Advances in Ecological Speciation: an integrative approach.

Science.gov (United States)

Faria, Rui; Renaut, Sebastien; Galindo, Juan; Pinho, Catarina; Melo-Ferreira, José; Melo, Martim; Jones, Felicity; Salzburger, Walter; Schluter, Dolph; Butlin, Roger

2014-02-01

The role of natural selection in promoting reproductive isolation has received substantial renewed interest within the last two decades. As a consequence, the study of ecological speciation has become an extremely productive research area in modern evolutionary biology. Recent innovations in sequencing technologies offer an unprecedented opportunity to study the mechanisms involved in ecological speciation. Genome scans provide significant insights but have some important limitations; efforts are needed to integrate them with other approaches to make full use of the sequencing data deluge. An international conference 'Advances in Ecological Speciation' organized by the University of Porto (Portugal) aimed to review current progress in ecological speciation. Using some of the examples presented at the conference, we highlight the benefits of integrating ecological and genomic data and discuss different mechanisms of parallel evolution. Finally, future avenues of research are suggested to advance our knowledge concerning the role of natural selection in the establishment of reproductive isolation during ecological speciation. © 2013 John Wiley & Sons Ltd.

Long-term feeding ecology and habitat use in harbour porpoises Phocoena phocoena from Scandinavian waters inferred from trace elements and stable isotopes

Directory of Open Access Journals (Sweden)

Gobert Sylvie

2007-01-01

Full Text Available Abstract Background We investigated the feeding ecology and habitat use of 32 harbour porpoises by-caught in 4 localities along the Scandinavian coast from the North Sea to the Barents Sea using time-integrative markers: stable isotopes (δ13C, δ15N and trace elements (Zn, Cu, Fe, Se, total Hg and Cd, in relation to habitat characteristics (bathymetry and geographic position (latitude. Results Among the trace elements analysed, only Cd, with an oceanic specific food origin, was found to be useful as an ecological tracer. All other trace elements studied were not useful, most likely because of physiological regulation and/or few specific sources in the food web. The δ13C, δ15N signatures and Cd levels were highly correlated with each other, as well as with local bathymetry and geographic position (latitude. Variation in the isotopic ratios indicated a shift in harbour porpoise's feeding habits from pelagic prey species in deep northern waters to more coastal and/or demersal prey in the relatively shallow North Sea and Skagerrak waters. This result is consistent with stomach content analyses found in the literature. This shift was associated with a northward Cd-enrichment which provides further support to the Cd 'anomaly' previously reported in polar waters and suggests that porpoises in deep northern waters include Cd-contaminated prey in their diet, such as oceanic cephalopods. Conclusion As stable isotopes and Cd provide information in the medium and the long term respectively, the spatial variation found, shows that harbour porpoises experience different ecological regimes during the year along the Scandinavian coasts, adapting their feeding habits to local oceanographic conditions, without performing extensive migration.

Long-term feeding ecology and habitat use in harbour porpoises Phocoena phocoena from Scandinavian waters inferred from trace elements and stable isotopes.

Science.gov (United States)

Fontaine, Michaël C; Tolley, Krystal A; Siebert, Ursula; Gobert, Sylvie; Lepoint, Gilles; Bouquegneau, Jean-Marie; Das, Krishna

2007-01-17

We investigated the feeding ecology and habitat use of 32 harbour porpoises by-caught in 4 localities along the Scandinavian coast from the North Sea to the Barents Sea using time-integrative markers: stable isotopes (delta13C, delta15N) and trace elements (Zn, Cu, Fe, Se, total Hg and Cd), in relation to habitat characteristics (bathymetry) and geographic position (latitude). Among the trace elements analysed, only Cd, with an oceanic specific food origin, was found to be useful as an ecological tracer. All other trace elements studied were not useful, most likely because of physiological regulation and/or few specific sources in the food web. The delta13C, delta15N signatures and Cd levels were highly correlated with each other, as well as with local bathymetry and geographic position (latitude). Variation in the isotopic ratios indicated a shift in harbour porpoise's feeding habits from pelagic prey species in deep northern waters to more coastal and/or demersal prey in the relatively shallow North Sea and Skagerrak waters. This result is consistent with stomach content analyses found in the literature. This shift was associated with a northward Cd-enrichment which provides further support to the Cd 'anomaly' previously reported in polar waters and suggests that porpoises in deep northern waters include Cd-contaminated prey in their diet, such as oceanic cephalopods. As stable isotopes and Cd provide information in the medium and the long term respectively, the spatial variation found, shows that harbour porpoises experience different ecological regimes during the year along the Scandinavian coasts, adapting their feeding habits to local oceanographic conditions, without performing extensive migration.

Surface oceanographic fronts influencing deep-sea biological activity: Using fish stable isotopes as ecological tracers

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Louzao, Maite; Navarro, Joan; Delgado-Huertas, Antonio; de Sola, Luis Gil; Forero, Manuela G.

2017-06-01

Ecotones can be described as transition zones between neighbouring ecological systems that can be shaped by environmental gradients over a range of space and time scales. In the marine environment, the detection of ecotones is complex given the highly dynamic nature of marine systems and the paucity of empirical data over ocean-basin scales. One approach to overcome these limitations is to use stable isotopes from animal tissues since they can track spatial oceanographic variability across marine systems and, in turn, can be used as ecological tracers. Here, we analysed stable isotopes of deep-sea fishes to assess the presence of ecological discontinuities across the western Mediterranean. We were specifically interested in exploring the connection between deep-sea biological activity and particular oceanographic features (i.e., surface fronts) occurring in the pelagic domain. We collected samples for three different abundant deep-sea species in May 2004 from an experimental oceanographic trawling cruise (MEDITS): the Mictophydae jewel lanternfish Lampanyctus crocodilus and two species of the Gadidae family, the silvery pout Gadiculus argenteus and the blue whiting Micromesistius poutassou. The experimental survey occurred along the Iberian continental shelf and the upper and middle slopes, from the Strait of Gibraltar in the SW to the Cape Creus in the NE. The three deep-sea species were highly abundant throughout the study area and they showed geographic variation in their isotopic values, with decreasing values from north to south disrupted by an important change point around the Vera Gulf. Isotopic latitudinal gradients were explained by pelagic oceanographic conditions along the study area and confirm the existence of an ecotone at the Vera Gulf. This area could be considered as an oceanographic boundary where waters of Atlantic origin meet Mediterranean surface waters forming important frontal structures such as the Almeria-Oran front. In fact, our results

Tracking the rise of eukaryotes to ecological dominance with zinc isotopes.

