin; Hawkins, Charles P.

2016-01-01

Many advances in the field of bioassessment have focused on approaches for objectively selecting the pool of reference sites used to establish expectations for healthy waterbodies, but little emphasis has been placed on ways to evaluate the suitability of the reference-site pool for its intended applications (e.g., compliance assessment vs ambient monitoring). These evaluations are critical because an inadequately evaluated reference pool may bias assessments in some settings. We present an approach for evaluating the adequacy of a reference-site pool for supporting biotic-index development in environmentally heterogeneous and pervasively altered regions. We followed common approaches for selecting sites with low levels of anthropogenic stress to screen 1985 candidate stream reaches to create a pool of 590 reference sites for assessing the biological integrity of streams in California, USA. We assessed the resulting pool of reference sites against 2 performance criteria. First, we evaluated how well the reference-site pool represented the range of natural gradients present in the entire population of streams as estimated by sites sampled through probabilistic surveys. Second, we evaluated the degree to which we were successful in rejecting sites influenced by anthropogenic stress by comparing biological metric scores at reference sites with the most vs fewest potential sources of stress. Using this approach, we established a reference-site pool with low levels of human-associated stress and broad coverage of environmental heterogeneity. This approach should be widely applicable and customizable to particular regional or programmatic needs.

Seasonal variations in the sources of natural and anthropogenic lead deposited at the East Rongbuk Glacier in the high-altitude Himalayas

International Nuclear Information System (INIS)

Burn-Nunes, Laurie; Vallelonga, Paul; Lee, Khanghyun; Hong, Sungmin; Burton, Graeme; Hou, Shugui; Moy, Andrew; Edwards, Ross; Loss, Robert; Rosman, Kevin

2014-01-01

Lead (Pb) isotopic compositions and concentrations, and barium (Ba) and indium (In) concentrations have been analysed at sub-annual resolution in three sections from a < 110 m ice core dated to the 18th and 20th centuries, as well as snow pit samples dated to 2004/2005, recovered from the East Rongbuk Glacier in the high-altitude Himalayas. Ice core sections indicate that atmospheric chemistry prior to ∼ 1953 was controlled by mineral dust inputs, with no discernible volcanic or anthropogenic contributions. Eighteenth century monsoon ice core chemistry is indicative of dominant contributions from local Himalayan sources; non-monsoon ice core chemistry is linked to contributions from local (Himalayan), regional (Indian/Thar Desert) and long-range (North Africa, Central Asia) sources. Twentieth century monsoon and non-monsoon ice core data demonstrate similar seasonal sources of mineral dust, however with a transition to less-radiogenic isotopic signatures that suggests local and regional climate/environmental change. The snow pit record demonstrates natural and anthropogenic contributions during both seasons, with increased anthropogenic influence during non-monsoon times. Monsoon anthropogenic inputs are most likely sourced to South/South-East Asia and/or India, whereas non-monsoon anthropogenic inputs are most likely sourced to India and Central Asia. - Highlights: • Pb isotopes in ice and snow show seasonality in Mt Everest atmospheric chemistry. • Local (Himalayan) mineral dust inputs are present year round. • Regional and long-range mineral dust inputs are evident during non-monsoon times. • Snow samples indicate increased anthropogenic inputs during non-monsoon times. • Anthropogenic inputs are linked with Indian, South Asian and Central Asian sources

Seasonal variations in the sources of natural and anthropogenic lead deposited at the East Rongbuk Glacier in the high-altitude Himalayas

Energy Technology Data Exchange (ETDEWEB)

Burn-Nunes, Laurie, E-mail: L.Nunes@curtin.edu.au [Department of Imaging and Applied Physics, Curtin University, GPO Box U 1987, Perth 6845, Western Australia (Australia); Vallelonga, Paul [Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen Ø (Denmark); Lee, Khanghyun [Environmental Measurement and Analysis Center, National Institute of Environmental Research, Environmental Research Complex, Kyungseo-dong, Seo-gu, Incheon 404-170 (Korea, Republic of); Hong, Sungmin [Department of Ocean Sciences, Inha University, 100 Inha-ro, Nam-gu, Incheon 402-751 (Korea, Republic of); Burton, Graeme [Department of Imaging and Applied Physics, Curtin University, GPO Box U 1987, Perth 6845, Western Australia (Australia); Hou, Shugui [Key Laboratory of Coast and Island development of Ministry of Education, School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210093 (China); Moy, Andrew [Department of the Environment, Australian Antarctic Division, Channel Highway, Kingston 7050, Tasmania (Australia); Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Private Bag 80, Hobart 7001, Tasmania (Australia); Edwards, Ross; Loss, Robert; Rosman, Kevin [Department of Imaging and Applied Physics, Curtin University, GPO Box U 1987, Perth 6845, Western Australia (Australia)

2014-07-01

Lead (Pb) isotopic compositions and concentrations, and barium (Ba) and indium (In) concentrations have been analysed at sub-annual resolution in three sections from a < 110 m ice core dated to the 18th and 20th centuries, as well as snow pit samples dated to 2004/2005, recovered from the East Rongbuk Glacier in the high-altitude Himalayas. Ice core sections indicate that atmospheric chemistry prior to ∼ 1953 was controlled by mineral dust inputs, with no discernible volcanic or anthropogenic contributions. Eighteenth century monsoon ice core chemistry is indicative of dominant contributions from local Himalayan sources; non-monsoon ice core chemistry is linked to contributions from local (Himalayan), regional (Indian/Thar Desert) and long-range (North Africa, Central Asia) sources. Twentieth century monsoon and non-monsoon ice core data demonstrate similar seasonal sources of mineral dust, however with a transition to less-radiogenic isotopic signatures that suggests local and regional climate/environmental change. The snow pit record demonstrates natural and anthropogenic contributions during both seasons, with increased anthropogenic influence during non-monsoon times. Monsoon anthropogenic inputs are most likely sourced to South/South-East Asia and/or India, whereas non-monsoon anthropogenic inputs are most likely sourced to India and Central Asia. - Highlights: • Pb isotopes in ice and snow show seasonality in Mt Everest atmospheric chemistry. • Local (Himalayan) mineral dust inputs are present year round. • Regional and long-range mineral dust inputs are evident during non-monsoon times. • Snow samples indicate increased anthropogenic inputs during non-monsoon times. • Anthropogenic inputs are linked with Indian, South Asian and Central Asian sources.

Isotopic fingerprints of anthropogenic molybdenum in lake sediments.

Science.gov (United States)

Chappaz, Anthony; Lyons, Timothy W; Gordon, Gwyneth W; Anbar, Ariel D

2012-10-16

We measured the molybdenum isotope compositions (δ(98)Mo) of well-dated sediment cores from two lakes in eastern Canada in an effort to distinguish between natural and anthropogenic contributions to these freshwater aquatic systems. Previously, Chappaz et al. (1) ascribed pronounced 20th-century Mo concentration enrichments in these lakes to anthropogenic inputs. δ(98)Mo values in the deeper sediments (reflecting predominantly natural Mo sources) differ dramatically between the two lakes: -0.32 ± 0.17‰ for oxic Lake Tantare and +0.64 ± 0.09‰ for anoxic Lake Vose. Sediment layers previously identified as enriched in anthropogenic Mo, however, reveal significant δ(98)Mo shifts of ± 0.3‰, resulting in isotopically heavier values of +0.05 ± 0.18‰ in Lake Tantare and lighter values of +0.31 ± 0.03‰ in Lake Vose. We argue that anthropogenic Mo modifies the isotopic composition of the recent sediments, and we determine δ(98)Mo(anthropogenic) values of 0.1 ± 0.1‰ (Lake Vose) and 0.2 ± 0.2‰ (Lake Tantare). These calculated inputs are consistent with the δ(98)Mo of molybdenite (MoS(2)) likely delivered to the lakes via smelting of porphyry copper deposits (Lake Vose) or through combustion of coal and oil also containing Mo (Lake Tantare). Our results confirm the utility of Mo isotopes as a promising fingerprint of human impacts and perhaps the specific sources of contamination. Importantly, the magnitudes of the anthropogenic inputs are large enough, relative to the natural Mo cycles in each lake, to have an impact on the microbiological communities.

Anthropogenic effect on avalanche and debris flow activity

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S. A. Sokratov

2013-01-01

Full Text Available The paper presents examples of the change in snow avalanches and debris flows activity due to the anthropogenic pressure on vegetation and relief. The changes in dynamical characteristics of selected snow avalanches and debris flows due to the anthropogenic activity are quantified. The conclusion is made that the anthropogenic effects on the snow avalanches and debris flows activity are more pronounced than the possible effects of the climate change. The necessity is expressed on the unavoidable changes of the natural environment as the result of a construction and of use of the constructed infrastructure to be account for in corresponding planning of the protection measures.

Changes in the acoustic environment alter the foraging and sheltering behaviour of the cichlid Amititlania nigrofasciata.

Science.gov (United States)

McLaughlin, Kirsty Elizabeth; Kunc, Hansjoerg P

2015-07-01

Anthropogenic noise can affect behaviour across a wide range of species in both terrestrial and aquatic environments. However, behaviours might not be affected in isolation. Therefore, a more holistic approach investigating how environmental stressors, such as noise pollution, affect different behaviours in concert is necessary. Using tank-based noise exposure experiments, we tested how changes in the acoustic environment affect the behaviour of the cichlid Amatitlania nigrofasciata. We found that exposure to anthropogenic noise affected a couple of behaviours: an increase in sheltering was accompanied by a decrease in foraging. Our results highlight the multiple negative effects of an environmental stressor on an individual's behaviour. Copyright © 2015 Elsevier B.V. All rights reserved.

Assessment of the fate of anthropogenic nitrogen in large watersheds by isotopic techniques

International Nuclear Information System (INIS)

Mayer, B.

1999-01-01

Human activity has greatly altered the nitrogen cycle in terrestrial and aquatic ecosystems and increased the nitrogen flow in many rivers. Preliminary work of the International SCOPE Nitrogen Project indicates that only 20% of the human-controlled nitrogen inputs to large watersheds are exported to the oceans in riverine flow (Howarth, 1998). Therefore, approximately 80% of the anthropogenic nitrogen inputs are either stored or denitrified in the catchments. Anthropogenic nitrogen can be retained in forests (possibly as a result of increased productivity) or in agricultural soils. It can also be stored in groundwater. These sinks are, however, often not large enough to account for the 'missing' nitrogen. It is, therefore, assumed that the majority of the human-controlled nitrogen inputs to large watersheds is denitrified in soils, riparian zones, wetlands, lakes, and rivers. Within the SCOPE Nitrogen Project, preliminary isotope analyses were performed on dissolved nitrates from several streams draining into the North Atlantic Ocean. Both δ 15 N nitrate and δ 18 O nitrate values were determined in order to identify nitrate sources. A further objective was to test, whether the isotopic composition of dissolved nitrate provides a measure for the extent to which denitrification occurs in the respective watersheds

Spring flood pH decline in northern Sweden: Towards an operational model separating natural acidity from anthropogenic acidification

Energy Technology Data Exchange (ETDEWEB)

Laudon, H.

1999-10-01

The spring flood is a defining feature of the ecosystem in northern Sweden. In this region, spring flood is an occasion for dramatic hydrochemical changes that profoundly effect the biodiversity of the aquatic ecosystem. Spring flood is also the period most susceptible to anthropogenic acidification. A belief in the anthropogenic component to pH decline during spring flood has been an important factor in spending over half a billion crowns to lime surface waters in Northern Sweden during the last decade. The natural component of episodic pH decline during spring flood, however, has received less attention. The main objective of this work is to present an operational model for separating and quantifying the anthropogenic and natural contributions of episodic acidification during high flow events in Northern Sweden. The key assumptions in this model are that baseflow ANC has not been affected by anthropogenic acidification, that DOC has not changed due to modern land-use practice and that natural dilution during hydrological episodes can be quantified. The limited data requirements of 10-15 stream water samples before and during spring flood make the model suitable for widespread use in environmental monitoring programs. This makes it possible to distinguish trends of human impact as well as natural pH decline in space and time. Modeling results from northern Sweden demonstrate that the natural driving mechanisms of dilution and organic acidity were the dominant factors in the episodic acidification of spring flood in the region. The anthropogenic contribution to spring pH decline was similar in size to the natural contribution in only two of the more than 30 events where this model was applied. Natural factors alone were found to cause pH values below 4.5 in some streams. Anthropogenic sources of acidity can be superimposed on this natural dynamics. In the sites studied, the magnitude of the anthropogenic ANC decline was correlated to the winter deposition of

Blue whales respond to anthropogenic noise.

Directory of Open Access Journals (Sweden)

Mariana L Melcón

Full Text Available Anthropogenic noise may significantly impact exposed marine mammals. This work studied the vocalization response of endangered blue whales to anthropogenic noise sources in the mid-frequency range using passive acoustic monitoring in the Southern California Bight. Blue whales were less likely to produce calls when mid-frequency active sonar was present. This reduction was more pronounced when the sonar source was closer to the animal, at higher sound levels. The animals were equally likely to stop calling at any time of day, showing no diel pattern in their sensitivity to sonar. Conversely, the likelihood of whales emitting calls increased when ship sounds were nearby. Whales did not show a differential response to ship noise as a function of the time of the day either. These results demonstrate that anthropogenic noise, even at frequencies well above the blue whales' sound production range, has a strong probability of eliciting changes in vocal behavior. The long-term implications of disruption in call production to blue whale foraging and other behaviors are currently not well understood.

A Study Of Environmental Impacts On The Coral Resources In The Vicinity Of The Saint Martin Island Bangladesh

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Shaikh Sayed Ahammed

2015-08-01

Full Text Available A study of the environmental impacts on the coral resources in the vicinity of the Saint Martin Island Bangladesh was conducted with a view to making an assessment of the current status of coral resources in the island and identifying major natural and anthropogenic environmental threats to the future sustainability of these resources. It is evident that the coral resources have been reduced significantly and currently only 41 coral species are available. The existing environmental condition assessed by pH salinity turbidity and temperature in the island is not found responsible for the survival of the corals. The study also reveals that the major anthropogenic interventions are responsible for the gradual depletion of the coral resources. The major anthropogenic threats to the coral resources are coral collection and overfishing. In addition coral extraction is identified as a potential threat to the future integrity of coral communities in the island. Environmental threats from anthropogenic activities related to sedimentation land erosion and pollution are also the concerns for the coral communities in the island. For the conservation of the coral population no coral monitoring cell has been established in this island.

Chironomidae traits and life history strategies as indicators of anthropogenic disturbance.

Science.gov (United States)

Serra, Sónia R Q; Graça, Manuel A S; Dolédec, Sylvain; Feio, Maria João

2017-07-01

In freshwater ecosystems, Chironomidae are currently considered indicators of poor water quality because the family is often abundant in degraded sites. However, it incorporates taxa with a large ecological and physiological diversity and different sensitivity to impairment. Yet, the usual identification of Chironomidae at coarse taxonomic levels (family or subfamily) masks genus and species sensitivities. In this study, we investigate the potential of taxonomic and functional (traits) composition of Chironomidae to detect anthropogenic disturbance. In this context, we tested some a priori hypotheses regarding the ability of Chironomidae taxonomic and trait compositions to discriminate Mediterranean streams affected by multiple stressors from least-disturbed streams. Both taxonomic and Eltonian trait composition discriminated sites according to their disturbance level. Disturbance resulted in the predicted increase of Chironomidae with higher number of stages with hibernation/diapause and of taxa with resistance forms and unpredicted increase of the proportion of taxa with longer life cycles and few generations per year. Life history strategies (LHS), corresponding to multivoltine Chironomidae that do not invest in hemoglobin and lack strong spring synchronization, were well adapted to all our Mediterranean sites with highly changeable environmental conditions. Medium-size animals favored in disturbed sites where the Mediterranean hydrological regime is altered, but the reduced number of larger-size/carnivore Chironomids suggests a limitation to secondary production. Results indicate that Chironomidae genus and respective traits could be a useful tool in the structural and functional assessment of Mediterranean streams. The ubiquitous nature of Chironomidae should be also especially relevant in the assessment of water bodies naturally poor in other groups such as the Ephemeroptera, Plecoptera, and Trichoptera, such as the lowland rivers with sandy substrates, lakes

Anthropogenic changes in environmental conditions of phytocoenoses of medium sized-sized Ukrainian river valleys (based on the example of the River Tyasmyn – a tributary of the Dnieper

Directory of Open Access Journals (Sweden)

V. V. Lavrov

2016-09-01

Full Text Available The problem of anthropogenic degradation of rivers is usually marked by its multi-sectoral and often international character as well by the large number of sources of environmental threat. Therefore, its solution requires a systematic approach based on transparent and coordinated interagency and international cooperation. The River Dnieper inUkrainehas undergone a remarkable transformation as a result of the construction of a cascade of reservoirs. Anthropogenic damage to the plants and soil that cover its basin have caused damage to the functioning of ecological regimes of theDnieper’s tributaries. Small and medium-sized rivers are dying. In this article, attention is paid to a typical middle-sized (164 km river of theDnieperBasin, the Tyasmyn. Its middle and lower parts are located in the overtransformed Irdyn-Tyasmyn valley. During the last glaciation it formed the central part of the right arm of the ancientDnieper. Regulation of the Tyasmyn runoff, pollution, the creation of theKremenchugreservoir on theDnieper, grazing and recreational load have led to the threat of the river degrading. Therefore, the aim of this article is to characterize the structure of the herbaceous vegetation in the central and lower parts of the Tyasmyn valley and assess the level of its dependence on anthropogenic changes in the conditions of the ecotypes. The methods used are: retrospective and system analysis, comparative ecology (ecological profile or transect, botanic methods, phytoindication, the mapping method and mathematical statistics. The features of changes in environmental conditions of ecotypes of the river valley have been shown through systematic, biomorphological, ecomorphic structure of the herbaceous cover, the ratio of ecological groups and changes in types of ecological strategy of species, phytodiversity. We found 89 species of vascular plants. The most diverse families were Asteraceae, Poaceae and Lamiaceae. The biomorphological range of

ANTHROPOGENIC ACTIVITIES THREATENING THE ...

African Journals Online (AJOL)

Osondu

2012-02-17

Feb 17, 2012 ... anthropogenic activities across the protected areas in the country. ... education and provision of fund to support sustainable livelihood practices. ... wildlife conservation and tourism. ... Fig: 1 Map of Oyo State showing location of Old Oyo National Park and adjoining community. #. #. # .... This was the view of.

The influence of production conditions, starting material and deposition environment on charcoal alteration in a tropical biome.

Science.gov (United States)

Ascough, Philippa; Bird, Michael; Meredith, Will; Large, David; Snape, Colin; Manion, Corinne

2014-05-01

Natural and anthropogenic burning events are a key link in the global carbon cycle, substantially influencing atmospheric CO2 levels, and consuming c.8700 teragrams yr-1 of dry biomass [1,2,3]. An important result of this process is charcoal, when lignocellulosic structures in biomass (e.g. wood) are converted to aromatic domains with high chemical stability. Charcoal is therefore not readily re-oxidized to CO2, with estimates of 5-7 ky for the half-life of charcoal carbon in soils [3,4]. Charcoal's high carbon content coupled with high environmental resistance has led to the concept of biochar as a valuable means of global carbon sequestration, capable of carbon offsets comparable to annual anthropogenic fuel emissions [5,6,7]. Charcoal is not, however, an environmentally inert substance, and at least some components of charcoal are susceptible to alteration in depositional environments. Despite the importance of charcoal in global carbon cycling, the mechanisms by which charcoal is altered in the environment remain, as yet, poorly understood. This fact limits our ability to properly incorporate both natural environmental charcoal and biochar into global carbon budgets. This study aimed to improve understanding of charcoal alteration in the environment by examining the influence of production conditions, starting material and deposition environment on the physical and chemical characteristics of charcoal at a field site in the Daintree rainforest. These factors have been identified as critical in determining the dynamics of charcoal in depositional environments [8,9] and climatic conditions at the field site (in Tropical Queensland, Australia) are likely to result in extensive alteration of charcoal. Charcoal from wood (Nothofagus spp.), algae (Enteromorpha spp.), and sugarcane (Saccharum spp.) biomass was produced at temperatures over 300-500°C and exposed to conditions of varying pH and vegetation cover. The effect of these variables on charcoal chemistry

Environmental parameters altered by climate change affect the activity of soil microorganisms involved in bioremediation.

Science.gov (United States)

Alkorta, Itziar; Epelde, Lur; Garbisu, Carlos

2017-10-16

Bioremediation, based on the use of microorganisms to break down pollutants, can be very effective at reducing soil pollution. But the climate change we are now experiencing is bound to have an impact on bioremediation performance, since the activity and degrading abilities of soil microorganisms are dependent on a series of environmental parameters that are themselves being altered by climate change, such as soil temperature, moisture, amount of root exudates, etc. Many climate-induced effects on soil microorganisms occur indirectly through changes in plant growth and physiology derived from increased atmospheric CO2 concentrations and temperatures, the alteration of precipitation patterns, etc., with a concomitant effect on rhizoremediation performance (i.e. the plant-assisted microbial degradation of pollutants in the rhizosphere). But these effects are extremely complex and mediated by processes such as acclimation and adaptation. Besides, soil microorganisms form complex networks of interactions with a myriad of organisms from many taxonomic groups that will also be affected by climate change, further complicating data interpretation. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Assessment of global industrial-age anthropogenic arsenic contamination.

Science.gov (United States)

Han, Fengxiang X; Su, Yi; Monts, David L; Plodinec, M John; Banin, Amos; Triplett, Glover E

2003-09-01

Arsenic, a carcinogenic trace element, threatens not only the health of millions of humans and other living organisms, but also global sustainability. We present here, for the first time, the global industrial-age cumulative anthropogenic arsenic production and its potential accumulation and risks in the environment. In 2000, the world cumulative industrial-age anthropogenic arsenic production was 4.53 million tonnes. The world-wide coal and petroleum industries accounted for 46% of global annual gross arsenic production, and their overall contribution to industrial-age gross arsenic production was 27% in 2000. Global industrial-age anthropogenic As sources (as As cumulative production) follow the order: As mining production>As generated from coal>As generated from petroleum. The potential industrial-age anthropogenic arsenic input in world arable surface in 2000 was 2.18 mg arsenic kg(-1), which is 1.2 times that in the lithosphere. The development of substitute materials for arsenic applications in the agricultural and forestry industries and controls of arsenic emissions from the coal industry may be possible strategies to significantly decrease arsenic pollution sources and dissipation rates into the environment.

German-Egyptian seminar on environmental research

International Nuclear Information System (INIS)

Aly, H.F.; Nentwich, D.

1994-01-01

Industrial development and scientific advancement have opened new frontiers of interest and challenges. Anthropogenic activities are increasingly upsetting the natural environmental balance and are at the same time shifting from local impact to global importance. Science is confronted with the challenge to answer the question of what are the consequences of anthropogenic changes to the environment and to help politics formulate countermeasures for the sake of a sustainable future. Protect results achieved within the Egyptian-German cooperation were presented to the scientific community and to the interested public and discussions on future lines of actions took place. (orig./KW)

Fate of linear alkylbenzenes and benzothiazoles of anthropogenic origin and their potential as environmental molecular markers in the Pearl River Delta, South China

International Nuclear Information System (INIS)

Ni Honggang; Shen Rulang; Zeng Hui; Zeng, Eddy Y.

2009-01-01

The mass emissions of linear alkylbenzenes (LABs), benzothiazole (BT), and 2-[4-morpholinyl]benzothiazole (24MoBT) from anthropogenic activities within one year were estimated according to the population and the number of automobiles in the Pearl River Delta (PRD), South China. Based on the estimation, the distribution of these compounds among various environmental media was simulated with a mass balance box model established in the present study. The results showed that 79% of LABs generated in the PRD was stored in sediment while only 1.3% of LABs was presumably transported to the adjacent South China Sea (SCS). On the contrary, 47% of BT and 77% of 24MoBT generated in the region were carried with riverine runoff to the coastal ocean. The results from the present study suggest that hydrophobic compounds tend to stay in the watershed of the PRD, whereas hydrophilic ones mainly outflow to the coastal ocean. - A simple mass balance box model examines the fate of linear alkylbenzenes and benzothiazoles in the Pearl River Delta, South China.

Conundrums, paradoxes, and surprises: a brave new world of biodiversity conservation

Science.gov (United States)

A.E. Lugo

2012-01-01

Anthropogenic activity is altering the global disturbance regime through such processes as urbanization, deforestation, and climate change. These disturbance events alter the environmental conditions under which organisms live and adapt and trigger succession, thus setting the biota in otiion in both ecological and evolutionary space. The result is the mixing of...

Anthropogenic phosphorus (P) inputs to a river basin and their impacts on P fluxes along its upstream-downstream continuum

Science.gov (United States)

Zhang, Wangshou; Swaney, Dennis; Hong, Bongghi; Howarth, Robert

2017-04-01

Phosphorus (P) originating from anthropogenic sources as a pollutant of surface waters has been an environmental issue for decades because of the well-known role of P in eutrophication. Human activities, such as food production and rapid urbanization, have been linked to increased P inputs which are often accompanied by corresponding increases in riverine P export. However, uneven distributions of anthropogenic P inputs along watersheds from the headwaters to downstream reaches can result in significantly different contributions to the riverine P fluxes of a receiving water body. So far, there is still very little scientific understanding of anthropogenic P inputs and their impacts on riverine flux in river reaches along the upstream to downstream continuum. Here, we investigated P budgets in a series of nested watersheds draining into Hongze Lake of China, and developed a simple empirical function to describe the relationship between anthropogenic inputs and riverine TP fluxes. The results indicated that an average of 1.1% of anthropogenic P inputs are exported into rivers, with most of the remainder retained in the watershed landscape over the period studied. Fertilizer application was the main contributor of P loading to the lake (55% of total loads), followed by legacy P stock (30%), food and feed P inputs (12%) and non-food P inputs (4%). From 60% to 89% of the riverine TP loads generated from various locations within this basin were ultimately transported into the receiving lake of the downstream, with an average rate of 1.86 tons P km-1 retaining in the main stem of the inflowing river annually. Our results highlight that in-stream processes can significantly buffer the riverine P loading to the downstream receiving lake. An integrated P management strategy considering the influence of anthropogenic inputs and hydrological interactions is required to assess and optimize P management for protecting fresh waters.

Modelling of anthropogenic and natural climate changes

Energy Technology Data Exchange (ETDEWEB)

Grassl, H; Mikolajewicz, U; Bakan, S [Max Planck Institute of Meteorology, Hamburg (Germany)

1993-06-01

The delay of anthropogenic climate change caused by oceans and other slowly reacting climate system components forces us to numerical modeling as the basis of decisions. For three three-dimensional numerical examples, namely transient coupled ocean-atmosphere models for the additional greenhouse effect, internal ocean-atmosphere variability, and disturbance by soot particles from burning oil wells, the present-day status is described. From all anthropogenic impacts on the radiative balance, the contribution from trace gases is the most important.

Development of a dietary environmental index to assess nutritional quality versus environmental effect of foods and dietary patterns

Science.gov (United States)

Background: Anthropogenic environmental effects of food production and processing, alongside diets that fail to meet nutritional requirements, are contributing to an unhealthy as well as unsustainable food system. Going forward it is crucial that nutritional health be considered alongside the ecolog...

Changing expression of vertebrate immunity genes in an anthropogenic environment: a controlled experiment.

Science.gov (United States)

Hablützel, Pascal I; Brown, Martha; Friberg, Ida M; Jackson, Joseph A

2016-09-01

The effect of anthropogenic environments on the function of the vertebrate immune system is a problem of general importance. For example, it relates to the increasing rates of immunologically-based disease in modern human populations and to the desirability of identifying optimal immune function in domesticated animals. Despite this importance, our present understanding is compromised by a deficit of experimental studies that make adequately matched comparisons between wild and captive vertebrates. We transferred post-larval fishes (three-spined sticklebacks), collected in the wild, to an anthropogenic (captive) environment. We then monitored, over 11 months, how the systemic expression of immunity genes changed in comparison to cohort-matched wild individuals in the originator population (total n = 299). We found that a range of innate (lyz, defbl2, il1r-like, tbk1) and adaptive (cd8a, igmh) immunity genes were up-regulated in captivity, accompanied by an increase in expression of the antioxidant enzyme, gpx4a. For some genes previously known to show seasonality in the wild, this appeared to be reduced in captive fishes. Captive fishes tended to express immunity genes, including igzh, foxp3b, lyz, defbl2, and il1r-like, more variably. Furthermore, although gene co-expression patterns (analyzed through gene-by-gene correlations and mutual information theory based networks) shared common structure in wild and captive fishes, there was also significant divergence. For one gene in particular, defbl2, high expression was associated with adverse health outcomes in captive fishes. Taken together, these results demonstrate widespread regulatory changes in the immune system in captive populations, and that the expression of immunity genes is more constrained in the wild. An increase in constitutive systemic immune activity, such as we observed here, may alter the risk of immunopathology and contribute to variance in health in vertebrate populations exposed to

Copper alloys deterioration due to anthropogenic action

Energy Technology Data Exchange (ETDEWEB)

Duran, A.; Perez-Rodriguez, J. L.; Herrera, L. K.; Jimenez-de-Haro, M. C.; Robador, M. D.; Justo, A.; Blanes, J. M.; Perez-Ferrer, J. C.

2008-07-01

Results are presented from several samples taken from leaves of the Pardon Portico of Mosque-Cathedral or Cordoba, where an alteration on their surface was detected. Metal samples analyzed using X-ray microanalysis and powder x-ray diffraction were predominantly constituted by copper with some amounts of zinc attributed to brass, whereas other samples were also constituted by copper, tin and lead attributed to bronze. surface samples were analyzed using the same techniques. In addition Fourier transform infrared spectroscopy was also used. The main compound identified in all the surface of the leaves is copper chloride hydroxide (atacamite). Lead chlorides have also been found. These data show that the sudden alteration that appears may be attributed to the use of some cleaning product containing chloride. Other compounds detected in the surface were gypsum, quartz and oxalates coming from environmental contamination. (Author) 17 refs.

Anthropogenic features and hillslope processes interaction

Science.gov (United States)

Tarolli, Paolo; Sofia, Giulia

2016-04-01

Topography emerges as a result of natural driving forces, but some human activities (such as mining, agricultural practices and the construction of road networks) directly or indirectly move large quantities of soil, which leave clear topographic signatures embedded on the Earth's morphology. These signatures can cause drastic changes to the geomorphological organization of the landscape, with direct consequences on Earth surface processes (Tarolli and Sofia, 2016). To this point, the present research investigates few case studies highlighting the influences of anthropogenic topographic signatures on hillslope processes, and it shows the effectiveness of High-Resolution Topography (HRT) derived from the recent remote sensing technologies (e.g. lidar, satellite, structure from motion photogrammetry), to better understand this interaction. The first example is related to agricultural terraces. In recent times, terraced areas acquired a new relevance to modern concerns about erosion and land instability, being the agricultural land mostly threatened by abandonment or intensification and specialization of agriculture, resulting in more landslide-prone bench terraces, or heavy land levelling with increased erosion. The second case study discusses about the role of agricultural and forest roads on surface erosion and landslides. The third case study investigates geomorphic processes in an open pit mine. In all case studies, HRT served as the basis for the development of new methodologies able to recognize and analyze changes on Earth surface processes along hillslopes. The results show how anthropogenic elements have crucial effects on sediment production and sediment delivery, also influencing the landscape connectivity. The availability of HRT can improve our ability to actually model anthropogenic morphologies, quantify them, and analyse the links between anthropogenic elements and geomorphic processes. The results presented here, and the creation and dissemination of

Altered Connexin 43 and Connexin 45 protein expression in the heart as a function of social and environmental stress in the prairie vole.

Science.gov (United States)

Grippo, Angela J; Moffitt, Julia A; Henry, Matthew K; Firkins, Rachel; Senkler, Jonathan; McNeal, Neal; Wardwell, Joshua; Scotti, Melissa-Ann L; Dotson, Ashley; Schultz, Rachel

2015-01-01

Exposure to social and environmental stressors may influence behavior as well as autonomic and cardiovascular regulation, potentially leading to depressive disorders and cardiac dysfunction including elevated sympathetic drive, reduced parasympathetic function, and ventricular arrhythmias. The cellular mechanisms that underlie these interactions are not well understood. One mechanism may involve alterations in the expression of Connexin43 (Cx43) and Connexin45 (Cx45), gap junction proteins in the heart that play an important role in ensuring efficient cell-to-cell coupling and the maintenance of cardiac rhythmicity. The present study investigated the hypothesis that long-term social isolation, combined with mild environmental stressors, would produce both depressive behaviors and altered Cx43 and Cx45 expression in the left ventricle of prairie voles - a socially monogamous rodent model. Adult, female prairie voles were exposed to either social isolation (n = 22) or control (paired, n = 23) conditions (4 weeks), alone or in combination with chronic mild stress (CMS) (1 week). Social isolation, versus paired control conditions, produced significantly (p Social isolation (alone) reduced (p social and environmental stress in the prairie vole.

Potential climatic effects of anthropogenic aerosols

International Nuclear Information System (INIS)

Pueschel, R.F.

1993-01-01

Aerosols act as part of the climate system through their influence on solar and terrestrial radiation. The effect of anthropogenic aerosols on the reduction of visibility is explored in this chapter. Elemental carbon has been identified as the most effective visibility-reducing species. Most of the visibility reduction is due to particles with diameter smaller than 2.5 μm. Studies indicate that sulfate is also a very important aerosol species that results in low visibility and high turbidity. Radiative properties such as aerosol single-scattering albedo values and absorption-to-backscatter ratios purported to produce warming or cooling effects of aerosols are discussed. It is concluded that aerosol clouds have a tendency to cool when they are over a low-albedo surface and have a tendency to warm when they are over high-albedo surfaces such as snow. Anthropogenic aerosols have a tendency to warm the earth's atmospheric system, based on calculations and assumed aerosol optical properties. However, this effect is somewhat offset by the absorption and re-emission into space of infrared terrestrial radiation. The net effect depends on the ratio of the absorption coefficients in the visible and infrared and also on the surface albedo. The effects on infrared radiation are documented for two anthropogenic aerosol sources in the United States, the Denver metropolitan area and power plant plumes in New Mexico, through calculations and measurements. Measured cooling rates within an aerosol plume are not sufficient to offset the warming rate due to absorption of short-wave radiation. Research indicates that anthropogenic aerosols can possibly cause local-scale warming of the atmosphere, but global-scale climatic effects remain an open question

Future Land-Use Changes and the Potential for Novelty in Ecosystems of the United States

Science.gov (United States)

Sebastian Martinuzzi; Gregorio I. Gavier-Pizarro; Ariel E. Lugo; Volker C. Radeloff

2015-01-01

Rapid global changes due to changing land use, climate, and non-native species are altering environmental conditions, resulting in more novel communities with unprecedented species combinations. Understanding how future anthropogenic changes may affect novelty in ecosystems is important to advance environmental management and ecological research in the Anthropocene....

Histopathological alterations observed in the liver of Poecilia vivipara (Cyprinodontiformes: Poeciliidae as a tool for the environmental quality assessment of the Cachoeira River, BA

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DV Paulo

Full Text Available Histopathological alterations in liver have been widely used as a tool in studies for monitoring environmental quality. To evaluate the environmental quality in the Cachoeira river, five spots were monitored between the municipal districts of Itapé and Ilhéus, using liver histological analysis. The species chosen for analysis was Poecilia vivipara due to the fact that it is one of the most abundant in the sampling. The routine technique of inclusion and impregnation in paraffin was used, and the cuts were stained with Hematoxylin and Eosin (H & E. Histopathological alterations in the liver were evaluated semi-quantitatively and based on the severity of the lesions. The results of the histopathological alteration frequency together with the average taken from the Histopathological Alteration Index from points 1 (Vila de Itapé and 2 (Fazenda Santa Amélia showed that in this area the environment is more threatened because of some stressor agent, possibly contaminants that seem to be acting in the environment and endangering the health of fish. The statistic results demonstrated that there were no significant differences among points 1, 2 and 4, which means they are very similar to one another, and are ecologically endangered.

High-Resolution Mapping of Anthropogenic Heat in China from 1992 to 2010

Directory of Open Access Journals (Sweden)

Wangming Yang

2014-04-01

Full Text Available Anthropogenic heat generated by human activity contributes to urban and regional climate warming. Due to the resolution and accuracy of existing anthropogenic heat data, it is difficult to analyze and simulate the corresponding effects. This study exploited a new method to estimate high spatial and temporal resolutions of anthropogenic heat based on long-term data of energy consumption and the US Air Force Defense Meteorological Satellite Program-Operational Linescan System (DMSP-OLS data from 1992 to 2010 across China. Our results showed that, throughout the entire study period, there are apparent increasing trends in anthropogenic heat in three major metropoli, i.e., the Beijing-Tianjin region, the Yangzi River delta and the Pearl River delta. The annual mean anthropogenic heat fluxes for Beijing, Shanghai and Guangzhou in 2010 were 17 Wm−2, 19 and 7.8 Wm−2, respectively. Comparisons with previous studies indicate that DMSP-OLS data could provide a better spatial proxy for estimating anthropogenic heat than population density and our analysis shows better performance at large scales for estimation of anthropogenic heat.

Environmentally relevant concentrations of di(2-ethylhexyl)phthalate exposure alter larval growth and locomotion in medaka fish via multiple pathways.

Science.gov (United States)

Yang, Wen-Kai; Chiang, Li-Fen; Tan, Shi-Wei; Chen, Pei-Jen

2018-06-01

Di(2-ethylhexyl)phthalate (DEHP) is a commonly used plasticizer, with evidence of ubiquitous human exposure and widespread occurrence in the aquatic environment. It is an emerging environmental pollutant with regulatory priority; however, most studies have focused on the toxicity of DEHP related to endocrine disruption and reproduction in mammals. The ecotoxicological impact of phthalates (e.g., DEHP) on early life stages of fish under environmentally relevant concentrations of chronic exposure remains unclear. In this study, 7-day post-hatching fry of medaka fish (Oryzias latipes) underwent 21-day continuous exposure to DEHP solutions at 20, 100 and 200 μg/L to assess the effects on fish development and locomotion and related toxic mechanisms. Larval mortality was low with DEHP (20-200 μg/L) within 21 days, but such exposure significantly reduced fish body weight and length and altered swimming behavior. At 21 days, DEHP exposure resulted in specific patterns of larval locomotion (e.g., increased maximum velocity and absolute turn angle) and dose-dependently increased the mRNA expression of acetylcholinesterase (ache) but did not alter AChE activity. Transcriptional expression of antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase and peroxisome proliferation-activated receptor and retinoid X receptor genes was significantly suppressed with 21-day DEHP exposure (20-200 μg/L), with marginal alteration in reactive oxygen species levels and antioxidant activities within the dosing period. As well, DEHP altered the mRNA expression of p53-regulated apoptosis pathways, such as upregulated p53, p21 and bcl-2 and downregulated caspase-3 expression, with increased enzymatic activity of caspase-3 in larvae. Our results suggest that toxic mechanisms of waterborne DEHP altered fish growth and locomotion likely via a combined effect of oxidative stress, neurotoxicity and apoptosis pathways. Copyright © 2018

Dental health state of children living in different anthropogenic condition

Directory of Open Access Journals (Sweden)

M. A. Luchynskyі

2015-11-01

I. Y. Horbachevskyy Ternopil State Medical University of Ministry of Health of Ukraine, Ukraine, Ternopil (Ternopil, Maydan Voli, 1, 46001   Abstract   The purpose of the work is to study dental health of children living in conditions of combined negative impact of natural and technological factors. Materials and methods. It was performed an epidemiological dental examination of 2,551 children aged 6 to 15 years, who settled in different regions of the Precarpathians, in conditions of iodine and fluoride deficiency (plain - 1087 children, foothills - 730 and mountain - 734 children. Results. Comprehensive epidemiological studies found low levels of dental health of children living in different geochemical and anthropogenic conditions of Ivano-Frankivsk region (48,83 ± 0,36% in the general observation, that is not statistically different by regions examination, moreover girls level is lower, than that of boys in examined regions (48,14 ± 0,50 and (49,51 ± 0,52%, respectively. It was founded, that the main diseases, which contribute to the reduction of dental health in children, is dental caries and its complications and abnormalities of dentoalveolar system. It was found, that the frequency and severity of dentoalveolar abnormalities depend on anthropogenic environmental conditions: in children of plain and foothill regions, that suffer from greater anthropogenic pressure, dentoalveolar abnormalities where found in (67,99 ± 1,42 and (65,21 ± 1,76%, against (45,91 ± 1,84% in children of conditionally pure mountain region. These same children also often recorded more severe pathology – combined anomalies (24,09 ± 1,57 and (22,06 ± 1,90%, against (12,17 ± 1,78%, respectively. It was found the connection between the dentoalveolar abnormalities and the presence of caries (r = + 0,95; p <0,01 and periodontal tissue diseases (r = + 0,79; p <0,05.   Keywords: children, dental health, dentoalveolar abnormalities, dental caries, periodontal disease, hypoplasia.

An indicator for effects of organic toxicants on lotic invertebrate communities: Independence of confounding environmental factors over an extensive river continuum

International Nuclear Information System (INIS)

Beketov, Mikhail A.; Liess, Matthias

2008-01-01

Distinguishing between effects of natural and anthropogenic environmental factors on ecosystems is a fundamental problem in environmental science. In river systems the longitudinal gradient of environmental factors is one of the most relevant sources of dissimilarity between communities that could be confounded with anthropogenic disturbances. To test the hypothesis that in macroinvertebrate communities the distribution of species' sensitivity to organic toxicants is independent of natural longitudinal factors, but depends on contamination with organic toxicants, we analysed the relationship between community sensitivity SPEAR organic (average community sensitivity to organic toxicants) and natural and anthropogenic environmental factors in a large-scale river system, from alpine streams to a lowland river. The results show that SPEAR organic is largely independent of natural longitudinal factors, but strongly dependent on contamination with organic toxicants (petrochemicals and synthetic surfactants). Usage of SPEAR organic as a stressor-specific longitude-independent measure will facilitate detection of community disturbance by organic toxicants. - Indicator for organic toxicants at community level can be independent of natural environmental factors

Environmental pollution

International Nuclear Information System (INIS)

Odzuck, W.

1982-01-01

The volume of the anthropogenic pollution of the environment (incl. radioactivity) is of great economical importance and has also a meaning to the health and happiness of people. The pocket book introduces into the whole problem by giving exact information and data. After a general survey, the pollutions of urban-industrial, and aquatic ecosystems are dealt with. The book closes with indications as to general principles, specific dangers, and the fature development of the environmental pollution. (orig.) [de

Characterizing aquifer hydrogeology and anthropogenic chemical influences on groundwater near the Idaho Chemical Processing Plant, Idaho National Engineering Laboratory, Idaho

International Nuclear Information System (INIS)

Fromm, J.M.

1995-01-01

A conceptual model of the Eastern Snake River Plain aquifer in the vicinity of monitoring well USGS-44, downgradient of the Idaho Chemical Processing Plant (ICPP) on the Idaho National Engineering Laboratory (INEL), was developed by synthesis and comparison of previous work (40 years) and new investigations into local natural hydrogeological conditions and anthropogenic influences. Quantitative tests of the model, and other recommendations are suggested. The ICPP recovered fissionable uranium from spent nuclear fuel rods and disposed of waste fluids by release to the regional aquifer and lithosphere. Environmental impacts were assessed by a monitoring well network. The conceptual model identifies multiple, highly variable, interacting, and transient components, including INEL facilities multiple operations and liquid waste handling, systems; the anisotropic, in homogeneous aquifer; the network of monitoring and production wells, and the intermittent flow of the Big Lost River. Pre anthropogenic natural conditions and early records of anthropogenic activities were sparsely or unreliably documented making reconstruction of natural conditions or early hydrologic impacts impossible or very broad characterizations

Anthropogenic radionuclides in the marine environment: Case studies

International Nuclear Information System (INIS)

Carpenter, R.