Science.gov (United States)

Isson, Terry T; Love, Gordon D; Dupont, Christopher L; Reinhard, Christopher T; Zumberge, Alex J; Asael, Dan; Gueguen, Bleuenn; McCrow, John; Gill, Ben C; Owens, Jeremy; Rainbird, Robert H; Rooney, Alan D; Zhao, Ming-Yu; Stueeken, Eva E; Konhauser, Kurt O; John, Seth G; Lyons, Timothy W; Planavsky, Noah J

2018-06-05

The biogeochemical cycling of zinc (Zn) is intimately coupled with organic carbon in the ocean. Based on an extensive new sedimentary Zn isotope record across Earth's history, we provide evidence for a fundamental shift in the marine Zn cycle ~800 million years ago. We discuss a wide range of potential drivers for this transition and propose that, within available constraints, a restructuring of marine ecosystems is the most parsimonious explanation for this shift. Using a global isotope mass balance approach, we show that a change in the organic Zn/C ratio is required to account for observed Zn isotope trends through time. Given the higher affinity of eukaryotes for Zn relative to prokaryotes, we suggest that a shift toward a more eukaryote-rich ecosystem could have provided a means of more efficiently sequestering organic-derived Zn. Despite the much earlier appearance of eukaryotes in the microfossil record (~1700 to 1600 million years ago), our data suggest a delayed rise to ecological prominence during the Neoproterozoic, consistent with the currently accepted organic biomarker records. © 2018 John Wiley & Sons Ltd.

Using stable isotopes to track the effects of deforestation on small-mammal ecology in the Pacific Northwest over the last 100 years

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Packard, N. R.; Cotton, J. M.; Smiley, T. M.; Terry, R. C.

2017-12-01

Landscape, land-use, and climate change are important factors in determining ecosystem change over a range of spatio-temporal scales. For example, within small-mammal communities, the spread of agriculture, rapid urbanization, and deforestation have been shown to alter species composition and diet, thus potentially disrupting ecological interactions and reshaping ecosystems. Small mammals integrate the isotopic composition of their diet and drinking water into their hair and therefore serve as useful proxies for vegetation and water resources in their habitat. To better understand how forest loss and land-cover change influence small-mammal ecology in the Pacific Northwest (PNW), we analyzed the hydrogen (H) and oxygen (O) isotopic composition of hair from historical Peromyscus maniculatus (North American deer mouse) specimens housed in natural history museums across the country. While deforestation along the east coast occurred hundreds of years ago, the loss of forests on the west coast occurred more recently, beginning around 1930. We use early 20th century specimens of this widespread and abundant generalist species to better understand ecosystem changes that occurred over the past 100 years of local and regional deforestation. Changing forest composition and structure during deforestation can influence both broad-scale hydrological cycling and local ecosystems. Variation in O and H isotopic composition corresponds to changes in the hydrological cycle, such as changes in the source and amount of precipitation, and changes in the moisture conditions in local ecosystems. We will present this spatial and temporal variability in the form of isoscapes, or δ18O and δD isotope landscape models, of P. maniculatus hair in the western forests of the PNW through time. Investigating isotopic signatures in small mammals can help us better understand ecosystem response to anthropogenic land-use and climate change.

Ecological niche of Neanderthals from Spy Cave revealed by nitrogen isotopes of individual amino acids in collagen.

Science.gov (United States)

Naito, Yuichi I; Chikaraishi, Yoshito; Drucker, Dorothée G; Ohkouchi, Naohiko; Semal, Patrick; Wißing, Christoph; Bocherens, Hervé

2016-04-01

This study provides a refined view on the diet and ecological niche of Neanderthals. The traditional view is that Neanderthals obtained most of their dietary protein from terrestrial animals, especially from large herbivores that roamed the open landscapes. Evidence based on the conventional carbon and nitrogen isotopic composition of bulk collagen has supported this view, although recent findings based on plant remains in the tooth calculus, microwear analyses, and small game and marine animal remains from archaeological sites have raised some questions regarding this assumption. However, the lack of a protein source other than meat in the Neanderthal diet may be due to methodological difficulties in defining the isotopic composition of plants. Based on the nitrogen isotopic composition of glutamic acid and phenylalanine in collagen for Neanderthals from Spy Cave (Belgium), we show that i) there was an inter-individual dietary heterogeneity even within one archaeological site that has not been evident in bulk collagen isotopic compositions, ii) they occupied an ecological niche different from those of hyenas, and iii) they could rely on plants for up to ∼20% of their protein source. These results are consistent with the evidence found of plant consumption by the Spy Neanderthals, suggesting a broader subsistence strategy than previously considered. Copyright © 2016 Elsevier Ltd. All rights reserved.

Samdrup Jongkhar Initiative : a Model of Integrated Ecologically ...

International Development Research Centre (IDRC) Digital Library (Canada)

Samdrup Jongkhar Initiative : a Model of Integrated Ecologically-friendly ... which endeavors to integrate social, economic, cultural and environmental objectives. ... Brown Cloud penetrates Bhutan : ambient air quality and trans-boundary ...

Quantifying an Integral Ecology Framework: A Case Study of the Riverina, Australia

Science.gov (United States)

Wheeler, Sarah A.; Haensch, Juliane; Edwards, Jane; Schirmer, Jackie; Zuo, Alec

2018-02-01

Communities in Australia's Murray-Darling Basin face the challenge of trying to achieve social, economic, and environmental sustainability; but experience entrenched conflict about the best way to achieve a sustainable future, especially for small rural communities. Integral ecology is a philosophical concept that seeks to address community, economic, social, and environmental sustainability simultaneously. Its inclusive processes are designed to reduce stakeholder conflict. However, to date the application of the integral ecology concept has been largely qualitative in nature. This study developed a quantitative integral ecology framework, and applied this framework to a case study of the Riverina, in the Murray-Darling Basin. Seventy-seven community-focused initiatives were assessed, ranked, and quantified. The majority of the community-focused ranked initiatives did not exhibit all aspects of integral ecology. Initiatives typically prioritized either (1) economic and community development or (2) environmental health; rarely both together. The integral ecology framework developed here enables recommendations on future community initiatives and may provide a pathway for community leaders and other policy-makers to more readily apply integral ecology objectives. Further research refining the framework's operationalization, application and implementation to a wider-scale may enhance communities' capacity to develop and grow sustainably.

Social Ecological Model Analysis for ICT Integration

Science.gov (United States)

Zagami, Jason

2013-01-01

ICT integration of teacher preparation programmes was undertaken by the Australian Teaching Teachers for the Future (TTF) project in all 39 Australian teacher education institutions and highlighted the need for guidelines to inform systemic ICT integration approaches. A Social Ecological Model (SEM) was used to positively inform integration…

Methodological validation of the isotopic analysis of fossil bones and contributions to the paleo-ecological reconstitutions of the Upper Paleolithic of south-west France

International Nuclear Information System (INIS)

Drucker, D.

2001-04-01

A methodology for investigating fossil bone collagen carbon and nitrogen isotopic signatures has been established in order to obtain palaeo-ecological informations. The archaeological, biochemical and geochemical reliability has been estimated. Almost 500 animal and human specimens from southwestern France upper Palaeolithic sites ranging in age from 36,000 to 9,000 years BP have been treated. It has been demonstrated that different dietary resources were isotopically distinct, with a resolution better than the expectations. Small mammals have been distinguished from ungulates, and Reindeer, Horse and Bovines presented specific isotopic signatures. Moreover, isotopic differences have been evidenced between gregarious and solitary species. Time changes of ecological patterns have been described using the isotopic signatures of some mammal species. Biomass fluctuation and exploitation have been demonstrated during upper Palaeolithic. The methodology allowed to use the isotopic signatures of animal predators as a proxy for meat resources availability in the environment. This approach allows to investigate environmental global factors as well as human behaviour with a common tool. (author)

Evaluation of stream ecological integrity using litter decomposition and benthic invertebrates

Energy Technology Data Exchange (ETDEWEB)

Castela, Jose [Departamento de Zoologia and IMAR-CIC, Universidade de Coimbra, Largo Marques de Pombal, 3004-517 Coimbra (Portugal)], E-mail: jcccastela@gmail.com; Ferreira, Veronica [Departamento de Zoologia and IMAR-CIC, Universidade de Coimbra, Largo Marques de Pombal, 3004-517 Coimbra (Portugal)], E-mail: veronica@ci.uc.pt; Graca, Manuel A.S. [Departamento de Zoologia and IMAR-CIC, Universidade de Coimbra, Largo Marques de Pombal, 3004-517 Coimbra (Portugal)], E-mail: mgraca@ci.uc.pt

2008-05-15

Biomonitoring programs to access the ecological integrity of freshwaters tend to rely exclusively on structural parameters. Here we evaluated stream ecological integrity using (a) benthic macroinvertebrate derived metrics and a biotic index as measures of structural integrity and (b) oak litter decomposition and associated fungal sporulation rates as measures of functional integrity. The study was done at four sites (S1, S2, S3 and S4) along a downstream increasing phosphorus and habitat degradation gradient in a small stream. The biotic index, invertebrate metrics, invertebrate and fungal communities' structure and sporulation rates discriminated upstream and downstream sites. Decomposition rates classified sites S4 and S2 as having a compromised ecosystem functioning. Although both functional and structural approaches gave the same results for the most impacted site (S4), they were complementary for moderately impacted sites (S2 and S3), and we therefore support the need for incorporating functional measures in evaluations of stream ecological integrity. - This study supports the need for incorporating functional measures in evaluations of stream ecological integrity.

Evaluation of stream ecological integrity using litter decomposition and benthic invertebrates

International Nuclear Information System (INIS)

Castela, Jose; Ferreira, Veronica; Graca, Manuel A.S.

2008-01-01

Biomonitoring programs to access the ecological integrity of freshwaters tend to rely exclusively on structural parameters. Here we evaluated stream ecological integrity using (a) benthic macroinvertebrate derived metrics and a biotic index as measures of structural integrity and (b) oak litter decomposition and associated fungal sporulation rates as measures of functional integrity. The study was done at four sites (S1, S2, S3 and S4) along a downstream increasing phosphorus and habitat degradation gradient in a small stream. The biotic index, invertebrate metrics, invertebrate and fungal communities' structure and sporulation rates discriminated upstream and downstream sites. Decomposition rates classified sites S4 and S2 as having a compromised ecosystem functioning. Although both functional and structural approaches gave the same results for the most impacted site (S4), they were complementary for moderately impacted sites (S2 and S3), and we therefore support the need for incorporating functional measures in evaluations of stream ecological integrity. - This study supports the need for incorporating functional measures in evaluations of stream ecological integrity

Exploring the isotopic niche: isotopic variance, physiological incorporation, and the temporal dynamics of foraging

Directory of Open Access Journals (Sweden)

Justin Douglas Yeakel

2016-01-01

Full Text Available Consumer foraging behaviors are dynamic, changing in response to prey availability, seasonality, competition, and even the consumer's physiological state. The isotopic composition of a consumer is a product of these factors as well as the isotopic `landscape' of its prey, i.e. the isotopic mixing space. Stable isotope mixing models are used to back-calculate the most likely proportional contribution of a set of prey to a consumer's diet based on their respective isotopic distributions, however they are disconnected from ecological process. Here we build a mechanistic framework that links the ecological and physiological processes of an individual consumer to the isotopic distribution that describes its diet, and ultimately to the isotopic composition of its own tissues, defined as its `isotopic niche’. By coupling these processes, we systematically investigate under what conditions the isotopic niche of a consumer changes as a function of both the geometric properties of its mixing space and foraging strategies that may be static or dynamic over time. Results of our derivations reveal general insight into the conditions impacting isotopic niche width as a function of consumer specialization on prey, as well as the consumer's ability to transition between diets over time. We show analytically that moderate specialization on isotopically unique prey can serve to maximize a consumer's isotopic niche width, while temporally dynamic diets will tend to result in peak isotopic variance during dietary transitions. We demonstrate the relevance of our theoretical findings by examining a marine system composed of nine invertebrate species commonly consumed by sea otters. In general, our analytical framework highlights the complex interplay of mixing space geometry and consumer dietary behavior in driving expansion and contraction of the isotopic niche. Because this approach is established on ecological mechanism, it is well-suited for enhancing the

Stable isotope analysis in primatology: a critical review.