1997-01-01

This chapter discusses three case studies of greatly different types of discharges of anthropogenic radionuclides to the marine environment. The SNAP 9A satellite burnup dispersed almost pure 238 Pu into the atmosphere over the Mozambique channel at about 25 deg. S latitude in 1964. A much more heterogeneous mixture of liquids and solids containing a variety of radionuclides of low activity levels were packaged in steel drums and sunk to the sea floor near the Farallon Islands off San Francisco, California, USA between 1994 and 1964. An extensive series of tests of nuclear and thermonuclear devices with a total yield of many megatons was conducted by the U.S. at the remote coral atolls of the Marshall Islands at 110 deg. N and 160-165 deg. E, making them the most radioactively contaminated parts of the marine environment. The chapter briefly summarizes each of these cases, and stresses the major points learned about radionuclide cycling and about environmental processes from each of them. (author)

Towards better monitoring of technology critical elements in Europe: Coupling of natural and anthropogenic cycles.

Science.gov (United States)

Nuss, Philip; Blengini, Gian Andrea

2018-02-01

The characterization of elemental cycles has a rich history in biogeochemistry. Well known examples include the global carbon cycle, or the cycles of the 'grand nutrients' nitrogen, phosphorus, and sulfur. More recently, efforts have increased to better understand the natural cycling of technology critical elements (TCEs), i.e. elements with a high supply risk and economic importance in the EU. On the other hand, tools such as material-flow analysis (MFA) can help to understand how substances and goods are transported and accumulated in man-made technological systems ('anthroposphere'). However, to date both biogeochemical cycles and MFA studies suffer from narrow system boundaries, failing to fully illustrate relative anthropogenic and natural flow magnitude and the degree to which human activity has perturbed the natural cycling of elements. We discuss important interconnections between natural and anthropogenic cycles and relevant EU raw material dossiers. Increased integration of both cycles could help to better capture the transport and fate of elements in nature including their environmental/human health impacts, highlight potential future material stocks in the anthroposphere (in-use stocks) and in nature (e.g., in soils, tailings, or mining wastes), and estimate anticipated emissions of TCEs to nature in the future (based on dynamic stock modeling). A preliminary assessment of natural versus anthropogenic element fluxes indicates that anthropogenic fluxes induced by the EU-28 of palladium, platinum, and antimony (as a result of materials uses) might be greater than the respective global natural fluxes. Increased combination of MFA and natural cycle data at EU level could help to derive more complete material cycles and initiate a discussion between the research communities of biogeochemists and material flow analysts to more holistically address the issues of sustainable resource management. Copyright © 2017 The Authors. Published by Elsevier B.V. All

Evaluation of anthropogenic influence in probabilistic forecasting of coastal change

Science.gov (United States)

Hapke, C. J.; Wilson, K.; Adams, P. N.

2014-12-01

Prediction of large scale coastal behavior is especially challenging in areas of pervasive human activity. Many coastal zones on the Gulf and Atlantic coasts are moderately to highly modified through the use of soft sediment and hard stabilization techniques. These practices have the potential to alter sediment transport and availability, as well as reshape the beach profile, ultimately transforming the natural evolution of the coastal system. We present the results of a series of probabilistic models, designed to predict the observed geomorphic response to high wave events at Fire Island, New York. The island comprises a variety of land use types, including inhabited communities with modified beaches, where beach nourishment and artificial dune construction (scraping) occur, unmodified zones, and protected national seashore. This variation in land use presents an opportunity for comparison of model accuracy across highly modified and rarely modified stretches of coastline. Eight models with basic and expanded structures were developed, resulting in sixteen models, informed with observational data from Fire Island. The basic model type does not include anthropogenic modification. The expanded model includes records of nourishment and scraping, designed to quantify the improved accuracy when anthropogenic activity is represented. Modification was included as frequency of occurrence divided by the time since the most recent event, to distinguish between recent and historic events. All but one model reported improved predictive accuracy from the basic to expanded form. The addition of nourishment and scraping parameters resulted in a maximum reduction in predictive error of 36%. The seven improved models reported an average 23% reduction in error. These results indicate that it is advantageous to incorporate the human forcing into a coastal hazards probability model framework.

Detecting anthropogenic climate change with an optimal fingerprint method

International Nuclear Information System (INIS)

Hegerl, G.C.; Storch, H. von; Hasselmann, K.; Santer, B.D.; Jones, P.D.

1994-01-01

We propose a general fingerprint strategy to detect anthropogenic climate change and present application to near surface temperature trends. An expected time-space-variable pattern of anthropogenic climate change (the 'signal') is identified through application of an appropriate optimally matched space-time filter (the 'fingerprint') to the observations. The signal and the fingerprint are represented in a space with sufficient observed and simulated data. The signal pattern is derived from a model-generated prediction of anthropogenic climate change. Application of the fingerprint filter to the data yields a scalar detection variable. The statistically optimal fingerprint is obtained by weighting the model-predicted pattern towards low-noise directions. A combination of model output and observations is used to estimate the noise characteristics of the detection variable, arising from the natural variability of climate in the absence of external forcing. We test then the null hypothesis that the observed climate change is part of natural climate variability. We conclude that a statistically significant externally induced warming has been observed, with the caveat of a possibly inadequate estimate of the internal climate variability. In order to attribute this warming uniquely to anthropogenic greenhouse gas forcing, more information on the climate's response to other forcing mechanisms (e.g. changes in solar radiation, volcanic or anthropogenic aerosols) and their interaction is needed. (orig./KW)

Climatología urbana por modificación antropogénica. Alteración del balance de energía natural / Urban climatology by anthropogenic modification. Alteration of the natural energy balance

Directory of Open Access Journals (Sweden)

Fuentes Pérez, Carlos Alberto

2015-09-01

Full Text Available La investigación valora el análisis climático histórico para establecer la temperatura y humedad relativa media, en contraste con la climatología urbana por modificación antropogénica estudio de caso, y su contribución de consigna fijado para invierno y verano que son las estaciones críticas. El procedimiento metodológico a implementar, apoya a los planificadores urbanos a no tener que participar científicamente para evaluar el emplazamiento térmico de sus proyectos y por lo tanto se puede acelerar el proceso de diseño sin comprometer el énfasis en el contexto urbano sustentable. Con base a los resultados se establecen las islas de calor urbano y su huella térmica en el hábitat. El objetivo de la presente investigación es determinar la climatología urbana por modificación antropogénica y su alteración a la calidad del hábitat en Tampico, México. The research assesses the historical climate analysis to determine the average temperature and relative humidity, in contrast to urban anthropogenic weather modification case study, and their contribution setpoint set for winter and summer are the season’s criticism. The methodology to implement, procedure supports urban planners will not have to participate to scientifically evaluate the thermal construction projects and therefore can accelerate the design process without compromising the emphasis on sustainable urban context. Based on the results of urban heat islands and thermal footprint habitat established. The objective of this research is to determine the urban climate by anthropogenic modification and alteration of habitat quality in Tampico, Mexico.

Small-scale opencast mining: an important research field for anthropogenic geomorphology

Directory of Open Access Journals (Sweden)

Byizigiro, R. Vaillant

2015-12-01

Full Text Available Artisanal and small-scale mining (A&SM is a growing economic sector in many third-world countries. This review focuses on anthropo-geomorphic factors and processes associated with small-scale opencast mining (SSOM, a form of A&SM in which near-surface ores are extracted by removing relatively thin covers of soil, bedrock or sediments. Being widespread and commonly conducted without proper planning and beyond the control of local authorities, this form of mining has potentially large impacts on landforms and landscape dynamics, often resulting in drastic consequences for the local environment and agriculture. SSOM should be regarded as a component of anthropogenic geomorphology because it involves the role of humans in creating landforms and modifying the operation of natural geomorphological processes, such as weathering, erosion, transport and deposition. By initiating new and modifying natural geomorphic processes, SSOM causes and/or accelerates geomorphic processes, resulting in various forms of land degradation. While the direct geomorphic impact of SSOM is in general easily discernible and leads to characteristic features, such as excavated pits and overburden spoil heaps, many secondary impacts are attributed to geomorphic processes triggered in the wake of the primary mining-induced landscape alterations. The magnitude of such secondary implications may well extend beyond the actual mining areas, but these effects have not been thoroughly addressed in the research so far. This review summarizes the known studies on the geomorphic impacts of SSOM operations and highlights common geomorphic processes and landforms associated with this type of anthropogenic activity, thus establishing a starting point for further in-depth research.

Anthropogenic radiofrequency electromagnetic fields as an emerging threat to wildlife orientation.

Science.gov (United States)

Balmori, Alfonso

2015-06-15

The rate of scientific activity regarding the effects of anthropogenic electromagnetic radiation in the radiofrequency (RF) range on animals and plants has been small despite the fact that this topic is relevant to the fields of experimental biology, ecology and conservation due to its remarkable expansion over the past 20 years. Current evidence indicates that exposure at levels that are found in the environment (in urban areas and near base stations) may particularly alter the receptor organs to orient in the magnetic field of the earth. These results could have important implications for migratory birds and insects, especially in urban areas, but could also apply to birds and insects in natural and protected areas where there are powerful base station emitters of radiofrequencies. Therefore, more research on the effects of electromagnetic radiation in nature is needed to investigate this emerging threat. Copyright © 2015 Elsevier B.V. All rights reserved.

Opportunities of education in of environmental law in the form of e-learning

International Nuclear Information System (INIS)

Jurik, L.

2005-01-01

The environmental laws were originated as a result of endeavour about solving of unfavourable anthropogenic influences on the environment. In this presentation author presents system of e-learning of environmental laws. Historical aspects and principles of e-learning are discussed

δ15N as a proxy for historic anthropogenic nitrogen loading in Charleston Harbor, SC, USA

Science.gov (United States)

Payne, T. N.; Andrus, C. F. T.

2015-12-01

Bivalve shell geochemistry can serve as a useful indicator of changes in coastal environments. There is increasing interest in developing paleoenvironmental proxies from mollusk shell organic components. Numerous studies have focused on how the δ15N obtained from bivalve tissues can be used to trace present-day wastewater input into estuaries. However, comparatively little attention has been paid to tracing the impact of anthropogenic nitrogen loading into estuaries over time. By measuring historic levels of δ15N in the organic fraction of oyster shells (Crassostrea virginica) from archaeological sites around Charleston Harbor and comparing those levels to the δ15N content of modern shells, it is possible to assess how nitrogen has fluctuated historically in the area. Whole-shell samples from the Late Archaic Period (~3000-4000 BP, Late Woodland Period (~1400-800 BP), 18th and 19th centuries, and modern controls were measured for %N and d15N. Evidence of increased anthropogenic input of N is expected to begin in the early historic period based on similar analysis in Chesapeake Bay. More ancient samples may give insight into baseline conditions prior to recent population growth and industrialization. This information could help understand how large-scale anthropogenic nitrogen loading has affected coastal ecosystems over time and guide future remediation. Furthermore, this project will help refine and improve this novel proxy of past environmental conditions.

Measuring Hair Cortisol Concentrations to Assess the Effect of Anthropogenic Impacts on Wild Chimpanzees (Pan troglodytes).

Science.gov (United States)

Carlitz, Esther H D; Miller, Robert; Kirschbaum, Clemens; Gao, Wei; Hänni, Daniel C; van Schaik, Carel P

2016-01-01

Non-human primates face major environmental changes due to increased human impacts all over the world. Although some species are able to survive in certain landscapes with anthropogenic impact, their long-term viability and fitness may be decreased due to chronic stress. Here we assessed long-term stress levels through cortisol analysis in chimpanzee hair obtained from sleeping nests in northwestern Uganda, in order to estimate welfare in the context of ecotourism, forest fragmentation with human-wildlife conflicts, and illegal logging with hunting activity (albeit not of primates), compared with a control without human contact or conflict. Concerning methodological issues, season [F(2,129) = 37.4, p < 0.0001, r2 = 0.18] and the age of nests [F(2,178) = 20.3, p < 0.0001, r2 = 0.11] significantly predicted hair cortisol concentrations (HCC). With regard to effects of anthropogenic impacts, our results neither showed elevation of HCC due to ecotourism, nor due to illegal logging compared to their control groups. We did, however, find significantly increased HCC in the fragment group compared to chimpanzees living in a nearby intact forest [F(1,88) = 5.0, p = 0.03, r2 = 0.20]. In conclusion, our results suggest that hair cortisol analysis is a powerful tool that can help understanding the impact of anthropogenic disturbances on chimpanzee well-being and could be applied to other great ape species.

Natural and anthropogenic sources of chemical elements in sediment profiles from the Admiralty Bay, Antarctica

International Nuclear Information System (INIS)

Ribeiro, A.P.; Figueira, R.C.L.; Silva, C.R.A.; Franca, E.J.; Mahiques, M.M.; Bicego, M.C.; Montone, R.C.

2010-01-01

Full text: The Antarctic Continent and its surrounding Southern Ocean are the least known regions of the world, mainly due to the most unfavorable climatic conditions, in which sampling for environmental studies are quite difficult to be carried out. Admiralty Bay on the King George Island (Antarctica) hosts three research stations, Arctowski, Ferraz and Macchu Picchu, which are operate by Poland, Brazil and Peru, respectively. Therefore, human activities in this region require the use of fossil fuel as an energy source, which is also considered the main source of pollutants in the area. This work investigated the natural and anthropogenic inputs of chemical elements in sediment samples collected close to Ferraz Station, during the 25 th Brazilian Antarctica Expedition in the 2006/2007 austral summer. Total concentrations of As, Zn and Sc were determined in sediment profiles by using the Instrumental Neutron Activation Analysis (INAA). The analytical technique employed to determine the major elements such as Fe, Al, Ca, Mn and Ti was X-ray fluorescence (XRF) spectroscopy. For estimating the sedimentation rate, High Resolution Gamma Ray Spectrometry was applied to determine 137 Cs, after 30 days, to achieve secular equilibrium. According to the enrichment factor and the geochronology analysis, the most relevant enrichment was observed for As in the sediment samples, suggesting the increasing of its content due to the Brazilian activities in the Admiralty Bay. Despite some evidences of anthropogenic contribution, the study indicated low level of environmental risk for this region. (author)

Cascading impacts of anthropogenically driven habitat loss: deforestation, flooding, and possible lead poisoning in howler monkeys (Alouatta pigra).

Science.gov (United States)

Serio-Silva, Juan Carlos; Olguín, Eugenia J; Garcia-Feria, Luis; Tapia-Fierro, Karla; Chapman, Colin A

2015-01-01

To construct informed conservation plans, researchers must go beyond understanding readily apparent threats such as habitat loss and bush-meat hunting. They must predict subtle and cascading effects of anthropogenic environmental modifications. This study considered a potential cascading effect of deforestation on the howler monkeys (Alouatta pigra) of Balancán, Mexico. Deforestation intensifies flooding. Thus, we predicted that increased flooding of the Usumacinta River, which creates large bodies of water that slowly evaporate, would produce increased lead content in the soils and plants, resulting in lead exposure in the howler monkeys. The average lead levels were 18.18 ± 6.76 ppm in the soils and 5.85 ± 4.37 ppm in the plants. However, the average lead content of the hair of 13 captured howler monkeys was 24.12 ± 5.84 ppm. The lead levels in the animals were correlated with 2 of 15 blood traits (lactate dehydrogenase and total bilirubin) previously documented to be associated with exposure to lead. Our research illustrates the urgent need to set reference values indicating when adverse impacts of high environmental lead levels occur, whether anthropogenic or natural, and the need to evaluate possible cascading effects of deforestation on primates.

Fluvial gravel stabilization by net-spinning Hydropsychid caddisflies: exploring the magnitude and geographic scope of ecosystem engineering effect and evaluating resistance to anthropogenic stresses

Science.gov (United States)

Daniels, M.; Albertson, L.; Sklar, L. S.; Tumolo, B.; Mclaughlin, M. K.

2017-12-01

Several studies have demonstrated the substantial effects that organisms can have on earth surface processes. Known as ecosystem engineers, in streams these organisms maintain, modify, or create physical habitat structure by influencing fluvial processes such as gravel movement, fine sediment deposition and bank erosion. However, the ecology of ecosystem engineers and the magnitude of ecosystem engineering effects in a world increasingly influence by anthropogenically-driven changes is not well understood. Here we present a synthesis of research findings on the potential gravel stabilization effects of Hydropsychid caddisflies, a globally distributed group of net-spinning insects that live in the benthic substrate of most freshwater streams. Hydropsychid caddisflies act as ecosystem engineers because these silk structures can fundamentally alter sediment transport conditions, including sediment stability and flow currents. The silk nets spun by these insects attach gravel grains to one another, increasing the shear stress required to initiate grain entrainment. In a series of independent laboratory experiments, we investigate the gravel size fractions most affected by these silk attachments. We also investigate the role of anthropogenic environmental stresses on ecosystem engineering potential by assessing the impact of two common stressors, high fine sediment loads and stream drying, on silk structures. Finally, an extensive field survey of grain size and Hydropsychid caddisfly population densities informs a watershed-scale network model of Hydropsychid caddisfly gravel stabilizing potential. Our findings provide some of the first evidence that caddisfly silk may be a biological structure that is resilient to various forms of human-mediated stress and that the effects of animal ecosystem engineers are underappreciated as an agent of resistance and recovery for aquatic communities experiencing changes in sediment loads and hydrologic regimes.

Anthropogenic organic micro-pollutants and pathogens in the urban water cycle: assessment, barriers and risk communication (ASKURIS)

OpenAIRE

Jekel, Martin; Ruhl, Aki Sebastian; Meinel, Felix; Zietzschmann, Frederik; Pflugmacher Lima, Stephan; Baur, Nina; Wenzel, Melanie; Gnierß, Regina; Sperlich, Alexander; Dünnbier, Uwe; Böckelmann, Uta; Hummelt, Daniel; van Baar, Patricia; Wode, Florian; Petersohn, Dietmar

2013-01-01

First published by Springer: Jekel, Martin et al.: Anthropogenic organic micro-pollutants and pathogens in the urban water cycle: assessment, barriers and risk communication (ASKURIS). - In: Environmental Sciences Europe. - ISSN 2190-4715 (online). - 25 (2013), art. 20. - doi:10.1186/2190-4715-25-20. In urban areas, water often flows along a partially closed water cycle in which treated municipal wastewater is discharged into surface waters which are one source of raw waters used for dr...

Assessing the observed impact of anthropogenic climate change

OpenAIRE

Hansen, G; Stone, D

2016-01-01

© 2016 Macmillan Publishers Limited. All rights reserved. Impacts of recent regional changes in climate on natural and human systems are documented across the globe, yet studies explicitly linking these observations to anthropogenic forcing of the climate are scarce. Here we provide a systematic assessment of the role of anthropogenic climate change for the range of impacts of regional climate trends reported in the IPCC's Fifth Assessment Report. We find that almost two-thirds of the impacts...

Influence of anthropogenic transformation of Danube–Dniester interfluve on natural foci of tularaemia

Directory of Open Access Journals (Sweden)

I. T. Rusev

2011-04-01

Full Text Available The paper is devoted to the problem of occurrence of bacteria Francisella tularensis in steppe coastal zone of the Black Sea west part in the second half of XX century. The key factor decreasing the activity of tularaemia natural foci is anthropogenic influence. Resumed activity of natural foci appeared after implementation of big irrigation and drainage construction in former USSR – building of the Danube-Dniester-Dnepr irrigation system resulted in forming new environmental conditions as well as corridors for tularaemia distribution. The practical recommendation is to implement the eco-epizootological monitoring and to collect data for developing practical management of the natural foci of disease.

Anthropogenic radionuclides in the environment

Energy Technology Data Exchange (ETDEWEB)

Hu, Q; Weng, J; Wang, J

2007-11-15

Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview of anthropogenic radionuclide contamination in the environment, as well as the salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current development that contribute to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) commercial fuel reprocessing; (5) geological repository of high-level nuclear wastes, and (6) nuclear accidents. Then, we summarize the geochemical behavior for radionuclides {sup 99}Tc, {sup 129}I, and {sup 237}Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment. Biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

Key ecological responses to nitrogen are altered by climate change

Science.gov (United States)

Greaver, T.L.; Clark, C.M.; Compton, J.E.; Vallano, D.; Talhelm, A. F.; Weaver, C.P.; Band, L.E.; Baron, Jill S.; Davidson, E.A.; Tague, C.L.; Felker-Quinn, E.; Lynch, J.A.; Herrick, J.D.; Liu, L.; Goodale, C.L.; Novak, K. J.; Haeuber, R. A.

2016-01-01

Climate change and anthropogenic nitrogen deposition are both important ecological threats. Evaluating their cumulative effects provides a more holistic view of ecosystem vulnerability to human activities, which would better inform policy decisions aimed to protect the sustainability of ecosystems. Our knowledge of the cumulative effects of these stressors is growing, but we lack an integrated understanding. In this Review, we describe how climate change alters key processes in terrestrial and freshwater ecosystems related to nitrogen cycling and availability, and the response of ecosystems to nitrogen addition in terms of carbon cycling, acidification and biodiversity.

Issues and options in addressing the environmental consequences of the livestock sector's growth

NARCIS (Netherlands)

Gerber, P.J.; Vellinga, Th.V.; Steinfeld, H.

2010-01-01

The growth of the livestock sector is being achieved at substantial environmental costs. Today, livestock are a major stressor of the global environmental, occupying a quarter of emerged land (including a third of arable land), contributing close to a fifth of the anthropogenic greenhouse gas

Environmental considerations influencing dietary choices: exploring consumer attitudes

Science.gov (United States)

Introduction: With increasing focus on anthropogenic causes of climate change, more attention is on the contribution of food systems. Public discourse on sustainability leads consumers to consider how they may reduce environmental damage with personal dietary decisions. US-based studies evaluating p...

What is the impact on fish recruitment of anthropogenic physical and structural habitat change in shallow nearshore areas in temperate systems? A systematic review protocol

DEFF Research Database (Denmark)

MacUra, B.; Lönnstedt, O.M.; Byström, P.

2016-01-01

and spawning habitats of many fish and other aquatic species. Several coastal fish populations have seen marked declines in abundance and diversity during the past two decades. A systematic review on the topic would clarify if anthropogenic physical and structural changes of near-shore areas have effects...... on fish recruitment and which these effects are. Methods: The review will examine how various physical and structural anthropogenic changes of nearshore fish habitats affect fish recruitment. Relevant studies include small- and large-scale field studies in marine and brackish systems or large lakes......Background: Shallow nearshore marine ecosystems are changing at an increasing rate due to a range of human activities such as urbanisation and commercial development. The growing numbers of constructions and other physical and structural alterations of the shoreline often take place in nursery...

Anthropogenic Radionuglides in Marine Polar Regions

Science.gov (United States)

Holm, Elis

The polar regions are important for the understanding of long range water and atmospheric transport of anthropogenic substances. Investigations show that atmospheric transport of anthropogenic radionuclides is the most important route of transport to the Antarctic while water transport plays a greater role for the Arctic. Fallout from nuclear detonation tests is the major source in the Antarctic while in the Arctic other sources, especially European reprocessing facilities, dominate for conservatively behaving rdionuclides such as 137Cs . The flux of 137Cs and 239+240Pu in the Antarctic is about 1/10 of that for the Arctic and the resulting concentrations in surface sea-water show the same ratio for the two areas. In the Antarctic concentration factors for 137Cs are higher than in the Arctic for similar species

Anthropogenics: human influence on global and genetic homogenization of parasite populations.

Science.gov (United States)

Zarlenga, Dante S; Hoberg, Eric; Rosenthal, Benjamin; Mattiucci, Simonetta; Nascetti, Giuseppe

2014-12-01

The distribution, abundance, and diversity of life on Earth have been greatly shaped by human activities. This includes the geographic expansion of parasites; however, measuring the extent to which humans have influenced the dissemination and population structure of parasites has been challenging. In-depth comparisons among parasite populations extending to landscape-level processes affecting disease emergence have remained elusive. New research methods have enhanced our capacity to discern human impact, where the tools of population genetics and molecular epidemiology have begun to shed light on our historical and ongoing influence. Only since the 1990s have parasitologists coupled morphological diagnosis, long considered the basis of surveillance and biodiversity studies, with state-of-the-art tools enabling variation to be examined among, and within, parasite populations. Prior to this time, populations were characterized only by phenotypic attributes such as virulence, infectivity, host range, and geographical location. The advent of genetic/molecular methodologies (multilocus allozyme electrophoresis, polymerase chain reaction-DNA [PCR-DNA] fragments analysis, DNA sequencing, DNA microsatellites, single nucleotide polymorphisms, etc.) have transformed our abilities to reveal variation among, and within, populations at local, regional, landscape, and global scales, and thereby enhanced our understanding of the biosphere. Numerous factors can affect population structure among parasites, e.g., evolutionary and ecological history, mode of reproduction and transmission, host dispersal, and life-cycle complexity. Although such influences can vary considerably among parasite taxa, anthropogenic factors are demonstrably perturbing parasite fauna. Minimal genetic structure among many geographically distinct (isolated) populations is a hallmark of human activity, hastened by geographic introductions, environmental perturbation, and global warming. Accelerating

Chronic anthropogenic noise disrupts glucocorticoid signaling and has multiple effects on fitness in an avian community.

Science.gov (United States)

Kleist, Nathan J; Guralnick, Robert P; Cruz, Alexander; Lowry, Christopher A; Francis, Clinton D

2018-01-23

Anthropogenic noise is a pervasive pollutant that decreases environmental quality by disrupting a suite of behaviors vital to perception and communication. However, even within populations of noise-sensitive species, individuals still select breeding sites located within areas exposed to high noise levels, with largely unknown physiological and fitness consequences. We use a study system in the natural gas fields of northern New Mexico to test the prediction that exposure to noise causes glucocorticoid-signaling dysfunction and decreases fitness in a community of secondary cavity-nesting birds. In accordance with these predictions, and across all species, we find strong support for noise exposure decreasing baseline corticosterone in adults and nestlings and, conversely, increasing acute stressor-induced corticosterone in nestlings. We also document fitness consequences with increased noise in the form of reduced hatching success in the western bluebird ( Sialia mexicana ), the species most likely to nest in noisiest environments. Nestlings of all three species exhibited accelerated growth of both feathers and body size at intermediate noise amplitudes compared with lower or higher amplitudes. Our results are consistent with recent experimental laboratory studies and show that noise functions as a chronic, inescapable stressor. Anthropogenic noise likely impairs environmental risk perception by species relying on acoustic cues and ultimately leads to impacts on fitness. Our work, when taken together with recent efforts to document noise across the landscape, implies potential widespread, noise-induced chronic stress coupled with reduced fitness for many species reliant on acoustic cues.

Multivariate statistical and GIS-based approach to identify source of anthropogenic impacts on metallic elements in sediments from the mid Guangdong coasts, China

International Nuclear Information System (INIS)

Gu Yangguang; Wang, Zhao-Hui; Lu Songhui; Jiang Shijun; Mu Dehai; Shu Yonghong

2012-01-01

Growing concerns surround the mid Guangdong coasts, one of China’s fastest and developing economical regions. To study the environmental impacts of economic and industrial development, we measured ten metallic elements (Hg, Pb, Cu, Zn, Fe, Al, Ni, Sr, Li, and Co) in surface sediments from nineteen stations in three bays. All these metals showed concentrations substantially higher than their background values, suggesting possible anthropogenic pollution. Highest metal levels were close to the nuclear power plants likely as a result of nuclear waste discharges. Results revealed that Hg, Pb, and Sr largely originated from human activities, while Cu, Ni, Co, Al, and Fe mainly from natural rock weathering. Two types of anthropogenic sources were identified through a principal component analysis, one from shipping industry, port transport service and nuclear power plants, and the other from municipal sewage and coal power plant. - Highlights: ► Ten metallic elements in surface sediments from mid Guangdong coasts were measured. ► High metal levels occurred close to the nuclear power plants. ► Hg, Pb and Sr mainly originated from human activities. ► Two types of anthropogenic metallic sources were identified in this region. - Hot spots of metallic elements were close to the nuclear power plants. Industrial and municipal discharges were the main anthropogenic metallic source.

Reconciling anthropogenic climate change with observed temperature 1998-2008.

Science.gov (United States)

Kaufmann, Robert K; Kauppi, Heikki; Mann, Michael L; Stock, James H

2011-07-19

Given the widely noted increase in the warming effects of rising greenhouse gas concentrations, it has been unclear why global surface temperatures did not rise between 1998 and 2008. We find that this hiatus in warming coincides with a period of little increase in the sum of anthropogenic and natural forcings. Declining solar insolation as part of a normal eleven-year cycle, and a cyclical change from an El Nino to a La Nina dominate our measure of anthropogenic effects because rapid growth in short-lived sulfur emissions partially offsets rising greenhouse gas concentrations. As such, we find that recent global temperature records are consistent with the existing understanding of the relationship among global surface temperature, internal variability, and radiative forcing, which includes anthropogenic factors with well known warming and cooling effects.

Health at the Sub-catchment Scale: Typhoid and Its Environmental Determinants in Central Division, Fiji.

Science.gov (United States)

Jenkins, Aaron Peter; Jupiter, Stacy; Mueller, Ute; Jenney, Adam; Vosaki, Gandercillar; Rosa, Varanisese; Naucukidi, Alanieta; Mulholland, Kim; Strugnell, Richard; Kama, Mike; Horwitz, Pierre

2016-12-01

The impact of environmental change on transmission patterns of waterborne enteric diseases is a major public health concern. This study concerns the burden and spatial nature of enteric fever, attributable to Salmonella Typhi infection in the Central Division, Republic of Fiji at a sub-catchment scale over 30-months (2013-2015). Quantitative spatial analysis suggested relationships between environmental conditions of sub-catchments and incidence and recurrence of typhoid fever. Average incidence per inhabited sub-catchment for the Central Division was high at 205.9/100,000, with cases recurring in each calendar year in 26% of sub-catchments. Although the numbers of cases were highest within dense, urban coastal sub-catchments, the incidence was highest in low-density mountainous rural areas. Significant environmental determinants at this scale suggest increased risk of exposure where sediment yields increase following runoff. The study suggests that populations living on large systems that broaden into meandering mid-reaches and floodplains with alluvial deposition are at a greater risk compared to small populations living near small, erosional, high-energy headwaters and small streams unconnected to large hydrological networks. This study suggests that anthropogenic alteration of land cover and hydrology (particularly via fragmentation of riparian forest and connectivity between road and river networks) facilitates increased transmission of typhoid fever and that environmental transmission of typhoid fever is important in Fiji.

Measuring Hair Cortisol Concentrations to Assess the Effect of Anthropogenic Impacts on Wild Chimpanzees (Pan troglodytes.

Directory of Open Access Journals (Sweden)

Esther H D Carlitz

Full Text Available Non-human primates face major environmental changes due to increased human impacts all over the world. Although some species are able to survive in certain landscapes with anthropogenic impact, their long-term viability and fitness may be decreased due to chronic stress. Here we assessed long-term stress levels through cortisol analysis in chimpanzee hair obtained from sleeping nests in northwestern Uganda, in order to estimate welfare in the context of ecotourism, forest fragmentation with human-wildlife conflicts, and illegal logging with hunting activity (albeit not of primates, compared with a control without human contact or conflict. Concerning methodological issues, season [F(2,129 = 37.4, p < 0.0001, r2 = 0.18] and the age of nests [F(2,178 = 20.3, p < 0.0001, r2 = 0.11] significantly predicted hair cortisol concentrations (HCC. With regard to effects of anthropogenic impacts, our results neither showed elevation of HCC due to ecotourism, nor due to illegal logging compared to their control groups. We did, however, find significantly increased HCC in the fragment group compared to chimpanzees living in a nearby intact forest [F(1,88 = 5.0, p = 0.03, r2 = 0.20]. In conclusion, our results suggest that hair cortisol analysis is a powerful tool that can help understanding the impact of anthropogenic disturbances on chimpanzee well-being and could be applied to other great ape species.

Analytic Hierarchy Process for Personalising Environmental Information

Science.gov (United States)

Kabassi, Katerina

2014-01-01

This paper presents how a Geographical Information System (GIS) can be incorporated in an intelligent learning software system for environmental matters. The system is called ALGIS and incorporates the GIS in order to present effectively information about the physical and anthropogenic environment of Greece in a more interactive way. The system…

Global gridded anthropogenic emissions inventory of carbonyl sulfide

Science.gov (United States)

Zumkehr, Andrew; Hilton, Tim W.; Whelan, Mary; Smith, Steve; Kuai, Le; Worden, John; Campbell, J. Elliott

2018-06-01

Atmospheric carbonyl sulfide (COS or OCS) is the most abundant sulfur containing gas in the troposphere and is an atmospheric tracer for the carbon cycle. Gridded inventories of global anthropogenic COS are used for interpreting global COS measurements. However, previous gridded anthropogenic data are a climatological estimate based on input data that is over three decades old and are not representative of current conditions. Here we develop a new gridded data set of global anthropogenic COS sources that includes more source sectors than previously available and uses the most current emissions factors and industry activity data as input. Additionally, the inventory is provided as annually varying estimates from years 1980-2012 and employs a source specific spatial scaling procedure. We estimate a global source in year 2012 of 406 Gg S y-1 (range of 223-586 Gg S y-1), which is highly concentrated in China and is twice as large as the previous gridded inventory. Our large upward revision in the bottom-up estimate of the source is consistent with a recent top-down estimate based on air-monitoring and Antarctic firn data. Furthermore, our inventory time trends, including a decline in the 1990's and growth after the year 2000, are qualitatively consistent with trends in atmospheric data. Finally, similarities between the spatial distribution in this inventory and remote sensing data suggest that the anthropogenic source could potentially play a role in explaining a missing source in the global COS budget.

Identifying anthropogenic anomalies in air, surface and groundwater temperatures in Germany.

Science.gov (United States)

Benz, Susanne A; Bayer, Peter; Blum, Philipp

2017-04-15

Human activity directly influences ambient air, surface and groundwater temperatures. The most prominent phenomenon is the urban heat island effect, which has been investigated particularly in large and densely populated cities. This study explores the anthropogenic impact on the thermal regime not only in selected urban areas, but on a countrywide scale for mean annual temperature datasets in Germany in three different compartments: measured surface air temperature, measured groundwater temperature, and satellite-derived land surface temperature. Taking nighttime lights as an indicator of rural areas, the anthropogenic heat intensity is introduced. It is applicable to each data set and provides the difference between measured local temperature and median rural background temperature. This concept is analogous to the well-established urban heat island intensity, but applicable to each measurement point or pixel of a large, even global, study area. For all three analyzed temperature datasets, anthropogenic heat intensity grows with increasing nighttime lights and declines with increasing vegetation, whereas population density has only minor effects. While surface anthropogenic heat intensity cannot be linked to specific land cover types in the studied resolution (1km×1km) and classification system, both air and groundwater show increased heat intensities for artificial surfaces. Overall, groundwater temperature appears most vulnerable to human activity, albeit the different compartments are partially influenced through unrelated processes; unlike land surface temperature and surface air temperature, groundwater temperatures are elevated in cultivated areas as well. At the surface of Germany, the highest anthropogenic heat intensity with 4.5K is found at an open-pit lignite mine near Jülich, followed by three large cities (Munich, Düsseldorf and Nuremberg) with annual mean anthropogenic heat intensities >4K. Overall, surface anthropogenic heat intensities >0K and

Impact of anthropogenic climate change on wildfire across western US forests.

Science.gov (United States)

Abatzoglou, John T; Williams, A Park

2016-10-18

Increased forest fire activity across the western continental United States (US) in recent decades has likely been enabled by a number of factors, including the legacy of fire suppression and human settlement, natural climate variability, and human-caused climate change. We use modeled climate projections to estimate the contribution of anthropogenic climate change to observed increases in eight fuel aridity metrics and forest fire area across the western United States. Anthropogenic increases in temperature and vapor pressure deficit significantly enhanced fuel aridity across western US forests over the past several decades and, during 2000-2015, contributed to 75% more forested area experiencing high (>1 σ) fire-season fuel aridity and an average of nine additional days per year of high fire potential. Anthropogenic climate change accounted for ∼55% of observed increases in fuel aridity from 1979 to 2015 across western US forests, highlighting both anthropogenic climate change and natural climate variability as important contributors to increased wildfire potential in recent decades. We estimate that human-caused climate change contributed to an additional 4.2 million ha of forest fire area during 1984-2015, nearly doubling the forest fire area expected in its absence. Natural climate variability will continue to alternate between modulating and compounding anthropogenic increases in fuel aridity, but anthropogenic climate change has emerged as a driver of increased forest fire activity and should continue to do so while fuels are not limiting.

Environmental exposure and altered menstrual function

Energy Technology Data Exchange (ETDEWEB)

Keye, W.R. Jr.

1984-01-01

The impact of environmental agents and occupational factors on hypothalamic and pituitary function and menstruation are poorly understood. To date, most research related to environment, occupation, and reproduction has focused on pregnancy outcome, not menstrual function. It is imperative, however, that menstrual function be considered as an outcome variable in the study of reproduction and occupation.

Bio-monitoring of the most industrialized area in Poland: Trees' response to climate and anthropogenic environmental changes

Science.gov (United States)

Sensuła, Barbara; Wilczyński, Sławomir; Piotrowska, Natalia

2017-04-01

Silesia is one of the regions with the highest levels of air pollution in Europe, highly industrialized over the years and highly populated. In this study, trees (Pinus Sylvestris L.)growing in the heavily urbanized area in close proximity to point-source pollution emitters, such as a heat and power plant, nitrogen plant, and steelworks in Silesia (Poland), were analyzed as bio-indicators of contemporary environmental changes. Trees are a very good archive of ecosystem changes, becouse they are sensitive to climate changes and anthropogenic pollution. The pollution impacts human, plants and animal life and different ecosystem processes. The changes in the ecosystem can disturb the metabolism and physiological processes of trees, and consequently, they also have an effect on the wood structure, tree ring width and the isotopic composition of wood and its components. The analysed samples covered the time period of the development of industrialization and the modernization in the industrial sector in Poland. In Poland, the systematic long-term monitoring of air pollutants is generally restricted to rural point-source regions in urban areas. Even for those areas, air pollution emissions were not continually monitored and data is only available for the last decades. Tree ring series that present long-term data can be used to analyse the ecosystem changes, caused by human activities. The conifers investigated in this study have grown for many years under the stress of environmental contamination. We analysed the spatiotemporal distribution of growth reductions, the depth of reduction with respect to the distance from the emitter, the relationship between tree growth and radiocarbon and stable isotope composition and climate during the industry development period and during pro-ecological strategy application. Pines chronologies indicate that trees have a similar sensitivity to most climatic elements of the previous and given year, but there is also observed a different

Small Boreal Lake Ecosystem Evolution under the Influence of Natural and Anthropogenic Factors: Results of Multidisciplinary Long-Term Study

Directory of Open Access Journals (Sweden)

Liudmila Shirokova

2016-07-01

Full Text Available Small aquatic ecosystems of the boreal zone are known to be most sensitive indicators of on-going environmental change as well as local anthropogenic pressure, while being highly vulnerable to external impacts. Compared to rather detailed knowledge of the evolution of large and small lakes in Scandinavia and Canada, and large lakes in Eurasia, highly abundant small boreal lakes of northwest Russia have received very little attention, although they may become important centers of attraction of growing rural population in the near future. Here we present the results of a multidisciplinary, multi-annual study of a small boreal humic lake of NW Russia. A shallow (3 m and a deep (16 m site of this lake were regularly sampled for a range of chemical and biological parameters. Average multi-daily, summer-time values of the epilimnion (upper oxygenated layer of the lake provided indications of possible trends in temperature, nutrients, and bacterio-plankton concentration that revealed the local pollution impact in the shallow zone and overall environmental trend in the deep sampling point of the lake. Organic phosphorus, nitrate, and lead were found to be most efficient tracers of local anthropogenic pollution, especially visible in the surface layer of the shallow site of the lake. Cycling of trace elements between the epilimnion and hypolimnion is tightly linked to dissolved organic matter speciation and size fractionation due to the dominance of organic and organo-ferric colloids. The capacity of lake self-purification depends on the ratio of primary productivity to mineralization of organic matter. This ratio remained >1 both during winter and summer periods, which suggests a high potential of lake recovery from the input of allochthonous dissolved organic matter and local anthropogenic pollution.

Anthropogenic impacts on Costa Rican bat parasitism are sex specific.

Science.gov (United States)

Frank, Hannah K; Mendenhall, Chase D; Judson, Seth D; Daily, Gretchen C; Hadly, Elizabeth A

2016-07-01

While anthropogenic impacts on parasitism of wildlife are receiving growing attention, whether these impacts vary in a sex-specific manner remains little explored. Differences between the sexes in the effect of parasites, linked to anthropogenic activity, could lead to uneven sex ratios and higher population endangerment. We sampled 1108 individual bats in 18 different sites across an agricultural mosaic landscape in southern Costa Rica to investigate the relationships between anthropogenic impacts (deforestation and reductions in host species richness) and bat fly ectoparasitism of 35 species of Neotropical bats. Although female and male bat assemblages were similar across the deforestation gradient, bat fly assemblages tracked their hosts closely only on female bats. We found that in female hosts, parasite abundance per bat decreased with increasing bat species richness, while in male hosts, parasite abundance increased. We hypothesize the differences in the parasite-disturbance relationship are due to differences in roosting behavior between the sexes. We report a sex-specific parasite-disturbance relationship and argue that sex differences in anthropogenic impacts on wildlife parasitism could impact long-term population health and survival.

Small changes in environmental parameters lead to alterations in antibiotic resistance, cell morphology and membrane fatty acid composition in Staphylococcus lugdunensis.

Directory of Open Access Journals (Sweden)

Marcus J Crompton

Full Text Available Staphylococcus lugdunensis has emerged as a major cause of community-acquired and nosocomial infections. This bacterium can rapidly adapt to changing environmental conditions to survive and capitalize on opportunities to colonize and infect through wound surfaces. It was proposed that S. lugdunensis would have underlying alterations in metabolic homeostasis to provide the necessary levels of adaptive protection. The aims of this project were to examine the impacts of subtle variations in environmental conditions on growth characteristics, cell size and membrane fatty acid composition in S. lugdunensis. Liquid broth cultures of S. lugdunensis were grown under varying combinations of pH (6-8, temperature (35-39°C and osmotic pressure (0-5% sodium chloride w/w to reflect potential ranges of conditions encountered during transition from skin surfaces to invasion of wound sites. The cells were harvested at the mid-exponential phase of growth and assessed for antibiotic minimal inhibitory concentration (MIC, generation time, formation of small colony variants, cell size (by scanning electron microscopy and membrane fatty acid composition. Stress regimes with elevated NaCl concentrations resulted in significantly higher antibiotic resistance (MIC and three of the combinations with 5% NaCl had increased generation times (P<0.05. It was found that all ten experimental growth regimes, including the control and centroid cultures, yielded significantly different profiles of plasma membrane fatty acid composition (P<0.0001. Alterations in cell size (P<0.01 were also observed under the range of conditions with the most substantial reduction occurring when cells were grown at 39°C, pH 8 (514±52 nm, mean ± Standard Deviation compared with cells grown under control conditions at 37°C with pH 7 (702±76 nm, P<0.01. It was concluded that S. lugdunensis responded to slight changes in environmental conditions by altering plasma membrane fatty acid composition

87Sr/86Sr and 143Nd/144Nd for disentangling anthropogenic and natural REE contributions in river water during flood events.

Science.gov (United States)

Hissler, Christophe; Stille, Peter; Pfister, Laurent

2017-04-01

The sustainable management of water resources is one of the greatest challenges of the 21st century. Water is a vital resource that is increasingly put under pressure from multiple perspectives. While the global population is on the rise, socio-economic development makes equally rapid progress - eventually compromising access to clean water bodies. Multiple pollution sources constitute an immediate threat to aquatic ecosystems and are likely to cause long lasting contaminations of water bodies that are critical for drinking and/or irrigation water production. There is a pressing need for an adequate quantification of anthropogenic impacts on the critical zone of river basins and the identification of the temporal dynamics of these impacts. As an example, despite the work done to assess the environmental impact of REE pollutions in larger river systems, we are still lacking information on the dynamics of these anthropogenic compounds in relation to rapid hydrological changes. Filling these knowledge gaps is a pre-requisite for the design and implementation of sustainable water resources management strategies. In order to better constrain the relative contributions of both anthropogenic and geogenic trace element sources we propose using a multitracer approach combining elemental and 87Sr/86Sr, 143Nd/144Nd, and 206Pb/207Pb isotopic ratios. The use of these three separate isotopic systems together with REE concentrations is new in the field of anthropogenic source identification in river systems. We observed enrichments in Anthropogenic Rare Earth Elements (AREE) for dissolved Gd and suspended Nd loads of river water. With increasing discharge, AREE anomalies progressively disappeared and gave way to the geogenic chemical signature of the basin in both dissolved and suspended loads. The isotopic data confirm these observations and shed new light on the trace elements sources. On the one hand, dissolved loads have peculiar isotopic characteristics and carry mainly

Long-term Increases in Flower Production by Growth Forms in Response to Anthropogenic Change in a Tropical Forest

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Pau, S.; Wright, S. J.

2016-12-01

There is mounting evidence that anthropogenic global change is altering the ecology of tropical forests. A limited number of studies have focused on long-term trends in tropical reproductive activity, yet differences in reproductive activity should have consequences for demography and ultimately forest carbon, water, and energy balance. Here we analyze a 28-year record of tropical flower production in response to anthropogenic climate change. We show that a multi-decadal increase in flower production is most strongly driven by rising atmospheric CO2, which had approximately 8x the effect of the Multivariate ENSO Index and approximately 13x the effect of rainfall or solar radiation. Interannual peaks in flower production were associated with greater solar radiation and low rainfall during El Niño years. Observed changes in solar radiation explained flower production better than rainfall (models including solar radiation accounted for 94% of cumulative AICc weight compared to 87% for rainfall). All growth forms (lianas, canopy trees, midstory trees, and shrubs) produced more flowers with increasing CO2 except for understory treelets. The increase in flower production was matched by a lengthening of flowering duration for canopy trees and midstory trees; duration was also longer for understory treelets. Given that anthropogenic CO2 emissions will continue to climb over the next century, the long-term increase in flower production may persist unless offset by increasing cloudiness in the tropics, or until rising CO2 and/or warming temperatures associated with the greenhouse effect pass critical thresholds for plant reproduction.

Atmospheric delivery of anthropogenic bioavailable iron from mineral dust to the ocean

OpenAIRE

伊藤, 彰記; 時, 宗波; ITO, Akinori; SHI, Zongbo

2015-01-01

Atmospheric deposition of anthropogenic soluble iron (Fe) to the ocean has been suggested to modulate primary ocean productivity and thus indirectly affect the climate. A key process contributing to anthropogenic sources of soluble Fe is associated with air pollution, which acidifies Fe-containing mineral aerosols during their transport and leads to Fe transformation from insoluble to soluble forms. However, there is large uncertainty in our estimate of this anthropogenic soluble Fe. Here, we...

The Early Anthropogenic Hypothesis: Top-Down and Bottom-up Evidence

Science.gov (United States)

Ruddiman, W. F.

2014-12-01

Two complementary lines of evidence support the early anthropogenic hypothesis. Top-down evidence comes from comparing Holocene greenhouse-gas trends with those during equivalent intervals of previous interglaciations. The increases in CO2 and CH4 during the late Holocene are anomalous compared to the decreasing trends in a stacked average of previous interglaciations, thereby supporting an anthropogenic origin. During interglacial stage 19, the closest Holocene insolation analog, CO2 fell to 245 ppm by the time equivalent to the present, in contrast to the observed pre-industrial rise to 280-285 ppm. The 245-ppm level measured in stage 19 falls at the top of the natural range predicted by the original anthropogenic hypothesis of Ruddiman (2003). Bottom-up evidence comes from a growing list of archeological and other compilations showing major early anthropogenic transformations of Earth's surface. Key examples include: efforts by Dorian Fuller and colleagues mapping the spread of irrigated rice agriculture across southern Asia and its effects on CH4 emissions prior to the industrial era; an additional effort by Fuller showing the spread of methane-emitting domesticated livestock across Asia and Africa (coincident with the spread of fertile crescent livestock across Europe); historical compilations by Jed Kaplan and colleagues documenting very high early per-capita forest clearance in Europe, thus underpinning simulations of extensive pre-industrial clearance and large CO2 emissions; and wide-ranging studies by Erle Ellis and colleagues of early anthropogenic land transformations in China and elsewhere.

Climate and anthropogenic contributions to the desiccation of the second largest saline lake in the twentieth century

Science.gov (United States)

Chaudhari, Suyog; Felfelani, Farshid; Shin, Sanghoon; Pokhrel, Yadu

2018-05-01

Urmia Lake, once the second largest saline lake in the world, is on the verge of complete desiccation. It has been suggested that the desiccation is caused by intensified human activities, especially irrigation, and prolonged droughts in the lake basin, but there is a lack of quantitative analysis to attribute the observed water level decline to natural and anthropogenic causes. In this study, we use remote sensing data, ground observations, and a hydrological model with human impact assessment capabilities (HiGW-MAT) to investigate the natural and human-induced changes in the hydrology of Urmia Lake basin from 1980 to 2010. Based on the analysis of remote sensing data, we find a ∼98% and ∼180% increase in agricultural lands and urban areas, respectively, from 1987 through 2016, with a corresponding shrinkage in lake area by ∼86%. Further, we use model results to examine the changes in terrestrial water storage (TWS) over the basin including the lake. Results indicate that TWS declined over the lake region and the lake lost water at a faster rate than the watershed did. Comparison of river inflow to the lake from two simulations-one with and the other without human activities-suggests that human water management activities caused a reduction in streamflow of ∼1.74 km3/year from 1995 to 2010, which accounts for ∼86% of the total depletion in lake volume during the same period. It is also found that irrigation water requirement almost tripled, causing high withdrawals from rivers. These results demonstrate that the on-going depletion of Urmia Lake is not solely due to prolonged droughts but also due to direct anthropogenic alterations which caused significant changes in land use, streamflow, and water storage within the basin. This study provides important insights on the natural and human-induced changes in the hydrology of Urmia Lake and highlights the need for a high resolution regional scale modeling approach for better understanding potential future

Direct radiative effects by anthropogenic particles at a polluted site: Rome (Italy)

International Nuclear Information System (INIS)

Bergamo, A.; De Tomasi, F.; Perrone, M.R.

2008-01-01

The direct radiative effect (DRE) by all (anthropogenic plus natural) and anthropogenic aerosols is calculated at the solar (0.34 μm) and infrared (4-200 μm) spectral range to better address the annual cycle of the anthropogenic aerosols impact at a site (Rome, Italy) significantly affected by pollution. Aerosol optical and microphysical properties from 2003 AERONET Sun/sky-photometer measurements and solar albedos based on MODIS satellite sensor data constitute the necessary input to radiative transfer simulations. Clear- and all-sky conditions are investigated by adopting ISCCP monthly products for high-, mid-and low-cloud cover. It is shown that monthly mean values of aerosol optical depths by anthropogenic particles (AOD a ) are on average more than 50% of the corresponding all-aerosol-optical-depth (AOD) monthly means. In particular, the AOD a /AOD ratio that varies within the (0.51-0.83) on autumn-winter (A W, October-March), varies within the (0.50-0.71 range on spring-summer (S S, April-September) as a consequence of the larger contribution of natural particles on S S. The surface (sfc), all-sky DRE by anthropogenic particles that is negative all year round at solar wave-lengths, represents on average 60% and 51% of the all-sky sfc-DRE by all aerosols on A W and S S, respectively. The all-sky atmospheric forcing by anthropogenic particles (AF a ) that is positive all year round, is little dependent on seasons: it varies within the (1.0-4.1) W/m 2 and (2.0-4.2) W/m 2 range an A W and S S, respectively. Conversely, the all-sky A F by all aerosols is characterized by a marked seasonality. As a consequence, the atmospheric forcing by anthropogenic particles that on average is 50% of the A F value on A W, decreases down to 36% of the A F value on S S. Infrared aerosols DREs that are positive all year round are significantly smaller than the corresponding absolute values of solar DREs. Clouds decrease on average ToA- and sfc-DRE absolute values by anthropogenic

Environmental and anthropogenic factors affecting the probability of occurrence of Oncomegas wageneri (Cestoda: Trypanorhyncha) in the southern Gulf of Mexico.

Science.gov (United States)

Vidal-Martínez, Víctor M; Torres-Irineo, Edgar; Romero, David; Gold-Bouchot, Gerardo; Martínez-Meyer, Enrique; Valdés-Lozano, David; Aguirre-Macedo, M Leopoldina

2015-11-26

Understanding the environmental and anthropogenic factors influencing the probability of occurrence of the marine parasitic species is fundamental for determining the circumstances under which they can act as bioindicators of environmental impact. The aim of this study was to determine whether physicochemical variables, polyaromatic hydrocarbons or sewage discharge affect the probability of occurrence of the larval cestode Oncomegas wageneri, which infects the shoal flounder, Syacium gunteri, in the southern Gulf of Mexico. The study area included 162 sampling sites in the southern Gulf of Mexico and covered 288,205 km(2), where the benthic sediments, water and the shoal flounder individuals were collected. We used the boosted generalised additive models (boosted GAM) and the MaxEnt to examine the potential statistical relationships between the environmental variables (nutrients, contaminants and physicochemical variables from the water and sediments) and the probability of the occurrence of this parasite. The models were calibrated using all of the sampling sites (full area) with and without parasite occurrences (n = 162) and a polygon area that included sampling sites with a depth of 1500 m or less (n = 134). Oncomegas wageneri occurred at 29/162 sampling sites. The boosted GAM for the full area and the polygon area accurately predicted the probability of the occurrence of O. wageneri in the study area. By contrast, poor probabilities of occurrence were obtained with the MaxEnt models for the same areas. The variables with the highest frequencies of appearance in the models (proxies for the explained variability) were the polyaromatic hydrocarbons of high molecular weight (PAHH, 95 %), followed by a combination of nutrients, spatial variables and polyaromatic hydrocarbons of low molecular weight (PAHL, 5 %). The contribution of the PAHH to the variability was explained by the fact that these compounds, together with N and P, are carried by rivers that

Anthropogenic heat flux estimation from space

NARCIS (Netherlands)

Chrysoulakis, Nektarios; Marconcini, Mattia; Gastellu-Etchegorry, Jean Philippe; Grimmond, C.S.B.; Feigenwinter, Christian; Lindberg, Fredrik; Frate, Del Fabio; Klostermann, Judith; Mitraka, Zina; Esch, Thomas; Landier, Lucas; Gabey, Andy; Parlow, Eberhard; Olofson, Frans

2016-01-01

H2020-Space project URBANFLUXES (URBan ANthrpogenic heat FLUX from Earth observation Satellites) investigates the potential of Copernicus Sentinels to retrieve anthropogenic heat flux, as a key component of the Urban Energy Budget (UEB). URBANFLUXES advances the current knowledge of the impacts

ANthropogenic heat FLUX estimation from Space

NARCIS (Netherlands)

Chrysoulakis, Nektarios; Marconcini, Mattia; Gastellu-Etchegorry, Jean Philippe; Grimmong, C.S.B.; Feigenwinter, Christian; Lindberg, Fredrik; Frate, Del Fabio; Klostermann, Judith; Mi, Zina; Esch, Thomas; Landier, Lucas; Gabey, Andy; Parlow, Eberhard; Olofson, Frans

2017-01-01

The H2020-Space project URBANFLUXES (URBan ANthrpogenic heat FLUX from Earth observation Satellites) investigates the potential of Copernicus Sentinels to retrieve anthropogenic heat flux, as a key component of the Urban Energy Budget (UEB). URBANFLUXES advances the current knowledge of the

Antibiotic resistance marker genes as environmental pollutants in GMO-pristine agricultural soils in Austria

International Nuclear Information System (INIS)

Woegerbauer, Markus; Zeinzinger, Josef; Gottsberger, Richard Alexander; Pascher, Kathrin; Hufnagl, Peter; Indra, Alexander; Fuchs, Reinhard; Hofrichter, Johannes; Kopacka, Ian; Korschineck, Irina

2015-01-01

Antibiotic resistance genes may be considered as environmental pollutants if anthropogenic emission and manipulations increase their prevalence above usually occurring background levels. The prevalence of aph(3′)-IIa/nptII and aph(3′)-IIIa/nptIII – frequent marker genes in plant biotechnology conferring resistance to certain aminoglycosides – was determined in Austrian soils from 100 maize and potato fields not yet exposed to but eligible for GMO crop cultivation. Total soil DNA extracts were analysed by nptII/nptIII-specific TaqMan real time PCR. Of all fields 6% were positive for nptII (median: 150 copies/g soil; range: 31–856) and 85% for nptIII (1190 copies/g soil; 13–61600). The copy-number deduced prevalence of nptIII carriers was 14-fold higher compared to nptII. Of the cultivable kanamycin-resistant soil bacteria 1.8% (95% confidence interval: 0–3.3%) were positive for nptIII, none for nptII (0–0.8%). The nptII-load of the studied soils was low rendering nptII a typical candidate as environmental pollutant upon anthropogenic release into these ecosystems. - Highlights: • ARM genes may act as environmental pollutants under certain conditions. • Vital criteria for rating are low endemic presence and anthropogenic ARG immission. • Agricultural soils were rarely positive for nptII with few gene copy numbers. • Most fields were nptIII positive with variable but also increased allele frequency. • NptII/III qualify as pollutants in the tested settings with low endemic abundances. - ARM genes may be considered as environmental pollutants if anthropogenic activities raise their abundance above naturally occurring background levels in exposed ecosystems.

Influence of natural and anthropogenic factors on the distribution of xerothermic plants in the lower San river valley (SE Poland

Directory of Open Access Journals (Sweden)

Rafał Krawczyk

2012-12-01

Full Text Available The aim of the present study was to describe the distribution of xerothermic species of vascular plants in the lower San River valley and the relationship between their density and the intensity of selected environmental (natural and anthropogenic factors. Xerothermic species occurred more frequently in the present valley floor compared to the glacial terrace. Within the present valley, the highest density was observed in the floodplain. The examined species also occurred more often on steep slopes of the valley, at the margins of the present valley terraces, and in the area of occurrence of aeolian sands. Moreover, a positive correlation has been found between the number of xerothermic species and the area of polyhemeroby ecosystems. The distribution of xero- and thermophilous species is determined by natural edaphic and geomorphological factors as well as anthropogenic ones (land use, lowering of the groundwater level as a result of river regulation.

The relative abundance of predicted genes associated with ammonia-oxidation, nitrate reduction, and biomass decomposition in mineral soil are altered by intensive timber harvest.

Science.gov (United States)

Mushinski, R. M.; Zhou, Y.; Gentry, T. J.; Boutton, T. W.

2017-12-01

Forest ecosystems in the southern United States are substantially altered by anthropogenic disturbances such as timber harvest and land conversion, with effects being observed in carbon and nutrient pools as well as biogeochemical processes. Furthermore, the desire to develop renewable energy sources in the form of biomass extraction from logging residues may result in alterations in soil community structure and function. While the impact of forest management on soil physicochemical properties of the region has been studied, its' long-term effect on soil bacterial community composition and metagenomic potential is relatively unknown, especially at deeper soil depths. This study investigates how intensive organic matter removal intensities associated with timber harvest influence decadal-scale alterations in bacterial community structure and functional potential in the upper 1-m of the soil profile, 18 years post-harvest in a Pinus taeda L. forest of eastern Texas. Amplicon sequencing of the 16S rRNA gene was used in conjunction with soil chemical analyses to evaluate treatment-induced differences in community composition and potential environmental drivers of associated change. Furthermore, functional potential was assessed by using amplicon data to make metagenomic predictions. Results indicate that increasing organic matter removal intensity leads to altered community composition and the relative abundance of dominant OTUs annotated to Burkholderia and Aciditerrimonas. The relative abundance of predicted genes associated with dissimilatory nitrate reduction and denitrification were highest in the most intensively harvested treatment while genes involved in nitrification were significantly lower in the most intensively harvested treatment. Furthermore, genes associated with glycosyltransferases were significantly reduced with increasing harvest intensity while polysaccharide lyases increased. These results imply that intensive organic matter removal may create

Characterizing the anthropogenic signature in the LCLU dynamics in the Central Asia region

Science.gov (United States)

Tatarskii, V.; Sokolik, I. N.; de Beurs, K.; Shiklomanov, A. I.

2017-12-01

Humans have been changing the LCLU dynamics over time through the world. In the Central Asia region, these changes have been especially pronounced due to the political and economic transformation. We present a detailed analysis, focusing on identifying and quantifying the anthropogenic signature in the water and land use across the region. We have characterized the anthropogenic dust emission by combining the modeling and observations. The model is a fully coupled model called WRF-Chem-DuMo that takes explicitly into account the vegetation treatment in modeling the dust emission. We have reconstructed the anthropogenic dust sources in the region, such as the retreat of the Aral Sea, changes in agricultural fields, etc. In addition, we characterize the anthropogenic water use dynamics, including the changes in the water use for the agricultural production. Furthermore, we perform an analysis to identify the anthropogenic signature in the NDVI pattern. The NDVI were analyzed in conjunction with the meteorological fields that were simulated at the high special resolution using the WRF model. Meteorological fields of precipitation and temperature were used for the correlation analysis to separate the natural vs. anthropogenic changes. In this manner, we were able to identify the regions that have been affected by human activities. We will present the quantitative assessment of the anthropogenic changes. The diverse consequences for the economy of the region, as well as, the environment will be addressed.

Environmental pollution. Uni-Taschenbuecher

Energy Technology Data Exchange (ETDEWEB)

Odzuck, W

1982-01-01

The volume of the anthropogenic pollution of the environment (incl. radioactivity) is of great economical importance and has also a meaning to the health and happiness of people. The pocket book introduces into the whole problem by giving exact information and data. After a general survey, the pollutions of urban-industrial, and aquatic ecosystems are dealt with. The book closes with indications as to general principles, specific dangers, and the future development of the environmental pollution.

Anthropogenic Cycles of Rare Earth Elements

Science.gov (United States)

Du, X.; Graedel, T. E.

2009-12-01

This research will develop quantitatively resolved anthropogenic cycles and in-use stocks for the rare earth metals specifically cerium, lanthanum and dysprosium in Japan, China, and the U.S. for the year of 2007. Rare earth elements (REE) is a group of 17 scare metals widely used in a growing number of emerging technologies and have been in high demand for emerging technologies as raw materials during past the three decades. New market participants from newly industrializing countries, primarily China, have had strong impacts on the demand of share. Consequently, the importance to sustain a reliable, steady, uninterrupted supply on global market triggered comprehensive research to recognize and understand the life cycles of rare earths. Moreover, because China plays a dominant role in mining production since 1990, it requires the assessment for the countries, which are almost completely dependent on imports from China with respect to rare earth resources. The study aims to analyze the flows and stocks of rare earth elements individually as elemental form in spite of their natural geological co-occurrence and mixed composition in applications. By applying the method of Material Flow Analysis (MFA) work has been done on evaluating current and historical flows of specific technologically significant materials, for example, copper, zinc, nickel, etc., determining the stocks available in different types of reservoirs (e.g., lithosphere, in-use) and the flows among the reservoirs, developing scenarios of possible futures of metal use, and assessing the environmental and policy implications of the results. Therefore, REE as a new target deserves inclusion because of its potential demand-supply conflict and importance to secure the competitive advantage of technical innovation in future. This work will generate a quantitatively resolved anthropogenic life cycle and in-use stocks for REE for the main target countries for a chosen year, 2007, providing flows and stocks from

Climate Impacts From a Removal of Anthropogenic Aerosol Emissions

Science.gov (United States)

Samset, B. H.; Sand, M.; Smith, C. J.; Bauer, S. E.; Forster, P. M.; Fuglestvedt, J. S.; Osprey, S.; Schleussner, C.-F.

2018-01-01

Limiting global warming to 1.5 or 2.0°C requires strong mitigation of anthropogenic greenhouse gas (GHG) emissions. Concurrently, emissions of anthropogenic aerosols will decline, due to coemission with GHG, and measures to improve air quality. However, the combined climate effect of GHG and aerosol emissions over the industrial era is poorly constrained. Here we show the climate impacts from removing present-day anthropogenic aerosol emissions and compare them to the impacts from moderate GHG-dominated global warming. Removing aerosols induces a global mean surface heating of 0.5-1.1°C, and precipitation increase of 2.0-4.6%. Extreme weather indices also increase. We find a higher sensitivity of extreme events to aerosol reductions, per degree of surface warming, in particular over the major aerosol emission regions. Under near-term warming, we find that regional climate change will depend strongly on the balance between aerosol and GHG forcing.

Estimation of the Relationship Between Remotely Sensed Anthropogenic Heat Discharge and Building Energy Use

Science.gov (United States)

Zhou, Yuyu; Weng, Qihao; Gurney, Kevin R.; Shuai, Yanmin; Hu, Xuefei

2012-01-01

This paper examined the relationship between remotely sensed anthropogenic heat discharge and energy use from residential and commercial buildings across multiple scales in the city of Indianapolis, Indiana, USA. The anthropogenic heat discharge was estimated with a remote sensing-based surface energy balance model, which was parameterized using land cover, land surface temperature, albedo, and meteorological data. The building energy use was estimated using a GIS-based building energy simulation model in conjunction with Department of Energy/Energy Information Administration survey data, the Assessor's parcel data, GIS floor areas data, and remote sensing-derived building height data. The spatial patterns of anthropogenic heat discharge and energy use from residential and commercial buildings were analyzed and compared. Quantitative relationships were evaluated across multiple scales from pixel aggregation to census block. The results indicate that anthropogenic heat discharge is consistent with building energy use in terms of the spatial pattern, and that building energy use accounts for a significant fraction of anthropogenic heat discharge. The research also implies that the relationship between anthropogenic heat discharge and building energy use is scale-dependent. The simultaneous estimation of anthropogenic heat discharge and building energy use via two independent methods improves the understanding of the surface energy balance in an urban landscape. The anthropogenic heat discharge derived from remote sensing and meteorological data may be able to serve as a spatial distribution proxy for spatially-resolved building energy use, and even for fossil-fuel CO2 emissions if additional factors are considered.

Balancing the risks of habitat alteration and environmental contamination in a contaminated forested wetland

International Nuclear Information System (INIS)

Bleiler, J.A.; Daukas, G.; Richardson, N.

1994-01-01

The North Lawrence Oil Dump Site (NLODS) is an inactive hazardous waste site located adjacent to an extensive palustrine forested wetland in upstate New York. Waste oil and oil sludge were disposed of in a lagoon adjacent to the wetland during the 1960s. During periods of high water, oils escaped from the lagoon and were transported into the wetlands. High concentrations of lead and PCBs were detected in NLODS wetland sediments, and contaminants from the site were present in wetland's plant and animal tissues. However, contaminated portions of the wetlands appear to be physically undisturbed and provide high quality wildlife habitat. The results of an ecological risk assessment indicated that lead and PCB contamination in NLODS sediment may be impacting some components of the wetlands community. The risk management process considered both the toxicological risks associated with lead and PCB contamination, as well as the significant habitat destruction risks associated with remediation. Six potential PCB target cleanup levels were evaluated. Following removal of sediments with PCB contamination greater than 0.5 mg/kg, 3.5 acres of sediment with lead contamination in excess of 250 mg/kg (the New York State ''Severe Effect Level'') would remain. More than 1.5 of these acres would contain lead concentrations in excess of 1,000 mg/kg. Reducing lead levels to background concentrations would require more than 50 acres of wetlands alteration. The Record of Decision at the NLODS recognized the high quality habitat provided by the site's wetlands, and attempted to balance the risks from habitat alteration with the risks of environmental contamination

Recent trends of environmental radioactivity in Greenland and the Faroe Islands

DEFF Research Database (Denmark)

Nielsen, Sven Poul; Joensen, H.P.

2009-01-01

Environmental radioactivity in Greenland and the Faroe Islands was investigated from samples collected in 2004 of seawater, seaweed, marine fish, seal, whale, lake water, freshwater fish and total diet. Anthropogenic radionuclides in Greenland and the Faroe Islands are present due to long......-range transport by air and water mainly due to fallout from nuclear weapons testing, from the Chernobyl accident and discharges from European reprocessing facilities, Sellafield in the UK and La Hague in France. Concentrations of anthropogenic radionuclides in environment and food are low, however, and present...... insignificant health risks to humans. Naturally occurring radionuclides are present in the environment and human food and dominate the radiation dose from ingestion. Even in case of landlocked Arctic char from South Greenland showing elevated concentrations of anthropogenic 137Cs, the radiation doses to man...

CLASSIFICATION OF ANTHROPOGENIC TRANSFORMATIONS SOILS URBOECOSYSTEMS OF DNEPROPETROVSK

Directory of Open Access Journals (Sweden)

YAKOVYSHYNA T.F.

2015-12-01

Full Text Available Raising of problem. The functioning of the city, as artificially created system of the result of the anthropogenic activity, promotes degradation and, sometimes, destruction of the environment, with change it to the technogenic replacement. First of all suffers the soil, as a basic component of any ecosystem, where the circulation of materials close, because it is a powerful biogeochemical barrier to their migration, able to deposit toxicants a long time through its protective functions. The leading role of the formation of the urban soil plays an anthropogenic factor, which is able to influence directly – the destruction of the soil profile due to construction activity and indirectly – with aerogenic or hydrogenous pollution xenobiotics contained in the emissions and discharges of the industrial enterprises; and it is determined by the type of economic use and history of area developing. The variability of using the urban soil is reflected in the soil profile and contributed to the creation of the organic-mineral layer by the mixing, mound, burial and (or contamination of the different substances on the surface. Therefore, classification of the urban soils by the anthropogenic destruction degree of the soil profile is very important scientific and practical task for the urban ecology to the achievement standards of the ecological safety of the modern city, because the restoring of their protective functions is impossible without knowledge of the morphological structure. Purpose. Classify the anthropogenical soils of city Dnipropetrovsk disturbed by the construction activities by the determining of the morphological characteristics of the soil profile structure with separation of the anthropogenic and technogenic surface formations compared to the zonal soil – ordinery chernozem. Conclusion. Within urboecosystem city Dnipropetrovsk long-term human impact to the zonal soil – chernozem led to its transformation into urbanozem witch

Plankton food-web functioning in anthropogenically impacted coastal waters (SW Mediterranean Sea): An ecological network analysis

Science.gov (United States)

Meddeb, Marouan; Grami, Boutheïna; Chaalali, Aurélie; Haraldsson, Matilda; Niquil, Nathalie; Pringault, Olivier; Sakka Hlaili, Asma

2018-03-01

combined with ecological indices provide a powerful approach to detect change in environmental status and anthropogenic impacts.

Anthropogenic disturbance on the vegetation in makurunge

African Journals Online (AJOL)

Mgina

landscape in Tanzania that has been severely affected by anthropogenic disturbance ... Fragmentation of habitats formed patches that have reduced plant species population sizes, and ... by the movement of the Inter-Tropical ..... of pollinators.

Anthropogenic heavy metals in the environment of Eurasian Arctic Nature Reserves

Science.gov (United States)

Vinogradova, Anna; Ivanova, Yulia; Karpov, Alexey

2014-05-01

The Russian Arctic Nature Reserves are situated far from the main industrial regions. In spite of this, there are anthropogenic constituents (for example, heavy metals - HM) in the environmental objects (air, water, etc.) and in food chains (plants, birds, and so on). We studied the long-range atmospheric transport of some heavy metals (such as nickel, copper, lead, arsenic, and so on) to four Nature Reserves situated near the shore of the Arctic Ocean - in the Deltas of the Pechora River (Nenets reserve), the Ob River (Gydansky reserve), the Lena River (Ust-Lensky reserve), and at Wrangel Island. The air mass trajectories to each reserve were calculated with the help of the site (www.arl.noaa.gov/ready) for each day of January, April, July, and October for the period of 2001-2010. Analyzing the spatial distributions of these trajectories we studied seasonal variations in air transport of pollution to different Russian Arctic points. Modeling the HM transport in the atmosphere was as in [1]. The main assumption is that HM are transported with submicron aerosol particles. The annual source emissions for the last decade are generalized from the data published by Roshydromet of Russia (http://www.nii-atmosphere.ru/files/PUBL/Eg_2008.doc). The main important source-regions were found for each point. Mean anthropogenic HM concentrations in air and precipitations, as well as HM fluxes onto the surface were estimated at different arctic regions. The spatial distributions of so called "potential function of pollution" were calculated and presented on the maps. These results allow to analyze the role of a real pollution source or of a planned source for each reserve. So, the influence of northern oil and gas industry may be of great importance because of its proximity to the reserves under investigation. The work was partly supported by RFBR, grant No. 14-05-00059. Authors thank the NOAA service for possibility to use their data and products. ________________ 1. Vinogradova

Development of a national anthropogenic heating database with an extrapolation for international cities

Science.gov (United States)

Sailor, David J.; Georgescu, Matei; Milne, Jeffrey M.; Hart, Melissa A.

2015-10-01

Given increasing utility of numerical models to examine urban impacts on meteorology and climate, there exists an urgent need for accurate representation of seasonally and diurnally varying anthropogenic heating data, an important component of the urban energy budget for cities across the world. Incorporation of anthropogenic heating data as inputs to existing climate modeling systems has direct societal implications ranging from improved prediction of energy demand to health assessment, but such data are lacking for most cities. To address this deficiency we have applied a standardized procedure to develop a national database of seasonally and diurnally varying anthropogenic heating profiles for 61 of the largest cities in the United Stated (U.S.). Recognizing the importance of spatial scale, the anthropogenic heating database developed includes the city scale and the accompanying greater metropolitan area. Our analysis reveals that a single profile function can adequately represent anthropogenic heating during summer but two profile functions are required in winter, one for warm climate cities and another for cold climate cities. On average, although anthropogenic heating is 40% larger in winter than summer, the electricity sector contribution peaks during summer and is smallest in winter. Because such data are similarly required for international cities where urban climate assessments are also ongoing, we have made a simple adjustment accounting for different international energy consumption rates relative to the U.S. to generate seasonally and diurnally varying anthropogenic heating profiles for a range of global cities. The methodological approach presented here is flexible and straightforwardly applicable to cities not modeled because of presently unavailable data. Because of the anticipated increase in global urban populations for many decades to come, characterizing this fundamental aspect of the urban environment - anthropogenic heating - is an essential

Visual attention based detection of signs of anthropogenic activities in satellite imagery

Energy Technology Data Exchange (ETDEWEB)

Skurikhin, Alexei N [Los Alamos National Laboratory

2010-10-13

With increasing deployment of satellite imaging systems, only a small fraction of collected data can be subject to expert scrutiny. We present and evaluate a two-tier approach to broad area search for signs of anthropogenic activities in high-resolution commercial satellite imagery. The method filters image information using semantically oriented interest points by combining Harris corner detection and spatial pyramid matching. The idea is that anthropogenic structures, such as rooftop outlines, fence corners, road junctions, are locally arranged in specific angular relations to each other. They are often oriented at approximately right angles to each other (which is known as rectilinearity relation). Detecting the rectilinearity provides an opportunity to highlight regions most likely to contain anthropogenic activity. This is followed by supervised classification of regions surrounding the detected corner points as man-made vs. natural scenes. We consider, in particular, a search for anthropogenic activities in uncluttered areas. In this paper, we proposed and evaluated a two-tier approach to broad area search for signs of anthropogenic activities. Results from experiments on high-resolution ({approx}0.6m) commercial satellite image data showed the potential applicability of this approach and its ability of achieving both high precision and recall rates. The main advantage of combining corner-based cueing with general object recognition is that the incorporation of domain specific knowledge even in its more general form, such as presence of comers, provides a useful cue to narrow the focus of search for signs of anthropogenic activities. Combination of comer based cueing with spatial pyramid matching addressed the issue of comer categorization. An important practical issue for further research is optimizing the balance between false positive and false negative rates. While the results presented in the paper are encouraging, the problem of an automated broad area

Anthropogenic forcing dominates sea level rise since 1850

DEFF Research Database (Denmark)

Jevrejeva, Svetlana; Grinsted, Aslak; Moore, John

2009-01-01

The rate of sea level rise and its causes are topics of active debate. Here we use a delayed response statistical model to attribute the past 1000 years of sea level variability to various natural (volcanic and solar radiative) and anthropogenic (greenhouse gases and aerosols) forcings. We show...... that until 1800 the main drivers of sea level change are volcanic and solar radiative forcings. For the past 200 years sea level rise is mostly associated with anthropogenic factors. Only 4 ± 1.5 cm (25% of total sea level rise) during the 20th century is attributed to natural forcings, the remaining 14 ± 1...

Preliminary assessment of factors influencing riverine fish communities in Massachusetts.

Science.gov (United States)

Armstrong, David S.; Richards, Todd A.; Brandt, Sara L.

2010-01-01

The U.S. Geological Survey, in cooperation with the Massachusetts Department of Conservation and Recreation (MDCR), Massachusetts Department of Environmental Protection (MDEP), and the Massachusetts Department of Fish and Game (MDFG), conducted a preliminary investigation of fish communities in small- to medium-sized Massachusetts streams. The objective of this investigation was to determine relations between fish-community characteristics and anthropogenic alteration, including flow alteration and impervious cover, relative to the effect of physical basin and land-cover (environmental) characteristics. Fish data were obtained for 756 fish-sampling sites from the Massachusetts Division of Fisheries and Wildlife fish-community database. A review of the literature was used to select a set of fish metrics responsive to flow alteration. Fish metrics tested include two fish-community metrics (fluvial-fish relative abundance and fluvial-fish species richness), and five indicator species metrics (relative abundance of brook trout, blacknose dace, fallfish, white sucker, and redfin pickerel). Streamflows were simulated for each fish-sampling site using the Sustainable Yield Estimator application (SYE). Daily streamflows and the SYE water-use database were used to determine a set of indicators of flow alteration, including percent alteration of August median flow, water-use intensity, and withdrawal and return-flow fraction. The contributing areas to the fish-sampling sites were delineated and used with a Geographic Information System (GIS) to determine a set of environmental characteristics, including elevation, basin slope, percent sand and gravel, percent wetland, and percent open water, and a set of anthropogenic-alteration variables, including impervious cover and dam density. Two analytical techniques, quantile regression and generalized linear modeling, were applied to determine the association between fish-response variables and the selected environmental and

Diet, lifestyle, and molecular alterations that drive colorectal carcinogenesis

NARCIS (Netherlands)

Diergaarde, B.

2004-01-01

Environmental factors have been repeatedly implicated in the etiology of colorectal cancer, and much is known about the molecular events involved in colorectal carcinogenesis. The relationships between environmental risk factors and the molecular alterations that drive colorectal carcinogenesis are

Environmental prenatal stress eliminates brain and maternal behavioral sex differences and alters hormone levels in female rats.

Science.gov (United States)

Del Cerro, M C R; Ortega, E; Gómez, F; Segovia, S; Pérez-Laso, C

2015-07-01

Environmental prenatal stress (EPS) has effects on fetuses that are long-lasting, altering their hormone levels, brain morphology and behavior when they reach maturity. In previous research, we demonstrated that EPS affects the expression of induced maternal behavior (MB), the neuroendocrine system, and morphology of the sexually dimorphic accessory olfactory bulb (AOB) involved in reproductive behavior patterns. The bed nucleus of the accessory olfactory tract (BAOT) is another vomeronasal (VN) structure that plays an inhibitory role in rats in the expression of induced maternal behavior in female and male virgins. In the present study, we have ascertained whether the behavioral, neuroendocrine, and neuromorphological alterations of the AOB found after EPS also appear in the BAOT. After applying EPS to pregnant rats during the late gestational period, in their female offspring at maturity we tested induced maternal behavior, BAOT morphology and plasma levels of testosterone (T), estradiol (E2), progesterone (P), adrenocorticotropic hormone (ACTH) and corticosterone (Cpd B). EPS: a) affected the induction of MB, showed a male-like pattern of care for pups, b) elevated plasma levels of Cpd B and reduced E2 in comparison with the controls, and c) significantly increased the number of BAOT neurons compared to the control females and comparable to the control male group. These findings provide further evidence that stress applied to pregnant rats produces long-lasting behavioral, endocrine and neuroanatomical alterations in the female offspring that are evident when they become mature. Copyright © 2015 Elsevier Inc. All rights reserved.

Celtic field agriculture and Early Anthropogenic Environmental change in soil records of the Meuse-Demer-Scheldt region, NW Europe.

Science.gov (United States)

Van der Sanden, Germaine; Kluiving, Sjoerd; Roymans, Nico

2017-04-01

Archaeological research is fundamental in the process of obtaining a greater understanding on the intricate dynamics between the human species and the 'natural' environment. Deep historical processes can evaluate the complex interactions that eventually led to the human species as the dominating agent, in terms of the Earth's biotic and abiotic processes. Regional landscape studies can determine whether the human species can be evaluated as a formative element in soil formation processes during the Holocene. This study is directed to examine early anthropogenic land cover change (ALCC) in the Meuse-Demer-Scheldt region, in the southern Netherlands and northern Belgium, between the Late Bronze Age and Early Roman Period (1050-200 AD). The introduction of an extensive agricultural system, the Celtic field system, in co-relation with demographic rise, led to increased anthropogenic pressure on the MDS landscape. Throughout the Holocene, demographic rise pressured farmers to develop increasingly efficient and innovative methods of extracting more yields per unit area farmed resulting in a decrease in land use per capita over time (Kaplan et al. 2010; Boserup, 1965,1981)). The land use per capita under Celtic field technology was relatively high compared to contemporary numbers, based on the assumption that land use per capita did not remain constant. The MDS region is a clear example of early Holocene ALCC and modification of terrestrial ecosystems due to excessive clearance of vegetation. Early Holocene ALCC resulted in ecological deficiencies in the landscape, e.g. deforestation, acceleration of podzolisation and a decrease in terrestrial carbon storage as well as water retention capacity. ALCC can impact climate through biogeophysical and biogeochemical feedbacks to the atmosphere, and result in regional negative radiative forcing. Here we hypothesize that the previously presumed fundamental restructuring that led to a structural bipartition in the landscape due to

Anthropogenic and ecological drivers of amphibian disease (ranavirosis.

Directory of Open Access Journals (Sweden)

Alexandra C North

Full Text Available Ranaviruses are causing mass amphibian die-offs in North America, Europe and Asia, and have been implicated in the decline of common frog (Rana temporaria populations in the UK. Despite this, we have very little understanding of the environmental drivers of disease occurrence and prevalence. Using a long term (1992-2000 dataset of public reports of amphibian mortalities, we assess a set of potential predictors of the occurrence and prevalence of Ranavirus-consistent common frog mortality events in Britain. We reveal the influence of biotic and abiotic drivers of this disease, with many of these abiotic characteristics being anthropogenic. Whilst controlling for the geographic distribution of mortality events, disease prevalence increases with increasing frog population density, presence of fish and wild newts, increasing pond depth and the use of garden chemicals. The presence of an alternative host reduces prevalence, potentially indicating a dilution effect. Ranavirosis occurrence is associated with the presence of toads, an urban setting and the use of fish care products, providing insight into the causes of emergence of disease. Links between occurrence, prevalence, pond characteristics and garden management practices provides useful management implications for reducing the impacts of Ranavirus in the wild.

Simulations of the global carbon cycle and anthropogenic CO2 transient

International Nuclear Information System (INIS)

Sarmiento, J.L.

1994-01-01

This research focuses on improving the understanding of the anthropogenic carbon dioxide transient using observations and models of the past and present. In addition, an attempt is made to develop an ability to predict the future of the carbon cycle in response to continued anthropogenic perturbations and climate change. Three aspects of the anthropogenic carbon budget were investigated: (1) the globally integrated budget at the present time; (2) the time history of the carbon budget; and (3) the spatial distribution of carbon fluxes. One of the major activities of this study was the participation in the model comparison study of Enting, et al. [1994] carried out in preparation for the IPCC 1994 report

A Framework to Quantify the Strength of the Ecological Links Between an Environmental Stressor and Final Ecosystem Services

Science.gov (United States)

Anthropogenic stressors such as climate change, fire, and pollution are driving shifts in ecosystem function and resilience. Scientists generally rely on biological indicators of these stressors to signal that ecosystem conditions have been altered beyond an acceptable amount. Ho...

Nitrogen enrichment suppresses other environmental drivers and homogenizes salt marsh leaf microbiome.

Science.gov (United States)

Daleo, Pedro; Alberti, Juan; Jumpponen, Ari; Veach, Allison; Ialonardi, Florencia; Iribarne, Oscar; Silliman, Brian

2018-06-01

Microbial community assembly is affected by a combination of forces that act simultaneously, but the mechanisms underpinning their relative influences remain elusive. This gap strongly limits our ability to predict human impacts on microbial communities and the processes they regulate. Here, we experimentally demonstrate that increased salinity stress, food web alteration and nutrient loading interact to drive outcomes in salt marsh fungal leaf communities. Both salinity stress and food web alterations drove communities to deterministically diverge, resulting in distinct fungal communities. Increased nutrient loads, nevertheless, partially suppressed the influence of other factors as determinants of fungal assembly. Using a null model approach, we found that increased nutrient loads enhanced the relative importance of stochastic over deterministic divergent processes; without increased nutrient loads, samples from different treatments showed a relatively (deterministic) divergent community assembly whereas increased nutrient loads drove the system to more stochastic assemblies, suppressing the effect of other treatments. These results demonstrate that common anthropogenic modifications can interact to control fungal community assembly. Furthermore, our results suggest that when the environmental conditions are spatially heterogeneous (as in our case, caused by specific combinations of experimental treatments), increased stochasticity caused by greater nutrient inputs can reduce the importance of deterministic filters that otherwise caused divergence, thus driving to microbial community homogenization. © 2018 by the Ecological Society of America.

SOCIO-ECONOMIC AND LEGAL ASPECTS OF ENVIRONMENTAL CRIME IN UKRAINE

OpenAIRE

Tamara Hubanova; Olena Yara; Maryna Deineha

2017-01-01

The increased danger of environmental crime is primarily determined by an increase in anthropogenic pressure on the natural environment, which, in the conditions of the global environmental crisis, threatens to cause significant, often non-renewable, damage to the vital interests of man, society, and the state. Ukraine belongs to the countries with the worst ecological situation. Pollution of the environment reached unprecedented levels in recent years. The purpose of the study is to reveal t...

Masked expression of life-history traits in a highly variable environment

Science.gov (United States)

DeBoer, Jason A.; Fontaine, Joseph J.; Chizinski, Christopher J.; Pope, Kevin L.

2015-01-01

Differing life-history strategies may act as a constraint on reproductive expression that ultimately limits the ability of individual species to respond to changes in the magnitude or frequency of environmental variation, and potentially underlies the variation often inherent in phenotypic and evolved responses to anthropogenic change. Alternatively, if there are environmental cues that predict reproductive potential, differential expression of life-history strategies may represent differences in the adaptive capacity to optimize current reproductive value given variation in environmental conditions. We compared several aspects of walleye Sander vitreus spawning ecology at two reservoirs that differ in environmental variability (i.e., annual water-level fluctuation) to identify the capacity of phenotypic expression and the corresponding association with age. Despite significant differences in female body and liver masses between reservoirs that differ in environmental variability, we found no difference in reproductive investment measured by egg size and fecundity. Walleye in a highly variable environment appear to exhibit reproductive traits more typical of a short-lived life-history strategy, which may be resultant from the interaction of environmental and anthropogenic pressures. This finding emphasizes the need to identify the degree to which life-history expression represents physiological constraints versus ecological optimization, particularly as anthropogenic change continues to alter environmental conditions. 

Simulated anthropogenic CO2 storage and acidification of the Mediterranean Sea

Directory of Open Access Journals (Sweden)

J. Palmiéri

2015-02-01

Full Text Available Constraints on the Mediterranean Sea's storage of anthropogenic CO2 are limited, coming only from data-based approaches that disagree by more than a factor of two. Here we simulate this marginal sea's anthropogenic carbon storage by applying a perturbation approach in a high-resolution regional model. Our model simulates that, between 1800 and 2001, basin-wide CO2 storage by the Mediterranean Sea has increased by 1.0 Pg C, a lower limit based on the model's weak deep-water ventilation, as revealed by evaluation with CFC-12. Furthermore, by testing a data-based approach (transit time distribution in our model, comparing simulated anthropogenic CO2 to values computed from simulated CFC-12 and physical variables, we conclude that the associated basin-wide storage of 1.7 Pg, published previously, must be an upper bound. Out of the total simulated storage of 1.0 Pg C, 75% comes from the air–sea flux into the Mediterranean Sea and 25% comes from net transport from the Atlantic across the Strait of Gibraltar. Sensitivity tests indicate that the Mediterranean Sea's higher total alkalinity, relative to the global-ocean mean, enhances the Mediterranean's total inventory of anthropogenic carbon by 10%. Yet the corresponding average anthropogenic change in surface pH does not differ significantly from the global-ocean average, despite higher total alkalinity. In Mediterranean deep waters, the pH change is estimated to be between −0.005 and −0.06 pH units.