Science.gov (United States)

Sandberg, Paul A; Loudon, James E; Sponheimer, Matt

2012-11-01

Stable isotope analysis has become an important tool in ecology over the last 25 years. A wealth of ecological information is stored in animal tissues in the relative abundances of the stable isotopes of several elements, particularly carbon and nitrogen, because these isotopes navigate through ecological processes in predictable ways. Stable carbon and nitrogen isotopes have been measured in most primate taxonomic groups and have yielded information about dietary content, dietary variability, and habitat use. Stable isotopes have recently proven useful for addressing more fine-grained questions about niche dynamics and anthropogenic effects on feeding ecology. Here, we discuss stable carbon and nitrogen isotope systematics and critically review the published stable carbon and nitrogen isotope data for modern primates with a focus on the problems and prospects for future stable isotope applications in primatology. © 2012 Wiley Periodicals, Inc.

Social-ecological research in urban natural areas: an emergent process for integration

Science.gov (United States)

Michelle L. Johnson; D. S. Novem Auyeung; Nancy F. Sonti; Clara C. Pregitzer; Heather L. McMillen; Richard Hallett; Lindsay K. Campbell; Helen M. Forgione; Mina Kim; Sarah Charlop-Powers; Erika S. Svendsen

2018-01-01

Understanding the structure and function of urban landscapes requires integrating social and ecological research. Here, we integrate parallel social and ecological assessments of natural areas within New York City. We examined social data (from a rapid assessment of park use and meaning, collected at a park zone level) alongside ecological data (froma plot-based...

Improved bacteriophage genome data is necessary for integrating viral and bacterial ecology.

Science.gov (United States)

Bibby, Kyle

2014-02-01

The recent rise in "omics"-enabled approaches has lead to improved understanding in many areas of microbial ecology. However, despite the importance that viruses play in a broad microbial ecology context, viral ecology remains largely not integrated into high-throughput microbial ecology studies. A fundamental hindrance to the integration of viral ecology into omics-enabled microbial ecology studies is the lack of suitable reference bacteriophage genomes in reference databases-currently, only 0.001% of bacteriophage diversity is represented in genome sequence databases. This commentary serves to highlight this issue and to promote bacteriophage genome sequencing as a valuable scientific undertaking to both better understand bacteriophage diversity and move towards a more holistic view of microbial ecology.

Integrating Social Science into the Long-Term Ecological Research (LTER) Network: Social Dimensions of Ecological Change and Ecological Dimensions of Social Change

Science.gov (United States)

Charles L. Redman; J. Morgan Grove; Lauren H. Kuby; Lauren H. Kuby

2004-01-01

The integration of the social sciences into long-term ecological research is an urgent priority. To address this need, a group of social, earth, and life scientists associated with the National Science Foundation's (NSF) Long-Term Ecological Research (LTER) Network have articulated a conceptual framework for understanding the human dimensions of ecological change...

Advancing the integration of history and ecology for conservation.

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Szabó, Péter; Hédl, Radim

2011-08-01

The important role of humans in the development of current ecosystems was recognized decades ago; however, the integration of history and ecology in order to inform conservation has been difficult. We identified four issues that hinder historical ecological research and considered possible solutions. First, differences in concepts and methods between the fields of ecology and history are thought to be large. However, most differences stem from miscommunication between ecologists and historians and are less substantial than is usually assumed. Cooperation can be achieved by focusing on the features ecology and history have in common and through understanding and acceptance of differing points of view. Second, historical ecological research is often hampered by differences in spatial and temporal scales between ecology and history. We argue that historical ecological research can only be conducted at extents for which sources in both disciplines have comparable resolutions. Researchers must begin by clearly defining the relevant scales for the given purpose. Third, periods for which quantitative historical sources are not easily accessible (before AD 1800) have been neglected in historical ecological research. Because data from periods before 1800 are as relevant to the current state of ecosystems as more recent data, we suggest that historical ecologists actively seek out data from before 1800 and apply analytic methods commonly used in ecology to these data. Fourth, humans are not usually considered an intrinsic ecological factor in current ecological research. In our view, human societies should be acknowledged as integral parts of ecosystems and societal processes should be recognized as driving forces of ecosystem change. © 2011 Society for Conservation Biology.

Integrated approaches to long-term studies of urban ecological systems

Science.gov (United States)

Nancy B. Grimm; J. Morgan Grove; Steward T.A. Pickett; Charles L. Redman

2000-01-01

Urban ecological systems present multiple challenges to ecologists—pervasive human impact and extreme heterogeneity of cities, and the need to integrate social and ecological approaches, concepts, and theory.

Integrated presentation of ecological risk from multiple stressors

Science.gov (United States)

Goussen, Benoit; Price, Oliver R.; Rendal, Cecilie; Ashauer, Roman

2016-10-01

Current environmental risk assessments (ERA) do not account explicitly for ecological factors (e.g. species composition, temperature or food availability) and multiple stressors. Assessing mixtures of chemical and ecological stressors is needed as well as accounting for variability in environmental conditions and uncertainty of data and models. Here we propose a novel probabilistic ERA framework to overcome these limitations, which focusses on visualising assessment outcomes by construct-ing and interpreting prevalence plots as a quantitative prediction of risk. Key components include environmental scenarios that integrate exposure and ecology, and ecological modelling of relevant endpoints to assess the effect of a combination of stressors. Our illustrative results demonstrate the importance of regional differences in environmental conditions and the confounding interactions of stressors. Using this framework and prevalence plots provides a risk-based approach that combines risk assessment and risk management in a meaningful way and presents a truly mechanistic alternative to the threshold approach. Even whilst research continues to improve the underlying models and data, regulators and decision makers can already use the framework and prevalence plots. The integration of multiple stressors, environmental conditions and variability makes ERA more relevant and realistic.

Integrated presentation of ecological risk from multiple stressors.