Drivers potentially influencing host-bat fly interactions in anthropogenic neotropical landscapes at different spatial scales.

Science.gov (United States)

Hernández-Martínez, Jacqueline; Morales-Malacara, Juan B; Alvarez-Añorve, Mariana Yolotl; Amador-Hernández, Sergio; Oyama, Ken; Avila-Cabadilla, Luis Daniel

2018-05-21

The anthropogenic modification of natural landscapes, and the consequent changes in the environmental conditions and resources availability at multiple spatial scales can affect complex species interactions involving key-stone species such as bat-parasite interactions. In this study, we aimed to identify the drivers potentially influencing host-bat fly interactions at different spatial scales (at the host, vegetation stand and landscape level), in a tropical anthropogenic landscape. For this purpose, we mist-netted phyllostomid and moormopid bats and collected the bat flies (streblids) parasitizing them in 10 sites representing secondary and old growth forest. In general, the variation in fly communities largely mirrored the variation in bat communities as a result of the high level of specialization characterizing host-bat fly interaction networks. Nevertheless, we observed that: (1) bats roosting dynamics can shape bat-streblid interactions, modulating parasite prevalence and the intensity of infestation; (2) a degraded matrix could favor crowding and consequently the exchange of ectoparasites among bat species, lessening the level of specialization of the interaction networks and promoting novel interactions; and (3) bat-fly interaction can also be shaped by the dilution effect, as a decrease in bat diversity could be associated with a potential increase in the dissemination and prevalence of streblids.

Anthropogenic factors and the risk of highly pathogenic avian influenza H5N1: prospects from a spatial-based model.

Science.gov (United States)

Paul, Mathilde; Tavornpanich, Saraya; Abrial, David; Gasqui, Patrick; Charras-Garrido, Myriam; Thanapongtharm, Weerapong; Xiao, Xiangming; Gilbert, Marius; Roger, Francois; Ducrot, Christian

2010-01-01

Beginning in 2003, highly pathogenic avian influenza (HPAI) H5N1 virus spread across Southeast Asia, causing unprecedented epidemics. Thailand was massively infected in 2004 and 2005 and continues today to experience sporadic outbreaks. While research findings suggest that the spread of HPAI H5N1 is influenced primarily by trade patterns, identifying the anthropogenic risk factors involved remains a challenge. In this study, we investigated which anthropogenic factors played a role in the risk of HPAI in Thailand using outbreak data from the "second wave" of the epidemic (3 July 2004 to 5 May 2005) in the country. We first performed a spatial analysis of the relative risk of HPAI H5N1 at the subdistrict level based on a hierarchical Bayesian model. We observed a strong spatial heterogeneity of the relative risk. We then tested a set of potential risk factors in a multivariable linear model. The results confirmed the role of free-grazing ducks and rice-cropping intensity but showed a weak association with fighting cock density. The results also revealed a set of anthropogenic factors significantly linked with the risk of HPAI. High risk was associated strongly with densely populated areas, short distances to a highway junction, and short distances to large cities. These findings highlight a new explanatory pattern for the risk of HPAI and indicate that, in addition to agro-environmental factors, anthropogenic factors play an important role in the spread of H5N1. To limit the spread of future outbreaks, efforts to control the movement of poultry products must be sustained. INRA, EDP Sciences, 2010.

Anthropogenic control on geomorphic process rates: can we slow down the erosion rates? (Geomorphology Outstanding Young Scientist Award & Penck Lecture)

Science.gov (United States)

Vanacker, V.

2012-04-01

The surface of the Earth is changing rapidly, largely in response to anthropogenic perturbation. Direct anthropogenic disturbance of natural environments may be much larger in many places than the (projected) indirect effects of climate change. There is now large evidence that humans have significantly altered geomorphic process rates, mainly through changes in vegetation composition, density and cover. While much attention has been given to the impact of vegetation degradation on geomorphic process rates, I suggest that the pathway of restoration is equally important to investigate. First, vegetation recovery after crop abandonment has a rapid and drastic impact on geomorphic process rates. Our data from degraded catchments in the tropical Andes show that erosion rates can be reduced by up to 100 times when increasing the protective vegetation cover. During vegetation restoration, the combined effects of the reduction in surface runoff, sediment production and hydrological connectivity are stronger than the individual effects together. Therefore, changes in erosion and sedimentation during restoration are not simply the reverse of those observed during degradation. Second, anthropogenic perturbation causes a profound but often temporary change in geomorphic process rates. Reconstruction of soil erosion rates in Spain shows us that modern erosion rates in well-vegetated areas are similar to long-term rates, despite evidence of strong pulses in historical erosion rates after vegetation clearance and agriculture. The soil vegetation system might be resilient to short pulses of accelerated erosion (and deposition), as there might exist a dynamic coupling between soil erosion and production also in degraded environments.

Free fatty acid profiling of marine sentinels by nanoLC-EI-MS for the assessment of environmental pollution effects.

Science.gov (United States)

Albergamo, Ambrogina; Rigano, Francesca; Purcaro, Giorgia; Mauceri, Angela; Fasulo, Salvatore; Mondello, Luigi

2016-11-15

The present work aims to elucidate the free fatty acid (FFA) profile of the mussel Mytilus galloprovincialis caged in an anthropogenically impacted area and in a reference site through an innovative and validated analytical approach for the assessment of biological alterations induced by marine pollution. The FFA pattern is involved in the regulation of different cellular pathways and differs with respect to metabolic stimuli. To this purpose, the lipid fraction of mussels coming from both sampling areas was extracted and the FFA fractions were isolated and purified by a solid phase extraction; then, nano-scale liquid chromatography coupled to electron ionization mass spectrometry (nanoLC-EI-MS) was employed for the characterization of the two samples. A total of 19 and 17 FFAs were reliably identified in the mussels coming from the reference and polluted site, respectively. Significant qualitative and quantitative differences found in saturated, monounsaturated and polyunsaturated species may be exploited as typical pollution biomarkers (e.g. alteration of the fatty acid biosynthetic system and lipotoxicity) and explain adverse and compromising effects (e.g. oxidative stress and inflammatory processes) related to environmental pollution. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluating natural and anthropogenic trace element inputs along an alpine to urban gradient in the Provo River, Utah, USA

International Nuclear Information System (INIS)

Carling, Gregory T.; Tingey, David G.; Fernandez, Diego P.; Nelson, Stephen T.; Aanderud, Zachary T.; Goodsell, Timothy H.; Chapman, Tucker R.

2015-01-01

Numerous natural and anthropogenic processes in a watershed produce the geochemical composition of a river, which can be altered over time by snowmelt and rainfall events and by built infrastructure (i.e., dams and diversions). Trace element concentrations coupled with isotopic ratios offer valuable insights to disentangle the effects of these processes on water quality. In this study, we measured a suite of 40+ trace and major elements (including As, Cd, Ce, Cr, Cs, Fe, La, Li, Mo, Pb, Rb, Sb, Se, Sr, Ti, Tl, U, and Zn), Sr isotopes ("8"7Sr/"8"6Sr), and stable isotopes of H and O (δD and δ"1"8O) to investigate natural and anthropogenic processes impacting the Provo River in northern Utah, USA. The river starts as a pristine mountain stream and passes through agricultural and urban areas, with two major reservoirs and several major diversions to and from the river. We sampled the entire 120 km length of the Provo River at 13 locations from the Uinta Mountains to Utah Valley, as well as two important tributaries, across the range of hydrologic conditions from low flow to snowmelt runoff during the 2013 water year. We also sampled the furthest downstream site in the Utah Valley urban area during a major flood event. Trace element concentrations indicate that a variety of factors potentially influence Provo River chemistry, including inputs from weathering of carbonate/siliciclastic rocks (Sr) and black shales (Se and U), geothermal groundwater (As, Cs, Li, and Rb), soil erosion during snowmelt runoff (Ce, Cr, Fe, La, Pb, and Ti), legacy mining operations (Mo, Sb, and Tl), and urban runoff (Cr, Pb, and Zn). Although specific elements overlap between different groups, the combination of different elements together with isotopic measurements and streamflow observations may act as diagnostic tools to identify sources. "8"7Sr/"8"6Sr ratios indicate a strong influence of siliciclastic bedrock in the headwaters with values exceeding 0.714 and carbonate bedrock in the

Impact of biogenic emission uncertainties on the simulated response of ozone and fine particulate matter to anthropogenic emission reductions.

Science.gov (United States)

Hogrefe, Christian; Isukapalli, Sastry S; Tang, Xiaogang; Georgopoulos, Panos G; He, Shan; Zalewsky, Eric E; Hao, Winston; Ku, Jia-Yeong; Key, Tonalee; Sistla, Gopal

2011-01-01

The role of emissions of volatile organic compounds and nitric oxide from biogenic sources is becoming increasingly important in regulatory air quality modeling as levels of anthropogenic emissions continue to decrease and stricter health-based air quality standards are being adopted. However, considerable uncertainties still exist in the current estimation methodologies for biogenic emissions. The impact of these uncertainties on ozone and fine particulate matter (PM2.5) levels for the eastern United States was studied, focusing on biogenic emissions estimates from two commonly used biogenic emission models, the Model of Emissions of Gases and Aerosols from Nature (MEGAN) and the Biogenic Emissions Inventory System (BEIS). Photochemical grid modeling simulations were performed for two scenarios: one reflecting present day conditions and the other reflecting a hypothetical future year with reductions in emissions of anthropogenic oxides of nitrogen (NOx). For ozone, the use of MEGAN emissions resulted in a higher ozone response to hypothetical anthropogenic NOx emission reductions compared with BEIS. Applying the current U.S. Environmental Protection Agency guidance on regulatory air quality modeling in conjunction with typical maximum ozone concentrations, the differences in estimated future year ozone design values (DVF) stemming from differences in biogenic emissions estimates were on the order of 4 parts per billion (ppb), corresponding to approximately 5% of the daily maximum 8-hr ozone National Ambient Air Quality Standard (NAAQS) of 75 ppb. For PM2.5, the differences were 0.1-0.25 microg/m3 in the summer total organic mass component of DVFs, corresponding to approximately 1-2% of the value of the annual PM2.5 NAAQS of 15 microg/m3. Spatial variations in the ozone and PM2.5 differences also reveal that the impacts of different biogenic emission estimates on ozone and PM2.5 levels are dependent on ambient levels of anthropogenic emissions.

A review of the major marine environmental concerns off the Canadian East Coast in the 1980s

International Nuclear Information System (INIS)

Harding, G.C.

1992-01-01

The natural environmental features of the Canadian east coast marine waters are described and anthropogenic influences that affect this environment are reviewed, with extensive reference to the literature. Effects from pollutants such as halogenated and aromatic hydrocarbons, trace metals, and radioactive materials are included, as well as effects from ozone depletion, greenhouse gas emissions, hydroelectric development, dredging and dumping, municipal sewage disposal, and coastal development in general. The most concentrated pollution in the Atlantic region is the St. Lawrence River valley and estuary, although there are a number of smaller sites associated with population centers such as St. John, New Brunswick and Halifax, Nova Scotia. Specific industries located along the coast have polluted local environments more than other activities. Sewage discharges have seriously affected expansion of the aquaculture industry. Hydroelectric development may have altered marine biological production, but more directed research is needed to assess the problem. Offshore exploration for oil and gas has had no observed adverse effects on the ecosystem to date, although the possibility for an environmental disaster from a well blowout or marine accident still exists. 177 refs., 3 figs

Polychaete richness and abundance enhanced in anthropogenically modified estuaries despite high concentrations of toxic contaminants.

Directory of Open Access Journals (Sweden)

Katherine A Dafforn

Full Text Available Ecological communities are increasingly exposed to multiple chemical and physical stressors, but distinguishing anthropogenic impacts from other environmental drivers remains challenging. Rarely are multiple stressors investigated in replicated studies over large spatial scales (>1000 kms or supported with manipulations that are necessary to interpret ecological patterns. We measured the composition of sediment infaunal communities in relation to anthropogenic and natural stressors at multiple sites within seven estuaries. We observed increases in the richness and abundance of polychaete worms in heavily modified estuaries with severe metal contamination, but no changes in the diversity or abundance of other taxa. Estuaries in which toxic contaminants were elevated also showed evidence of organic enrichment. We hypothesised that the observed response of polychaetes was not a 'positive' response to toxic contamination or a reduction in biotic competition, but due to high levels of nutrients in heavily modified estuaries driving productivity in the water column and enriching the sediment over large spatial scales. We deployed defaunated field-collected sediments from the surveyed estuaries in a small scale experiment, but observed no effects of sediment characteristics (toxic or enriching. Furthermore, invertebrate recruitment instead reflected the low diversity and abundance observed during field surveys of this relatively 'pristine' estuary. This suggests that differences observed in the survey are not a direct consequence of sediment characteristics (even severe metal contamination but are related to parameters that covary with estuary modification such as enhanced productivity from nutrient inputs and the diversity of the local species pool. This has implications for the interpretation of diversity measures in large-scale monitoring studies in which the observed patterns may be strongly influenced by many factors that covary with anthropogenic

Alterations of social interaction through genetic and environmental manipulation of the 22q11.2 gene Sept5 in the mouse brain.

Science.gov (United States)

Harper, Kathryn M; Hiramoto, Takeshi; Tanigaki, Kenji; Kang, Gina; Suzuki, Go; Trimble, William; Hiroi, Noboru

2012-08-01

Social behavior dysfunction is a symptomatic element of schizophrenia and autism spectrum disorder (ASD). Although altered activities in numerous brain regions are associated with defective social cognition and perception, the causative relationship between these altered activities and social cognition and perception-and their genetic underpinnings-are not known in humans. To address these issues, we took advantage of the link between hemizygous deletion of human chromosome 22q11.2 and high rates of social behavior dysfunction, schizophrenia and ASD. We genetically manipulated Sept5, a 22q11.2 gene, and evaluated its role in social interaction in mice. Sept5 deficiency, against a high degree of homogeneity in a congenic genetic background, selectively impaired active affiliative social interaction in mice. Conversely, virally guided overexpression of Sept5 in the hippocampus or, to a lesser extent, the amygdala elevated levels of active affiliative social interaction in C57BL/6J mice. Congenic knockout mice and mice overexpressing Sept5 in the hippocampus or amygdala were indistinguishable from control mice in novelty and olfactory responses, anxiety or motor activity. Moreover, post-weaning individual housing, an environmental condition designed to reduce stress in male mice, selectively raised levels of Sept5 protein in the amygdala and increased active affiliative social interaction in C57BL/6J mice. These findings identify this 22q11.2 gene in the hippocampus and amygdala as a determinant of social interaction and suggest that defective social interaction seen in 22q11.2-associated schizophrenia and ASD can be genetically and environmentally modified by altering this 22q11.2 gene.

On Dangerous Anthropogenic Interference and Climate Change Risk (Invited)

Science.gov (United States)

Mann, M. E.

2009-12-01

The United Nations Framework Convention on Climate Change (UNFCCC) commits signatory nations (which includes all major nations including the United States) to stabilizing greenhouse gas concentrations at levels short of Dangerous Anthropogenic Interference (“ DAI”) with the climate. To properly define DAI, one must take into account issues that are not only scientific, but, economic, political, and ethical in nature. Defining DAI is furthermore complicated by the inter-generational and regionally-disaggregated nature of the risks associated with climate change. In this talk, I will explore the nature of anthropogenic climate change risks and the notion of DAI.

Effects of anthropogenic aerosol particles on the radiation balance of the atmosphere. Einfluss anthropogener Aerosolteilchen auf den Strahlungshaushalt der Atmosphaere

Energy Technology Data Exchange (ETDEWEB)

Newiger, M

1985-01-01

The influence of aerosol particles is assessed on the basis of the changes in the climate parameters ''albedo'' and ''neutron flux''. Apart from the directly emitted particles, particles formed in the atmosphere as a result of SO/sub 2/ emissions are investigated. The model of aerosol effects on the radiation field takes account of the feedback with the microphysical parameters of the clouds. In the investigation, given particle concentrations were recalculated for three size classes using a two-dimensional transport model. The particle size distribution is described by a modified power function. Extreme-value estimates are made because the absorption capacity of anthropogenic particles is little known. A comparison of the climatic effects of anthropogenic activities shows that aerosol particles and SO/sub 2/ emissions have opposite effects on the radiation balance. (orig./PW).

Seasonal and mesoscale variability of oceanic transport of anthropogenic CO2

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J.-C. Dutay

2009-11-01

Full Text Available Estimates of the ocean's large-scale transport of anthropogenic CO2 are based on one-time hydrographic sections, but the temporal variability of this transport has not been investigated. The aim of this study is to evaluate how the seasonal and mesoscale variability affect data-based estimates of anthropogenic CO2 transport. To diagnose this variability, we made a global anthropogenic CO2 simulation using an eddy-permitting version of the coupled ocean sea-ice model ORCA-LIM. As for heat transport, the seasonally varying transport of anthropogenic CO2 is largest within 20° of the equator and shows secondary maxima in the subtropics. Ekman transport generally drives most of the seasonal variability, but the contribution of the vertical shear becomes important near the equator and in the Southern Ocean. Mesoscale variabilty contributes to the annual-mean transport of both heat and anthropogenic CO2 with strong poleward transport in the Southern Ocean and equatorward transport in the tropics. This "rectified" eddy transport is largely baroclinic in the tropics and barotropic in the Southern Ocean due to a larger contribution from standing eddies. Our analysis revealed that most previous hydrographic estimates of meridional transport of anthropogenic CO2 are severely biased because they neglect temporal fluctuations due to non-Ekman velocity variations. In each of the three major ocean basins, this bias is largest near the equator and in the high southern latitudes. In the subtropical North Atlantic, where most of the hydrographic-based estimates have been focused, this uncertainty represents up to 20% and 30% of total meridional transport of heat and CO2. Generally though, outside the tropics and Southern Ocean, there are only small variations in meridional transport due to seasonal variations in tracer fields and time variations in eddy transport. For the North Atlantic, eddy variability accounts for up to 10% and 15% of the total transport of

Resuspension. Decadal monitoring time series of the anthropogenic radioactivity deposition in Japan

International Nuclear Information System (INIS)

Igarashi, Yasuhito; Aoyama, Michio; Hirose, Katsumi; Miyao, Takashi; Nemoto, Kazuhiro; Tomita, Masatoshi; Fujikawa, Takashi

2003-01-01

Monthly atmospheric depositions of 90 Sr and 137 Cs have been observed at the Meteorological Research Institute (MRI), Tsukuba, Japan. This study reports temporal trends and levels of 90 Sr and 137 Cs depositions in the 1990s. Although the current 90 Sr and 137 Cs concentrations declined dramatically, they have been found continuously in the deposition samples throughout the 1990s. During this period, the annual 90 Sr ( 137 Cs) deposits at MRI ranged from 70-180 (140-350) mBq/m 2 /year. With a sufficiently long time series, the decreasing trend of the deposition evidently differs from the past stratospheric fallout; it is far slower. Thus, reservoirs other than the stratosphere provide small amounts of 90 Sr and 137 Cs to the atmosphere. A simple calculation clearly refutes the significance of the ocean as a potential source of airborne anthropogenic radioactivity. We will demonstrate that these radionuclides in the deposited materials originate from resuspension processes (soil dust suspension processes). The temporal trends of the time series monitoring reveal differences from those in the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) Report 2000, which were predicted by a model that disregarded resuspension. The specific activity of 90 Sr ( 137 Cs) in the annual depositions exhibited a 10-year (20-year) half-life. Those data were comparable with values reported in the literature for the half-residence time (HRT) of 90 Sr and 137 Cs in Japanese surface soils. They were also comparable to those calculated from nationwide data of 90 Sr and 137 Cs concentrations in the surface soil (0-10 cm) obtained from the Ministry of Education, Culture, Sports, Science and Technology Environmental Radiation Database (the MEXT Database). Regarding the activity ratio of 137 Cs/ 90 Sr, the Japanese nationwide surface soil data collected during the 1990s in the MEXT Database (median: 5.3, n=584) did not accord with that in the deposition samples

Biochemical parameters in the blood of grass snakes (Natrix natrix in ecosystems under varying degrees of anthropogenic influence

Directory of Open Access Journals (Sweden)

V. Y. Gasso

2016-09-01

Full Text Available The grass snake Natrix natrix (Linnaeus, 1758 is a partly hygrophilous species, distributed throughoutUkraine. This snake may be considered as a test object for environmental biomonitoring. Modern biochemical methods make it possible to obtain new scientific data on the effects of anthropogenic pressure on reptiles. Blood is a sensitive and informative indicator of the condition of an organism as it responds quickly to most changes in exogenous and endogenous factors, and reflects negative influences on both individual and, indirectly, populations. Changes in biochemical parameters may be used as biomarkers of the state of health of reptiles in ecosystems under varying degrees of anthropogenic pressure. Due the increase in anthropogenic influence the development and introduction of new methods of perceptual research, collection of up-to-date information and development of a database of reptile biochemical parameters have become an urgent priority. We collected mature individuals of the grass snake in floodplain ecosystems on the right bank of the Dnieper River in Dnipropetrovsk city. Grass snakes from floodplain habitats on the left bank of theSamaraRiver (O.L. Belgard Prysamarskii International Biosphere Station, Novomoskovsk district, Dnipropetrovsk province were studied as the control specimens. Our study demonstrated statistically significant differences between snakes from the study sites in the amount of albumin, urea and urea nitrogen, and inorganic phosphorus, as well as in alanine aminotransferase (ALT and alkaline phosphatise (AP activity. The amount of albumin in the blood serum of specimens from the anthropogenically transformed areas was significantly lower (by 25% than in that of the snakes caught in the control habitats. Decrease of the albumin concentration usually indicates abnormal processes in the kidneys and liver. According to the changes observed in the concentration of albumin, a corresponding increase in the albumin to

Anthropogenic heat fluxes over Moscow agglomeration and other Russian and world cities

Science.gov (United States)

Belova, Iya; Ginzburg, Alexander

2010-05-01

Urbanization, particularly with respect to its sustainability, remains to be a great challenge in all regions of the world. Urbanization has an influence on soils, hydrology, and climate, these changes have effect on global climate, pollution, increase of anthropogenic greenhouse gases in the earth's atmosphere and human health. Thus anthropogenic heat flux is an important factor for estimation of development of global climate. The simple formula for anthropogenic heat fluxes (AHF) was proposed in the EGU General Assembly 2008 presentation [1] AHF = k × PD × EC, were PD is urban population density and EC is total energy consumption per capita. It was estimated that two of the world megacities - Seoul and Moscow - have the highest AHF values - 83 and 56 W/m2 correspondently. In presented paper it was studied the reasons of such high anthropogenic heat fluxes within Moscow region as well as AHF over the major Russian cities. It was shown that main reason of this circumstance is the administrative divisions in Moscow region. Moscow is ringed by Moscow circle motor road. Accordingly the city has sharply defined boundaries and densely populated residential suburbs are cut off and don't included in Moscow city administrative area. It was constructed the special graph to illuminate why Moscow city has such a high anthropogenic heat factor and how much Moscow agglomeration AHF could be if consider not only Moscow city itself but also the nearest suburb towns. Using the data from World Bank [2] and Russian governmental statistic agency [3] anthropogenic heat fluxes for Russian cities with population more than 500 000 were estimated. Energy consumption data for different Russian regions were calculated by special routine using in the Web-atlas [4]. This research is supported by RAS Fundamental Research Project 'Influence of anthropogenic heat fluxes and aerosol pollution on heat balance and climate of urbanized areas'. Other results of this project is presented in paper [5

Anthropogenic climate change and allergen exposure: The role of plant biology.

Science.gov (United States)

Ziska, Lewis H; Beggs, Paul J

2012-01-01

Accumulation of anthropogenic gases, particularly CO(2), is likely to have 2 fundamental effects on plant biology. The first is an indirect effect through Earth's increasing average surface temperatures, with subsequent effects on other aspects of climate, such as rainfall and extreme weather events. The second is a direct effect caused by CO(2)-induced stimulation of photosynthesis and plant growth. Both effects are likely to alter a number of fundamental aspects of plant biology and human health, including aerobiology and allergic diseases, respectively. This review highlights the current and projected effect of increasing CO(2) and climate change in the context of plants and allergen exposure, emphasizing direct effects on plant physiologic parameters (eg, pollen production) and indirect effects (eg, fungal sporulation) related to diverse biotic and abiotic interactions. Overall, the review assumes that future global mitigation efforts will be limited and suggests a number of key research areas that will assist in adapting to the ongoing challenges to public health associated with increased allergen exposure. Published by Mosby, Inc.

Alteration of course in Danish energy- and environmental policy

International Nuclear Information System (INIS)

Trong, Maj Dang

2002-01-01

A new Danish government has announced great changes in Denmark's energy- and environmental policy. Norwegian hydro power may play a role in the government's consideration of a more efficient energy- and environmental policy. In principle, energy is to be produced where it is cheapest and least harmful to the environment. Green fees will be reorganized and billions will be saved by abolishing the subsidies to wind generators. The goal is to make wind energy self-supported by 2003. Plans for three new windmill parks in Danish waters have been abandoned. However, the environmental ministers of the countries around the North Sea agreed to speed up the development of ''green'' energy, not the least windmill parks at sea. The objective is that these oceanic windmill parks will contribute to reduced emission of carbon dioxide

Delivery of anthropogenic bioavailable iron from mineral dust and combustion aerosols to the ocean

OpenAIRE

伊藤, 彰記; 時, 宗波; ITO, Akinori; SHI, Zongbo

2016-01-01

Atmospheric deposition of anthropogenic soluble iron (Fe) to the ocean has been suggested to modulate primary ocean productivity and thus indirectly affect the climate. A key process contributing to anthropogenic sources of soluble Fe is associated with air pollution, which acidifies Fe-containing mineral aerosols during their transport and leads to Fe transformation from insoluble to soluble forms. However, there is large uncertainty in our estimate of this anthropogenic soluble Fe. In this ...

Controlling harmful cyanobacterial blooms in a world experiencing anthropogenic and climatic-induced change

International Nuclear Information System (INIS)

Paerl, Hans W.; Hall, Nathan S.; Calandrino, Elizabeth S.

2011-01-01

Harmful (toxic, food web altering, hypoxia generating) cyanobacterial algal blooms (CyanoHABs) are proliferating world-wide due to anthropogenic nutrient enrichment, and they represent a serious threat to the use and sustainability of our freshwater resources. Traditionally, phosphorus (P) input reductions have been prescribed to control CyanoHABs, because P limitation is widespread and some CyanoHABs can fix atmospheric nitrogen (N 2 ) to satisfy their nitrogen (N) requirements. However, eutrophying systems are increasingly plagued with non N 2 fixing CyanoHABs that are N and P co-limited or even N limited. In many of these systems N loads are increasing faster than P loads. Therefore N and P input constraints are likely needed for long-term CyanoHAB control in such systems. Climatic changes, specifically warming, increased vertical stratification, salinization, and intensification of storms and droughts play additional, interactive roles in modulating CyanoHAB frequency, intensity, geographic distribution and duration. In addition to having to consider reductions in N and P inputs, water quality managers are in dire need of effective tools to break the synergy between nutrient loading and hydrologic regimes made more favorable for CyanoHABs by climate change. The more promising of these tools make affected waters less hospitable for CyanoHABs by 1) altering the hydrology to enhance vertical mixing and/or flushing and 2) decreasing nutrient fluxes from organic rich sediments by physically removing the sediments or capping sediments with clay. Effective future CyanoHAB management approaches must incorporate both N and P loading dynamics within the context of altered thermal and hydrologic regimes associated with climate change. - Research Highlights: → Toxic cyanobacterial blooms (CyanoHABs) increasingly threaten global water supplies. → Human (nutrient) and climate (hydrology, temperature) changes synergistically promote CyanoHABs. → CyanoHAB control

Timing anthropogenic stressors to mitigate their impact on marine ecosystem resilience.

Science.gov (United States)

Wu, Paul Pao-Yen; Mengersen, Kerrie; McMahon, Kathryn; Kendrick, Gary A; Chartrand, Kathryn; York, Paul H; Rasheed, Michael A; Caley, M Julian

2017-11-02

Better mitigation of anthropogenic stressors on marine ecosystems is urgently needed to address increasing biodiversity losses worldwide. We explore opportunities for stressor mitigation using whole-of-systems modelling of ecological resilience, accounting for complex interactions between stressors, their timing and duration, background environmental conditions and biological processes. We then search for ecological windows, times when stressors minimally impact ecological resilience, defined here as risk, recovery and resistance. We show for 28 globally distributed seagrass meadows that stressor scheduling that exploits ecological windows for dredging campaigns can achieve up to a fourfold reduction in recovery time and 35% reduction in extinction risk. Although the timing and length of windows vary among sites to some degree, global trends indicate favourable windows in autumn and winter. Our results demonstrate that resilience is dynamic with respect to space, time and stressors, varying most strongly with: (i) the life history of the seagrass genus and (ii) the duration and timing of the impacting stress.

Satellite data based approach for the estimation of anthropogenic heat flux over urban areas

Science.gov (United States)

Nitis, Theodoros; Tsegas, George; Moussiopoulos, Nicolas; Gounaridis, Dimitrios; Bliziotis, Dimitrios

2017-09-01

Anthropogenic effects in urban areas influence the thermal conditions in the environment and cause an increase of the atmospheric temperature. The cities are sources of heat and pollution, affecting the thermal structure of the atmosphere above them which results to the urban heat island effect. In order to analyze the urban heat island mechanism, it is important to estimate the anthropogenic heat flux which has a considerable impact on the urban energy budget. The anthropogenic heat flux is the result of man-made activities (i.e. traffic, industrial processes, heating/cooling) and thermal releases from the human body. Many studies have underlined the importance of the Anthropogenic Heat Flux to the calculation of the urban energy budget and subsequently, the estimation of mesoscale meteorological fields over urban areas. Therefore, spatially disaggregated anthropogenic heat flux data, at local and city scales, are of major importance for mesoscale meteorological models. The main objectives of the present work are to improve the quality of such data used as input for mesoscale meteorological models simulations and to enhance the application potential of GIS and remote sensing in the fields of climatology and meteorology. For this reason, the Urban Energy Budget concept is proposed as the foundation for an accurate determination of the anthropogenic heat discharge as a residual term in the surface energy balance. The methodology is applied to the cities of Athens and Paris using the Landsat ETM+ remote sensing data. The results will help to improve our knowledge on Anthropogenic Heat Flux, while the potential for further improvement of the methodology is also discussed.

Effect of coupled anthropogenic perturbations on stratospheric ozone

International Nuclear Information System (INIS)

Wuebbles, D.J.; Luther, F.M.; Penner, J.E.

1992-01-01

Since 1976 the greatest concern about potential perturbations to stratospheric ozone has been in regard to the atmospheric release of chlorofluorocarbons. Consequently, atmospheric measurements of ozone have usually been compared with model calculations in which only chlorocarbon perturbations are considered. However, in order to compare theoretical calculations with recent measurements of ozone and to project expected changes to atmospheric ozone levels over the next few decades, one must consider the effect from other perturbations as well. In this paper, the authors consider the coupling between several possible anthropogenic atmospheric perturbations. Namely, they examine the effects of past and possible future increases of chlorocarbons, CO 2 , N 2 O, and NO x . The focus of these calculations is on the potential changes in ozone due to chlorocarbon emissions, how other anthropogenic perturbations may have influenced the actual change in ozone over the last decade, and how these perturbations may influence future changes in ozone. Although calculations including future chlorocarbon emissions alone result in significant reductions in ozone, there is very little change in total ozone over the coming decades when other anthropogenic sources are included. Increasing CO 2 concentrations have the largest offsetting effect on the change in total ozone due to chlorocarbons. Owing to the necessity of considering emissions from a number of trace gases simultaneously, determining expected global-scale chemical and climatic effects is more complex than was previously recognized

Impact of anthropogenic climate change and human activities on environment and ecosystem services in arid regions.

Science.gov (United States)

Mahmoud, Shereif H; Gan, Thian Y

2018-08-15

The implications of anthropogenic climate change, human activities and land use change (LUC) on the environment and ecosystem services in the coastal regions of Saudi Arabia were analyzed. Earth observations data was used to drive land use categories between 1970 and 2014. Next, a Markov-CA model was developed to characterize the dynamic of LUC between 2014 and 2100 and their impacts on regions' climate and environment. Non-parametric change point and trend detection algorithms were applied to temperature, precipitation and greenhouse gases data to investigate the presence of anthropogenic climate change. Lastly, climate models were used to project future climate change between 2014 and 2100. The analysis of LUC revealed that between 1970 and 2014, built up areas experienced the greatest growth during the study period, leading to a significant monotonic trend. Urban areas increased by 2349.61km 2 between 1970 and 2014, an average increase of >53.4km 2 /yr. The projected LUC between 2014 and 2100 indicate a continued increase in urban areas and irrigated cropland. Human alteration of land use from natural vegetation and forests to other uses after 1970, resulted in a loss, degradation, and fragmentation, all of which usually have devastating effects on the biodiversity of the region. Resulting in a statistically significant change point in temperature anomaly after 1968 with a warming trend of 0.24°C/decade and a downward trend in precipitation anomaly of 12.2mm/decade. Total greenhouse gas emissions including all anthropogenic sources showed a statistically significant positive trend of 78,090Kt/decade after 1991. This is reflected in the future projection of temperature anomaly between 1900 and 2100 with a future warming trend of 0.19°C/decade. In conclusion, human activities, industrial revelation, deforestation, land use transformation and increase in greenhouse gases had significant implications on the environment and ecosystem services of the study area

Identifying the driving forces of urban expansion and its environmental impact in Jakarta-Bandung mega urban region

Science.gov (United States)

Pravitasari, A. E.; Rustiadi, E.; Mulya, S. P.; Setiawan, Y.; Fuadina, L. N.; Murtadho, A.

2018-05-01

The socio-economic development in Jakarta-Bandung Mega Urban Region (JBMUR) caused the increasing of urban expansion and led to a variety of environmental damage such as uncontrolled land use conversion and raising anthropogenic disaster. The objectives of this study are: (1) to identify the driving forces of urban expansion that occurs on JBMUR and (2) to analyze the environmental quality decline on JBMUR by producing time series spatial distribution map and spatial autocorrelation of floods and landslide as the proxy of anthropogenic disaster. The driving forces of urban expansion in this study were identified by employing Geographically Weighted Regression (GWR) model using 6 (six) independent variables, namely: population density, percentage of agricultural land, distance to the center of capital city/municipality, percentage of household who works in agricultural sector, distance to the provincial road, and distance to the local road. The GWR results showed that local demographic, social and economic factors including distance to the road spatially affect urban expansion in JBMUR. The time series spatial distribution map of floods and landslide event showed the spatial cluster of anthropogenic disaster in some areas. Through Local Moran Index, we found that environmental damage in one location has a significant impact on the condition of its surrounding area.

Comparative bacterial community analysis in relatively pristine and anthropogenically influenced mangrove ecosystems on the Red Sea.

Science.gov (United States)

Ullah, Riaz; Yasir, Muhammad; Khan, Imran; Bibi, Fehmida; Sohrab, Sayed Sartaj; Al-Ansari, Ahmed; Al-Abbasi, Fahad; Al-Sofyani, Abdulmohsin A; Daur, Ihsanullah; Lee, Seon-Woo; Azhar, Esam I

2017-08-01

Mangrove habitats are ecologically important ecosystems that are under severe pressure worldwide because of environmental changes and human activities. In this study, 16S rRNA gene amplicon deep-sequencing was used to compare bacterial communities in Red Sea mangrove ecosystems at anthropogenically influenced coastal sites with those at a relatively pristine island site. In total, 32 phyla were identified from the mangrove rhizospheres, with Proteobacteria predominating at each of the studied sites; however, the relative abundance was significantly decreased at the coastal sites (Mastorah, MG-MS; Ar-Rayis, MG-AR) compared with the pristine island site near Dhahban (MG-DBI). The phyla Actinobacteria, Firmicutes, Acidobacteria, Chloroflexi, Spirochetes, and Planctomycetes were present at a relative abundance of >1% at the MG-MS and MG-AR sites, but their concentration was <1% at the MG-DBI site. A total of 1659 operational taxonomic units (OTUs) were identified at the species level, and approximately 945 OTUs were shared across the different sampling sites. Multivariate principal coordinate data analysis separated the MG-DBI site from the MG-AR and MG-MS cluster. Specific bacterial taxa were enriched at each location, and in particular, the genera Pseudoalteromonas and Cobetia were predominantly identified in the MG-DBI site compared with the anthropogenically influenced coastal sites.

Spatial-temporal eco-environmental vulnerability assessment and its influential factors based on Landsat data

Science.gov (United States)

Anh, N. K.; Liou, Y. A.; Ming-Hsu, L.

2016-12-01

Regional land use/land cover (LULC) changes lead to various changes in ecological processes and, in turn, alter regional micro-climate. To understand eco-environmental responses to LULC changes, eco-environmental evaluation is thus required with aims to identify vulnerable regions and influential factors, so that practical measures for environmental protection and management may be proposed. The Thua Thien - Hue Province has been experiencing urbanization at a rapid rate in both population and physical size. The urban land, agricultural land, and aquaculture activities have been invasively into natural space and caused eco-environment deterioration by land desertification, soil erosion, shrinking forest resources,…etc. In this study, an assessment framework that is composed by 11 variables with 9 of them constructed from Landsat time series is proposed to serve as basis to examine eco-environmental vulnerability in the Thua Thien - Hue Province in years 1989, 2003, and 2014. An eco-environmental vulnerability map is assorted into six vulnerability levels consisting of potential, slight, light, medium, heavy, and very heavy vulnerabilities. Result shows that there is an increasing trend in eco-environmental vulnerability in general with expected evolving distributions in heavy and very heavy vulnerability levels, which mainly lying on developed land, bare land, semi bare land, agricultural land, and poor and recovery forests. In contrast, there is a significant decline in potential vulnerability level. The contributing factors of an upward trend in medium, heavy, and very heavy levels include: (i) a large natural forest converted to plantation forest and agriculture land; and (ii) significant expansion of developed land leading to difference in thermal signatures in urban areas as compared with those of the surrounding areas. It is concluded that anthropogenic processes with transformation on LULC has amplified the vulnerability of eco-environment in the study

Environmental accounting on a communal level: A tool to support environmental management and decision-making by communal executives.

Science.gov (United States)

Kröger, G; Pietsch, J; Ufermann, K

1999-01-01

Starting from an ecological perspective of urban-industrial areas, environmental accounting is used to analyse and to evaluate which environmental impacts are the result of communal activities (e.g. the results of different kinds of water supply systems). Therefore, the anthropogenic fluxes, the changing quality of areas as well as the processes between the environmental fields are taken into account. The approach is based on methodical elements of te Life Cycle Analysis and the Environmental Impact Assessment. Looking at the 'urban systems' within the communal activities, 'ecological modelling' gives us a new and fuller picture of the spatial and temporal character of urban metabolism. The approach supports the perception of cumulative effects and the postponement of environmental problems and opens new horizons for process-oriented environmental planning within the community. Greater efficiency and a decrease in costs can be arrived at by leaving 'end of the pipe' strategies; opportunities for a better planning process and measures for different individuals and organisations can be drawn up. A data base which acts as a 'support system' implements the computer-aided approach to environmental accounting.

Immune activity, body condition and human-associated environmental impacts in a wild marine mammal.

Directory of Open Access Journals (Sweden)

Patrick M Brock

Full Text Available Within individuals, immunity may compete with other life history traits for resources, such as energy and protein, and the damage caused by immunopathology can sometimes outweigh the protective benefits that immune responses confer. However, our understanding of the costs of immunity in the wild and how they relate to the myriad energetic demands on free-ranging organisms is limited. The endangered Galapagos sea lion (Zalophus wollebaeki is threatened simultaneously by disease from domestic animals and rapid changes in food availability driven by unpredictable environmental variation. We made use of this unique ecology to investigate the relationship between changes in immune activity and changes in body condition. We found that during the first three months of life, changes in antibody concentration were negatively correlated with changes in mass per unit length, skinfold thickness and serum albumin concentration, but only in a sea lion colony exposed to anthropogenic environmental impacts. It has previously been shown that changes in antibody concentration during early Galapagos sea lion development were higher in a colony exposed to anthropogenic environmental impacts than in a control colony. This study allows for the possibility that these relatively large changes in antibody concentration are associated with negative impacts on fitness through an effect on body condition. Our findings suggest that energy availability and the degree of plasticity in immune investment may influence disease risk in natural populations synergistically, through a trade-off between investment in immunity and resistance to starvation. The relative benefits of such investments may change quickly and unpredictably, which allows for the possibility that individuals fine-tune their investment strategies in response to changes in environmental conditions. In addition, our results suggest that anthropogenic environmental impacts may impose subtle energetic costs on

Stream vulnerability to widespread and emergent stressors: a focus on unconventional oil and gas

Science.gov (United States)

Entrekin, Sally; Maloney, Kelly O.; Katherine E. Kapo,; Walters, Annika W.; Evans-White, Michelle A.; Klemow, Kenneth M.

2015-01-01

Multiple stressors threaten stream physical and biological quality, including elevated nutrients and other contaminants, riparian and in-stream habitat degradation and altered natural flow regime. Unconventional oil and gas (UOG) development is one emerging stressor that spans the U.S. UOG development could alter stream sedimentation, riparian extent and composition, in-stream flow, and water quality. We developed indices to describe the watershed sensitivity and exposure to natural and anthropogenic disturbances and computed a vulnerability index from these two scores across stream catchments in six productive shale plays. We predicted that catchment vulnerability scores would vary across plays due to climatic, geologic and anthropogenic differences. Across-shale averages supported this prediction revealing differences in catchment sensitivity, exposure, and vulnerability scores that resulted from different natural and anthropogenic environmental conditions. For example, semi-arid Western shale play catchments (Mowry, Hilliard, and Bakken) tended to be more sensitive to stressors due to low annual average precipitation and extensive grassland. Catchments in the Barnett and Marcellus-Utica were naturally sensitive from more erosive soils and steeper catchment slopes, but these catchments also experienced areas with greater UOG densities and urbanization. Our analysis suggested Fayetteville and Barnett catchments were vulnerable due to existing anthropogenic exposure. However, all shale plays had catchments that spanned a wide vulnerability gradient. Our results identify vulnerable catchments that can help prioritize stream protection and monitoring efforts. Resource managers can also use these findings to guide local development activities to help reduce possible environmental effects.

Stream Vulnerability to Widespread and Emergent Stressors: A Focus on Unconventional Oil and Gas.

Science.gov (United States)

Entrekin, Sally A; Maloney, Kelly O; Kapo, Katherine E; Walters, Annika W; Evans-White, Michelle A; Klemow, Kenneth M

2015-01-01

Multiple stressors threaten stream physical and biological quality, including elevated nutrients and other contaminants, riparian and in-stream habitat degradation and altered natural flow regime. Unconventional oil and gas (UOG) development is one emerging stressor that spans the U.S. UOG development could alter stream sedimentation, riparian extent and composition, in-stream flow, and water quality. We developed indices to describe the watershed sensitivity and exposure to natural and anthropogenic disturbances and computed a vulnerability index from these two scores across stream catchments in six productive shale plays. We predicted that catchment vulnerability scores would vary across plays due to climatic, geologic and anthropogenic differences. Across-shale averages supported this prediction revealing differences in catchment sensitivity, exposure, and vulnerability scores that resulted from different natural and anthropogenic environmental conditions. For example, semi-arid Western shale play catchments (Mowry, Hilliard, and Bakken) tended to be more sensitive to stressors due to low annual average precipitation and extensive grassland. Catchments in the Barnett and Marcellus-Utica were naturally sensitive from more erosive soils and steeper catchment slopes, but these catchments also experienced areas with greater UOG densities and urbanization. Our analysis suggested Fayetteville and Barnett catchments were vulnerable due to existing anthropogenic exposure. However, all shale plays had catchments that spanned a wide vulnerability gradient. Our results identify vulnerable catchments that can help prioritize stream protection and monitoring efforts. Resource managers can also use these findings to guide local development activities to help reduce possible environmental effects.

The anthropogenic influence on heat and humidity in the US Midwest

Science.gov (United States)

Inda Diaz, H. A.; O'Brien, T. A.; Stone, D. A.

2016-12-01

Heatwaves, and extreme temperatures in general, have a wide range of negative impacts on society, and particularly on human health. In addition to temperature, humidity plays a key role in regulating human body temperature, with higher humidities tending to reduce the effectiveness of perspiration. There is recent theoretical and observational evidence that co-occurring extreme heat and humidity can potentially have a much more dramatic impact on human health than either extreme in isolation. There is an abundance of observational evidence indicating that anthropogenic increases in greenhouse gas (GHG) forcing have contributed to an increase in the intensity and frequency of temperature extremes on a global scale. However, aside from purely thermodynamically-driven increases in near-surface humidity, there is a paucity of similar evidence for anthropogenic impacts on humidity. Thermodynamic scaling would suggest that air masses originating from the ocean would be associated with higher specific humidity in a warmer world, and transpiration from irrigated crops could further increase humidity in warm air masses. In order to explore the role of anthropogenic GHG forcing on the co-occurrence of temperature and humidity extremes in the Midwestern United States (US), we evaluate a large ensemble of global climate model simulations with and without anthropogenic GHG forcing. In particular, we examine differences between the probability distributions of near-surface temperature, humidity, wet-bulb temperature, and the joint distribution of temperature and humidity in this ensemble. Finally, we explore augmenting this experimental framework with additional simulations to explore the role of anthropogenic changes in the land surface, and in particular irrigated crops, on co-occurring extreme heat and humidity.

Combustion of environmentally altered molybdenum trioxide nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Moore, Kevin; Pantoya, Michelle L. [Mechanical Engineering Department, Texas Tech University, 2500 Broadway, Lubbock, TX 79409 (United States)

2006-06-15

Nanocomposite thermite mixtures are currently under development for many primer applications due to their high energy densities, high ignition sensitivity, and low release of toxins into the environment. However, variability and inconsistencies in combustion performance have not been sufficiently investigated. Environmental interactions with the reactants are thought to be a contributing factor to these variabilities. Combustion velocity experiments were conducted on aluminum (Al) and molybdenum trioxide (MoO{sub 3}) mixtures to investigate the role of environmental interactions such as light exposure and humidity. While the Al particles were maintained in an ambient, constant environment, the MoO{sub 3} particles were exposed to UV or fluorescent light, and highly humid environments. Results show that UV and fluorescent lighting over a period of days does not significantly contribute to performance deterioration. However, a humid environment severely decreases combustion performance if the oxidizer particles are not heat-treated. Heat treatment of the MoO{sub 3} greatly increases the material's ability to resist water absorption, yielding more repeatable combustion performance. This work further quantifies the role of the environment in the decrease of combustion performance of nanocomposites over time. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

Human disturbance alters endocrine and immune responses in the Galapagos marine iguana (Amblyrhynchus cristatus).

Science.gov (United States)

French, Susannah S; DeNardo, Dale F; Greives, Timothy J; Strand, Christine R; Demas, Gregory E

2010-11-01

Anthropogenic disturbance is a relevant and widespread facilitator of environmental change and there is clear evidence that it impacts natural populations. While population-level responses to major anthropogenic changes have been well studied, individual physiological responses to mild disturbance can be equally critical to the long-term survival of a species, yet they remain largely unexamined. The current study investigated the impact of seemingly low-level anthropogenic disturbance (ecotourism) on stress responsiveness and specific fitness-related immune measures in different breeding stages of the marine iguana (Amblyrhynchus cristatus). Specifically, we found stress-induced elevations in plasma corticosterone among tourist-exposed populations relative to undisturbed populations. We also found changes in multiple immunological responses associated with stress-related effects of human disturbance, including bacterial killing ability, cutaneous wound healing, and hemolytic complement activity, and the responses varied according to reproductive state. By identifying health-related consequences of human disturbance, this study provides critical insight into the conservation of a well-known species that has a very distinct ecology. The study also broadens the foundation of knowledge needed to understand the global significance of various levels of human disturbance. Copyright © 2010 Elsevier Inc. All rights reserved.

Human disturbance alters endocrine and immune responses in the Galapagos marine iguana (Amblyrhynchus cristatus)

Science.gov (United States)

French, Susannah S; DeNardo, Dale F.; Greives, Timothy J.; Strand, Christine R.; Demas, Gregory E.

2010-01-01

Anthropogenic disturbance is a relevant and widespread facilitator of environmental change and there is clear evidence that it impacts natural populations. While population-level responses to major anthropogenic changes have been well studied, individual physiological responses to mild disturbance can be equally critical to the long-term survival of a species, yet they remain largely unexamined. The current study investigated the impact of seemingly low-level anthropogenic disturbance (ecotourism) on stress responsiveness and specific fitness-related immune measures in different breeding stages of the marine iguana (Amblyrhynchus cristatus). Specifically, we found stress-induced elevations in plasma corticosterone among tourist-exposed populations relative to undisturbed populations. We also found changes in multiple immunological responses associated with stress-related effects of human disturbance, including bacterial killing ability, cutaneous wound healing, and hemolytic complement activity, and the responses varied according to reproductive state. By identifying health-related consequences of human disturbance, this study provides critical insight into the conservation of a well-known species that has a very distinct ecology. The study also broadens the foundation of knowledge needed to understand the global significance of various levels of human disturbance. PMID:20708010

The impact of anthropogenic and biogenic emissions on surface ozone concentrations in Istanbul.

Science.gov (United States)

Im, Ulas; Poupkou, Anastasia; Incecik, Selahattin; Markakis, Konstantinos; Kindap, Tayfun; Unal, Alper; Melas, Dimitros; Yenigun, Orhan; Topcu, Sema; Odman, M Talat; Tayanc, Mete; Guler, Meltem

2011-03-01

Surface ozone concentrations at Istanbul during a summer episode in June 2008 were simulated using a high resolution and urban scale modeling system coupling MM5 and CMAQ models with a recently developed anthropogenic emission inventory for the region. Two sets of base runs were performed in order to investigate for the first time the impact of biogenic emissions on ozone concentrations in the Greater Istanbul Area (GIA). The first simulation was performed using only the anthropogenic emissions whereas the second simulation was performed using both anthropogenic and biogenic emissions. Biogenic NMVOC emissions were comparable with anthropogenic NMVOC emissions in terms of magnitude. The inclusion of biogenic emissions significantly improved the performance of the model, particularly in reproducing the low night time values as well as the temporal variation of ozone concentrations. Terpene emissions contributed significantly to the destruction of the ozone during nighttime. Biogenic NMVOCs emissions enhanced ozone concentrations in the downwind regions of GIA up to 25ppb. The VOC/NO(x) ratio almost doubled due to the addition of biogenic NMVOCs. Anthropogenic NO(x) and NMVOCs were perturbed by ±30% in another set of simulations to quantify the sensitivity of ozone concentrations to the precursor emissions in the region. The sensitivity runs, as along with the model-calculated ozone-to-reactive nitrogen ratios, pointed NO(x)-sensitive chemistry, particularly in the downwind areas. On the other hand, urban parts of the city responded more to changes in NO(x) due to very high anthropogenic emissions. Copyright © 2010 Elsevier B.V. All rights reserved.

Anthropogenic radiofrequency electromagnetic fields as an emerging threat to wildlife orientation

International Nuclear Information System (INIS)

Balmori, Alfonso

2015-01-01

The rate of scientific activity regarding the effects of anthropogenic electromagnetic radiation in the radiofrequency (RF) range on animals and plants has been small despite the fact that this topic is relevant to the fields of experimental biology, ecology and conservation due to its remarkable expansion over the past 20 years. Current evidence indicates that exposure at levels that are found in the environment (in urban areas and near base stations) may particularly alter the receptor organs to orient in the magnetic field of the earth. These results could have important implications for migratory birds and insects, especially in urban areas, but could also apply to birds and insects in natural and protected areas where there are powerful base station emitters of radiofrequencies. Therefore, more research on the effects of electromagnetic radiation in nature is needed to investigate this emerging threat. - Highlights: • The growth of wireless telecommunication technologies causes increased electrosmog. • Radio frequency fields in the MHz range disrupt insect and bird orientation. • Radio frequency noise interferes with the primary process of magnetoreception. • Existing guidelines do not adequately protect wildlife. • Further research in this area is urgent

Anthropogenic radiofrequency electromagnetic fields as an emerging threat to wildlife orientation

Energy Technology Data Exchange (ETDEWEB)

Balmori, Alfonso, E-mail: balmaral@jcyl.es

2015-06-15

The rate of scientific activity regarding the effects of anthropogenic electromagnetic radiation in the radiofrequency (RF) range on animals and plants has been small despite the fact that this topic is relevant to the fields of experimental biology, ecology and conservation due to its remarkable expansion over the past 20 years. Current evidence indicates that exposure at levels that are found in the environment (in urban areas and near base stations) may particularly alter the receptor organs to orient in the magnetic field of the earth. These results could have important implications for migratory birds and insects, especially in urban areas, but could also apply to birds and insects in natural and protected areas where there are powerful base station emitters of radiofrequencies. Therefore, more research on the effects of electromagnetic radiation in nature is needed to investigate this emerging threat. - Highlights: • The growth of wireless telecommunication technologies causes increased electrosmog. • Radio frequency fields in the MHz range disrupt insect and bird orientation. • Radio frequency noise interferes with the primary process of magnetoreception. • Existing guidelines do not adequately protect wildlife. • Further research in this area is urgent.

A general exergy-based environmental impact index

International Nuclear Information System (INIS)

Diaz-Mendez, Sosimo E.; Rodriguez-Lelis, Jose Maria; Hernandez-Guerrero, Abel

2011-01-01

An ecosystem is a complex system in which biotic and abiotic factors interact and influence each other both directly and indirectly. Each of these factors has to comply with a specific function in the different processes that occur inside the ecosystem, whether transporting or transforming energy or both. When anthropogenic emissions are produced, part of the useful energy of the ecosystem is used to assimilate or absorb those emissions, and the energy spent, loses its function and becomes lost work in accordance with the Gouy-Stodola theorem. Thus, the work that an ecosystem can carry out varies as a function of the lost work produced by anthropogenic sources. The permanency or loss of the ecosystem depends on how many irreversibilities it can support. The second law of thermodynamics through a systematic use of the exergy and lost work is the basis of this paper where a general environmental impact index, based on exergy, is proposed. For the purpose of this work, the ecosystem is divided in subsystems--water, soil, atmosphere, organisms and society- -all of them inter-related. The ideal work variation can be obtained from each subsystem within the selected ecosystem, and a global index can be determined by adding the partial lost work of each subsystem. This global index is then used to determine the trend followed by the ecosystem from its pristine, original or environmental line base state. This environmental impact index applicability is presented for a simple combustion example

Anthropogenic host plant expansion leads a nettle-feeding butterfly out of the forest: consequences for larval survival and developmental plasticity in adult morphology.

Science.gov (United States)

Merckx, Thomas; Serruys, Mélanie; Van Dyck, Hans

2015-04-01

Recent anthropogenic eutrophication has meant that host plants of nettle-feeding insects became quasi-omnipresent in fertile regions of Western Europe. However, host plant resource quality - in terms of microclimate and nutritional value - may vary considerably between the 'original' forest habitat and 'recent' agricultural habitat. Here, we compared development in both environmental settings using a split-brood design, so as to explore to what extent larval survival and adult morphology in the nettle-feeding butterfly Aglais urticae are influenced by the anthropogenic environment. Nettles along field margins had higher C/N ratios and provided warmer microclimates to larvae. Larvae developed 20% faster and tended to improve their survival rates, on the agricultural land compared to woodland. Our split-brood approach indicated plastic responses within families, but also family effects in the phenotypic responses. Adult males and females had darker wing pigmentation in the drier and warmer agricultural environment, which contrasts with the thermal melanism hypothesis. Developmental plasticity in response to this microclimatically different and more variable habitat was associated with a broader phenotypic parameter space for the species. Both habitat expansion and developmental plasticity are likely contributors to the ecological and evolutionary success of these nettle-feeding insects in anthropogenic environments under high nitrogen load.

Environmental tasks of anthropogenic actions and climatic changes in pozo del Molle, Cordoba Argentina

International Nuclear Information System (INIS)

Mansilla, L.; Karlsson, A.; Ayala, R.

2007-01-01

This work was made in Pozo del Molle town, Rio Segundo, Cordoba. Argentina. The human impact added to climate changes, mainly the increase of precipitations, affects negatively in the environmental problems. In the area, in the last years, the problems that lead to the degradation of the environment were accentuated. The disposition of the final waste disposal has been determined through the following studies: analysis of the geological conditions of the area, consideration of the climatic situation, and the elevation and contamination the phreatic. Also an analysis about the rate of the habitant/day solid residual generation, the distance between the site where is located the urban solid residues and the town, the predominant winds and the vulnerability of the phreatic, which represents the greatest problem of the area, was made. It has been established the alternatives to carry out an appropriate environmental administration. Key words: human impact, climatic changes, environmental problems, phreatic, Pozo del Molle (Argentina). (author)

Mapping 1995 global anthropogenic emissions of mercury

NARCIS (Netherlands)

Pacyna, Jozef M.; Pacyna, Elisabeth G.; Steenhuisen, Frits; Wilson, Simon

2003-01-01

This paper presents maps of anthropogenic Hg emissions worldwide within a 1degrees x 1degrees latitude/longitude grid system in 1995. As such, the paper is designed for modelers simulating the Hg transport within air masses and Hg deposition to aquatic and terrestrial ecosystems. Maps of total Hg

Environmental stressors alter relationships between physiology and behaviour.

Science.gov (United States)

Killen, Shaun S; Marras, Stefano; Metcalfe, Neil B; McKenzie, David J; Domenici, Paolo

2013-11-01

Although correlations have frequently been observed between specific physiological and behavioural traits across a range of animal taxa, the nature of these associations has been shown to vary. Here we argue that a major source of this inconsistency is the influence of environmental stressors, which seem capable of revealing, masking, or modulating covariation in physiological and behavioural traits. These effects appear to be mediated by changes in the observed variation of traits and differential sensitivity to stressors among phenotypes. Considering that wild animals routinely face a range of biotic and abiotic stressors, increased knowledge of these effects is imperative for understanding the causal mechanisms of a range of ecological phenomena and evolutionary responses to stressors associated with environmental change. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

A Model for Developing and Assessing Youth-Based Environmental Engagement Programmes

Science.gov (United States)

Riemer, Manuel; Lynes, Jennifer; Hickman, Gina

2014-01-01

In this paper, we argue that a fundamental cultural shift is needed to effectively address anthropogenic causes of climate change. Evidence suggests that youth are well positioned to create such transformation. While various studies have contributed empirical evidence to numerous youth-based non-formal environmental engagement programmes, what is…

The pattern of anthropogenic signal emergence in Greenland Ice Sheet surface mass balance

NARCIS (Netherlands)

Fyke, J.G.; Vizcaino, M.; Lipscomb, W.H.

2014-01-01

Surface mass balance (SMB) trends influence observed Greenland Ice Sheet (GrIS) mass loss, but the component of these trends related to anthropogenic forcing is unclear. Here we study the simulated spatial pattern of emergence of an anthropogenically derived GrIS SMB signal between 1850 and 2100

Solar radiation and tidal exposure as environmental drivers of Enhalus acoroides dominated seagrass meadows.

Directory of Open Access Journals (Sweden)

Richard K F Unsworth

Full Text Available There is strong evidence of a global long-term decline in seagrass meadows that is widely attributed to anthropogenic activity. Yet in many regions, attributing these changes to actual activities is difficult, as there exists limited understanding of the natural processes that can influence these valuable ecosystem service providers. Being able to separate natural from anthropogenic causes of seagrass change is important for developing strategies that effectively mitigate and manage anthropogenic impacts on seagrass, and promote coastal ecosystems resilient to future environmental change. The present study investigated the influence of environmental and climate related factors on seagrass biomass in a large ≈250 ha meadow in tropical north east Australia. Annual monitoring of the intertidal Enhalus acoroides (L.f. Royle seagrass meadow over eleven years revealed a declining trend in above-ground biomass (54% significant overall reduction from 2000 to 2010. Partial Least Squares Regression found this reduction to be significantly and negatively correlated with tidal exposure, and significantly and negatively correlated with the amount of solar radiation. This study documents how natural long-term tidal variability can influence long-term seagrass dynamics. Exposure to desiccation, high UV, and daytime temperature regimes are discussed as the likely mechanisms for the action of these factors in causing this decline. The results emphasise the importance of understanding and assessing natural environmentally-driven change when interpreting the results of seagrass monitoring programs.

Past and Future of the Anthropogenic Biosphere

Science.gov (United States)

Ellis, E. C.

2010-12-01

Human populations and their use of land have now transformed most of the terrestrial biosphere into anthropogenic biomes (anthromes). As anthromes have emerged as the dominant global forms of ecological pattern and process, human interactions with terrestrial ecosystems have become a key earth system process, determining the structure and functioning of the biosphere. This presentation explores Ester Boserup’s land use intensification theories as models for understanding the emergence and dynamics of anthromes and their ecological processes, including their biogeochemistry and community structure, from the mostly wild biosphere of the Holocene to the primarily anthropogenic biosphere of the present and future. Existing global models and data for human population growth and land use over the Holocene differ in their portrayal of the global transition to a mostly anthropogenic biosphere. Yet there is little doubt that human populations have continued to grow over the long term and that anthromes have been increasingly important global ecological systems for millennia. This is conclusive evidence that human interactions with ecosystems can be sustained over the long-term, albeit under conditions that may no longer be realizable by either Earth or human systems. The classic Malthusian paradigm, in which human population growth outstrips natural resources leading to population collapse is unsupported by historical observations at global scale. Boserupian intensification is the better model, providing a robust theoretical foundation in which socio-ecological systems evolve as human populations increase, towards increasingly efficient use of limiting natural resources and enhanced production of anthropogenic ecological services such as food. This is not a story of technical advance, but rather of the forced adoption of ever more energy-intensive technical solutions in support of ever increasing population demands. And it does explain historical changes in the biosphere

River under anthropogenic stress: An isotope study of carbon cycling in the Vistula, Poland

International Nuclear Information System (INIS)

Wachniew, P.; Rozanski, K.

2002-01-01

Rivers play an important role in global carbon cycling as they transform and transport substantial amounts of carbon derived from the terrestrial systems to the oceans. Riverine carbon cycling is affected by anthropogenic influences on hydrology, chemistry and biology of the river and its catchment. The Vistula, one of the most mineralized rivers of the world, drains industrialized and agriculturally-used areas populated by almost 23 million inhabitants. Moreover, much of the industrial and domestic wastewaters discharged into the Vistula river are untreated or insufficiently treated. High levels of pollution have serious environmental and economical consequences. For example, they limit use of Vistula waters as a source of drinking water and for industrial purposes. Pollutants transported by the Vistula river significantly influence water quality far into the open Baltic Sea. The aim of the paper is to show how stable isotope techniques can be used to assess human impact on sources, fluxes and fate of dissolved inorganic carbon (DIC) and other pollutants in rivers, taking the Vistula river as an example. Vistula waters were sampled over a one-year period at Krakow (upper reaches), where the anthropogenic influences are at the extreme, and at the river mouth. Two campaigns were undertaken to sample the Vistula river along its course in summer and in autumn. Analyses of river water included temperature, pH, alkalinity, conductivity, dissolved oxygen, δ 13 C of dissolved inorganic carbon and stable isotope composition of water (δ 18 O and δ 2 H)

Natural and anthropogenic radiation exposure of humans in Germany

International Nuclear Information System (INIS)

Koelzer, Winfried

2016-12-01

The contribution on natural and anthropogenic radiation exposure in Germany covers the following issues: (1) natural radiation exposure: external radiation exposure - cosmic and terrestric radiation, internal radiation exposure - primordial and cosmogenic radionuclides; radiation exposure due to sola neutrinos and geo-neutrinos. (2) Anthropogenic radiation exposure: radiation exposure in medicine, radioactivity in industrial products, radiation exposure during flights, radiation exposure due to nuclear facilities, radiation exposure due to fossil energy carriers in power generation, radiation exposure due to nuclear explosions, radiation exposure due to nuclear accidents. (3) Occupational radiation exposure in Germany: radiation monitoring with personal dosimeters in medicine and industry, dose surveillance of the aviation personal, working places with increases radiation exposure by natural radiation sources.

Anthropogenic Forcing of Carbonate and Organic Carbon Preservation in Marine Sediments.

Science.gov (United States)

Keil, Richard

2017-01-03

Carbon preservation in marine sediments, supplemented by that in large lakes, is the primary mechanism that moves carbon from the active surficial carbon cycle to the slower geologic carbon cycle. Preservation rates are low relative to the rates at which carbon moves between surface pools, which has led to the preservation term largely being ignored when evaluating anthropogenic forcing of the global carbon cycle. However, a variety of anthropogenic drivers-including ocean warming, deoxygenation, and acidification, as well as human-induced changes in sediment delivery to the ocean and mixing and irrigation of continental margin sediments-all work to decrease the already small carbon preservation term. These drivers affect the cycling of both carbonate and organic carbon in the ocean. The overall effect of anthropogenic forcing in the modern ocean is to decrease delivery of carbon to sediments, increase sedimentary dissolution and remineralization, and subsequently decrease overall carbon preservation.

U.S. ozone air quality under changing climate and anthropogenic emissions.

Science.gov (United States)

Racherla, Pavan N; Adams, Peter J

2009-02-01

We examined future ozone (O3) air quality in the United States (U.S.) under changing climate and anthropogenic emissions worldwide by performing global climate-chemistry simulations, utilizing various combinations of present (1990s) and future (Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A2 2050s) climates, and present and future (2050s; IPCC SRES A2 and B1) anthropogenic emissions. The A2 climate scenario is employed here because it lies at the upper extreme of projected climate change for the 21st century. To examine the sensitivity of U.S. O3 to regional emissions increases (decreases), the IPCC SRES A2 and B1 scenarios, which have overall higher and lower O3-precursor emissions for the U.S., respectively, have been chosen. We find that climate change, by itself, significantly worsens the severity and frequency of high-O3 events ("episodes") over most locations in the U.S., with relatively small changes in average O3 air quality. These high-O3 increases due to climate change alone will erode moderately the gains made under a U.S. emissions reduction scenario (e.g., B1). The effect of climate change on high- and average-O3 increases with anthropogenic emissions. Insofar as average O3 air quality is concerned, changes in U.S. anthropogenic emissions will play the most important role in attaining (or not) near-term U.S. O3 air quality standards. However, policy makers must plan appropriately for O3 background increases due to projected increases in global CH4 abundance and non-U.S. anthropogenic emissions, as well as potential local enhancements that they could cause. These findings provide strong incentives for more-than-planned emissions reductions at locations that are currently O3-nonattainment.

The effects of environmental chemical carcinogens on the microRNA machinery.

Science.gov (United States)

Izzotti, A; Pulliero, A

2014-07-01

The first evidence that microRNA expression is early altered by exposure to environmental chemical carcinogens in still healthy organisms was obtained for cigarette smoke. To date, the cumulative experimental data indicate that similar effects are caused by a variety of environmental carcinogens, including polycyclic aromatic hydrocarbons, nitropyrenes, endocrine disruptors, airborne mixtures, carcinogens in food and water, and carcinogenic drugs. Accordingly, the alteration of miRNA expression is a general mechanism that plays an important pathogenic role in linking exposure to environmental toxic agents with their pathological consequences, mainly including cancer development. This review summarizes the existing experimental evidence concerning the effects of chemical carcinogens on the microRNA machinery. For each carcinogen, the specific microRNA alteration signature, as detected in experimental studies, is reported. These data are useful for applying microRNA alterations as early biomarkers of biological effects in healthy organisms exposed to environmental carcinogens. However, microRNA alteration results in carcinogenesis only if accompanied by other molecular damages. As an example, microRNAs altered by chemical carcinogens often inhibits the expression of mutated oncogenes. The long-term exposure to chemical carcinogens causes irreversible suppression of microRNA expression thus allowing the transduction into proteins of mutated oncogenes. This review also analyzes the existing knowledge regarding the mechanisms by which environmental carcinogens alter microRNA expression. The underlying molecular mechanism involves p53-microRNA interconnection, microRNA adduct formation, and alterations of Dicer function. On the whole, reported findings provide evidence that microRNA analysis is a molecular toxicology tool that can elucidate the pathogenic mechanisms activated by environmental carcinogens. Copyright © 2014 Elsevier GmbH. All rights reserved.

Exploring the Impacts of Anthropogenic Disturbance on Seawater and Sediment Microbial Communities in Korean Coastal Waters Using Metagenomics Analysis

Directory of Open Access Journals (Sweden)

Nam-Il Won

2017-01-01

Full Text Available The coastal ecosystems are considered as one of the most dynamic and vulnerable environments under various anthropogenic developments and the effects of climate change. Variations in the composition and diversity of microbial communities may be a good indicator for determining whether the marine ecosystems are affected by complex forcing stressors. DNA sequence-based metagenomics has recently emerged as a promising tool for analyzing the structure and diversity of microbial communities based on environmental DNA (eDNA. However, few studies have so far been performed using this approach to assess the impacts of human activities on the microbial communities in marine systems. In this study, using metagenomic DNA sequencing (16S ribosomal RNA gene, we analyzed and compared seawater and sediment communities between sand mining and control (natural sites in southern coastal waters of Korea to assess whether anthropogenic activities have significantly affected the microbial communities. The sand mining sites harbored considerably lower levels of microbial diversities in the surface seawater community during spring compared with control sites. Moreover, the sand mining areas had distinct microbial taxonomic group compositions, particularly during spring season. The microbial groups detected solely in the sediment load/dredging areas (e.g., Marinobacter, Alcanivorax, Novosphingobium are known to be involved in degradation of toxic chemicals such as hydrocarbon, oil, and aromatic compounds, and they also contain potential pathogens. This study highlights the versatility of metagenomics in monitoring and diagnosing the impacts of human disturbance on the environmental health of marine ecosystems from eDNA.

Effects of urbanization on animal behaviour : patterns, underlying mechanisms and ultimate causes

OpenAIRE

Miranda, Ana Catarina Sequeira Nunes Coutinho de

2014-01-01

Human-altered environmental conditions affect many species at the global scale. An extreme form of anthropogenic alteration is the existence and rapid increase of urban areas. A key question is how animals cope with urbanization. In order to live in cities, animals have to adjust their behaviour and life histories to the urban novel environment.The main objectives of this thesis were to investigate (i) the existence of behavioural changes related to the urbanization process, (ii) the ultimate...

443 ANTHROPOGENIC IMPACTS ON CORAL REEFS AND THEIR ...

African Journals Online (AJOL)

Osondu

Data collection methodology included household questionnaire survey, key informant interviews, participant .... Anthropogenic Impacts on Coral Reefs and Their Effect on Fishery ................Mbije & ... common along Kilwa coastline, away of large markets ... questionnaire whereas content analysis was used for analyzing ...

Environmental clustering of lakes to evaluate performance of a macrophyte index of biotic integrity

Science.gov (United States)

Vondracek, Bruce C.; Vondracek, Bruce; Hatch, Lorin K.

2013-01-01

Proper classification of sites is critical for the use of biological indices that can distinguish between natural and human-induced variation in biological response. The macrophyte-based index of biotic integrity was developed to assess the condition of Minnesota lakes in relation to anthropogenic stressors, but macrophyte community composition varies naturally across the state. The goal of the study was to identify environmental characteristics that naturally influence macrophyte index response and establish a preliminary lake classification scheme for biological assessment (bioassessment). Using a comprehensive set of environmental variables, we identified similar groups of lakes by clustering using flexible beta classification. Variance partitioning analysis of IBI response indicated that evaluating similar lake clusters could improve the ability of the macrophyte index to identify community change to anthropogenic stressors, although lake groups did not fully account for the natural variation in macrophyte composition. Diagnostic capabilities of the index could be improved when evaluating lakes with similar environmental characteristics, suggesting the index has potential for accurate bioassessment provided comparable groups of lakes are evaluated.

Anthropogenic host plant expansion leads a nettle-feeding butterfly out of the forest: consequences for larval survival and developmental plasticity in adult morphology

OpenAIRE

Merckx, Thomas; Serruys, Mélanie; Van Dyck, Hans

2015-01-01

Recent anthropogenic eutrophication has meant that host plants of nettle-feeding insects became quasi-omnipresent in fertile regions of Western Europe. However, host plant resource quality – in terms of microclimate and nutritional value – may vary considerably between the ‘original’ forest habitat and ‘recent’ agricul- tural habitat. Here, we compared development in both environmental settings using a split-brood design, so as to explore to what extent larval survival and adult morphology in...

Anthropogenic resource subsidies determine space use by Australian arid zone dingoes: an improved resource selection modelling approach.

Directory of Open Access Journals (Sweden)

Thomas M Newsome

Full Text Available Dingoes (Canis lupus dingo were introduced to Australia and became feral at least 4,000 years ago. We hypothesized that dingoes, being of domestic origin, would be adaptable to anthropogenic resource subsidies and that their space use would be affected by the dispersion of those resources. We tested this by analyzing Resource Selection Functions (RSFs developed from GPS fixes (locations of dingoes in arid central Australia. Using Generalized Linear Mixed-effect Models (GLMMs, we investigated resource relationships for dingoes that had access to abundant food near mine facilities, and for those that did not. From these models, we predicted the probability of dingo occurrence in relation to anthropogenic resource subsidies and other habitat characteristics over ∼ 18,000 km(2. Very small standard errors and subsequent pervasively high P-values of results will become more important as the size of data sets, such as our GPS tracking logs, increases. Therefore, we also investigated methods to minimize the effects of serial and spatio-temporal correlation among samples and unbalanced study designs. Using GLMMs, we accounted for some of the correlation structure of GPS animal tracking data; however, parameter standard errors remained very small and all predictors were highly significant. Consequently, we developed an alternative approach that allowed us to review effect sizes at different spatial scales and determine which predictors were sufficiently ecologically meaningful to include in final RSF models. We determined that the most important predictor for dingo occurrence around mine sites was distance to the refuse facility. Away from mine sites, close proximity to human-provided watering points was predictive of dingo dispersion as were other landscape factors including palaeochannels, rocky rises and elevated drainage depressions. Our models demonstrate that anthropogenically supplemented food and water can alter dingo-resource relationships. The

The effects of demographic, social, and environmental characteristics on pathogen prevalence in wild felids across a gradient of urbanization.

Directory of Open Access Journals (Sweden)

Jesse S Lewis

Full Text Available Transmission of pathogens among animals is influenced by demographic, social, and environmental factors. Anthropogenic alteration of landscapes can impact patterns of disease dynamics in wildlife populations, increasing the potential for spillover and spread of emerging infectious diseases in wildlife, human, and domestic animal populations. We evaluated the effects of multiple ecological mechanisms on patterns of pathogen exposure in animal populations. Specifically, we evaluated how ecological factors affected the prevalence of Toxoplasma gondii (Toxoplasma, Bartonella spp. (Bartonella, feline immunodeficiency virus (FIV, and feline calicivirus (FCV in bobcat and puma populations across wildland-urban interface (WUI, low-density exurban development, and wildland habitat on the Western Slope (WS and Front Range (FR of Colorado during 2009-2011. Samples were collected from 37 bobcats and 29 pumas on the WS and FR. As predicted, age appeared to be positively related to the exposure to pathogens that are both environmentally transmitted (Toxoplasma and directly transmitted between animals (FIV. In addition, WS bobcats appeared more likely to be exposed to Toxoplasma with increasing intraspecific space-use overlap. However, counter to our predictions, exposure to directly-transmitted pathogens (FCV and FIV was more likely with decreasing space-use overlap (FCV: WS bobcats and potential intraspecific contacts (FIV: FR pumas. Environmental factors, including urbanization and landscape covariates, were generally unsupported in our models. This study is an approximation of how pathogens can be evaluated in relation to demographic, social, and environmental factors to understand pathogen exposure in wild animal populations.

Evaluating anthropogenic risk of grassland and forest habitat degradation using land-cover data

Science.gov (United States)

Kurt Riitters; James Wickham; Timothy Wade

2009-01-01

The effects of landscape context on habitat quality are receiving increased attention in conservation biology. The objective of this research is to demonstrate a landscape-level approach to mapping and evaluating the anthropogenic risks of grassland and forest habitat degradation by examining habitat context as defined by intensive anthropogenic land uses at multiple...

Hydropower Production and Fish Habitat Suitability: Impact and Effectiveness of Environmental Flow Prescriptions

Science.gov (United States)

Castellarin, A.; Galeati, G.; Ceola, S.; Pugliese, A.; Ventura, M.; Montanari, A.

2017-12-01

The anthropogenic alteration of the natural flow regime of a river for hydropower production can significantly modify the processes and functions associated with fluvial ecosystems. In order to preserve the fluvial habitat downstream of dams and diversion structures, environmental flows are commonly defined. Such environmental flows are generally computed from empirical methodologies, which are seldom based on site-specific studies, and may not be representative of local ecological and hydraulic conditions. Here we present the results of a quantitative analysis on the effectiveness of two alternative environmental flow scenarios prescribed in Central Italy (time-invariant experimental and empirically-based flow release versus time-variant hydrogeomorphologically-based flow release) and their impact on hydropower production and fish habitat suitability. The latter is examined by means of several models of habitat suitability curve, which is a well-known approach capable of analysing fluvial species preferences as a function of key eco-hydraulic features, such as water depth, flow velocity and river substrate. The results show an evident loss of hydropower production moving from the time-invariant experimental flow release to the hydrogeomorphological one (nearly 20% at the annual scale). Concerning the effects in terms of fish habitat suitability, our outcomes are less obvious, since they are species- and life stage-specific. The proposed analysis, which can be easily adapted to different riparian habitats and hydrological contexts, is a useful tool to guide the derivation of optimal water resource management strategies in order to ensure both hydropower production and fluvial ecosystem protection.

Changes in anthropogenic carbon storage in the Northeast Pacific in the last decade

Science.gov (United States)

Chu, Sophie N.; Wang, Zhaohui Aleck; Doney, Scott C.; Lawson, Gareth L.; Hoering, Katherine A.

2016-07-01

In order to understand the ocean's role as a sink for anthropogenic carbon dioxide (CO2), it is important to quantify changes in the amount of anthropogenic CO2 stored in the ocean interior over time. From August to September 2012, an ocean acidification cruise was conducted along a portion of the P17N transect (50°N 150°W to 33.5°N 135°W) in the Northeast Pacific. These measurements are compared with data from the previous occupation of this transect in 2001 to estimate the change in the anthropogenic CO2 inventory in the Northeast Pacific using an extended multiple linear regression (eMLR) approach. Maximum increases in the surface waters were 11 µmol kg-1 over 11 years near 50°N. Here, the penetration depth of anthropogenic CO2 only reached ˜300 m depth, whereas at 33.5°N, penetration depth reached ˜600 m. The average increase of the depth-integrated anthropogenic carbon inventory was 0.41 ± 0.12 mol m-2 yr-1 across the transect. Lower values down to 0.20 mol m-2 yr-1 were observed in the northern part of the transect near 50°N and increased up to 0.55 mol m-2 yr-1 toward 33.5°N. This increase in anthropogenic carbon in the upper ocean resulted in an average pH decrease of 0.002 ± 0.0003 pH units yr-1 and a 1.8 ± 0.4 m yr-1 shoaling rate of the aragonite saturation horizon. An average increase in apparent oxygen utilization of 13.4 ± 15.5 µmol kg-1 centered on isopycnal surface 26.6 kg m-3 from 2001 to 2012 was also observed.

Challenges for present and future estimates of anthropogenic carbon in the Indian Ocean

Science.gov (United States)

Goyet, C.; Touratier, F.

One of the main challenges we face today is to determine the evolution of the penetration of anthropogenic CO2 into the Indian Ocean and its impacts on marine and human life. Anthropogenic CO2 reaches the ocean via air-sea interactions as well as riverine inputs. It is then stored in the ocean and follows the oceanic circulation. As the carbon dioxide from the atmosphere penetrates into the sea, it reacts with water and acidifies the ocean. Consequently, the whole marine ecosystem is perturbed, thus potentially affecting the food web, which has, in turn, a direct impact on seafood supply for humans. Naturally, this will mainly affect the growing number of people living in coastal areas. Although anthropogenic CO2 in the ocean is identical with natural CO2 and therefore cannot be detected alone, many approaches are available today to estimate it. Since most of the results of these methods are globally in agreement, here we chose one of these methods, the tracer using oxygen, total inorganic carbon, and total alkalinity (TrOCA) approach, to compute the 3-D distribution of the anthropogenic CO2 concentrations throughout the Indian Ocean. The results of this distribution clearly illustrate the contrast between the Arabian Sea and the Bay of Bengal. They further show the importance of the southern part of this ocean that carries some anthropogenic CO2 at great depths. In order to determine the future anthropogenic impacts on the Indian Ocean, it is urgent and necessary to understand the present state. As the seawater temperature increases, how and how fast will the ocean circulation change? What will the impacts on seawater properties be? Many people are living on the bordering coasts, how will they be affected?

Glacial recharge, salinisation and anthropogenic contamination in the coastal aquifers of Recife (Brazil)

Energy Technology Data Exchange (ETDEWEB)

Chatton, E., E-mail: eliot.chatton@gmail.com [Géosciences Rennes, Université Rennes 1-CNRS, UMR 6118, adress: 263 av du général Leclerc, Campus de Beaulieu, bat 15, 35042 Rennes Cedex (France); Aquilina, L., E-mail: luc.aquilina@univ-rennes1.fr [Géosciences Rennes, Université Rennes 1-CNRS, UMR 6118, adress: 263 av du général Leclerc, Campus de Beaulieu, bat 15, 35042 Rennes Cedex (France); Pételet-Giraud, E., E-mail: e.petelet@brgm.fr [Bureau de Recherches Géologiques et Minières (BRGM), adress: 3 avenue Claude-Guillemin, BP 36009, 45060 Orléans Cedex 2 (France); Cary, L., E-mail: l.cary@brgm.fr [Bureau de Recherches Géologiques et Minières (BRGM), adress: 3 avenue Claude-Guillemin, BP 36009, 45060 Orléans Cedex 2 (France); Bertrand, G., E-mail: guillaume353@gmail.com [Instituto de Geociências, CEPAS (Groundwater Research Center), University of São Paulo, adress: Rua do lago 562, 05508-080 Sao Paulo (Brazil); Labasque, T., E-mail: thierry.labasque@univ-rennes1.fr [Géosciences Rennes, Université Rennes 1-CNRS, UMR 6118, adress: 263 av du général Leclerc, Campus de Beaulieu, bat 15, 35042 Rennes Cedex (France); and others

2016-11-01

Implying large residence times and complex water origins deep coastal aquifers are of particular interest as they are remarkable markers of climate, water use and land use changes. Over the last decades, the Metropolitan Region of Recife (Brazil) went through extensive environmental changes increasing the pressure on water resources and giving rise to numerous environmental consequences on the coastal groundwater systems. We analysed the groundwater of the deep aquifers Cabo and Beberibe that are increasingly exploited. The processes potentially affecting groundwater residence times and flow paths have been studied using a multi-tracer approach (CFCs, SF6, noble gases, 14C, 2H and 18O). The main findings of these investigations show that: (1) Groundwaters of the Cabo and Beberibe aquifers have long residence times and were recharged about 20,000 years ago. (2) Within these old groundwaters we can find palaeo-climate evidences from the last glacial period at the tropics with lower temperatures and dryer conditions than the present climate. (3) Recently, the natural slow dynamic of these groundwater systems was significantly affected by mixing processes with contaminated modern groundwater coming from the shallow unconfined Boa Viagem aquifer. (4) The large exploitation of these aquifers leads to a modification of the flow directions and causes the intrusion through palaeo-channels of saline water probably coming from the Capibaribe River and from the last transgression episodes. These observations indicate that the current exploitation of the Cabo and Beberibe aquifers is unsustainable regarding the long renewal times of these groundwater systems as well as their ongoing contamination and salinisation. The groundwater cycle being much slower than the human development rhythm, it is essential to integrate the magnitude and rapidity of anthropogenic impacts on this extremely slow cycle to the water management concepts. - Highlights: • Study of anthropogenic impacts

Glacial recharge, salinisation and anthropogenic contamination in the coastal aquifers of Recife (Brazil)

International Nuclear Information System (INIS)

Chatton, E.; Aquilina, L.; Pételet-Giraud, E.; Cary, L.; Bertrand, G.; Labasque, T.

2016-01-01

Implying large residence times and complex water origins deep coastal aquifers are of particular interest as they are remarkable markers of climate, water use and land use changes. Over the last decades, the Metropolitan Region of Recife (Brazil) went through extensive environmental changes increasing the pressure on water resources and giving rise to numerous environmental consequences on the coastal groundwater systems. We analysed the groundwater of the deep aquifers Cabo and Beberibe that are increasingly exploited. The processes potentially affecting groundwater residence times and flow paths have been studied using a multi-tracer approach (CFCs, SF6, noble gases, 14C, 2H and 18O). The main findings of these investigations show that: (1) Groundwaters of the Cabo and Beberibe aquifers have long residence times and were recharged about 20,000 years ago. (2) Within these old groundwaters we can find palaeo-climate evidences from the last glacial period at the tropics with lower temperatures and dryer conditions than the present climate. (3) Recently, the natural slow dynamic of these groundwater systems was significantly affected by mixing processes with contaminated modern groundwater coming from the shallow unconfined Boa Viagem aquifer. (4) The large exploitation of these aquifers leads to a modification of the flow directions and causes the intrusion through palaeo-channels of saline water probably coming from the Capibaribe River and from the last transgression episodes. These observations indicate that the current exploitation of the Cabo and Beberibe aquifers is unsustainable regarding the long renewal times of these groundwater systems as well as their ongoing contamination and salinisation. The groundwater cycle being much slower than the human development rhythm, it is essential to integrate the magnitude and rapidity of anthropogenic impacts on this extremely slow cycle to the water management concepts. - Highlights: • Study of anthropogenic impacts

Impact of anthropogenic activities on the dissemination of antibiotic resistance across ecological boundaries.

Science.gov (United States)

Tripathi, Vijay; Cytryn, Eddie

2017-02-28

Antibiotics are considered to be one of the major medical breakthroughs in history. Nonetheless, over the past four decades, antibiotic resistance has reached alarming levels worldwide and this trend is expected to continue to increase, leading some experts to forecast the coming of a 'post-antibiotic' era. Although antibiotic resistance in pathogens is traditionally linked to clinical environments, there is a rising concern that the global propagation of antibiotic resistance is also associated with environmental reservoirs that are linked to anthropogenic activities such as animal husbandry, agronomic practices and wastewater treatment. It is hypothesized that the emergence and dissemination of antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) within and between environmental microbial communities can ultimately contribute to the acquisition of antibiotic resistance in human pathogens. Nonetheless, the scope of this phenomenon is not clear due to the complexity of microbial communities in the environment and methodological constraints that limit comprehensive in situ evaluation of microbial genomes. This review summarizes the current state of knowledge regarding antibiotic resistance in non-clinical environments, specifically focusing on the dissemination of antibiotic resistance across ecological boundaries and the contribution of this phenomenon to global antibiotic resistance. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Assessing the observed impact of anthropogenic climate change

NARCIS (Netherlands)

Hansen, G.E.