Science.gov (United States)

Goussen, Benoit; Price, Oliver R; Rendal, Cecilie; Ashauer, Roman

2016-10-26

Current environmental risk assessments (ERA) do not account explicitly for ecological factors (e.g. species composition, temperature or food availability) and multiple stressors. Assessing mixtures of chemical and ecological stressors is needed as well as accounting for variability in environmental conditions and uncertainty of data and models. Here we propose a novel probabilistic ERA framework to overcome these limitations, which focusses on visualising assessment outcomes by construct-ing and interpreting prevalence plots as a quantitative prediction of risk. Key components include environmental scenarios that integrate exposure and ecology, and ecological modelling of relevant endpoints to assess the effect of a combination of stressors. Our illustrative results demonstrate the importance of regional differences in environmental conditions and the confounding interactions of stressors. Using this framework and prevalence plots provides a risk-based approach that combines risk assessment and risk management in a meaningful way and presents a truly mechanistic alternative to the threshold approach. Even whilst research continues to improve the underlying models and data, regulators and decision makers can already use the framework and prevalence plots. The integration of multiple stressors, environmental conditions and variability makes ERA more relevant and realistic.

Getting the message across: using ecological integrity to communicate with resource managers

Science.gov (United States)

Mitchell, Brian R.; Tierney, Geraldine L.; Schweiger, E. William; Miller, Kathryn M.; Faber-Langendoen, Don; Grace, James B.

2014-01-01

This chapter describes and illustrates how concepts of ecological integrity, thresholds, and reference conditions can be integrated into a research and monitoring framework for natural resource management. Ecological integrity has been defined as a measure of the composition, structure, and function of an ecosystem in relation to the system’s natural or historical range of variation, as well as perturbations caused by natural or anthropogenic agents of change. Using ecological integrity to communicate with managers requires five steps, often implemented iteratively: (1) document the scale of the project and the current conceptual understanding and reference conditions of the ecosystem, (2) select appropriate metrics representing integrity, (3) define externally verified assessment points (metric values that signify an ecological change or need for management action) for the metrics, (4) collect data and calculate metric scores, and (5) summarize the status of the ecosystem using a variety of reporting methods. While we present the steps linearly for conceptual clarity, actual implementation of this approach may require addressing the steps in a different order or revisiting steps (such as metric selection) multiple times as data are collected. Knowledge of relevant ecological thresholds is important when metrics are selected, because thresholds identify where small changes in an environmental driver produce large responses in the ecosystem. Metrics with thresholds at or just beyond the limits of a system’s range of natural variability can be excellent, since moving beyond the normal range produces a marked change in their values. Alternatively, metrics with thresholds within but near the edge of the range of natural variability can serve as harbingers of potential change. Identifying thresholds also contributes to decisions about selection of assessment points. In particular, if there is a significant resistance to perturbation in an ecosystem, with threshold

Integrating ecological restoration into CDM forestry projects

International Nuclear Information System (INIS)

Ma, Maohua; Haapanen, Toni; Singh, Ram Babu; Hietala, Reija

2014-01-01

Highlights: • Concerns and issues in sustainability of CDM forestry projects are reviewed. • Ecological restoration is suggested to be integrated in the CDM framework. • As an ecosystem supporting service, soil restoration on degraded land is of primary importance. • Regenerating forests naturally rather than through monoculture plantations is suggested. • Potential social impacts of ecological restoration are discussed. - Abstract: The Clean Development Mechanism (CDM) is proposed to reduce greenhouse gas emissions and promote sustainable development. CDM forestry projects should contribute to mitigation of climate change through afforestation and reforestation (A/R) activities on degraded land in developing countries. However, like other types of CDM projects, the forestry projects have encountered a number of concerns and critiques. Appropriate approaches and concrete aims to achieve long-term sustainability have been lacking, and reforms have therefore been called for. The aims of this paper are to examine the published information relevant to these concerns, and frame appropriate approaches for a more sustainable CDM. In this review, as a first step to tackle some of these issues, ecological restoration is suggested for integration into the CDM framework. Essentially, this involves the restoration of ecosystem supporting service (soil restoration), upon which forests regenerate naturally rather than establishing monoculture plantations. In this way, forestry projects would bring cost-effective opportunities for multiple ecosystem services. Potential approaches, necessary additions to the monitoring plans, and social impacts of ecological restoration in CDM projects are discussed

Integrating technologies for scalable ecology and conservation

NARCIS (Netherlands)

Marvin, D.C.; Koh, L.P.; Lynam, A.J.; Wich, S.; Davies, A.B.; Krishnamurthy, R.; Stokes, E.; Starkey, R.; Asner, G.P.

Integration of multiple technologies greatly increases the spatial and temporal scales over which ecological patterns and processes can be studied, and threats to protected ecosystems can be identified and mitigated. A range of technology options relevant to ecologists and conservation practitioners

Recent changes in Central European landscapes: An integrative ecological approach

Czech Academy of Sciences Publication Activity Database

Těšitel, Jan; Kučera, Tomáš

2005-01-01

Roč. 24, č. 1 (2005), s. 3-6 ISSN 1335-342X Institutional research plan: CEZ:AV0Z60870520 Keywords : integrative ecological approach * transdisciplinarity * interdisciplinarity * landscape ecology Subject RIV: DO - Wilderness Conservation Impact factor: 0.085, year: 2005

Assessment of ecological Process in Chashma wetland and its surroundings using isotopic techniques

International Nuclear Information System (INIS)

Latif, Z.; Rasul, B.; Ahmad, M.; Fazil, M.; Butt, S.; Qureshi, R.M.; Akram, W.; Choudhry, M.A.