2015-01-01

Assessing the observed impact of anthropogenic climate change

Gerrit Hansen

Global climate change is unequivocal, and greenhouse gas emissions continue rising despite international mitigation efforts. Hence whether and to what extent the impacts of human induced

Disentangling the environmental heterogeneity, floristic distinctiveness and current threats of tropical dry forests in Colombia

Science.gov (United States)

González-M, Roy; García, Hernando; Isaacs, Paola; Cuadros, Hermes; López-Camacho, René; Rodríguez, Nelly; Pérez, Karen; Mijares, Francisco; Castaño-Naranjo, Alejandro; Jurado, Rubén; Idárraga-Piedrahíta, Álvaro; Rojas, Alicia; Vergara, Hernando; Pizano, Camila

2018-04-01

Tropical dry forests (TDFs) have been defined as a single biome occurring mostly in the lowlands where there is a marked period of drought during the year. In the Neotropics, dry forests occur across contrasting biogeographical regions that contain high beta diversity and endemism, but also strong anthropogenic pressures that threaten their biodiversity and ecological integrity. In Colombia, TDFs occur across six regions with contrasting soils, climate, and anthropogenic pressures, therefore being ideal for studying how these variables relate to dry forest species composition, successional stage and conservation status. Here, we explore the variation in climate and soil conditions, floristic composition, forest fragment size and shape, successional stage and anthropogenic pressures in 571 dry forest fragments across Colombia. We found that TDFs should not be classified solely on rainfall seasonality, as high variation in precipitation and temperature were correlated with soil characteristics. In fact, based on environmental factors and floristic composition, the dry forests of Colombia are clustered in three distinctive groups, with high species turnover across and within regions, as reported for other TDF regions of the Neotropics. Widely distributed TDF species were found to be generalists favored by forest disturbance and the early successional stages of dry forests. On the other hand, TDF fragments were not only small in size, but highly irregular in shape in all regions, and comprising mostly early and intermediate successional stages, with very little mature forest left at the national level. At all sites, we detected at least seven anthropogenic disturbances with agriculture, cattle ranching and human infrastructure being the most pressing disturbances throughout the country. Thus, although environmental factors and floristic composition of dry forests vary across regions at the national level, dry forests are equally threatened by deforestation, degradation

Effects of wetland vs. landscape variables on parasite communities of Rana pipiens: links to anthropogenic factors

Science.gov (United States)

Schotthoefer, Anna M.; Rohr, Jason R.; Cole, Rebecca A.; Koehler, Anson V.; Johnson, Catherine M.; Johnson, Lucinda B.; Beasley, Val R.

2011-01-01

The emergence of several diseases affecting amphibian populations worldwide has prompted investigations into determinants of the occurrence and abundance of parasites in frogs. To understand the spatial scales and identify specific environmental factors that determine risks of parasitism in frogs, helminth communities in metamorphic frogs of the northern leopard frog (Rana pipiens) were examined in relation to wetland and landscape factors at local (1 km) and regional (10 km) spatial extents in an agricultural region of Minnesota (USA) using regression analyses, ordination, and variance partitioning techniques. Greater amounts of forested and woody wetland habitats, shorter distances between woody wetlands, and smaller-sized open water patches in surrounding landscapes were the most consistently positive correlates with the abundances, richness, and diversity of helminths found in the frogs. Wetland and local landscape variables were suggested as most important for larval trematode abundances, whereas local and regional landscape variables appeared most important for adult helminths. As previously reported, the sum concentration of atrazine and its metabolite desethylatrazine, was the strongest predictor of larval trematode communities. In this report, we highlight the additional influences of landscape factors. In particular, our data suggest that anthropogenic activities that have resulted in the loss of the availability and connectivity of suitable habitats in the surrounding landscapes of wetlands are associated with declines in helminth richness and abundance, but that alteration of wetland water quality through eutrophication or pesticide contamination may facilitate the transmission of certain parasite taxa when they are present at wetlands. Although additional research is needed to quantify the negative effects of parasitism on frog populations, efforts to reduce inputs of agrochemicals into wetlands to limit larval trematode infections may be warranted

Characterization of anthropogenic sediment particles after a transboundary water pollution of river Tisza using synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Osan, Janos E-mail: osan@sunserv.kfki.hu; Toeroek, Szabina; Alfoeldy, Balint; Falkenberg, Gerald

2004-05-21

At the beginning of 2000, a major mining accident occurred in the Romanian part of the Tisza catchment area due to tailings dam failure releasing huge amounts of heavy metals to the river. Sediment samples were taken from the main riverbed at six sites in Hungary, on March 16, 2000. The objective of this work was to characterize the anthropogenic particles in river sediment previously selected by single-particle electron probe X-ray microanalysis (EPMA). The trace element composition, heterogeneity and heavy metal speciation of individual particles was studied using synchrotron radiation-based microbeam X-ray emission and absorption methods. Particles were selected only from samples regarded as polluted sediment. White-beam micro X-ray fluorescence ({mu}-XRF) allowed the quantitative determination of heavy metals such as cadmium in individual particles. The maximum observed concentration of cadmium (>700 {mu}g/g) indicates that this highly toxic heavy metal is concentrated in individual anthropogenic particles. Using the combination of micro X-ray absorption near-edge structure and target-transformation principle component analysis, quantitative chemical speciation of copper and zinc was feasible on individual sediment particles. Heavy metals in most of the particles released from the pollution site remained in the sulfide form resulting in a limited mobility of these metals. Based on the information obtained using microanalytical methods, the estimation of the environmental mobility of heavy metals connected to microparticles becomes possible.

Quantifying Anthropogenic Stress on Groundwater Resources

OpenAIRE

Ashraf, Batool; AghaKouchak, Amir; Alizadeh, Amin; Mousavi Baygi, Mohammad; R. Moftakhari, Hamed; Mirchi, Ali; Anjileli, Hassan; Madani, Kaveh

2017-01-01

This study explores a general framework for quantifying anthropogenic influences on groundwater budget based on normalized human outflow (hout) and inflow (hin). The framework is useful for sustainability assessment of groundwater systems and allows investigating the effects of different human water abstraction scenarios on the overall aquifer regime (e.g., depleted, natural flow-dominated, and human flow-dominated). We apply this approach to selected regions in the USA, Germany and Iran to e...

Simple but accurate GCM-free approach for quantifying anthropogenic climate change

Science.gov (United States)

Lovejoy, S.

2014-12-01

We are so used to analysing the climate with the help of giant computer models (GCM's) that it is easy to get the impression that they are indispensable. Yet anthropogenic warming is so large (roughly 0.9oC) that it turns out that it is straightforward to quantify it with more empirically based methodologies that can be readily understood by the layperson. The key is to use the CO2 forcing as a linear surrogate for all the anthropogenic effects from 1880 to the present (implicitly including all effects due to Greenhouse Gases, aerosols and land use changes). To a good approximation, double the economic activity, double the effects. The relationship between the forcing and global mean temperature is extremely linear as can be seen graphically and understood without fancy statistics, [Lovejoy, 2014a] (see the attached figure and http://www.physics.mcgill.ca/~gang/Lovejoy.htm). To an excellent approximation, the deviations from the linear forcing - temperature relation can be interpreted as the natural variability. For example, this direct - yet accurate approach makes it graphically obvious that the "pause" or "hiatus" in the warming since 1998 is simply a natural cooling event that has roughly offset the anthropogenic warming [Lovejoy, 2014b]. Rather than trying to prove that the warming is anthropogenic, with a little extra work (and some nonlinear geophysics theory and pre-industrial multiproxies) we can disprove the competing theory that it is natural. This approach leads to the estimate that the probability of the industrial scale warming being a giant natural fluctuation is ≈0.1%: it can be dismissed. This destroys the last climate skeptic argument - that the models are wrong and the warming is natural. It finally allows for a closure of the debate. In this talk we argue that this new, direct, simple, intuitive approach provides an indispensable tool for communicating - and convincing - the public of both the reality and the amplitude of anthropogenic warming

Climate effects of anthropogenic sulfate: Simulations from a coupled chemistry/climate model

International Nuclear Information System (INIS)

Chuang, C.C.; Penner, J.E.; Taylor, K.E.; Walton, J.J.

1993-09-01

In this paper, we use a more comprehensive approach by coupling a climate model with a 3-D global chemistry model to investigate the forcing by anthropogenic aerosol sulfate. The chemistry model treats the global-scale transport, transformation, and removal of SO 2 , DMS and H 2 SO 4 species in the atmosphere. The mass concentration of anthropogenic sulfate from fossil fuel combustion and biomass burning is calculated in the chemistry model and provided to the climate model where it affects the shortwave radiation. We also investigate the effect, with cloud nucleation parameterized in terms of local aerosol number, sulfate mass concentration and updraft velocity. Our simulations indicate that anthropogenic sulfate may result in important increases in reflected solar radiation, which would mask locally the radiative forcing from increased greenhouse gases. Uncertainties in these results will be discussed

Caspian Sea water balance and dynamics studies using anthropogenic radionuclides: Implications for environmental changes

International Nuclear Information System (INIS)

Oregioni, B.; Gastaud, J.; Pham, M.K.; Povinec, P.P.

2002-01-01

Full text: Environmental changes in the Caspian Sea have recently become of great interest in connection with fluctuations in sea level changes. Radioactive and stable isotopes have been used as powerful tracers to investigate water balance and dynamics and have contributed significantly to understanding climatically driven environmental changes in the Caspian Sea. The Caspian Sea is the world largest inland water body with a surface area of about 386000 km 2 and a volume of about 67000 km 3 , located in a large continental depression about 28 m below sea level. With no surface outlet, the Caspian Sea is particularly sensitive to climatic variations. The drainage area of the Caspian Sea is approximately 3.7 million square kilometers. The Volga, Ural and Terek empty into the North Caspian, with their combined annual flow accounting for 88% of all water entering the sea. The Sulak, Samur, Kura and a number of small rivers contribute about 7% of the inflow, the remainder comes from the rivers of the Iranian shore. The Caspian Sea is divided into three basins with approximately the same surface. The North Caspian Basin, maximum depth 15 m, average depth 5 m, contains 1% of the total water. The Middle Caspian (or Central) Basin has a maximum depth of 800 m and contains 22% of the total water. The South Caspian Basin, maximum depth 1024 m, average depth 330 m, contains 77% of the total Caspian Sea water. Recently there have been concerns over the environmental conditions of the Caspian Sea, especially over observed sea level changes, which have had a strong impact on the region. Anthropogenic radionuclides like 90 Sr, 137 Cs and 239 , 240 Pu are particularly useful tracers for the investigation of water dynamics. Two research-training cruises were carried out in September 1995 and August-September 1996. At every station, 60-70 liters samples of seawater from different depths were processed for sequential separation of plutonium, cesium and strontium isotopes. This was

Combined effects of local habitat, anthropogenic stress, and dispersal on stream ecosystems: a mesocosm experiment.

Science.gov (United States)

Turunen, Jarno; Louhi, Pauliina; Mykrä, Heikki; Aroviita, Jukka; Putkonen, Emmi; Huusko, Ari; Muotka, Timo

2018-06-06

The effects of anthropogenic stressors on community structure and ecosystem functioning can be strongly influenced by local habitat structure and dispersal from source communities. Catchment land uses increase the input of fine sediments into stream channels, clogging the interstitial spaces of benthic habitats. Aquatic macrophytes enhance habitat heterogeneity and mediate important ecosystem functions, being thus a key component of habitat structure in many streams. Therefore, the recovery of macrophytes following in-stream habitat modification may be prerequisite for successful stream restoration. Restoration success is also affected by dispersal of organisms from the source community, with potentially strongest responses in relatively isolated headwater sites that receive limited amount of dispersing individuals. We used a factorial design in a set of stream mesocosms to study the independent and combined effects of an anthropogenic stressor (sand sedimentation), local habitat (macrophytes, i.e. moss transplants) and enhanced dispersal (two levels: high vs. low) on organic matter retention, algal accrual rate, leaf decomposition and macroinvertebrate community structure. Overall, all responses were simple additive effects with no interactions between treatments. Sand reduced algal accumulation, total invertebrate density and density of a few individual taxa. Mosses reduced algal accrual rate and algae-grazing invertebrates, but enhanced organic matter retention and detritus- and filter-feeders. Mosses also reduced macroinvertebrate diversity by increasing the dominance by a few taxa. Mosses also reduced leaf-mass loss, possibly because the organic matter retained by mosses provided an additional food source for leaf-shredding invertebrates and thus reduced shredder aggregation into leaf packs. The effect of mosses on macroinvertebrate communities and ecosystem functioning was distinct irrespective of the level of dispersal, suggesting strong environmental

IDENTIFYING ANTHROPOGENIC METALLIC POLLUTANTS USING FREQUENCY DEPENDENT MAGNETIC SUSCEPTIBILITY MEASUREMENTS IN ABUJA METROPOLIS

Directory of Open Access Journals (Sweden)

Jatto S. Solomon

2017-07-01

Full Text Available Soil formed from lithological and weathering processes of parent rocks generally exhibit paramagnetic properties due to some minerals contained in the rocks and thus have significant value of magnetic susceptibility. This susceptibility arising from the influence of the parent rocks tend to mask anthropogenic grains pollutants released into the environment by human activities. Hence, it becomes difficult to identify the effect of the lithological and anthropogenic magnetic susceptibility in complex soil found in urban areas. The superparamagnetic effect of lithological soil, a single state domain and multi-domain state of anthropogenic grains can easily be investigated by frequency dependent measurements where readings between 0-2.0% indicates the absence of lithological influence, 2.0-8.0% indicates multi-domain grains or mixture of both single stage and multi-domian grains and 8.0-12% indicates the superparamagntic (SP grain from lithological origin. In this work frequency dependent measurements were carried out along 5 selected road networks within the 5 districts of Abuja phase 1. Measurements were also carried out in 379 random points at the surface and depth of 40.0cm to investigate the distribution of anthropogenic grains in Abuja metropolis using the Bartington susceptibility meter. Frequency dependent measurements along the selected road networks indicate0-3.0% immediately after the roads pavement to a distance of about 3.0m from the road, indicating that the magnetic susceptibility arise mostly form anthropogenic influence rather than lithological processes. At the distance of 3.0-8.0m, frequency dependent values of about 3.0-8.0% were recorded, indicating mixture of both superparamagnetic and multi-domain grains. Beyond the distance of 8.0m, the frequency dependent values are mostly above 8.0.0%, indicating virtually all SP grains. The spatial distribution frequency dependent surface map shows the presence of anthropogenic grains in

Anthropogenic contributions to mercury levels in present-day Arctic animals-A review

Energy Technology Data Exchange (ETDEWEB)

Dietz, Rune, E-mail: rdi@dmu.dk [National Environmental Research Institute, Department of Arctic Environment, Aarhus University, Roskilde (Denmark); Outridge, Peter M. [Geological Survey of Canada, Ottawa (Canada); Hobson, Keith A. [Environment Canada, Saskatoon (Canada)

2009-12-01

Background: Because of concern about the recently increasing levels of biological Hg in some areas of the Arctic, we examined the literature concerning the long-term changes of Hg in humans and selected Arctic marine mammals and birds of prey since pre-industrial times (i.e. before 1800 A.D.), to determine the anthropogenic contribution to present-day Hg concentrations and the historical timing of any changes. Methods: Mercury data from published articles were extracted on historical and pre-industrial concentrations as percentages of the recent maximum, as well as the man-made contribution was calculated and depicted in a uniform manner to provide an overview of the development over time. Results and discussion: Trends of [Hg] in hard tissues such as teeth, hair and feathers consistently showed that there had been an order-of-magnitude increase of [Hg] in Arctic marine foodweb-based animals that began in the mid- to late-19th Century and accelerated in the 20th Century. The median man-made contribution to present-day Hg concentrations was 92.4% ranging from 74.2 to 94.4%. Confidence in our data was increased by accompanying data in some studies on stable isotopes ({delta}{sup 13}C, {delta}{sup 15}N), which allowed us to normalize where necessary for changes in animal trophic position and feeding location over time, and by careful attention to the possibility of sample chemical diagenesis (Hg contamination or loss) which can alter the Hg content of ancient hard tissues. Conclusions: Wildlife hard tissue matrices provide consistent information with respect to the steep onset of Hg exposure of Arctic wildlife beginning in the latter half of the 19th Century. Today the man-made contribution was found to be above 92%. Stable isotope analyses provide important information to normalize for possible changes in diet over time, and are highly relevant to include when interpreting temporal trends, baseline concentrations as well as man-made anthropogenic contribution of Hg.

Anthropogenic signatures of lead in the Northeast Atlantic

NARCIS (Netherlands)

Rusiecka, D.; Gledhill, M.; Milne, A.; Achterberg, E.P.; Annett, A.L.; Atkinson, S.; Birchill, A.; Karstensen, J.; Lohan, M.; Mariez, C.; Middag, R.; Rolison, J.M.; Tanhua, T.; Ussher, S.; Connelly, D.

2018-01-01

Anthropogenic activities have resulted in enhanced lead (Pb) emissions to the environment over the past century, mainly through the combustion of leaded gasoline. Here we present the first combined dissolved (DPb), labile (LpPb), and particulate (PPb) Pb data set from the Northeast Atlantic (Celtic

Asian river fishes in the Anthropocene: threats and conservation challenges in an era of rapid environmental change.

Science.gov (United States)

Dudgeon, D

2011-12-01

This review compares and contrasts the environmental changes that have influenced, or will influence, fishes and fisheries in the Yangtze and Mekong Rivers. These two rivers have been chosen because they differ markedly in the type and intensity of prevailing threats. The Mekong is relatively pristine, whereas the Three Gorges Dam on the Yangtze is the world's largest dam representing the apotheosis of environmental alteration of Asian rivers thus far. Moreover, it is situated at the foot of a planned cascade of at least 12 new dams on the upper Yangtze. Anthropogenic effects of dams and pollution of Yangtze fishes will be exacerbated by plans to divert water northwards along three transfer routes, in part to supplement the flow of the Yellow River. Adaptation to climate change will undoubtedly stimulate more dam construction and flow regulation, potentially causing perfect storm conditions for fishes in the Yangtze. China has already built dams along the upper course of the Mekong, and there are plans for as many as 11 mainstream dams in People's Democratic Republic (Laos) and Cambodia in the lower Mekong Basin. If built, they could have profound consequences for biodiversity, fisheries and human livelihoods, and such concerns have stalled dam construction. Potential effects of dams proposed for other rivers (such as Nujiang-Salween) are also cause for concern. Conservation or restoration measures to sustain some semblance of the rich fish biodiversity of Asian rivers can be identified, but their implementation may prove problematic in a context of increasing Anthropocene alteration of these ecosystems. © 2011 The Author. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

Environmental science and vulnerable ecosystems. Programme and abstract book

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-11-01

The Society of Environmental Toxicology and Chemistry (SETAC) is a non-profit, professional society established to provide a multi-disciplinary forum for individuals and institutions engaged in the study of environmental problems. SETAC provides a vehicle for scientists to exchange information and share opinions across borders and across disciplines. It does so by organizing international and national meetings, workshops and symposia, by publishing a scientific journal, newsletter and books. There were 228 papers and 291 posters presented by more than 1000 contributors on aqueous and terrestrial ecosystems and their vulnerability to anthropogenic pollution and contamination. (EG)

Environmental science and vulnerable ecosystems. Programme and abstract book

International Nuclear Information System (INIS)

1995-01-01

The Society of Environmental Toxicology and Chemistry (SETAC) is a non-profit, professional society established to provide a multi-disciplinary forum for individuals and institutions engaged in the study of environmental problems. SETAC provides a vehicle for scientists to exchange information and share opinions across border and across disciplines. It does so by organizing international and national meetings, workshops and symposia, by publishing a scientific journal, newsletter and books. There were 228 papers and 291 posters presented by more than 1000 contributors on aqueous and terrestrial ecosystems and their vulnerability to anthropogenic pollution and contamination. (EG)

Attribution of Anthropogenic Influence on Atmospheric Patterns Conducive to Recent Most Severe Haze Over Eastern China

Science.gov (United States)

Li, Ke; Liao, Hong; Cai, Wenju; Yang, Yang

2018-02-01

Severe haze pollution in eastern China has caused substantial health impacts and economic loss. Conducive atmospheric conditions are important to affect occurrence of severe haze events, and circulation changes induced by future global climate warming are projected to increase the frequency of such events. However, a potential contribution of an anthropogenic influence to recent most severe haze (December 2015 and January 2013) over eastern China remains unclear. Here we show that the anthropogenic influence, which is estimated by using large ensemble runs with a climate model forced with and without anthropogenic forcings, has already increased the probability of the atmospheric patterns conducive to severe haze by at least 45% in January 2013 and 27% in December 2015, respectively. We further confirm that simulated atmospheric circulation pattern changes induced by anthropogenic influence are driven mainly by increased greenhouse gas emissions. Our results suggest that more strict reductions in pollutant emissions are needed under future anthropogenic warming.

An Examination of Long-Term Environmental-Social Dynamics in the Balkans

Science.gov (United States)

Kulkarni, C.; Boger, R. A.

2015-12-01

This study examines the interactions of environmental and social dynamics in Central Balkans over the past millennium, a period that experienced three major climatic phases (Medieval Climate Anomaly, Little Ice Age, and the warm 20th century). Meanwhile, the same period witnessed a complex human history with the emergence-rise-decline of the Ottoman Empire and subsequent socio-political events (e.g. wars, famines, migrations). Environmental datasets for the analysis include biological proxies (pollen, spores, and charcoal), geochemical signals through X-ray fluorescence (XRF), and a detailed chronology based on AMS 14C dating of two western and central Serbian lakes while social datasets include historic population data, land use, settlement patterns, and critical historic events derived from a review of the literature and local archives. Among the environmental datasets, indigenous tree and herbaceous pollen from these Central Balkans records demonstrate fluctuations in woodland-grassland dynamics whereas potassium and titanium counts obtained through XRF act as a proxy for surface erosion and clastic input into the lakes. Microscopic charcoal, cereal pollen and subordinate anthropogenic pollen (e.g. cultivated fruits and vegetables) are used to distinguish strong human impact over the landscape. These key anthropogenic indicators create a more thorough social component of the analysis in association with the social datasets. After reconstructing the individual time series for each environmental and social dataset, the two Central Balkan records are correlated in order to identify the environmental and social homogeneity and heterogeneity patterns occurring at shorter and longer timescales during the period. Results provide insights on how a region responds to social and environmental stressors and our approach demonstrates ways to integrate natural and social science system research.

The evolution of the Lagoon of Venice as a paradigm of anthropogenic alteration of ecosystems: a palaeoenvironmental reconstruction through wide-area acoustic surveys and core sampling

Science.gov (United States)

Madricardo, Fantina; Donnici, Sandra

2013-04-01

The Lagoon of Venice (Italy) is the unique result of natural and anthropogenic changes. Through the centuries, human activities, steadily modified its environment, bringing it to the point that the Lagoon of Venice is itself a signature of human activities. Moreover, the historical city of Venice, a world heritage site, is threatened by flooding caused by sea level rises, so much so that major modifications of the lagoon inlets are ongoing in order to protect it. For these reasons, the Lagoon of Venice is at the same time a paradigm of a relatively circumscribed ecosystem in which the Anthropocene has started long ago, and a sensitive testbed of the environmental changes that are taking place at the global level. In this context, a large geophysical survey was carried out to explore the Holocene sediments in order to establish the natural evolution of the lagoon and the impact of human activities. The survey is the basis of an interdisciplinary study that has allowed the reconstruction of ancient landscapes of the lagoon from before its origin to present days. In particular, thanks to acoustic and geologic investigation of the lagoon sub-bottom, and by crossing our data with the environmental records provided by archaeological findings and by the city's historical archives, we could distinguish different phases of the lagoon evolution and evaluate the weight of human-induced changes We first mapped the position and the depth of the alluvial plain that was flooded during the last marine transgression, about 6000 years before present (BP), when the lagoon originated. Then, we mapped the areal extension of a dense network of palaeochannels and palaeosurfaces corresponding to different hydrological conditions and relative mean sea levels. Using many radiocarbon dating and the acoustical sub-bottom reconstruction, we could establish an average sedimentation rate of about 1 mm/year from 2500 and 1500 BP and 0.5 mm/year from 1500 BP up to present and an average migration

Landscape-scale distribution and density of raptor populations wintering in anthropogenic-dominated desert landscapes

Science.gov (United States)

Adam E. Duerr; Tricia A. Miller; Kerri L. Cornell Duerr; Michael J. Lanzone; Amy Fesnock; Todd E. Katzner

2015-01-01

Anthropogenic development has great potential to affect fragile desert environments. Large-scale development of renewable energy infrastructure is planned for many desert ecosystems. Development plans should account for anthropogenic effects to distributions and abundance of rare or sensitive wildlife; however, baseline data on abundance and distribution of such...

Heterogeneous Nucleation and Growth of Nanoparticles at Environmental Interfaces.

Science.gov (United States)

Jun, Young-Shin; Kim, Doyoon; Neil, Chelsea W

2016-09-20

Mineral nucleation is a phase transformation of aqueous components to solids with an accompanying creation of new surfaces. In this evolutional, yet elusive, process, nuclei often form at environmental interfaces, which provide remarkably reactive sites for heterogeneous nucleation and growth. Naturally occurring nucleation processes significantly contribute to the biogeochemical cycles of important components in the Earth's crust, such as iron and manganese oxide minerals and calcium carbonate. However, in recent decades, these cycles have been significantly altered by anthropogenic activities, which affect the aqueous chemistry and equilibrium of both surface and subsurface systems. These alterations can trigger the dissolution of existing minerals and formation of new nanoparticles (i.e., nucleation and growth) and consequently change the porosity and permeability of geomedia in subsurface environments. Newly formed nanoparticles can also actively interact with components in natural and engineered aquatic systems, including those posing a significant hazard such as arsenic. These interactions can bilaterally influence the fate and transport of both newly formed nanoparticles and aqueous components. Due to their importance in natural and engineered processes, heterogeneous nucleation at environmental interfaces has started to receive more attention. However, a lack of time-resolved in situ analyses makes the evaluation of heterogeneous nucleation challenging because the physicochemical properties of both the nuclei and surfaces significantly and dynamically change with time and aqueous chemistry. This Account reviews our in situ kinetic studies of the heterogeneous nucleation and growth behaviors of iron(III) (hydr)oxide, calcium carbonate, and manganese (hydr)oxide minerals in aqueous systems. In particular, we utilized simultaneous small-angle and grazing incidence small-angle X-ray scattering (SAXS/GISAXS) to investigate in situ and in real-time the effects of

Anthropogenic activities and coastal environmental quality: a regional quantitative analysis in southeast China with management implications.

Science.gov (United States)

Chen, Kai; Liu, Yan; Huang, Dongren; Ke, Hongwei; Chen, Huorong; Zhang, Songbin; Yang, Shengyun; Cai, Minggang

2018-02-01

Regional analysis of environmental issues has always been a hot topic in the field of sustainable development. Because the different levels of economic growth, urbanization, resource endowments, etc. in different regions generate apparently different ecological responses, a better description and comparison across different regions will provide more valuable implications for ecological improvement and policymaking. In this study, seven typical bays in southeast China that are a rapid developing area were selected to quantitatively analyze the relationship between socioeconomic development and coastal environmental quality. Based on the water quality data from 2007 to 2015, the multivariate statistical method was applied to analyze the potential environmental risks and to classify the seven bays based on their environmental quality status. The possible variation trends of environmental indices were predicted based on the cross-regional panel data by Environmental Kuznets Curve. The results showed that there were significant regional differences among the seven bays, especially Quanzhou, Xiamen, and Luoyuan Bays, suffered from severer artificial disturbances than other bays, despite their different development patterns. Socioeconomic development level was significantly associated with some water quality indices (pH, DIN, PO 4 -P); the association was roughly positive: the areas with higher GDP per capita have some worse water quality indices. In addition, the decreasing trend of pH values and the increasing trend of nutrient concentration in the seven bays will continue in the foreseeable future. In consideration of the variation trends, the limiting nutrient strategy should be implemented to mitigate the deterioration of the coastal environments.

Who decides who has won the bet? Total and Anthropogenic Warming Indices

Science.gov (United States)

Haustein, K.; Allen, M. R.; Otto, F. E. L.; Schmidt, A.; Frame, D. J.; Forster, P.; Matthews, D.

2016-12-01

An extension of the idea of betting markets as a means of revealing opinions about future climate are climate policies indexed to geophysical indicators: for example, to ensure net zero global carbon dioxide emissions by the time anthropogenic warming reaches 1.5 degrees above pre-industrial, given about 1 degree of warming already, emissions must fall, on average, by 20% of their current value for every tenth of a degree of anthropogenic warming from now on. In principle, policies conditioned on some measure of attributable warming are robust to uncertainty in the global climate response: the risk of a higher or lower response than expected is borne by those affected by climate change mitigation policy rather than those affected by climate change impacts, as is the case with emission targets for specific years based on "current understanding" of the response. To implement any indexed policy, or to agree payout terms for any bet on future climate, requires consensus on the definition of the index: how is it calculated, and who is responsible for releasing it? The global mean surface temperature of the current decade relative to pre-industrial may vary by 0.1 degree or more depending on precisely what is measured, what is defined as pre-industrial, and the treatment of regions with sparse data coverage in earlier years. Indices defined using different conventions, however, are all expected to evolve very similarly over the coming decades, so agreeing on a conservative, traceable index such as HadCRUT is more important than debating the "true" global temperature. A more important question is whether indexed policies and betting markets should focus on total warming, including natural and anthropogenic drivers and internal variability, or an Anthropogenic Warming Index (AWI) representing an unbiased estimate of warming attributable to human influence to date. We propose a simple AWI based solely on observed temperatures and global natural and anthropogenic forcing

Impact of Anthropogenic Factor on Urboecological Space Development

Directory of Open Access Journals (Sweden)

Kuprina Tamara

2016-01-01

Full Text Available The article discusses the issues of the impact of the anthropogenic factor on urboecological space development. The issues are considered taking into account retrospective theoretical data to show the process of Anthropoecology development as a new branch of sociological science. At present the noosphere acquires features of anthropoecosystems having a number of parameters from the endogenous and exogenous point of view. Anthropoecology has special socio-cultural significance as considers the interaction of all actors of international space. There introduced the new branch Ecopsycology as the outer world is the reflection of the inner human world. There is a definition of the sustainability of ecological system. In the practical part of the article there is an example of academic mobility as the basis of the human potential with possible transfer into the human capital supporting by survey data. In conclusion there are recommendations on management and adaptation of the anthropogenic factor (a kind of biogenesis in modern urboecological space.

Equisetum telmateia Ehrh. morphotypes related to anthropogenic habitats

Directory of Open Access Journals (Sweden)

Dominik Wróbel

2011-01-01

Full Text Available The Giant Horsetail (Equisetum telmateia is the only representative of Equisetum genus included in the list of strictly protected species. In Central and Western Europe the species is found in communities belonging to alliances: Alno-Padion and Calthion. With progressing destruction of these biotopes, one can observe the phenomenon of this species moving to the habitats extremely anthropogenic in character. Frequent and intensive observations of this phenomenon were conducted in the Jasło - Krosno Dale area in southern Poland in three anthropogenic localities. In these localities three interesting, irregular Equisetum telmateia morphotypes were found: fo. serotinum subfo. proliferum, fo. spiralis and a morphotype with branched shoot. The phenomenon of morphological plasticity of sporophytes is thought to be connected with the action of genes, which regulate the identity of developing plant organs and their distribution. These genes perform a superior part in relation to the system of growth regulators.

Anthropogenic Signatures of Lead in the Northeast Atlantic

Science.gov (United States)

Rusiecka, D.; Gledhill, M.; Milne, A.; Achterberg, E. P.; Annett, A. L.; Atkinson, S.; Birchill, A.; Karstensen, J.; Lohan, M.; Mariez, C.; Middag, R.; Rolison, J. M.; Tanhua, T.; Ussher, S.; Connelly, D.

2018-03-01

Anthropogenic activities have resulted in enhanced lead (Pb) emissions to the environment over the past century, mainly through the combustion of leaded gasoline. Here we present the first combined dissolved (DPb), labile (LpPb), and particulate (PPb) Pb data set from the Northeast Atlantic (Celtic Sea) since the phasing out of leaded gasoline in Europe. Concentrations of DPb in surface waters have decreased by fourfold over the last four decades. We demonstrate that anthropogenic Pb is transported from the Mediterranean Sea over long distances (>2,500 km). Benthic DPb fluxes exceeded the atmospheric Pb flux in the region, indicating the importance of sediments as a contemporary Pb source. A strong positive correlation between DPb, PPb, and LpPb indicates a dynamic equilibrium between the phases and the potential for particles to "buffer" the DPb pool. This study provides insights into Pb biogeochemical cycling and demonstrates the potential of Pb in constraining ocean circulation patterns.

Vegetation controls on carbon and nitrogen cycling and retention: contrasts in spruce and hardwood watershed budgets

Science.gov (United States)

Charlene N. Kelly; Stephen H. Schoenholtz; Mary Beth. Adams

2010-01-01

Anthropogenic sources of nitrogen (N) have altered the global N cycle to such an extent as to nearly double the rate of N that enters many terrestrial ecosystems. However, predicting the fate of N inputs continues to present challenges, as a multitude of environmental factors play major roles in determining N pathways. This research investigates the role of specific...

Oxidative Stress in Fish induced by Environmental Pollutants

Directory of Open Access Journals (Sweden)

Anton Kováčik

2017-05-01

Full Text Available Environmental pollutants represent a risk factor for human and animals in all areas of occurrence. Environmental pollution caused by anthropogenic activities is a major problem in many countries. Numbers of studies deals with cumulation of xenobiotics in tissues but not all respond to the real impact on living organisms. Freshwater fishes are exposed to several anthropogenic contaminants. The most commonly studied are three metals: mercury (Hg, lead (Pb, cadmium (Cd. These contaminants could have several impacts to oxidative stress. In the normal healthy cell, ROS and pro-oxidant products are detoxified by antioxidant defences. Redox-active or Redox-inactive metals may cause an increase in production of reactive oxygen species (ROS. Mercury has a high affinity for thiol groups, and can non-specifically affect several enzymes, e. g. GSH (glutathione, which can induce GSH depletion and oxidative stress in tissue, also can induce lipid peroxidation, and mitochondrial dysfunction. The toxicity of Cd to aquatic species depends on speciation, with the free ion, Cd2+ concentration being proportional to bioavailability. Cadmium toxicity worsened of Ca, Na, and Mg ions homeostasis. Lead can be toxic to nervous and skeletal systems; at cellular level can cause apoptosis, also can affect mitochondria, neurotransmitters, and can substitute for Ca.

Environmental radioactivity investigations in the Georgian subtropical region

International Nuclear Information System (INIS)

Pagava, S.; Kakashvili, P.; Avtandilashvili, M.; Kharashvili, G.; Robakidze, Z.; Rusetski, V.; Togonidze, G.; Baratashvili, D.

2002-01-01

Environmental changes in the contamination of the Georgian subtropical region have been investigated by analysing anthropogenic and natural radionuclides in samples of soil and tea leaves for possible chromosome mutations. As the tea industry in Georgia is an important economic activity, such investigations are of great importance. The changes in the morphology of tea leaves, their colour, blossoming, growth inhibition or stimulation, prolongation of the germination period and levels of tanin-katechin complexes have been investigated. The results of radionuclide measurements in soil and tea leaves ( 40 K, 210 Pb and 137 Cs) are presented. Elevated concentrations of 137 Cs were observed in soil samples due to fallout from Chernobyl, however, no direct relationship between the concentration of 137 Cs in soil and tea leaves has been observed. Cyto-genetic analyses of tea primary roots will be presented and compared for different time periods. Further, ichtyofauna samples taken from the Georgian subtropical areas were analysed for anthropogenic ( 137 Cs) and natural ( 40 K) radionuclides. The observed concentrations of 137 Cs were low, close to the detection limit of the order of 0.4 Bq/kg dry weight. Some of the investigations were carried out in the framework of the IAEA Technical Co-operation project 'Marine Environmental Assessment of the Black Sea Region'

Controlling harmful cyanobacterial blooms in a world experiencing anthropogenic and climatic-induced change

Energy Technology Data Exchange (ETDEWEB)

Paerl, Hans W., E-mail: hpaerl@email.unc.edu; Hall, Nathan S.; Calandrino, Elizabeth S.

2011-04-15

Harmful (toxic, food web altering, hypoxia generating) cyanobacterial algal blooms (CyanoHABs) are proliferating world-wide due to anthropogenic nutrient enrichment, and they represent a serious threat to the use and sustainability of our freshwater resources. Traditionally, phosphorus (P) input reductions have been prescribed to control CyanoHABs, because P limitation is widespread and some CyanoHABs can fix atmospheric nitrogen (N{sub 2}) to satisfy their nitrogen (N) requirements. However, eutrophying systems are increasingly plagued with non N{sub 2} fixing CyanoHABs that are N and P co-limited or even N limited. In many of these systems N loads are increasing faster than P loads. Therefore N and P input constraints are likely needed for long-term CyanoHAB control in such systems. Climatic changes, specifically warming, increased vertical stratification, salinization, and intensification of storms and droughts play additional, interactive roles in modulating CyanoHAB frequency, intensity, geographic distribution and duration. In addition to having to consider reductions in N and P inputs, water quality managers are in dire need of effective tools to break the synergy between nutrient loading and hydrologic regimes made more favorable for CyanoHABs by climate change. The more promising of these tools make affected waters less hospitable for CyanoHABs by 1) altering the hydrology to enhance vertical mixing and/or flushing and 2) decreasing nutrient fluxes from organic rich sediments by physically removing the sediments or capping sediments with clay. Effective future CyanoHAB management approaches must incorporate both N and P loading dynamics within the context of altered thermal and hydrologic regimes associated with climate change. - Research Highlights: {yields} Toxic cyanobacterial blooms (CyanoHABs) increasingly threaten global water supplies. {yields} Human (nutrient) and climate (hydrology, temperature) changes synergistically promote CyanoHABs. {yields

Genes Underlying Positive Influence Of Prenatal Environmental ...

African Journals Online (AJOL)

Genes Underlying Positive Influence Of Prenatal Environmental Enrichment And ... Prenatal environmental enrichment (EE) has been proven to positively affect but ... Conclusion: The negative-positive prenatal effect could contribute to altered ...

Chinese mineral dust and anthropogenic aerosol inter-continental transport: a Greenland perspective

Science.gov (United States)

Bory, A.; Abouchami, W.; Galer, S.; Svensson, A.; Biscaye, P.

2012-04-01

Impurities contained in snow and ice layers in Greenland provide a record of the history of atmospheric dustiness and pollution in the Northern Hemisphere. The source of the particles deposited onto the ice cap may be investigated using specific intrinsic tracers. Provenance discrimination may then provide valuable constraints for the validation of atmospheric transport models as well as for the monitoring of natural and anthropogenic aerosols emissions at a global scale. Clay mineralogy combined with the strontium and neodymium isotope composition of the insoluble particles extracted from recent snow deposits at NorthGRIP (75.1°N, 042.3°W), for instance, enabled us to demonstrate that the Taklimakan desert of North-western China was the main source of mineral dust reaching central Greenland at present [Bory et al., EPSL, 2002 ; GRL, 2003a]. Here we report the lead isotopic signature of these snow-pit samples, covering the 1989-1995 and 1998-2001 time periods. Unradiogenic lead isotopic composition of our Greenland samples, compared to Asian dust isotopic fingerprints, implies that most of the insoluble lead reaching the ice cap is of anthropogenic origin. Lead isotopes reveal likely contributions from European/Canadian and, to a lesser extent, US sources, as well as a marked overprinted signature typical of Chinese anthropogenic lead sources. The relative contribution of the latter appears to have been increasing steadily over the last decade of the 20th century. Quantitative estimates suggest that, in addition to providing most of the dust, China may have already become the most important supplier of anthropogenic lead deposited in Greenland by the turn of the 20th to the 21st century. The close timing between dust and anthropogenic particles deposition onto the ice cap provides new insights for our understanding of Chinese aerosols transport to Greenland.

Detecting the anthropogenic influences on recent changes in ocean carbon uptake

International Nuclear Information System (INIS)

Seferian, Roland; Ribes, Aurelien; Bopp, Laurent

2014-01-01

Anthropogenic greenhouse gas emissions have modified the rate at which oceans have absorbed atmospheric CO 2 over the last centuries through rising atmospheric CO 2 and modifications in climate. However, there are still missing pieces in our understanding of the recent evolution of air-sea CO 2 exchanges related to the magnitude of their response to anthropogenic forcing versus that controlled by the internal variability. Here, to detect and attribute anthropogenic influences on oceanic CO 2 uptake between 1960 and 2005, we compare an ensemble of Coupled Model Intercomparison Project Phase 5 (CMIP5) climate model simulations forced by individual drivers to ocean-only model reconstructions. We demonstrate that the evolution of the global oceanic carbon sink over the last decades can be understood without invoking climate change, attributing rising atmospheric CO 2 as prominent driver of the oceanic sink. Nonetheless, at regional scale, the influence of climate change on air-sea CO 2 exchanges seems to emerge from the internal variability within the low-latitude oceans. (authors)

Stable nitrogen isotopes in coastal macroalgae: Geographic and anthropogenic variability

International Nuclear Information System (INIS)

Viana, Inés G.; Bode, Antonio

2013-01-01

Growing human population adds to the natural nitrogen loads to coastal waters. Both anthropogenic and natural nitrogen is readily incorporated in new biomass, and these different nitrogen sources may be traced by the measurement of the ratio of stable nitrogen isotopes (δ 15 N). In this study δ 15 N was determined in two species of macroalgae (Ascophyllum nodosum and Fucus vesiculosus), and in nitrate and ammonium to determine the relative importance of anthropogenic versus natural sources of nitrogen along the coast of NW Spain. Both algal species and nitrogen sources showed similar isotopic enrichment for a given site, but algal δ 15 N was not related to either inorganic nitrogen concentrations or δ 15 N in the water samples. The latter suggests that inorganic nitrogen inputs are variable and do not always leave an isotopic trace in macroalgae. However, a significant linear decrease in macroalgal δ 15 N along the coast is consistent with the differential effect of upwelling. Besides this geographic variability, the influence of anthropogenic nitrogen sources is evidenced by higher δ 15 N in macroalgae from rias and estuaries compared to those from open coastal areas and in areas with more than 15 × 10 3 inhabitants in the watershed. These results indicate that, in contrast with other studies, macroalgal δ 15 N is not simply related to either inorganic nitrogen concentrations or human population size but depends on other factors as the upwelling or the efficiency of local waste treatment systems. - Highlights: ► Anthropogenic versus upwelling nitrogen effect on macroalgal δ 15 N was studied. ► The influence of populations and upwelling has not been made before on macroalgal δ 15 N. ► Natural variability has not been taken into account in most biomonitoring studies. ► Upwelling explains most of the variability in δ 15 N in macroalgae

Hyperspectral observation of anthropogenic and biogenic pollution in coastal zone

Science.gov (United States)

Lavrova, Olga; Loupian, Evgeny; Mityagina, Marina; Uvarov, Ivan

The work presents results of anthropogenic and biogenic pollution detection in coastal zones of the Black and Caspian Seas based on satellite hyperspetral data provided by the Hyperion and HICO instruments. Techniques developed on the basis of the analysis of spectral characteristics calculated in special points were employed to address the following problems: (a) assessment of the blooming intensity of cyanobacteria and their distribution in bays of western Crimea and discrimination between anthropogenic pollutant discharge events and algae bloom; (b) detection of anthropogenic pollution in Crimean lakes utilized as industrial liquid discharge reservoirs; (c) detection of oil pollution in areas of shelf oil production in the Caspian Sea. Information values of different spectral bands and their composites were estimated in connection with the retrieval of the main sea water components: phytoplankton, suspended matter and colored organic matter, and also various anthropogenic pollutants, including oil. Software tools for thematic hyperspectral data processing in application to the investigation of sea coastal zones and internal water bodies were developed on the basis of the See the Sea geoportal created by the Space Research Institute RAS. The geoportal is focused on the study of processes in the world ocean with the emphasis on the advantages of satellite systems of observation. The tools that were introduced into the portal allow joint analysis of quasi-simultaneous satellite data, in particular data from the Hyperion, HICO, OLI Landsat-8, ETM Landsat-7 and TM Landsat-5 instruments. Results of analysis attempts combining data from different sensors are discussed. Their strong and weak points are highlighted. The study was completed with partial financial support from The Russian Foundation for Basic Research grants # 14-05-00520-a and 13-07-12017.

Use of alligator hole abundance and occupancy rate as indicators for restoration of a human-altered wetland

Science.gov (United States)

Fujisaki, Ikuko; Mazzotti, Frank J.; Hart, Kristen M.; Rice, Kenneth G.; Ogurcak, Danielle; Rochford, Michael; Jeffery, Brian M.; Brandt, Laura A.; Cherkiss, Michael S.

2012-01-01

Use of indicator species as a measure of ecosystem conditions is an established science application in environmental management. Because of its role in shaping wetland systems, the American alligator (Alligator mississippiensis) is one of the ecological indicators for wetland restoration in south Florida, USA. We conducted landscape-level aerial surveys of alligator holes in two different habitats in a wetland where anthropogenic modification of surface hydrology has altered the natural system. Alligator holes were scarcer in an area where modified hydrology caused draining and frequent dry-downs compared to another area that maintains a functional wetland system. Lower abundance of alligator holes indicates lack of alligator activities, lower overall species diversity, and lack of dry-season aquatic refugia for other organisms. The occupancy rate of alligator holes was lower than the current restoration target for the Everglades, and was variable by size class with large size-class alligators predominantly occupying alligator holes. This may indicate unequal size-class distribution, different habitat selection by size classes, or possibly a lack of recruitment. Our study provides pre-restoration baseline information about one indicator species for the Everglades. Success of the restoration can be assessed via effective synthesis of information derived by collective research efforts on the entire suite of selected ecological indicators.

″The Anthropocene″, Ecosystem Management, and Environmental Virtue.

Science.gov (United States)

Sandler, Ronald

2016-01-01

*Portions of this article are drawn from: Sandler, R. Environmental Ethics: Theory in Practice, Oxford University Press, New York, in press. In this article I consider contrasting views on the implications of rapid, macroscale anthropogenic change for environmental ethics, particularly ecosystem management, species conservation, and environmental virtue. I begin by reviewing the Anthropocene debate, which has become a primary point of discourse on whether we ought to embrace a more interventionist stance regarding ecosystem management and species conservation. I then discuss the challenges posed by rapid ecological change to predominant ecosystem management and species conservation practices. I argue that these challenges not withstanding, we ought not go all in on interventionist management, even as novel conservation and management techniques can be justified in particular cases. It is possible to adopt a more forward looking normative stance, without licensing robust interventionism. Finally, I discuss the implications of this for some environmental virtues.

Evaluating Anthropogenic Risk of Grassland and Forest Habitat Degradation using Land-Cover Data

Directory of Open Access Journals (Sweden)

Kurt Riitters

2009-09-01

Full Text Available The effects of landscape context on habitat quality are receiving increased attention in conservation biology. The objective of this research is to demonstrate a landscape-level approach to mapping and evaluating the anthropogenic risks of grassland and forest habitat degradation by examining habitat context as defined by intensive anthropogenic land uses at multiple spatial scales. A landscape mosaic model classifies a given location according to the amounts of intensive agriculture and intensive development in its surrounding landscape, providing measures of anthropogenic risks attributable to habitat isolation and edge effects at that location. The model is implemented using a land-cover map (0.09 ha/pixel of the conterminous United States and six landscape sizes (4.4, 15.2, 65.6, 591, 5300, and 47800 ha to evaluate the spatial scales of anthropogenic risk. Statistics for grassland and forest habitat are extracted by geographic overlays of the maps of land-cover and landscape mosaics. Depending on landscape size, 81 to 94 percent of all grassland and forest habitat occurs in landscapes that are dominated by natural land-cover including habitat itself. Within those natural-dominated landscapes, 50 percent of grassland and 59 percent of forest is within 590 m of intensive agriculture and/or intensive developed land which is typically a minor component of total landscape area. The conclusion is that anthropogenic risk attributable to habitat patch isolation affects a small proportion of the total grassland or forest habitat area, while the majority of habitat area is exposed to edge effects.

Quantifying Anthropogenic Stress on Groundwater Resources.

Science.gov (United States)

Ashraf, Batool; AghaKouchak, Amir; Alizadeh, Amin; Mousavi Baygi, Mohammad; R Moftakhari, Hamed; Mirchi, Ali; Anjileli, Hassan; Madani, Kaveh

2017-10-10

This study explores a general framework for quantifying anthropogenic influences on groundwater budget based on normalized human outflow (h out ) and inflow (h in ). The framework is useful for sustainability assessment of groundwater systems and allows investigating the effects of different human water abstraction scenarios on the overall aquifer regime (e.g., depleted, natural flow-dominated, and human flow-dominated). We apply this approach to selected regions in the USA, Germany and Iran to evaluate the current aquifer regime. We subsequently present two scenarios of changes in human water withdrawals and return flow to the system (individually and combined). Results show that approximately one-third of the selected aquifers in the USA, and half of the selected aquifers in Iran are dominated by human activities, while the selected aquifers in Germany are natural flow-dominated. The scenario analysis results also show that reduced human withdrawals could help with regime change in some aquifers. For instance, in two of the selected USA aquifers, a decrease in anthropogenic influences by ~20% may change the condition of depleted regime to natural flow-dominated regime. We specifically highlight a trending threat to the sustainability of groundwater in northwest Iran and California, and the need for more careful assessment and monitoring practices as well as strict regulations to mitigate the negative impacts of groundwater overexploitation.

Time Factor in the Theory of Anthropogenic Risk Prediction in Complex Dynamic Systems

Science.gov (United States)

Ostreikovsky, V. A.; Shevchenko, Ye N.; Yurkov, N. K.; Kochegarov, I. I.; Grishko, A. K.

2018-01-01

The article overviews the anthropogenic risk models that take into consideration the development of different factors in time that influence the complex system. Three classes of mathematical models have been analyzed for the use in assessing the anthropogenic risk of complex dynamic systems. These models take into consideration time factor in determining the prospect of safety change of critical systems. The originality of the study is in the analysis of five time postulates in the theory of anthropogenic risk and the safety of highly important objects. It has to be stressed that the given postulates are still rarely used in practical assessment of equipment service life of critically important systems. That is why, the results of study presented in the article can be used in safety engineering and analysis of critically important complex technical systems.

Attributing Changing Rates of Temperature Record Breaking to Anthropogenic Influences

Science.gov (United States)

King, Andrew D.

2017-11-01

Record-breaking temperatures attract attention from the media, so understanding how and why the rate of record breaking is changing may be useful in communicating the effects of climate change. A simple methodology designed for estimating the anthropogenic influence on rates of record breaking in a given time series is proposed here. The frequency of hot and cold record-breaking temperature occurrences is shown to be changing due to the anthropogenic influence on the climate. Using ensembles of model simulations with and without human-induced forcings, it is demonstrated that the effect of climate change on global record-breaking temperatures can be detected as far back as the 1930s. On local scales, a climate change signal is detected more recently at most locations. The anthropogenic influence on the increased occurrence of hot record-breaking temperatures is clearer than it is for the decreased occurrence of cold records. The approach proposed here could be applied in rapid attribution studies of record extremes to quantify the influence of climate change on the rate of record breaking in addition to the climate anomaly being studied. This application is demonstrated for the global temperature record of 2016 and the Central England temperature record in 2014.

Exploring associations between international trade and environmental factors with establishment patterns of exotic Scolytinae

Science.gov (United States)

Lorenzo Marini; Robert A. Haack; Robert J. Rabaglia; Edoardo Petrucco Toffolo; Andrea Battisti; Massimo Faccoli

2011-01-01

Although invasion of exotic ambrosia beetles (fungus feeders) and bark beetles (phloem feeders) (Coleoptera: Curculionidae: Scolytinae) is considered a major threat to forest health worldwide, no studies have quantitatively investigated the anthropogenic and environmental factors shaping the biogeographical patterns of invasion by these insects across large spatial...

Heavy metals anthropogenic pollutants in Austria

International Nuclear Information System (INIS)

Anderl, M.; Gager, M.; Gugele, B.; Huttunen, K.; Kurzweil, A.; Poupa, S.; Ritter, M.; Wappel, D.; Wieser, M.

2004-01-01

Several heavy metals from anthropogenic sources are emitted in the atmosphere damaging the air quality and the human health, besides they accumulate on the soil and lately are transmitted into the human food chain. Therefore at international level there is a concern to reduce them. Austrian heavy metals emissions (cadmium, mercury and lead) during 1990-2002 are given including an analysis of causes and sources. Lead is the main pollutant and the main sector responsible is the industry. 5 figs. (nevyjel)

Historical economic and environmental policies influencing trace metal inputs in Montevideo Bay, Río de la Plata

International Nuclear Information System (INIS)

Bueno, C.; Brugnoli, E.; Figueira, R.C.L.; Muniz, P.; Ferreira, P.A.L.

2016-01-01

Montevideo Bay is located in the middle zone of the Rio de la Plata, and since the foundation of the city, several key economic and environmental policies affected the industry, and thus, metal inputs into this ecosystem. The aim of this study is to evaluate the sedimentary geochemical record of Montevideo Bay, in order to determine the historical inputs of anthropogenic metals to the system. In addition, environmental and economic policies of the country were taken into account to infer the relationship between them and the historic metal input. Concentrations of aluminum, chromium, copper, lead, scandium and zinc were analyzed and the EF and SPI indices were calculated. The analysis showed that since Montevideo foundation, metal concentrations increased in accordance with industry development, and the indices as well as the metal concentration represent a reliable footprint of the history of different economic and environmental policies influencing historical industrial activities. - Highlights: • Trace metal record of a sediment core of Montevideo Bay/harbor was studied. • The historic inputs of metals in the area were inferred. • System degradation evolved from anthropogenic impacts. • A relationship between pollution and environmental/economic policies was discussed.

[From environmental ethics to environmental bioethics: antecedents, trajectories, and perspectives].

Science.gov (United States)

Fischer, Marta Luciane; Cunha, Thiago; Renk, Valquiria; Sganzerla, Anor; Santos, Juliana Zacarkin Dos

2017-01-01

The relationship between humans and the environment became an ethical problem in the twentieth century, when accelerated economic and scientific development was accompanied by profound alterations in global ecological systems. In response, environmental ethics called for limits in the dichotomous relationship between man and nature. In 1970, Van Potter proposed bioethics as the interdisciplinary study of "human survival." Subsequently, the discipline focused on clinical and hospital conflicts. Environmental bioethics is analyzed in this article as a theoretical perspective that has historically drawn on Van Potter's approach to bioethics, marked by the interpersonal, socioeconomic, and political dimensions of environmental ethical dilemmas.

Rapid Assessment of Anthropogenic Impacts of Exposed Sandy ...

African Journals Online (AJOL)

We applied a rapid assessment methodology to estimate the degree of human impact of exposed sandy beaches in Ghana using ghost crabs as ecological indicators. The use of size ranges of ghost crab burrows and their population density as ecological indicators to assess extent of anthropogenic impacts on beaches ...

Soil Organic Matter Responses to Anthropogenic Forest Disturbance and Land Use Change in the Eastern Brazilian Amazon

Directory of Open Access Journals (Sweden)

Mariana Regina Durigan

2017-03-01

Full Text Available Anthropogenic forest disturbance and land use change (LUC in the Amazon region is the main source of greenhouse gas emissions to the atmosphere in Brazil, due to the carbon (C and nitrogen (N emitted from vegetation clearance. Land use conversion associated with management practices plays a key role in the distribution and origin of C in different soil organic matter (SOM fractions. Here, we show how changing land use systems have influenced soil C and N stocks, SOM physical fractions, and the origin of SOM in the Santarém region of the eastern Brazilian Amazon. Soil C and N stocks were calculated for the surface layer of 0–30 cm. Anthropogenic disturbances to the standing forest, such as selective logging and wildfires, led to significant declines in soil C and N stocks. However, in the long-term, the conversion of the Amazon forest to pasture did not have a noticeable effect on soil C and N stocks, presumably because of additional inputs from pasture grasses. However, the conversion to cropland did lead to reductions in soil C and N content. According to the physical fractionation of SOM, LUC altered SOM quality, but silt and clay remained the combined fraction that contributed the most to soil C storage. Our results emphasize the importance of implementing more sustainable forest management systems, whilst also calling further attention to the need for fire monitoring systems, helping to ensure the resilience of C and N stocks and sequestration in forest soils; thereby contributing towards urgently needed ongoing efforts to mitigate climate change.

Iodine isotopes species fingerprinting environmental conditions in surface water along the northeastern Atlantic Ocean

DEFF Research Database (Denmark)

He, Peng; Hou, Xiaolin; Aldahan, Ala

2013-01-01

Concentrations and species of iodine isotopes (127I and 129I) provide vital information about iodine geochemistry, environmental conditions and water masses exchange in oceans. Despite extensive investigations of anthropogenic 129I in the Arctic Ocean and the Nordic Seas, concentrations of the is...... 129I in ocean environments and impact on climate at the ocean boundary layer.......Concentrations and species of iodine isotopes (127I and 129I) provide vital information about iodine geochemistry, environmental conditions and water masses exchange in oceans. Despite extensive investigations of anthropogenic 129I in the Arctic Ocean and the Nordic Seas, concentrations...... of the isotope in the Atlantic Ocean are, however, still unknown. We here present first data on 129I and 127I, and their species (iodide and iodate) in surface water transect along the northeastern Atlantic between 30° and 50°N. The results show iodate as the predominant species in the analyzed marine waters...

Anthropogenic mortality on coral reefs in Caribbean Panama predates coral disease and bleaching.

Science.gov (United States)

Cramer, Katie L; Jackson, Jeremy B C; Angioletti, Christopher V; Leonard-Pingel, Jill; Guilderson, Thomas P

2012-06-01

Caribbean reef corals have declined precipitously since the 1980s due to regional episodes of bleaching, disease and algal overgrowth, but the extent of earlier degradation due to localised historical disturbances such as land clearing and overfishing remains unresolved. We analysed coral and molluscan fossil assemblages from reefs near Bocas del Toro, Panama to construct a timeline of ecological change from the 19th century-present. We report large changes before 1960 in coastal lagoons coincident with extensive deforestation, and after 1960 on offshore reefs. Striking changes include the demise of previously dominant staghorn coral Acropora cervicornis and oyster Dendrostrea frons that lives attached to gorgonians and staghorn corals. Reductions in bivalve size and simplification of gastropod trophic structure further implicate increasing environmental stress on reefs. Our paleoecological data strongly support the hypothesis, from extensive qualitative data, that Caribbean reef degradation predates coral bleaching and disease outbreaks linked to anthropogenic climate change. © 2012 Blackwell Publishing Ltd/CNRS.

The soil organic carbon content of anthropogenically altered organic soils effects the dissolved organic matter quality, but not the dissolved organic carbon concentrations

Science.gov (United States)

Frank, Stefan; Tiemeyer, Bärbel; Bechtold, Michel; Lücke, Andreas; Bol, Roland

2016-04-01

Dissolved organic carbon (DOC) is an important link between terrestrial and aquatic ecosystems. This is especially true for peatlands which usually show high concentrations of DOC due to the high stocks of soil organic carbon (SOC). Most previous studies found that DOC concentrations in the soil solution depend on the SOC content. Thus, one would expect low DOC concentrations in peatlands which have anthropogenically been altered by mixing with sand. Here, we want to show the effect of SOC and groundwater level on the quantity and quality of the dissolved organic matter (DOM). Three sampling sites were installed in a strongly disturbed bog. Two sites differ in SOC (Site A: 48%, Site B: 9%) but show the same mean annual groundwater level of 15 and 18 cm below ground, respectively. The SOC content of site C (11%) is similar to Site B, but the groundwater level is much lower (-31 cm) than at the other two sites. All sites have a similar depth of the organic horizon (30 cm) and the same land-use (low-intensity sheep grazing). Over two years, the soil solution was sampled bi-weekly in three depths (15, 30 and 60 cm) and three replicates. All samples were analyzed for DOC and selected samples for dissolved organic nitrogen (DON) and delta-13C and delta-15N. Despite differences in SOC and groundwater level, DOC concentrations did not differ significantly (A: 192 ± 62 mg/L, B: 163 ± 55 mg/L and C: 191 ± 97 mg/L). At all sites, DOC concentrations exceed typical values for peatlands by far and emphasize the relevance even of strongly disturbed organic soils for DOC losses. Individual DOC concentrations were controlled by the temperature and the groundwater level over the preceding weeks. Differences in DOM quality were clearer. At site B with a low SOC content, the DOC:DON ratio of the soil solution equals the soil's C:N ratio, but the DOC:DON ratio is much higher than the C:N ratio at site A. In all cases, the DOC:DON ratio strongly correlates with delta-13C. There is no

Monitoring adaptive genetic responses to environmental change

DEFF Research Database (Denmark)

Hansen, M.M.; Olivieri, I.; Waller, D.M.

2012-01-01

Widespread environmental changes including climate change, selective harvesting and landscape alterations now greatly affect selection regimes for most organisms. How animals and plants can adapt to these altered environments via contemporary evolution is thus of strong interest. We discuss how...... for selection and establishing clear links between genetic and environmental change. We then review a few exemplary studies that explore adaptive responses to climate change in Drosophila, selective responses to hunting and fishing, and contemporary evolution in Daphnia using resurrected resting eggs. We...

Holocene environmental and parasequence development of the St. Jones Estuary, Delaware (USA): Foraminiferal proxies of natural climatic and anthropogenic change

Science.gov (United States)

Leorri, E.; Martin, R.; McLaughlin, P.

2006-01-01

The benthic foraminiferal record of marshes located along western Delaware Bay (St. Jones Estuary, USA) reflects the response of estuaries to sea-level and paleoclimate change during the Holocene. System tracts are recognized and within them parasequences based on sedimentological and foraminiferal assemblages identification. The parasequences defined by foraminiferal assemblages appear correlative with rapid Holocene climate changes that are of worldwide significance: 6000-5000, 4200-3800, 3500-2500, 1200-1000, and 600??cal years BP. Following postglacial sea-level rise, modern subestuaries and marshes in the region began to develop between 6000 and 4000??years BP, depending on their proximity to the mouth of Delaware Bay and coastal geomorphology. Initial sediments were fluvial in origin, with freshwater marshes established around 4000??years BP. The subsequent sea-level transgression occurred sufficiently slowly that freshwater marshes alternated with salt marshes at the same sites to around 3000??years BP. Locally another two transgressions are identified at 1800 and 1000??years BP respectively. Marine influence increased in the estuaries until 600??years BP (Little Ice Age), when regression occurred. Sea-level began to rise again during the mid-19th Century at the end of the Little Ice Age, when marshes became established. The presence of a sand lens in the upper and middle estuary and the reduction in the number of tests in the top samples in cores from the same area also suggest an anthropogenic influence. The estuary infill resulted in a sharp transgressive sequence, represented by salt marsh foraminiferal assemblages in the upper part of the cores. The increase in marsh foraminifera in both areas suggests an increase in marine influence that might be due to the transgression beginning at the end of the Little Ice Age about 150-180??years ago coupled with anthropogenic straightening of the channel in 1913. ?? 2006 Elsevier B.V. All rights reserved.

Simulations of the global carbon cycle and anthropogenic CO{sub 2} transient. Annual report

Energy Technology Data Exchange (ETDEWEB)

Sarmiento, J.L.

1994-07-01

This research focuses on improving the understanding of the anthropogenic carbon dioxide transient using observations and models of the past and present. In addition, an attempt is made to develop an ability to predict the future of the carbon cycle in response to continued anthropogenic perturbations and climate change. Three aspects of the anthropogenic carbon budget were investigated: (1) the globally integrated budget at the present time; (2) the time history of the carbon budget; and (3) the spatial distribution of carbon fluxes. One of the major activities of this study was the participation in the model comparison study of Enting, et al. [1994] carried out in preparation for the IPCC 1994 report.

The disturbance-diversity relationship: integrating biodiversity conservation and resource management in anthropogenic landscapes

OpenAIRE

Sharma, Lila Nath

2016-01-01

Disturbance, natural or anthropogenic, is ubiquitous to forest and grassland ecosystems across the globe. Many of these ecosystems have evolved alongside centuries old anthropogenic disturbance regimes. Understanding how disturbance impacts biodiversity and ecosystem service delivery is a topic of paramount importance as high biodiversity is likely to provide a wide array of ecosystem goods and services to an ever-growing human population. There is a general consensus that dist...

Environmental perverse incentives in coastal monitoring.

Science.gov (United States)

Gibbs, Mark T

2013-08-15

It can be argued that the intensity of monitoring of coastal marine environments lags behind the equivalent terrestrial environments. This results in a paucity of long-term time series of key environmental parameters such as turbidity. This lack of management information of the sources and sinks, and causes and impacts of stressors to the coastal marine environment, along with a lack of co-ordination of information collection is compromising the ability of environmental impact assessments of major coastal developments to discriminate between local and remote anthropogenic impacts, and natural or background processes. In particular, the quasi outsourcing of the collection of coastal information can lead to a perverse incentive whereby in many cases nobody is actively or consistently monitoring the coastal marine environment effectively. This is particularly the case with regards to the collection of long-term and whole-of-system scale data. This lack of effective monitoring can act to incentivise poor environmental performance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fluctuations in coral health of four common inshore reef corals in response to seasonal and anthropogenic changes in water quality.

Science.gov (United States)

Browne, Nicola K; Tay, Jason K L; Low, Jeffrey; Larson, Ole; Todd, Peter A

2015-04-01

Environmental drivers of coral condition (maximum quantum yield, symbiont density, chlorophyll a content and coral skeletal growth rates) were assessed in the equatorial inshore coastal waters of Singapore, where the amplitude of seasonal variation is low, but anthropogenic influence is relatively high. Water quality variables (sediments, nutrients, trace metals, temperature, light) explained between 52 and 83% of the variation in coral condition, with sediments and light availability as key drivers of foliose corals (Merulina ampliata, Pachyseris speciosa), and temperature exerting a greater influence on a branching coral (Pocillopora damicornis). Seasonal reductions in water quality led to high chlorophyll a concentrations and maximum quantum yields in corals, but low growth rates. These marginal coral communities are potentially vulnerable to climate change, hence, we propose water quality thresholds for coral growth with the aim of mitigating both local and global environmental impacts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Artificial light alters natural regimes of night-time sky brightness

Science.gov (United States)

Davies, Thomas W.; Bennie, Jonathan; Inger, Richard; Gaston, Kevin J.

2013-01-01

Artificial light is globally one of the most widely distributed forms of anthropogenic pollution. However, while both the nature and ecological effects of direct artificial lighting are increasingly well documented, those of artificial sky glow have received little attention. We investigated how city lights alter natural regimes of lunar sky brightness using a novel ten month time series of measurements recorded across a gradient of increasing light pollution. In the city, artificial lights increased sky brightness to levels six times above those recorded in rural locations, nine and twenty kilometers away. Artificial lighting masked natural monthly and seasonal regimes of lunar sky brightness in the city, and increased the number and annual regime of full moon equivalent hours available to organisms during the night. The changes have potentially profound ecological consequences.

Benthic Foraminifera as bio-indicators of anthropogenic impacts in coastal environments: Acqua dei Corsari area case study (Palermo, Italy).

Science.gov (United States)

Musco, Marianna; Cuttitta, Angela; Bicchi, Erica; Quinci, Enza Maria; Sprovieri, Mario; Tranchida, Giorgio; Giaramita, Luigi; Traina, Anna; Salvagio Manta, Daniela; Gherardi, Serena; Mercurio, Pietro; Siragusa, Angelo; Mazzola, Salvatore

2017-04-15

This study investigates living benthic foraminiferal assemblages as bio-indicators of anthropogenic activities in a coastal area within the Gulf of Palermo (Sicily, Italy), affected by industrial and urban activities, and evaluates the environmental quality through the calibration of a Tolerant Species index (%TS std ). Sediments from 6 stations were sampled along a bathymetric transect from the coast to offshore. Sediment grain size, TOC, major, minor and trace elements and polycyclic aromatic hydrocarbons (PAHs) were compared to benthic foraminiferal assemblages and species at each station. Diversity and density of benthic foraminiferal assemblages were not affected by the presence of pollutants, while tolerant species increased with organic (TOC and PAHs) or chemical (As and Pb) concentrations. Moreover, the calibration of the %TS std formula to >125μm foraminiferal assemblage, gives a detailed description of environmental quality along the transect, representing a good and sensitive tool to evaluate marine coastal environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modeling Agassiz's Desert Tortoise Population Response to Anthropogenic Stressors

Science.gov (United States)

Mojave Desert tortoise (Gopherus agassizii) populations are exposed to a variety of anthropogenic threats, which vary in nature, severity, and frequency. Tortoise management in conservation areas can be compromised when the relative importance of these threats is not well underst...

Issues and options in addressing the environmental consequences of livestock sector's growth.

Science.gov (United States)

Gerber, P J; Vellinga, T V; Steinfeld, H

2010-02-01

The growth of the livestock sector is being achieved at substantial environmental costs. Today, livestock are a major stressor of the global environmental, occupying a quarter of emerged land (including a third of arable land), contributing close to a fifth of the anthropogenic greenhouse gas emissions, using eight percent of all water resources and threatening a wide range of endangered species. At the same time, livestock are also a crucial engine of rural growth and a tool for improving food security. Policies are required to guide the sector in achieving sometimes conflicting development objectives. Potential pathways include encouraging resource use efficiency, correcting for environmental externalities and accelerating technological change.

Coral reef degradation and metabolic performance of the scleractinian coral Porites lutea under anthropogenic impact along the NE coast of Hainan Island, South China Sea

KAUST Repository

Roder, Cornelia; Wu, Zhongjie; Richter, Claudio; Zhang, Jing

2013-01-01

Hainan's coast provides favorable climatic, geochemical and biogeographic conditions for the development of extensive coral reefs in China. Observations in five reefs along the NE coast of Hainan showed, however, that the overall density of mobile macrofauna is low and key functional groups such as browsing, scraping or excavating herbivore fish are missing altogether. Coral diseases, partial mortality or tissue degradation are abundant and growth of macroalgal space competitors extensive. Signs of eutrophication, siltation and destructive fishing practices are evident resulting in a strongly altered environment unfavorable for coral recruitment success and survival. Acclimation to the anthropogenically altered conditions in the massive coral Porites lutea occurs at the cost of a decreased photosynthesis: respiration ratio reducing the regenerative capacity of these key framebuilding organisms. Even though, on the organismal level, corals are able to cope with these stressful conditions, a shift is imminent on the ecosystem level from a coral reef to a macroalgae-dominated community if land-based disturbance prevails unabated. © 2012 Elsevier Ltd.

Coral reef degradation and metabolic performance of the scleractinian coral Porites lutea under anthropogenic impact along the NE coast of Hainan Island, South China Sea

KAUST Repository

Roder, Cornelia

2013-04-01

Hainan\\'s coast provides favorable climatic, geochemical and biogeographic conditions for the development of extensive coral reefs in China. Observations in five reefs along the NE coast of Hainan showed, however, that the overall density of mobile macrofauna is low and key functional groups such as browsing, scraping or excavating herbivore fish are missing altogether. Coral diseases, partial mortality or tissue degradation are abundant and growth of macroalgal space competitors extensive. Signs of eutrophication, siltation and destructive fishing practices are evident resulting in a strongly altered environment unfavorable for coral recruitment success and survival. Acclimation to the anthropogenically altered conditions in the massive coral Porites lutea occurs at the cost of a decreased photosynthesis: respiration ratio reducing the regenerative capacity of these key framebuilding organisms. Even though, on the organismal level, corals are able to cope with these stressful conditions, a shift is imminent on the ecosystem level from a coral reef to a macroalgae-dominated community if land-based disturbance prevails unabated. © 2012 Elsevier Ltd.

Strategic environmental assessment can help solve environmental impact assessment failures in developing countries

International Nuclear Information System (INIS)

Alshuwaikhat, Habib M.

2005-01-01

The current trend of industrialization and urbanization in developing nations has a huge impact on anthropogenic and natural ecosystems. Pollution sources increase with the expansion of cities and cause contamination of water, air and soil. The absence of urban environmental planning and management strategies has resulted in greater concern for future urban development. This paper advocates the adoption of strategic environmental assessment (SEA) as a means to achieve sustainable development in developing countries. It investigates project-level environmental impact assessment (EIA) and its limitations. The exploration of SEA and its features are addressed. The effective implementation of SEA can create a roadmap for sustainable development. In many developing countries, the lack of transparency and accountability and ineffective public participation in the development of the policy, plan and program (PPP) would be mitigated by the SEA process. Moreover, the proactive and broadly based characteristics of SEA would benefit the institutional development of the PPP process, which is rarely experienced in many developing countries. The paper also explores the prospects for SEA and its guiding principles in developing countries. Finally, the paper calls for a coordinated effort between all government, nongovernment and international organizations involved with PPPs to enable developing countries to pursue a path of sustainable development through the development and application of strategic environmental assessment

World-wide anthropogenic climate changes: facts, uncertainties and open questions

International Nuclear Information System (INIS)

Schoenwiese, C.D.

1994-01-01

Various human activities are, without a doubt, leading to a steady increase world-wide in the emissions of trace gases which affect the climate into the atmosphere. As a result, the global climate is also forced to change. The evidence from climate models regarding this is uncertain, however, both with respect to the quantitative aspect and the regional aspect, especially concerning climatic elements apart from temperature. It is therefore important to examine the data of climate history for anthropogenic climate signals. It is difficult, though, to distinguish between natural and anthropogenic climate effects. Despite these uncertainties, however, which result in many questions remaining open, estimations of risk and the principle of responsibility lead to immediate, international climate protection measures being demanded. (orig.) [de

Characterizing the Status (Disturbed, Hybrid or Novel) of Swamp Forest Fragments in a Caribbean Ramsar Wetland: The Impact of Anthropogenic Degradation and Invasive Plant Species.

Science.gov (United States)

Prospere, Kurt; McLaren, Kurt P; Wilson, Byron

2016-10-01

The last remaining Amazonian-type swamp forest fragments in Black River Lower Morass, Jamaica, have been subjected to a myriad of anthropogenic disturbances, compounded by the establishment and spread of several invasive plant species. We established 44 permanent sample plots (covering 3.92 ha) across 10 of these swamp forest fragments and sampled all non-woody plants and all trees ≥2 cm DBH found in the plots. These data were used to (1) identify thresholds of hybridity and novelty, (2) derive several diversity and structural descriptors used to characterize the swamp forest fragments and (3) identify possible indicators of anthropogenic degradation. These were incorporated into a framework and used to determine the status of the swamp forest fragments so that appropriate management and conservation measures can be implemented. We recorded 43 woody plant species (9 endemic, 28 native and 4 non-native) and 21 non-tree species. The composition and structure of all the patches differed significantly due to the impact of the herbaceous invasive plant Alpinia allughas, the presence and diversity of other non-native plants, and differing intensities of anthropogenic disturbance (e.g., burning, cutting and harvesting of non-timber forest products). We ranked forest patches along a continuum representing deviations from a historical proxy (least disturbed) swamp forest to those with dramatically altered structural and floristic attributes (=novel swamp forests). Only one fragment overrun with A. allughas was classified as novel. If effective conservation and management does not come to the BRLM, the remaining swamp forest fragments appear doomed to further degradation and will soon disappear altogether.

Why nuclear energy is essential to reduce anthropogenic greenhouse gas emission rates

International Nuclear Information System (INIS)

Alonso, A.; Brook, B.W.; Meneley, D.A.; Misak, J.; Blees, T.; Van Erp, J.B.

2015-01-01

Reduction of anthropogenic greenhouse gas emissions is advocated by the Intergovernmental Panel on Climate Change. To achieve this target, countries have opted for renewable energy sources, primarily wind and solar. These renewables will be unable to supply the needed large quantities of energy to run industrial societies sustainably, economically and reliably because they are inherently intermittent, depending on flexible backup power or on energy storage for delivery of base-load quantities of electrical energy. The backup power is derived in most cases from combustion of natural gas. Intermittent energy sources, if used in this way, do not meet the requirements of sustainability, nor are they economically viable because they require redundant, under- utilized investment in capacity both for generation and for transmission. Because methane is a potent greenhouse gas, the equivalent carbon dioxide value of methane may cause gas-fired stations to emit more greenhouse gas than coal-fired plants of the same power for currently reported leakage rates of the natural gas. Likewise, intermittent wind/solar photovoltaic systems backed up by gas-fu:ed power plants also release substantial amounts of carbon-dioxide- equivalent greenhouse gas to make such a combination environmentally unacceptable. In the long term, nuclear fission technology is the only known energy source that is capable of delivering the needed large quantities of energy safely, economically, reliably and in a sustainable way, both environmentally and as regards the available resource-base. (author)

Why nuclear energy is essential to reduce anthropogenic greenhouse gas emission rates

Energy Technology Data Exchange (ETDEWEB)

Alonso, A. [Univ. Politecnica de Madrid, Madrid (Spain); Brook, B.W. [Univ. of Tasmania, Hobart TAS (Australia); Meneley, D.A. [Candu Energy Inc., Mississauga, Ontario (Canada); Misak, J. [UJV-Rez, Prague (Czech Republic); Blees, T. [Science Council for Global Initiatives, Chicago, Illinois (United States); Van Erp, J.B. [Illinois Commission on Atomic Energy, Chicago, Illinois (United States)

2015-12-15

Reduction of anthropogenic greenhouse gas emissions is advocated by the Intergovernmental Panel on Climate Change. To achieve this target, countries have opted for renewable energy sources, primarily wind and solar. These renewables will be unable to supply the needed large quantities of energy to run industrial societies sustainably, economically and reliably because they are inherently intermittent, depending on flexible backup power or on energy storage for delivery of base-load quantities of electrical energy. The backup power is derived in most cases from combustion of natural gas. Intermittent energy sources, if used in this way, do not meet the requirements of sustainability, nor are they economically viable because they require redundant, under- utilized investment in capacity both for generation and for transmission. Because methane is a potent greenhouse gas, the equivalent carbon dioxide value of methane may cause gas-fired stations to emit more greenhouse gas than coal-fired plants of the same power for currently reported leakage rates of the natural gas. Likewise, intermittent wind/solar photovoltaic systems backed up by gas-fu:ed power plants also release substantial amounts of carbon-dioxide- equivalent greenhouse gas to make such a combination environmentally unacceptable. In the long term, nuclear fission technology is the only known energy source that is capable of delivering the needed large quantities of energy safely, economically, reliably and in a sustainable way, both environmentally and as regards the available resource-base. (author)

Biodiversity and its informative value in evaluation of localities under anthropogenic stress

International Nuclear Information System (INIS)

Dusek, L.; Jarkovsky, J.; Hodovsky, J.; Zahradkova, S.; Brabec, K.; Gelnar, M.; Andel, P.

2003-01-01

Biomonitoring of aquatic and terrestrial ecosystems became a frequent and valuable approach that is widely recognized as a necessary supplement to still more standard chemical monitoring programmes. Biomonitoring implies bioindication of changes that are routinely viewed as negative changes in biological systems due to the influence of stress factors, mostly of anthropogenic origin. Although there are an increasing number of scientific papers devoted to bioindication at the level of individual species or individual specimen (toxicity and genotoxicity testing, biomarkers etc.), complex biomonitoring at the ecosystem level seems to be rather difficult to manage and interpret. Although biodiversity is one of the central themes of ecology and ecotoxicology as well, there is still considerable disagreement in methodology of its comprehensive evaluation. Here we are presenting several approaches to biodiversity evaluation and results interpretation. Conclusions on methodology and interpretation are made on two sets of data - fish parasites under different environmental conditions and a lichen community under emission loading. We can conclude that biodiversity (community composition and structure) analysis could be used for: i) Retrospective bioindication, where it represents indication of complex changes, sensitive early warning, and indication with long-term memory, and/ or ii) prospective assessment, where it represents ecosystem health and stability. Best results are obtained when the biological community is stratified in order to reach environmentally reasonable units; and, these bioindicative components of the community are necessary for effective monitoring plans or ecological risk assessment studies. (authors)

Phytotoxins: environmental micropollutants of concern?

Science.gov (United States)

Bucheli, Thomas D

2014-11-18

Natural toxins such as mycotoxins or phytotoxins (bioactive compounds from fungi and plants, respectively) have been widely studied in food and feed, where they are stated to out-compete synthetic chemicals in their overall human and animal toxicological risk. A similar perception and awareness is yet largely missing for environmental safety. This article attempts to raise concern in this regard, by providing (circumstantial) evidence that phytotoxins in particular can be emitted into the environment, where they may contribute to the complex mixture of organic micropollutants. Exposures can be orders-of-magnitude higher in anthropogenically managed/affected (agro-)ecosystems than in the pristine environment.

USGS Environmental health science strategy: providing environmental health science for a changing world: public review release

Science.gov (United States)

Bright, Patricia R.; Buxton, Herbert T.; Balistrieri, Laurie S.; Barber, Larry B.; Chapelle, Francis H.; Cross, Paul C.; Krabbenhoft, David P.; Plumlee, Geoffrey S.; Sleeman, Jonathan M.; Tillitt, Donald E.; Toccalino, Patricia L.; Winton, James R.

2012-01-01

America has an abundance of natural resources. We have bountiful clean water, fertile soil, and unrivaled national parks, wildlife refuges, and public lands. These resources enrich our lives and preserve our health and wellbeing. These resources have been maintained because of our history of respect for their value and an enduring commitment to their vigilant protection. Awareness of the social, economic, and personal value of the health of our environment is increasing. The emergence of environmentally driven diseases caused by environmental exposure to contaminants and pathogens is a growing concern worldwide. New health threats and patterns of established threats are affected by both natural and anthropogenic changes to the environment. Human activities are key drivers of emerging (new and re-emerging) health threats. Societal demands for land and natural resources, a better quality of life, improved economic prosperity, and the environmental impacts associated with these demands will continue to increase. Natural earth processes, climate trends, and related climatic events will add to the environmental impact of human activities. These environmental drivers will influence exposure to disease agents, including viral, bacterial, prion, and fungal pathogens, parasites, natural earth materials, toxins and other biogenic compounds, and synthetic chemicals and substances. The U.S. Geological Survey (USGS) defines environmental health science broadly as the interdisciplinary study of relations among the quality of the physical environment, the health of the living environment, and human health. The interactions among these three spheres are driven by human activities, ecological processes, and natural earth processes; the interactions affect exposure to contaminants and pathogens and the severity of environmentally driven diseases in animals and people. This definition provides USGS with a framework for synthesizing natural science information from across the Bureau

Natural and Anthropogenic Methane Sources, New England, USA, 1990-1994

Data.gov (United States)

National Aeronautics and Space Administration — This data set contains an inventory of natural and anthropogenic methane emissions for all counties in the six New England states of Connecticut, Rhode Island,...

A tiered observational system for anthropogenic methane emissions

Science.gov (United States)

Duren, R. M.; Miller, C. E.; Hulley, G. C.; Hook, S. J.; Sander, S. P.

2014-12-01

Improved understanding of anthropogenic methane emissions is required for closing the global carbon budget and addressing priority challenges in climate policy. Several decades of top-down and bottom-up studies show that anthropogenic methane emissions are systematically underestimated in key regions and economic sectors. These uncertainties have been compounded by the dramatic rise of disruptive technologies (e.g., the transformation in the US energy system due to unconventional gas and oil production). Methane flux estimates derived from inverse analyses and aircraft-based mass balance approaches underscore the disagreement in nationally and regionally reported methane emissions as well as the possibility of a long-tail distribution in fugitive emissions spanning the US natural gas supply chain; i.e. a small number of super-emitters may be responsible for most of the observed anomalies. Other studies highlight the challenges of sectoral and spatial attribution of fugitive emissions - including the relative contributions of dairies vs oil and gas production or disentangling the contributions of natural gas transmission, distribution, and consumption or landfill emissions in complex urban environments. Limited observational data remains a foundational barrier to resolving these challenges. We present a tiered observing system strategy for persistent, high-frequency monitoring over large areas to provide remote detection, geolocation and quantification of significant anthropogenic methane emissions across cities, states, basins and continents. We describe how this would both improve confidence in methane emission estimates and expedite resolution of fugitive emissions and leaks. We summarize recent prototype field campaigns that employ multiple vantage points and measurement techniques (including NASA's CARVE and HyTES aircraft and PanFTS instrument on Mt Wilson). We share preliminary results of this tiered observational approach including examples of individual

Anthropogenically enhanced chemical weathering and carbon evasion in the Yangtze Basin

Science.gov (United States)

Guo, Jingheng; Wang, Fushun; Vogt, Rolf David; Zhang, Yuhang; Liu, Cong-Qiang

2015-01-01

Chemical weathering is a fundamental geochemical process regulating the atmosphere-land-ocean fluxes and earth’s climate. It is under natural conditions driven primarily by weak carbonic acid that originates from atmosphere CO2 or soil respiration. Chemical weathering is therefore assumed as positively coupled with its CO2 consumption in contemporary geochemistry. Strong acids (i.e. sulfuric- and nitric acid) from anthropogenic sources have been found to influence the weathering rate and CO2 consumption, but their integrated effects remain absent in the world largest river basins. By interpreting the water chemistry and overall proton budget in the Yangtze Basin, we found that anthropogenic acidification had enhanced the chemical weathering by 40% during the past three decades, leading to an increase of 30% in solute discharged to the ocean. Moreover, substitution of carbonic acid by strong acids increased inorganic carbon evasion, offsetting 30% of the CO2 consumption by carbonic weathering. Our assessments show that anthropogenic loadings of sulfuric and nitrogen compounds accelerate chemical weathering but lower its CO2 sequestration. These findings have significant relevance to improving our contemporary global biogeochemical budgets. PMID:26150000

Environmental Impact of Flame Retardants (Persistence and Biodegradability

Directory of Open Access Journals (Sweden)

Asher Brenner

2009-02-01

Full Text Available Flame-retardants (FR are a group of anthropogenic environmental contaminants used at relatively high concentrations in many applications. Currently, the largest market group of FRs is the brominated flame retardants (BFRs. Many of the BFRs are considered toxic, persistent and bioaccumulative. Bioremediation of contaminated water, soil and sediments is a possible solution for the problem. However, the main problem with this approach is the lack of knowledge concerning appropriate microorganisms, biochemical pathways and operational conditions facilitating degradation of these chemicals at an acceptable rate. This paper reviews and discusses current knowledge and recent developments related to the environmental fate and impact of FRs in natural systems and in engineered treatment processes.

Geochemical analysis of sediments from a semi-enclosed bay (Dongshan Bay, southeast China) to determine the anthropogenic impact and source.

Science.gov (United States)

Xu, Yonghang; Sun, Qinqin; Ye, Xiang; Yin, Xijie; Li, Dongyi; Wang, Liang; Wang, Aijun; Li, Yunhai

2017-05-01

The geochemical compositions of sediments in the Dongshan Bay, a semi-enclosed bay on the southeast coast of China, were obtained to identify pollutant sources and evaluate the anthropogenic impacts over the last 100 years. The results indicated that the metal flux had been increasing since the 1980s. Enrichment factor values (Pb, Zn and Cu) suggested only slight enrichment. The proportion of anthropogenic Pb changed from 9% to 15% during 2000-2014. Coal combustion might be an important contamination source in the Dongshan Bay. The historical variation in the metal flux reflected the economic development and urbanization in the Zhangjiang drainage area in the past 30 years. According to the Landsat satellite remote sensing data, the urbanization area expanded approximately three times from 1995 to 2010. The δ 13 C values (-21‰ to -23‰) of the organic matter (OM) in the sediments indicated that the OM was primarily sourced from aquatic, terrigenous and marsh C 3 plants. Nitrogen was mainly derived from aquatic plants and terrigenous erosion before the 1980s. However, the total organic carbon (TOC) contents, total nitrogen (TN) contents and δ 15 N had been increasing since the 1980s, which suggested that the sources of nitrogen were soil erosion, fertilizer and sewage. In addition, the TOC and TN fluxes in the Dongshan Bay had significantly increased since the 1980s, which reflected the use of N fertilizer. However, the TOC and TN fluxes significantly decreased in the past decade because environmental awareness increased and environmental protection policies were implemented. Copyright © 2017 Elsevier Ltd. All rights reserved.