2010-03-01

Wetlands are ecologically and functionally substantial elements of the water environment. Pakistan presently has 19 sites designated as Wetlands of International Importance (Rarnsar Sites), which are associated with essential ecosystem services and often support a wide variety of natural ecologic resources that are significant in socio-economic development. The main objective is to apply geochemical and isotopic techniques in the estimation of water to and from Chashma wetlands, and to provide insight on how protection and management of wetlands might improve the water quality and associated ecological functions. Sampling is performed from fresh water wetland at Chashma Barrage Punjab site before Monsoon. The site is comprised of a large barrage, a water storage reservoir and a series of embankments which divide the reservoir into five shallow lakes at low water levels. The study area is located on the left bank of the river Indus between latitudes 32 deg. 11' 43' and 32 deg. 38' 25' north and longitudes 71 deg. 23' 53' and 71 deg. 45' 40' east. Aqueous samples for /sup 2/H, ISO and /sup 13/C analysis, plant and soil samples for /sup 2/H, ISO and /sup 13/C analysis and fish samples to study /sup 13/C-isotopic fractionation in different organs of various fish are collected from Chashma Lake. The EC of some parts of the Chashma Lake is enriched due to salt dissolution and evaporation. Isotopic composition of Lake gamma /sup 18/O and gamma /sup 2/H is enriched due to evaporation. Gamma /sup 13/C values of bicarbonates of water samples have a trend towards sediment carbonates dissolution and high dissolved oxygen concentration is due to the photosynthesis phenomena of algae and aqueous plants. It is observed that gamma/sup 13/C of leaves in most of the C-3 and C-4 plants is more depleted as compare to gamma/sup 13/C of stem. A vast variety of fishes are distributed in the rivers, lakes etc. depending upon water movement, temperature, oxygen content and characteristics

The Encyclical Laudato Si': integral ecology, gender and deep ecology

Directory of Open Access Journals (Sweden)

José Eustáquio Diniz Alves

2015-09-01

Full Text Available Pope Jorge Mario Bergoglio released the "Encyclical Laudato Si': on the care of common home" on June 18, 2015, the same day that the National Oceanic and Atmospheric Administration (NOAA has shown that the temperature of Earth continues increasing and that May of 2015 was Earth's warmest month, since 1880. By endorsing the scientific knowledge in relation to anthropogenic factors on global warming and by defending actions to confront the causes of climate change and ecosystem degradation, the Holy See has taken a key step to put Catholics at the forefront of global ecological struggle and to encourage the signing of the global treaty to replace the Kyoto Protocol at the 21st Conference of the Parties (COP-21, that will take place in December in Paris. But the encyclical of Pope Francis proposes a larger task that is to protect the poorest of the poor countries, addressing jointly the human environment and the natural environment from the perspective of an integral ecology. The purpose of this paper is to analyze the advances and limitations of the propositions of the encyclical Laudato Si ' and to expand the dialogue on gender relations and deep ecology.

Pre-whaling genetic diversity and population ecology in eastern Pacific gray whales: insights from ancient DNA and stable isotopes.

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S Elizabeth Alter

Full Text Available Commercial whaling decimated many whale populations, including the eastern Pacific gray whale, but little is known about how population dynamics or ecology differed prior to these removals. Of particular interest is the possibility of a large population decline prior to whaling, as such a decline could explain the ~5-fold difference between genetic estimates of prior abundance and estimates based on historical records. We analyzed genetic (mitochondrial control region and isotopic information from modern and prehistoric gray whales using serial coalescent simulations and Bayesian skyline analyses to test for a pre-whaling decline and to examine prehistoric genetic diversity, population dynamics and ecology. Simulations demonstrate that significant genetic differences observed between ancient and modern samples could be caused by a large, recent population bottleneck, roughly concurrent with commercial whaling. Stable isotopes show minimal differences between modern and ancient gray whale foraging ecology. Using rejection-based Approximate Bayesian Computation, we estimate the size of the population bottleneck at its minimum abundance and the pre-bottleneck abundance. Our results agree with previous genetic studies suggesting the historical size of the eastern gray whale population was roughly three to five times its current size.

Mess management in microbial ecology: Rhetorical processes of disciplinary integration

Science.gov (United States)

McCracken, Christopher W.

As interdisciplinary work becomes more common in the sciences, research into the rhetorical processes mediating disciplinary integration becomes more vital. This dissertation, which takes as its subject the integration of microbiology and ecology, combines a postplural approach to rhetoric of science research with Victor Turner's "social drama" analysis and a third-generation activity theory methodological framework to identify conceptual and practical conflicts in interdisciplinary work and describe how, through visual and verbal communication, scientists negotiate these conflicts. First, to understand the conflicting disciplinary principles that might impede integration, the author conducts a Turnerian analysis of a disciplinary conflict that took place in the 1960s and 70s, during which American ecologists and biologists debated whether they should participate in the International Biological Program (IBP). Participation in the IBP ultimately contributed to the emergence of ecology as a discipline distinct from biology, and Turnerian social drama analysis of the debate surrounding participation lays bare the conflicting principles separating biology and ecology. Second, to answer the question of how these conflicting principles are negotiated in practice, the author reports on a yearlong qualitative study of scientists working in a microbial ecology laboratory. Focusing specifically on two case studies from this fieldwork that illustrate the key concept of textually mediated disciplinary integration, the author's analysis demonstrates how scientific objects emerge in differently situated practices, and how these objects manage to cohere despite their multiplicity through textually mediated rhetorical processes of calibration and alignment.

Not all jellyfish are equal: isotopic evidence for inter- and intraspecific variation in jellyfish trophic ecology

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Nicholas E.C. Fleming

2015-07-01

Full Text Available Jellyfish are highly topical within studies of pelagic food-webs and there is a growing realisation that their role is more complex than once thought. Efforts being made to include jellyfish within fisheries and ecosystem models are an important step forward, but our present understanding of their underlying trophic ecology can lead to their oversimplification in these models. Gelatinous zooplankton represent a polyphyletic assemblage spanning >2,000 species that inhabit coastal seas to the deep-ocean and employ a wide variety of foraging strategies. Despite this diversity, many contemporary modelling approaches include jellyfish as a single functional group feeding at one or two trophic levels at most. Recent reviews have drawn attention to this issue and highlighted the need for improved communication between biologists and theoreticians if this problem is to be overcome. We used stable isotopes to investigate the trophic ecology of three co-occurring scyphozoan jellyfish species (Aurelia aurita, Cyanea lamarckii and C. capillata within a temperate, coastal food-web in the NE Atlantic. Using information on individual size, time of year and δ13C and δ15N stable isotope values, we examined: (1 whether all jellyfish could be considered as a single functional group, or showed distinct inter-specific differences in trophic ecology; (2 Were size-based shifts in trophic position, found previously in A. aurita, a common trait across species?; (3 When considered collectively, did the trophic position of three sympatric species remain constant over time? Differences in δ15N (trophic position were evident between all three species, with size-based and temporal shifts in δ15N apparent in A. aurita and C. capillata. The isotopic niche width for all species combined increased throughout the season, reflecting temporal shifts in trophic position and seasonal succession in these gelatinous species. Taken together, these findings support previous

Not all jellyfish are equal: isotopic evidence for inter- and intraspecific variation in jellyfish trophic ecology.

Science.gov (United States)

Fleming, Nicholas E C; Harrod, Chris; Newton, Jason; Houghton, Jonathan D R

2015-01-01

Jellyfish are highly topical within studies of pelagic food-webs and there is a growing realisation that their role is more complex than once thought. Efforts being made to include jellyfish within fisheries and ecosystem models are an important step forward, but our present understanding of their underlying trophic ecology can lead to their oversimplification in these models. Gelatinous zooplankton represent a polyphyletic assemblage spanning >2,000 species that inhabit coastal seas to the deep-ocean and employ a wide variety of foraging strategies. Despite this diversity, many contemporary modelling approaches include jellyfish as a single functional group feeding at one or two trophic levels at most. Recent reviews have drawn attention to this issue and highlighted the need for improved communication between biologists and theoreticians if this problem is to be overcome. We used stable isotopes to investigate the trophic ecology of three co-occurring scyphozoan jellyfish species (Aurelia aurita, Cyanea lamarckii and C. capillata) within a temperate, coastal food-web in the NE Atlantic. Using information on individual size, time of year and δ (13)C and δ (15)N stable isotope values, we examined: (1) whether all jellyfish could be considered as a single functional group, or showed distinct inter-specific differences in trophic ecology; (2) Were size-based shifts in trophic position, found previously in A. aurita, a common trait across species?; (3) When considered collectively, did the trophic position of three sympatric species remain constant over time? Differences in δ (15)N (trophic position) were evident between all three species, with size-based and temporal shifts in δ (15)N apparent in A. aurita and C. capillata. The isotopic niche width for all species combined increased throughout the season, reflecting temporal shifts in trophic position and seasonal succession in these gelatinous species. Taken together, these findings support previous assertions

Stable isotope analysis indicates a lack of inter- and intra-specific dietary redundancy among ecologically important coral reef fishes

Science.gov (United States)

Plass-Johnson, J. G.; McQuaid, C. D.; Hill, J. M.

2013-06-01

Parrotfish are critical consumers on coral reefs, mediating the balance between algae and corals, and are often categorised into three functional groups based on adult morphology and feeding behaviour. We used stable isotope analysis (δ13C, δ15N) to investigate size-related ontogenetic dietary changes in multiple species of parrotfish on coral reefs around Zanzibar. We compared signatures among species and functional groups (scrapers, excavators and browsers) as well as ontogenetic stages (immature, initial and terminal phase) within species. Stable isotope analysis suggests that ontogenetic dietary shifts occurred in seven of the nine species examined; larger individuals had enriched δ13C values, with no relationship between size and δ15N. The relationship between fish length and δ13C signature was maintained when species were categorised as scrapers and excavators, but was more pronounced for scrapers than excavators, indicating stronger ontogenetic changes. Isotopic mixing models classified the initial phase of both the most abundant excavator ( Chlorurus sordidus) as a scraper and the immature stage of the scraper Scarus ghobban (the largest species) as an excavator, indicating that diet relates to size rather than taxonomy. The results indicate that parrotfish may show similar intra-group changes in diet with length, but that their trophic ecology is more complex than suggested by morphology alone. Stable isotope analyses indicate that feeding ecology may differ among species within functional groups, and according to ontogenetic stage within a species.

An integrated framework for health and ecological risk assessment

International Nuclear Information System (INIS)

Suter, Glenn W.; Vermeire, Theo; Munns, Wayne R.; Sekizawa, Jun

2005-01-01

The worldHealth Organization's (WHO's) International Program for Chemical Safety has developed a framework for performing risk assessments that integrate the assessment of risks to human health and risks to nonhuman organisms and ecosystems. The WHO's framework recognizes that stakeholders and risk managers have their own processes that are parallel to the scientific process of risk assessment and may interact with the risk assessment at various points, depending on the context. Integration of health and ecology provides consistent expressions of assessment results, incorporates the interdependence of humans and the environment, uses sentinel organisms, and improves the efficiency and quality of assessments relative to independent human health and ecological risk assessments. The advantage of the framework to toxicologists lies in the opportunity to use understanding of toxicokinetics and toxicodynamics to inform the integrated assessment of all exposed species

Groundwater Inputs to Rivers: Hydrological, Biogeochemical and Ecological Effects Inferred by Environmental Isotopes

Energy Technology Data Exchange (ETDEWEB)

Stellato, L. [Centre for Isotopic Research on Cultural and Environmental heritage (CIRCE), Seconda Universita degli Studi di Napoli, Caserta (Italy); Newman, B. D. [Isotope Hydrology Section, International Atomic Energy Agency, Vienna (Austria)

2013-05-15

In an effort to improve river management, numerous studies over the past two decades have supported the concept that river water and groundwater need to be considered together, as part of a hydrologic continuum. In particular, studies of the interface between surface water and groundwater (the hyporheic zone) have seen the tight collaboration of catchment hydrologists and stream ecologists in order to elucidate processes affecting stream functioning. Groundwater and surface waters interact at different spatial and temporal scales depending on system hydrology and geomorphology, which in turn influence nutrient cycling and in-stream ecology in relation to climatic, geologic, biotic and anthropogenic factors. In this paper, groundwater inputs to rivers are explored from two different and complementary perspectives: the hydrogeological, describing the generally acknowledged mechanisms of streamflow generation and the main factors controlling stream-aquifer interactions, and the ecologic, describing the processes occurring at the hyporheical and the riparian zones and their possible effects on stream functioning and on nutrient cycling, also taking into consideration the impact of human activities. Groundwater inflows to rivers can be important controls on hot moment/hot spot type biogeochemical behaviors. A description of the common methods used to assess these processes is provided emphasizing tracer methods (including physical, chemical and isotopic). In particular, naturally occurring isotopes are useful tools to identify stream discharge components, biogeochemical processes involved in nutrient cycling (such as N and P dynamics), nutrient sources and transport to rivers, and subsurface storage zones and residence times of hyporheic water. Several studies which have employed isotope techniques to clarify the processes occurring when groundwater enters the river,are reported in this chapter, with a view to highlighting both the advantages and limitations of these