Avoiding Dangerous Anthropogenic Interference with the Climate System

Energy Technology Data Exchange (ETDEWEB)

Keller, K. [Department of Geosciences, Penn State, PA (United States); Hall, M. [Brookings Institution, Washington, DC (United States); Kim, Seung-Rae [Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton, NJ (United States); Bradford, D.F. [Department of Economics, Princeton University, Princeton, NJ (United States); Oppenheimer, M. [Woodrow Wilson School and Department of Geosciences, Princeton University, Robertson Hall 448, Princeton, NJ, 08544 (United States)

2005-12-01

The UN Framework Convention on Climate Change calls for the avoidance of 'dangerous anthropogenic interference with the climate system'. Among the many plausible choices, dangerous interference with the climate system may be interpreted as anthropogenic radiative forcing causing distinct and widespread climate change impacts such as a widespread demise of coral reefs or a disintegration of the West Antarctic ice sheet. The geological record and numerical models suggest that limiting global warming below critical temperature thresholds significantly reduces the likelihood of these eventualities. Here we analyze economically optimal policies that may ensure this risk-reduction. Reducing the risk of a widespread coral reef demise implies drastic reductions in greenhouse gas emissions within decades. Virtually unchecked greenhouse gas emissions to date (combined with the inertia of the coupled natural and human systems) may have already committed future societies to a widespread demise of coral reefs. Policies to reduce the risk of a West Antarctic ice sheet disintegration allow for a smoother decarbonization of the economy within a century and may well increase consumption in the long run.

Intercalibration of selected anthropogenic radionuclides for the GEOTRACES Program

DEFF Research Database (Denmark)

Kenna, Timothy C.; Masqué, Pere; Mas, Jose Luis

2012-01-01

As part of the GEOTRACES Program, six laboratories participated in an intercalibration exercise on several anthropogenic radionuclides of interest. The effort was successful for 239,240Pu activity, 240Pu/239Pu isotope ratio, and 137Cs activity measured in filtered seawater samples from the Bermuda...... Atlantic Time Series station (BATS) and a site on the continental slope of the Northeastern U.S. A limited number of analyses were reported for 237Np, 241Am, 90Sr, and 238Pu in filtered seawater. Intercalibration of any of the isotopes of interest in filtered particulate matter was unsuccessful due...... to insufficient size of the samples distributed. Methods used were based on traditional radio-counting techniques and inductively coupled plasma mass spectrometry (ICP-MS). Although the majority of analyses were performed on samples ≥ 60 L, one lab demonstrated the ability to analyze several of the anthropogenic...

Human Rights and the Environmental Protection: The Naïveté in Environmental Culture

Directory of Open Access Journals (Sweden)

Made Adhitya Anggriawan Wisadha

2018-05-01

Full Text Available There are growing trends in the human rights to substantially extend the values to protect the environment or moreover to welcome the ideas of the rights to environment, not to mention the rights of environment. The purpose is to inclusively embrace the environmental problems wherein the humanity challenges posited on, but this agenda may leave a room of doubt how far the human rights body can address the environmental destruction as it needs the interplay of culture and environmental ethics to promoting such concepts. Therefore, this paper aims to identify the justification of how human rights in the environmental protection in the contemporary discourse are bringing to light, as many current cases attempt to linkage the environmental approach to the human rights instrument, such as the rights to life, healthy environment, and intergenerational equity. To analyse further, the theoretical framework in this paper will be explicated by environmental culture paradigm which illustrates the egalitarian concept between human and environment to elicit the clear thoughts of how human rights is naïve to protect the environment. This article will firstly depict the human rights and the environmental protection discourse and then, explore the naïveté narratives of environmental culture about the ecological crisis roots that are fundamentally anthropogenic, as to reflect the ground realities how this nexus will play out. Finally, this paper found the moral justification per se relies on the effort of elaborating the human prudence in their relationship with nature, albeit bringing the naïveté.

Edge responses are different in edges under natural versus anthropogenic influence: a meta-analysis using ground beetles.

Science.gov (United States)

Magura, Tibor; Lövei, Gábor L; Tóthmérész, Béla

2017-02-01

Most edges are anthropogenic in origin, but are distinguishable by their maintaining processes (natural vs. continued anthropogenic interventions: forestry, agriculture, urbanization). We hypothesized that the dissimilar edge histories will be reflected in the diversity and assemblage composition of inhabitants. Testing this "history-based edge effect" hypothesis, we evaluated published information on a common insect group, ground beetles (Coleoptera: Carabidae) in forest edges. A meta-analysis showed that the diversity-enhancing properties of edges significantly differed according to their history. Forest edges maintained by natural processes had significantly higher species richness than their interiors, while edges with continued anthropogenic influence did not. The filter function of edges was also essentially different depending on their history. For forest specialist species, edges maintained by natural processes were penetrable, allowing these species to move right through the edges, while edges still under anthropogenic interventions were impenetrable, preventing the dispersal of forest specialists out of the forest. For species inhabiting the surrounding matrix (open-habitat and generalist species), edges created by forestry activities were penetrable, and such species also invaded the forest interior. However, natural forest edges constituted a barrier and prevented the invasion of matrix species into the forest interior. Preserving and protecting all edges maintained by natural processes, and preventing anthropogenic changes to their structure, composition, and characteristics are key factors to sustain biodiversity in forests. Moreover, the increasing presence of anthropogenic edges in a landscape is to be avoided, as they contribute to the loss of biodiversity. Simultaneously, edges under continued anthropogenic disturbance should be restored by increasing habitat heterogeneity.

Anthropogenic Sulfur Dioxide Emissions, 1850-2005: National and Regional Data Set by Source Category, Version 2.86

Data.gov (United States)

National Aeronautics and Space Administration — The Anthropogenic Sulfur Dioxide Emissions, 1850-2005: National and Regional Data Set by Source Category, Version 2.86 provides annual estimates of anthropogenic...

Global alteration of climate - hopes and fears

International Nuclear Information System (INIS)

Viktorov, V.V.

1992-01-01

Problems concerning gaseous emission affecting the global climate alteration connected with hotbed effect are considered. Economical and social-political ways of solution of the problem of minimization of gaseous wastes are described. Role of nuclear power plants and alternative power plants in the hotbed effect are analyzed. International cooperation in environmental protection policy is discussed

Environmental benefits and drawbacks of composite fuels based on industrial wastes and different ranks of coal.

Science.gov (United States)

Nyashina, G S; Vershinina, K Yu; Dmitrienko, M A; Strizhak, P A

2018-04-05

A promising solution to many problems that thermal power industry is facing today would be switching from conventional coal dust combustion to coal-water slurries containing petrochemicals (CWSP). Here, we perform an experimental study of the most hazardous anthropogenic emissions (sulfur and nitrogen oxides) from the combustion of high-potential CWSP. We identify the main benefits and potential drawbacks of using CWSP in thermal power industry. A set of components and additives to CWSP are explored that significantly affect the environmental and energy performance of fuels. The anthropogenic emissions from the combustion of CWSP made of widespread coal and oil processing wastes are no higher than those from coal dust combustion. Using specialized additives to CWSP, we can change the concentrations of NO x and SO x several times. The most appealing additives to CWSP are sawdust, straw, charcoal, limestone, and glycerol. They provide better environmental, economic, and energy performance and improve the rheological properties of CWSP. Waste oils and oil sludge added to CWSP may impair the environmental performance but boost the cost and energy efficiency. Using coal-water slurries containing petrochemicals as a fuel at thermal power plants is an environmentally friendly as well as cost- and energy-efficient way to recover industrial wastes. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of carbonate chemistry alteration on the early embryonic development of the Pacific oyster (Crassostrea gigas)

OpenAIRE

Gazeau Frédéric; Gattuso Jean-Pierre; Greaves Mervyn; Elderfield Henry; Peene J; Heip Carlo H R; Middelburg Jack J

2011-01-01

Ocean acidification, due to anthropogenic CO(2) absorption by the ocean, may have profound impacts on marine biota. Calcareous organisms are expected to be particularly sensitive due to the decreasing availability of carbonate ions driven by decreasing pH levels. Recently, some studies focused on the early life stages of mollusks that are supposedly more sensitive to environmental disturbances than adult stages. Although these studies have shown decreased growth rates and increased proportion...

The human footprint in the west: a large-scale analysis of anthropogenic impacts.

Science.gov (United States)

Leu, M.; Hanser, S.E.; Knick, S.T.

2008-01-01

Anthropogenic features such as urbanization, roads, and power lines, are increasing in western United States landscapes in response to rapidly growing human populations. However, their spatial effects have not been evaluated. Our goal was to model the human footprint across the western United States. We first delineated the actual area occupied by anthropogenic features, the physical effect area. Next, we developed the human footprint model based on the ecological effect area, the zone influenced by features beyond their physical presence, by combining seven input models: three models quantified top-down anthropogenic influences of synanthropic predators (avian predators, domestic dog and cat presence risk), and four models quantified bottom-up anthropogenic influences on habitat (invasion of exotic plants, human-caused fires, energy extraction, and anthropogenic wildland fragmentation). Using independent bird population data, we found bird abundance of four synanthropic species to correlate positively with human footprint intensity and negatively for three of the six species influenced by habitat fragmentation. We then evaluated the extent of the human footprint in relation to terrestrial (ecoregions) and aquatic systems (major rivers and lakes), regional management and conservation status, physical environment, and temporal changes in human actions. The physical effect area of anthropogenic features covered 13% of the western United States with agricultural land (9.8%) being most dominant. High-intensity human footprint areas (class 8–10) overlapped highly productive low-elevation private landholdings and covered 7% of the western United States compared to 48% for low-intensity areas (class 1–3), which were confined to low-productivity high-elevation federal landholdings. Areas within 1 km of rivers were more affected by the human footprint compared to lakes. Percentage human population growth was higher in low-intensity human footprint areas. The

Modeled impact of anthropogenic land cover change on climate

Science.gov (United States)

Findell, K.L.; Shevliakova, E.; Milly, P.C.D.; Stouffer, R.J.

2007-01-01

Equilibrium experiments with the Geophysical Fluid Dynamics Laboratory's climate model are used to investigate the impact of anthropogenic land cover change on climate. Regions of altered land cover include large portions of Europe, India, eastern China, and the eastern United States. Smaller areas of change are present in various tropical regions. This study focuses on the impacts of biophysical changes associated with the land cover change (albedo, root and stomatal properties, roughness length), which is almost exclusively a conversion from forest to grassland in the model; the effects of irrigation or other water management practices and the effects of atmospheric carbon dioxide changes associated with land cover conversion are not included in these experiments. The model suggests that observed land cover changes have little or no impact on globally averaged climatic variables (e.g., 2-m air temperature is 0.008 K warmer in a simulation with 1990 land cover compared to a simulation with potential natural vegetation cover). Differences in the annual mean climatic fields analyzed did not exhibit global field significance. Within some of the regions of land cover change, however, there are relatively large changes of many surface climatic variables. These changes are highly significant locally in the annual mean and in most months of the year in eastern Europe and northern India. They can be explained mainly as direct and indirect consequences of model-prescribed increases in surface albedo, decreases in rooting depth, and changes of stomatal control that accompany deforestation. ?? 2007 American Meteorological Society.

Diversity of medicinal plants and anthropogenic threats in the ...

African Journals Online (AJOL)

Diversity of medicinal plants and anthropogenic threats in the Samburu Central Sub-County of Kenya. ... Biodiversity of medicinal plants and effects of human activities on availability of traditional ... There is, therefore need to adopt management strategies that enhance the conservation of these valuable natural resources.

Quantitative identification and source apportionment of anthropogenic heavy metals in marine sediment of Hong Kong

Science.gov (United States)

Zhou, Feng; Guo, Huaicheng; Liu, Lei

2007-10-01

Based on ten heavy metals collected twice annually at 59 sites from 1998 to 2004, enrichment factors (EFs), principal component analysis (PCA) and multivariate linear regression of absolute principal component scores (MLR-APCS) were used in identification and source apportionment of the anthropogenic heavy metals in marine sediment. EFs with Fe as a normalizer and local background as reference values was properly tested and suitable in Hong Kong, and Zn, Ni, Pb, Cu, Cd, Hg and Cr mainly originated from anthropogenic sources, while Al, Mn and Fe were derived from rocks weathering. Rotated PCA and GIS mapping further identified two types of anthropogenic sources and their impacted regions: (1) electronic industrial pollution, riparian runoff and vehicle exhaust impacted the entire Victoria Harbour, inner Tolo Harbour, Eastern Buffer, inner Deep Bay and Cheung Chau; and (2) discharges from textile factories and paint, influenced Tsuen Wan Bay and Kwun Tong typhoon shelter and Rambler Channel. In addition, MLR-APCS was successfully introduced to quantitatively determine the source contributions with uncertainties almost less than 8%: the first anthropogenic sources were responsible for 50.0, 45.1, 86.6, 78.9 and 87.5% of the Zn, Pb, Cu, Cd and Hg, respectively, whereas 49.9% of the Ni and 58.4% of the Cr came from the second anthropogenic sources.

A review of marine anthropogenic CO2 definitions: introducing a thermodynamic approach based on observations

International Nuclear Information System (INIS)

Friis, Karsten

2006-01-01

A review of existing methods that define anthropogenic CO 2 as deduced from total inorganic carbon is presented. A refined approach to define anthropogenic CO 2 is introduced that has a stronger thermodynamic orientation than current methods, and is based on a back-calculation technique by Chen and Millero and Poisson and Chen. Anthropogenic CO 2 results of the new technique are compared with results from the original technique as well as with results of the technique of Gruber et al. The new technique is furthermore applied to three time-separated data sets in the subpolar North Atlantic and shows consistent results with regard to available data quality and anthropogenic CO 2 quantities. The difference between the new thermodynamic approach and the anthropogenic CO 2 definition of Gruber et al., which is termed mechanistic, is discussed. Here likely changes in the CO 2 solubility pump are a thermodynamic property of this definition, whereas it is a separate phenomenon in the mechanistic definition. The thermodynamic approach is not without caveats, but points to improvements by the synergistic use of model results and those from observations. Future improvements are considered for the initial saturation state of oxygen and CO 2 , at the instant the surface water loses contact with the atmosphere and for variations in the Redfield ratio

THE CONCENTRATION OF PHOTOSINTHESIS PIGMENTS IN THE ANTHROPOGENIC PLANT COMMUNITIES IN TOBOLSK TOWN

OpenAIRE

Еlena Ivanovna Popova

2016-01-01

Photosynthesis means a lot in the life of a plant body. For the normal photosynthesis process it is necessary to have certain external and internal conditions. The topic of the research is the study of photosynthesis pigments in anthropogenic plant communities. The aim of our work was to study the pigment composition plants of anthropogenic phytocenoses. Methods: we have used the spectrophotometric method to define the concentration of pigments. Results: the research has shown that the concen...

Anthropogenic sea level rise and adaptation in the Yangtze estuary

Science.gov (United States)

Cheng, H.; Chen, J.; Chen, Z.; Ruan, R.; Xu, G.; Zeng, G.; Zhu, J.; Dai, Z.; Gu, S.; Zhang, X.; Wang, H.

2016-02-01

Sea level rise is a major projected threat of climate change. There are regional variations in sea level changes, depending on both naturally the tectonic subsidence, geomorphology, naturally changing river inputs and anthropogenic driven forces as artificial reservoir water impoundment within the watershed and urban land subsidence driven by ground water depletion in the river delta. Little is known on regional sea level fall in response to the channel erosion due to the sediment discharge decline by reservoir interception in the upstream watershed, and water level rise driven by anthropogenic measures as the land reclamation, deep waterway regulation and fresh water reservoir construction to the sea level change in estuaries. Changing coastal cities are situated in the delta regions expected to be threatened in various degrees. Shanghai belongs to those cities. Here we show that the anthropogenic driven sea level rise in the Yangtze estuary from the point of view of the continuous hydrodynamic system consisted of river catchment, estuary and coastal sea. Land subsidence is cited as 4 mm/a (2011-2030). Scour depth of the estuarine channel by upstream engineering as Three Gauge Dam is estimated at 2-10 cm (2011-2030). The rise of water level by deep waterway and land reclamation is estimated at 8-10 cm (2011-2030). The relative sea level rise will be speculated about 10 -16 cm (2011-2030), which these anthropogenic sea level changes will be imposed into the absolute sea level rise 2 mm/a and tectonic subsidence 1 mm/a measured in 1990s. The action guideline to the sea level rise strategy in the Shanghai city have been proposed to the Shanghai government as (1) recent actions (2012-2015) to upgrade the city water supply and drainage engineering and protective engineering; (2) interim actions (2016-2020) to improve sea level monitoring and early warning system, and then the special, city, regional planning considering sea level rise; (3) long term actions (2021

Stable nitrogen isotopes in coastal macroalgae: Geographic and anthropogenic variability

Energy Technology Data Exchange (ETDEWEB)

Viana, Inés G., E-mail: ines.gonzalez@co.ieo.es; Bode, Antonio

2013-01-15

Growing human population adds to the natural nitrogen loads to coastal waters. Both anthropogenic and natural nitrogen is readily incorporated in new biomass, and these different nitrogen sources may be traced by the measurement of the ratio of stable nitrogen isotopes (δ{sup 15}N). In this study δ{sup 15}N was determined in two species of macroalgae (Ascophyllum nodosum and Fucus vesiculosus), and in nitrate and ammonium to determine the relative importance of anthropogenic versus natural sources of nitrogen along the coast of NW Spain. Both algal species and nitrogen sources showed similar isotopic enrichment for a given site, but algal δ{sup 15}N was not related to either inorganic nitrogen concentrations or δ{sup 15}N in the water samples. The latter suggests that inorganic nitrogen inputs are variable and do not always leave an isotopic trace in macroalgae. However, a significant linear decrease in macroalgal δ{sup 15}N along the coast is consistent with the differential effect of upwelling. Besides this geographic variability, the influence of anthropogenic nitrogen sources is evidenced by higher δ{sup 15}N in macroalgae from rias and estuaries compared to those from open coastal areas and in areas with more than 15 × 10{sup 3} inhabitants in the watershed. These results indicate that, in contrast with other studies, macroalgal δ{sup 15}N is not simply related to either inorganic nitrogen concentrations or human population size but depends on other factors as the upwelling or the efficiency of local waste treatment systems. - Highlights: ► Anthropogenic versus upwelling nitrogen effect on macroalgal δ{sup 15}N was studied. ► The influence of populations and upwelling has not been made before on macroalgal δ{sup 15}N. ► Natural variability has not been taken into account in most biomonitoring studies. ► Upwelling explains most of the variability in δ{sup 15}N in macroalgae.

Detecting anthropogenic footprints in sea level rise: the role of complex colored noise

Science.gov (United States)

Dangendorf, Sönke; Marcos, Marta; Müller, Alfred; Zorita, Eduardo; Jensen, Jürgen

2015-04-01

While there is scientific consensus that global mean sea level (MSL) is rising since the late 19th century, it remains unclear how much of this rise is due to natural variability or anthropogenic forcing. Uncovering the anthropogenic contribution requires profound knowledge about the persistence of natural MSL variations. This is challenging, since observational time series represent the superposition of various processes with different spectral properties. Here we statistically estimate the upper bounds of naturally forced centennial MSL trends on the basis of two separate components: a slowly varying volumetric (mass and density changes) and a more rapidly changing atmospheric component. Resting on a combination of spectral analyses of tide gauge records, ocean reanalysis data and numerical Monte-Carlo experiments, we find that in records where transient atmospheric processes dominate, the persistence of natural volumetric changes is underestimated. If each component is assessed separately, natural centennial trends are locally up to ~0.5 mm/yr larger than in case of an integrated assessment. This implies that external trends in MSL rise related to anthropogenic forcing might be generally overestimated. By applying our approach to the outputs of a centennial ocean reanalysis (SODA), we estimate maximum natural trends in the order of 1 mm/yr for the global average. This value is larger than previous estimates, but consistent with recent paleo evidence from periods in which the anthropogenic contribution was absent. Comparing our estimate to the observed 20th century MSL rise of 1.7 mm/yr suggests a minimum external contribution of at least 0.7 mm/yr. We conclude that an accurate detection of anthropogenic footprints in MSL rise requires a more careful assessment of the persistence of intrinsic natural variability.

Anthropogenic changes and environmental degradation in pre-Hispanic and post-Colonial periods: soil erosion modelled with WEPP during Late Holocene in Teotihuacán Valley (central Mexico)

Science.gov (United States)

Lourdes González-Arqueros, M.; Mendoza Cantú, Manuel E.

2015-04-01

Land use changes and support practices are a worldwide significant issue in soil erosion and subsequently, land degradation. Anthropogenic changes, along different periods of the history in the last 2000 years in the Valley of Teotihuacan (central Mexico), highlight that soil erosion varies depending on how the management and the intensity of soil use is handled, considering the soils as a main resource. As a part of a broader effort to reconstruct the erosion dynamics in the Teotihuacán Valley through geoarchaeological approaches, this study apply a process-based watershed hydrology and upland erosion model, Water Erosion Prediction Project (WEPP). This research aims to contribute with insights through modelling and to recreate soil erosion and sedimentation dynamics in several historical periods with different environmental and anthropogenic scenarios. The Geo-spatial interface for WEPP (GeoWEPP) was used to characterize location of detachment, depositions and erosion predicted on the profile through time, based on current and hypothetical reconstructed conditions in the watershed. Climate, topography, soil and land use were used as inputs for the WEPP model to estimate runoff fluxes, soil loss rates, and sediment delivery ratio (SDR) for three historical scenarios: current period, reconstructed Teotihuacán period (AD 1-650), and reconstructed Aztec period (AD 1325-1520). Over a simulated and stablished timeframe for those social periods, the runoff, soil loss rate and SDR were estimated to be greater during the Aztec period. We assume that in general the climate conditions for this period were wetter, compared with present, in agreement with several authors that proposed climate reconstructions for the center of Mexico. It is also highlighted that support practices were more effective in this period. The next period with higher values is the current one, and fewer rates are estimated for the Teotihuacán period. This comparison release new arguments in the

U.S. Geological Survey environmental health science strategy: Providing environmental health science for a changing world

Science.gov (United States)

Bright, Patricia R.; Buxton, Herbert T.; Balistrieri, Laurie S.; Barber, Larry B.; Chapelle, Francis H.; Cross, Paul C.; Krabbenhoft, David P.; Plumlee, Geoffrey S.; Sleeman, Jonathan M.; Tillitt, Donald E.; Toccalino, Patricia L.; Winton, James R.

2013-01-01

America has an abundance of natural resources. We have bountiful clean water, fertile soil, and unrivaled national parks, wildlife refuges, and public lands. These resources enrich our lives and preserve our health and wellbeing. These resources have been maintained because of our history of respect for their value and an enduring commitment to their vigilant protection. Awareness of the social, economic, and personal value of the health of our environment is increasing. The emergence of environmentally driven diseases caused by exposure to contaminants and pathogens is a growing concern worldwide. New health threats and patterns of established threats are affected by both natural and anthropogenic changes to the environment. Human activities are key drivers of emerging (new and re-emerging) health threats. Societal demands for land and natural resources, quality of life, and economic prosperity lead to environmental change. Natural earth processes, climate trends, and related climatic events will compound the environmental impact of human activities. These environmental drivers will influence exposure to disease agents, including viral, bacterial, prion, and fungal pathogens, parasites, synthetic chemicals and substances, natural earth materials, toxins, and other biogenic compounds.

Global issues in environmental medicine.

Science.gov (United States)

Goldstein, B D

1993-03-01

This overview will discuss a number of the issues posed by the challenge of international environmental health. The reasons that environmental problems occurring elsewhere in the world are of importance to occupational and environmental physicians in North America include the interconnectedness of the biosphere of our planet so that environmental alterations in one part of the globe can have an adverse outcome on our health and well-being; the often high levels of pollution and environmental degradation elsewhere provide an opportunity to determine and predict adverse consequences of environmental agents pertinent to protecting our own health; and, most importantly, our own ability to provide assistance in helping economic development occur in a setting of low risk of environmental pollution.

Biodegradation of aged diesel in diverse soil matrixes: impact of environmental conditions and bioavailability on microbial remediation capacity

NARCIS (Netherlands)

Sutton, N.B.; Gaans, van P.; Langenhoff, A.A.M.; Maphosa, F.; Smidt, H.; Grotenhuis, J.T.C.; Rijnaarts, H.H.M.

2013-01-01

While bioremediation of total petroleum hydrocarbons (TPH) is in general a robust technique, heterogeneity in terms of contaminant and environmental characteristics can impact the extent of biodegradation. The current study investigates the implications of different soil matrix types (anthropogenic

Hunting, Exotic Carnivores, and Habitat Loss: Anthropogenic Effects on a Native Carnivore Community, Madagascar

OpenAIRE

Farris, Zach J.; Golden, Christopher D.; Karpanty, Sarah; Murphy, Asia; Stauffer, Dean; Ratelolahy, Felix; Andrianjakarivelo, Vonjy; Holmes, Christopher M.; Kelly, Marcella J.

2015-01-01

The wide-ranging, cumulative, negative effects of anthropogenic disturbance, including habitat degradation, exotic species, and hunting, on native wildlife has been well documented across a range of habitats worldwide with carnivores potentially being the most vulnerable due to their more extinction prone characteristics. Investigating the effects of anthropogenic pressures on sympatric carnivores is needed to improve our ability to develop targeted, effective management plans for carnivore c...

Low concentrations, potential ecological consequences: Synthetic estrogens alter life-history and demographic structures of aquatic invertebrates

International Nuclear Information System (INIS)

Souza, María Sol; Hallgren, Per; Balseiro, Esteban; Hansson, Lars-Anders

2013-01-01

Contraceptive drugs are nowadays found in aquatic environments around the globe. Particularly, 17α-ethinylestradiol (EE 2 ) may act even at low concentrations, such as those recorded in natural ecosystems. We evaluated the physiological effects of EE 2 on cyclopoids and calanoids, common copepods in both marine and freshwater communities. We used three EE 2 concentrations and assessed its impact on activity of different physiological endpoints: Acetylcholinesterase (neurotransmission), Glutathione S-transferase (detoxifying system), and Caspase-3 (apoptosis). While EE 2 exerts, distinctive effect on detoxifying and apoptotic systems, no effect on AChE was observed at environmental doses. Our results show that EE 2 exposure affects differently copepod physiology endpoints, altering moulting process, adult recruitment in calanoids and calanoid to cyclopoid ratio. The ecological consequences of this underlying physiological process may affect since life history to population and community structures, and this represent a new aspects of this xenobiotic in natural systems. Highlights: •We evaluated physiological effects of 17α-ethinylestradiol (EE 2 ) on copepods. •We measured the EE 2 effect on neurotransmission, detoxifying system and apoptosis. •EE 2 exert distinctive effect on detoxifying and apoptotic systems. •EE 2 affects differently calanoids and cyclopoids moulting and adult recruitment. •Physiological impact in invertebrates' communities is a novel aspect of EE 2 effects. -- Anthropogenic estrogens modify the physiological functioning of aquatic invertebrates

Response of air stagnation frequency to anthropogenically enhanced radiative forcing

International Nuclear Information System (INIS)

Horton, Daniel E; Diffenbaugh, Noah S; Harshvardhan

2012-01-01

Stagnant atmospheric conditions can lead to hazardous air quality by allowing ozone and particulate matter to accumulate and persist in the near-surface environment. By changing atmospheric circulation and precipitation patterns, global warming could alter the meteorological factors that regulate air stagnation frequency. We analyze the response of the National Climatic Data Center (NCDC) air stagnation index (ASI) to anthropogenically enhanced radiative forcing using global climate model projections of late-21st century climate change (SRESA1B scenario). Our results indicate that the atmospheric conditions over the highly populated, highly industrialized regions of the eastern United States, Mediterranean Europe, and eastern China are particularly sensitive to global warming, with the occurrence of stagnant conditions projected to increase by 12–25% relative to late-20th century stagnation frequencies (3–18 + days yr −1 ). Changes in the position/strength of the polar jet, in the occurrence of light surface winds, and in the number of precipitation-free days all contribute to more frequent late-21st century air mass stagnation over these high-population regions. In addition, we find substantial inter-model spread in the simulated response of stagnation conditions over some regions using either native or bias corrected global climate model simulations, suggesting that changes in the atmospheric circulation and/or the distribution of precipitation represent important sources of uncertainty in the response of air quality to global warming. (letter)

AMPHIBIAN COMMUNITIES IN BIOGEOCOENOSIS WITH DIFFERENT STAGES OF ANTHROPOGENIC CLYMAX

Directory of Open Access Journals (Sweden)

Marchenkovskaya А. А.

2013-04-01

Full Text Available We examined the abundance of juvenile (fingerlings and yearlings and sexually mature (3-6 years of various anurans at various biotopes with different degrees of anthropogenic influence. Population analysis has revealed that the number of juveniles in all the habitats are depended on type and level of anthropogenic influence. In all the habitats the most numerous species was synanthropic bufo viridis. In biotopes with high contamination of pollutants, only one species of amphibians - the marsh frog has populations with juveniles migrating here in the early fall. The highest number of mature individuals registered for the population of Bombina bombina, pelobates fuscus and in one biotope for hyla arborea. The populations of pelophylax ridibundus could be considered as the most balanced by number of juvenile and mature individuals.

Isotopic signatures of eelgrass (Zostera marina L.) as bioindicator of anthropogenic nutrient input in the western Baltic Sea

International Nuclear Information System (INIS)

Schubert, Philipp R.; Karez, Rolf; Reusch, Thorsten B.H.; Dierking, Jan

2013-01-01

Highlights: • Anthropogenic nitrogen (N) inputs are a global problem, but difficult to quantify. • We tested the use of eelgrass δ 15 N as proxy of such inputs in the Baltic Sea. • The method revealed distinct spatial patterns in sewage N across a eutrophic bay. • Traditional eutrophication measures corroborated the results from δ 15 N values. • Eelgrass δ 15 N ratios have high potential as proxy of sewage-derived N in the Baltic. -- Abstract: Eutrophication is a global environmental problem. Better management of this threat requires more accurate assessments of anthropogenic nitrogen (N) inputs to coastal systems than can be obtained with traditional measures. Recently, primary producer N isotopic signatures have emerged as useful proxy of such inputs. Here, we demonstrated for the first time the applicability of this method using the widespread eelgrass (Zostera marina) in the highly eutrophic Baltic Sea. Spatial availability of sewage N across a bay with one major sewage outflow predicted by eelgrass δ 15 N was high near and downstream of the outflow compared to upstream, but returned to upstream levels within 4 km downstream from the outfall. General conclusions were corroborated by traditional eutrophication measures, but in contrast to these measures were fully quantitative. Eelgrass N isotope ratios therefore show high potential for coastal screens of eutrophication in the Baltic Sea, and in other areas with eelgrass meadows

Evaluation of anthropogenic influences on the Luhuitou fringing reef via spatial and temporal analyses (from isotopic values)

Science.gov (United States)

Cao, D.; Cao, W.; Yu, K.; Wu, G.; Yang, J.; Su, X.; Wang, F.

2017-05-01

Coral reefs have suffered remarkable declines worldwide. Nutrient overenrichment is considered to be one of the primary local causes. The Luhuitou fringing reef in southern China is a well-known tourist destination that is subject to enormous coastal renovation. The mean δ13C, δ15N value, and carbon over nitrogen ratio (C/N) of particulate organic matter were -21.56 ± 1.94‰, 7.04 ± 3.81‰, and 5.81 ± 1.86, respectively, suggesting mixed sources of carbon and nitrogen. The IsoError calculations suggested that marine phytoplankton and marine benthic algae dominated the majority of carbon sources, while anthropogenic and terrestrial organic nitrogen dominated the nitrogen sources. A tendency toward greater terrestrial detritus and anthropogenic-derived discharges was found during dry seasons and greater marine-derived organic matter during wet seasons. These results demonstrated the existence of anthropogenic influences and high dissolved inorganic nitrogen concentrations and C/N ratios. Anthropogenic nutrient discharge moderated nitrogen limitation, whereas phosphorus became more important to the reef ecosystem. Despite the marine carbon sources dominated, freshwater and terrestrial-derived organic carbon sources were also very important. Meanwhile, anthropogenic and terrestrial organic nitrogen sources were dominant. Therefore, pollution from more extensive region and anthropogenic activities from riverine sewage discharges adjacent to reefs should be focused to effectively reduce human-derived nutrients on reefs.

Application Framework Of Integrated Energy Resources Planning Considering Full Environmental Accounting

Energy Technology Data Exchange (ETDEWEB)

Kanayama, Paulo Helio; Morales Udaeta, Miguel Edgar; Ribeiro Galvao, Luis Claudio; Baesso Grimoni, Jose Aquiles

2010-09-15

This paper describes the full environmental accounting being used in RAA (Administrative Region of Aracatuba), an area composed of 43 municipalities in Sao Paulo, Brazil. The full environment accounting shows the vulnerabilities and advantages in the region that can be used as a tool for public awareness and involvement in decision making to choose the most appropriate energy resources of the region. It is characterized by four main environmental categories: aerial, aquatic, land and anthropogenic mediums, each to be used as a tool for decision making in energy planning, specifically with the methodology of PIR - Integrated Energy Resources Planning.

EVALUATION OF SIGNIFICANT ANTHROPOGENIC SOURCES OF RADIATIVELY IMPORTANT TRACE GASES

Science.gov (United States)

The report is an initial evaluation of significant anthropogenic sources of radiatively important trace gases. missions of greenhouse gases from human activities--including fossil fuel combustion, industrial/agricultural activities, and transportation--contribute to the increasin...

Anthropogenic nutrient sources rival natural sources on small scales in the coastal waters of the Southern California Bight

KAUST Repository

Howard, Meredith D. A.; Sutula, Martha; Caron, David A.; Chao, Yi; Farrara, John D.; Frenzel, Hartmut; Jones, Burton; Robertson, George; McLaughlin, Karen; Sengupta, Ashmita

2014-01-01

Anthropogenic nutrients have been shown to provide significant sources of nitrogen (N) that have been linked to increased primary production and harmful algal blooms worldwide. There is a general perception that in upwelling regions, the flux of anthropogenic nutrient inputs is small relative to upwelling flux, and therefore anthropogenic inputs have relatively little effect on the productivity of coastal waters. To test the hypothesis that natural sources (e.g., upwelling) greatly exceed anthropogenic nutrient sources to the Southern California Bight (SCB), this study compared the source contributions of N from four major nutrient sources: (1) upwelling, (2) treated wastewater effluent discharged to ocean outfalls, (3) riverine runoff, and (4) atmospheric deposition. This comparison was made using large regional data sets combined with modeling on both regional and local scales. At the regional bight-wide spatial scale, upwelling was the largest source of N by an order of magnitude to effluent and two orders of magnitude to riverine runoff. However, at smaller spatial scales, more relevant to algal bloom development, natural and anthropogenic contributions were equivalent. In particular, wastewater effluent and upwelling contributed the same quantity of N in several subregions of the SCB. These findings contradict the currently held perception that in upwelling-dominated regions anthropogenic nutrient inputs are negligible, and suggest that anthropogenic nutrients, mainly wastewater effluent, can provide a significant source of nitrogen for nearshore productivity in Southern California coastal waters.

Anthropogenic nutrient sources rival natural sources on small scales in the coastal waters of the Southern California Bight

KAUST Repository

Howard, Meredith D. A.

2014-01-26

Anthropogenic nutrients have been shown to provide significant sources of nitrogen (N) that have been linked to increased primary production and harmful algal blooms worldwide. There is a general perception that in upwelling regions, the flux of anthropogenic nutrient inputs is small relative to upwelling flux, and therefore anthropogenic inputs have relatively little effect on the productivity of coastal waters. To test the hypothesis that natural sources (e.g., upwelling) greatly exceed anthropogenic nutrient sources to the Southern California Bight (SCB), this study compared the source contributions of N from four major nutrient sources: (1) upwelling, (2) treated wastewater effluent discharged to ocean outfalls, (3) riverine runoff, and (4) atmospheric deposition. This comparison was made using large regional data sets combined with modeling on both regional and local scales. At the regional bight-wide spatial scale, upwelling was the largest source of N by an order of magnitude to effluent and two orders of magnitude to riverine runoff. However, at smaller spatial scales, more relevant to algal bloom development, natural and anthropogenic contributions were equivalent. In particular, wastewater effluent and upwelling contributed the same quantity of N in several subregions of the SCB. These findings contradict the currently held perception that in upwelling-dominated regions anthropogenic nutrient inputs are negligible, and suggest that anthropogenic nutrients, mainly wastewater effluent, can provide a significant source of nitrogen for nearshore productivity in Southern California coastal waters.

Anthropogenic impact on diffuse trace metal accumulation in river sediments from agricultural reclamation areas with geochemical and isotopic approaches

Energy Technology Data Exchange (ETDEWEB)

Jiao, Wei; Ouyang, Wei, E-mail: wei@itc.nl; Hao, Fanghua; Lin, Chunye

2015-12-01

A better understanding of anthropogenic impact can help assess the diffuse trace metal accumulation in the agricultural environment. In this study, both river sediments and background soils were collected from a case study area in Northeast China and analyzed for total concentrations of six trace metals, four major elements and three lead isotopes. Results showed that Pb, Cd, Cu, Zn, Cr and Ni have accumulated in the river sediments after about 40 years of agricultural development, with average concentrations 1.23–1.71 times higher than local soil background values. Among them Ni, Cr and Cu were of special concern and they may pose adverse biological effects. By calculating enrichment factor (EF), it was found that the trace metal accumulation was still mainly ascribed to natural weathering processes, but anthropogenic contribution could represent up to 40.09% of total sediment content. For Pb, geochemical and isotopic approaches gave very similar anthropogenic contributions. Principal component analysis (PCA) further suggested that the anthropogenic Pb, Cu, Cr and Ni inputs were mostly related to the regional atmospheric deposition of industrial emissions and gasoline combustion, which had a strong affinity for iron oxides in the sediments. Concerning Cd, however, it mainly originated from local fertilizer applications and was controlled by sediment carbonates. - Graphical abstract: The trace metal accumulation was mainly ascribed to natural weathering processes, but anthropogenic contribution could represent up to 40.09% of total sediment content. Anthropogenic Pb, Cu, Cr and Ni mostly came from atmospheric deposition, while fertilizer application was the main anthropogenic source of Cd. - Highlights: • Trace metals have accumulated in the Naolihe sediments. • Natural weathering was still a major contributor to metal accumulation. • Anthropogenic Pb, Cu, Cr and Ni mostly came from atmospheric deposition. • Local fertilizer application was the main

Anthropogenic CO2 distribution in the North Pacific ocean

Energy Technology Data Exchange (ETDEWEB)

Chen, C [National Sun Yat-Sen University, Kaohsiung (Taiwan, Province of China)

1993-06-01

This paper discusses the penetration depth of anthropogenic CO2 in the North Pacific Ocean based on carbonate data in the literature. The carbonate data in the literature were used to supplement the tracer data showing oceanic mixing features for waters formed in the last 140 years. The deepest penetration over 2,000m was found in the northwest North Pacific. On the other hand, the shallowest penetration to less than 400m was found in the eastern equatorial Pacific. Consequently, it was suggested that penetration depth of anthropogenic CO2 has been controlled by such factors as deep water formation in the Northwest Pacific, upwelling in the equatorial Pacific, and vertical mixing in the western boundary areas. It was revealed that these results are in harmony well with results implied from tritium, C-14, and freons distributions. The total inventory of excess carbon in the North Pacific was 14.7[plus minus]4[times]10[sup 15]g around 1980. 48 refs., 10 figs.

Nuclear Renaissance in an Era of Anthropogenic Climate Change

International Nuclear Information System (INIS)

Bird, John

2008-01-01

This paper substantiates the anthropogenic origin of climate change, demonstrates the resulting consequences, and thereby establishes the need for a nuclear renaissance over the next thirty years. First, the mechanisms behind the natural cycles in global warming, specifically, cycles of precession and eccentricity in Earth's orbit, as measured in ice cores, are compared to the mechanisms of anthropogenic warming, revealing the scientific basis for the observed correlation between carbon dioxide and temperature. Second, the resulting climate change is exemplified by key results from experiments performed by the author in the Arctic and at the South Geographic Pole, and the author's experience of Switzerland's costliest natural catastrophe - the flash flood of 2005. Third, although facing barriers such as research and development requirements, political will and public acceptance, the potential for nuclear power to triple to 1,000 GWe by 2050 would mitigate climate change by holding carbon dioxide concentration below 500 ppm, thereby challenging the younger nuclear generation to contribute to the most important issue facing humanity. (authors)

Natural and anthropogenic nitrogen uptake by bloom-forming macroalgae

International Nuclear Information System (INIS)

Thornber, Carol S.; DiMilla, Peter; Nixon, Scott W.; McKinney, Richard A.

2008-01-01

The frequency and duration of macroalgal blooms have increased in many coastal waters over the past several decades. We used field surveys and laboratory culturing experiments to examine the nitrogen content and δ 15 N values of Ulva and Gracilaria, two bloom-forming algal genera in Narragansett Bay, RI (USA). The northern end of this bay is densely populated with large sewage treatment plant nitrogen inputs; the southern end is more lightly populated and opens to the Atlantic Ocean. Field-collected Ulva varied in δ 15 N among sites, but with two exceptions had δ 15 N above 10 per mille , reflecting a significant component of heavy anthropogenic N. This variation was not correlated with a north-south gradient. Both Ulva and Gracilaria cultured in water from across Narragansett Bay also had high signals (δ 15 N = ∼14-17 per mille and 8-12 per mille , respectively). These results indicate that inputs of anthropogenic N can have far-reaching impacts throughout estuaries

Natural and anthropogenic nitrogen uptake by bloom-forming macroalgae

Energy Technology Data Exchange (ETDEWEB)

Thornber, Carol S. [Department of Biological Sciences, 100 Flagg Road, University of Rhode Island, Kingston, RI 02881 (United States)], E-mail: thornber@uri.edu; DiMilla, Peter; Nixon, Scott W. [Graduate School of Oceanography, University of Rhode Island, South Ferry Road, Narragansett, RI 02881 (United States); McKinney, Richard A. [US Environmental Protection Agency, Atlantic Ecology Division, 27 Tarzwell Drive, Narragansett, RI 02882 (United States)

2008-02-15

The frequency and duration of macroalgal blooms have increased in many coastal waters over the past several decades. We used field surveys and laboratory culturing experiments to examine the nitrogen content and {delta}{sup 15}N values of Ulva and Gracilaria, two bloom-forming algal genera in Narragansett Bay, RI (USA). The northern end of this bay is densely populated with large sewage treatment plant nitrogen inputs; the southern end is more lightly populated and opens to the Atlantic Ocean. Field-collected Ulva varied in {delta}{sup 15}N among sites, but with two exceptions had {delta}{sup 15}N above 10 per mille , reflecting a significant component of heavy anthropogenic N. This variation was not correlated with a north-south gradient. Both Ulva and Gracilaria cultured in water from across Narragansett Bay also had high signals ({delta}{sup 15}N = {approx}14-17 per mille and 8-12 per mille , respectively). These results indicate that inputs of anthropogenic N can have far-reaching impacts throughout estuaries.

Natural and anthropogenic nitrogen uptake by bloom-forming macroalgae.

Science.gov (United States)

Thornber, Carol S; DiMilla, Peter; Nixon, Scott W; McKinney, Richard A

2008-02-01

The frequency and duration of macroalgal blooms have increased in many coastal waters over the past several decades. We used field surveys and laboratory culturing experiments to examine the nitrogen content and delta(15)N values of Ulva and Gracilaria, two bloom-forming algal genera in Narragansett Bay, RI (USA). The northern end of this bay is densely populated with large sewage treatment plant nitrogen inputs; the southern end is more lightly populated and opens to the Atlantic Ocean. Field-collected Ulva varied in delta(15)N among sites, but with two exceptions had delta(15)N above 10 per thousand, reflecting a significant component of heavy anthropogenic N. This variation was not correlated with a north-south gradient. Both Ulva and Gracilaria cultured in water from across Narragansett Bay also had high signals (delta(15)N= approximately 14-17 per thousand and 8-12 per thousand, respectively). These results indicate that inputs of anthropogenic N can have far-reaching impacts throughout estuaries.