Integrating Fuzzy Logic, Optimization, and GIS for Ecological Impact Assessments

Science.gov (United States)

Bojórquez-Tapia, Luis A.; Juárez, Lourdes; Cruz-Bello, Gustavo

2002-09-01

Appraisal of ecological impacts has been problematic because of the behavior of ecological system and the responses of these systems to human intervention are far from fully understood. While it has been relatively easy to itemize the potential ecological impacts, it has been difficult to arrive at accurate predictions of how these impacts affect populations, communities, or ecosystems. Furthermore, the spatial heterogeneity of ecological systems has been overlooked because its examination is practically impossible through matrix techniques, the most commonly used impact assessment approach. Besides, the public has become increasingly aware of the importance of the EIA in decision-making and thus the interpretation of impact significance is complicated further by the different value judgments of stakeholders. Moreover, impact assessments are carried out with a minimum of data, high uncertainty, and poor conceptual understanding. Hence, the evaluation of ecological impacts entails the integration of subjective and often conflicting judgments from a variety of experts and stakeholders. The purpose of this paper is to present an environmental impact assessment approach based on the integration fuzzy logic, geographical information systems and optimization techniques. This approach enables environmental analysts to deal with the intrinsic imprecision and ambiguity associated with the judgments of experts and stakeholders, the description of ecological systems, and the prediction of ecological impacts. The application of this approach is illustrated through an example, which shows how consensus about impact mitigation can be attained within a conflict resolution framework.

An integrated conceptual framework for long-term social-ecological research

Science.gov (United States)

S.L. Collins; S.R. Carpenter; S.M. Swinton; D.E. Orenstein; D.L. Childers; T.L. Gragson; N.B. Grimm; J.M. Grove; S.L. Harlan; J.P. Kaye; A.K. Knapp; G.P. Kofinas; J.J. Magnuson; W.H. McDowell; J.M. Melack; L.A. Ogden; G.P. Robertson; M.D. Smith; A.C. Whitmer

2010-01-01

The global reach of human activities affects all natural ecosystems, so that the environment is best viewed as a social-ecological system. Consequently, a more integrative approach to environmental science, one that bridges the biophysical and social domains, is sorely needed. Although models and frameworks for social-ecological systems exist, few are explicitly...

Stable isotope views on ecosystem function: challenging or challenged?

Science.gov (United States)

Resco, Víctor; Querejeta, José I; Ogle, Kiona; Voltas, Jordi; Sebastià, Maria-Teresa; Serrano-Ortiz, Penélope; Linares, Juan C; Moreno-Gutiérrez, Cristina; Herrero, Asier; Carreira, José A; Torres-Cañabate, Patricia; Valladares, Fernando

2010-06-23

Stable isotopes and their potential for detecting various and complex ecosystem processes are attracting an increasing number of scientists. Progress is challenging, particularly under global change scenarios, but some established views have been challenged. The IX meeting of the Spanish Association of Terrestrial Ecology (AAET, Ubeda, 18-22 October 2009) hosted a symposium on the ecology of stable isotopes where the linear mixing model approach of partitioning sinks and sources of carbon and water fluxes within an ecosystem was challenged, and new applications of stable isotopes for the study of plant interactions were evaluated. Discussion was also centred on the need for networks that monitor ecological processes using stable isotopes and key ideas for fostering future research with isotopes.

Rivers are social–ecological systems: Time to integrate human dimensions into riverscape ecology and management

Science.gov (United States)

Dunham, Jason B.; Angermeier, Paul L.; Crausbay, Shelley D.; Cravens, Amanda; Gosnell, Hannah; McEvoy, Jamie; Moritz, Max A.; Raheem, Nejem; Sanford, Todd

2018-01-01

Incorporation of concepts from landscape ecology into understanding and managing riverine ecosystems has become widely known as riverscape ecology. Riverscape ecology emphasizes interactions among processes at different scales and their consequences for valued ecosystem components, such as riverine fishes. Past studies have focused strongly on understanding the ecological processes in riverscapes and how human actions modify those processes. It is increasingly clear, however, that an understanding of the drivers behind actions that lead to human modification also merit consideration, especially regarding how those drivers influence management efficacy. These indirect drivers of riverscape outcomes can be understood in the context of a diverse array of social processes, which we collectively refer to as human dimensions. Like ecological phenomena, social processes also exhibit complex interactions across spatiotemporal scales. Greater emphasis on feedbacks between social and ecological processes will lead scientists and managers to more completely understand riverscapes as complex, dynamic, interacting social–ecological systems. Emerging applications in riverscapes, as well as studies of other ecosystems, provide examples that can lead to stronger integration of social and ecological science. We argue that conservation successes within riverscapes may not come from better ecological science, improved ecosystem service analyses, or even economic incentives if the fundamental drivers of human behaviors are not understood and addressed in conservation planning and implementation.

Ecological assessment of integrated bioenergy systems using the Sustainable Process Index

International Nuclear Information System (INIS)

Krotscheck, C.; Konig, F.; Obernberger, I.

2000-01-01

Biomass utilisation for energy production presently faces an uphill battle against fossil fuels. The use of biomass must offer additional benefits to compensate for higher prices: on the basis of a life cycle assessment (using BEAM to evaluate a variety of integrated bioenergy systems in connection with the Sustainable Process Index as a highly aggregated environmental pressure index) it is shown that integrated bioenergy systems are superior to fossil fuel systems in terms of environmental compatibility. The implementation of sustainability measures provides additional valuable information that might help in constructing and optimising integrated bioenergy systems. For a set of reference processes, among them fast pyrolysis, atmospheric gasification, integrated gasification combined cycle (IGCC), combustion and steam cycle (CS) and conventional hydrolysis, a detailed impact assessment is shown. Sensitivity analyses of the most important ecological parameters are calculated, giving an overview of the impacts of various stages in the total life cycle and showing 'what really matters'. Much of the ecological impact of integrated bioenergy systems is induced by feedstock production. It is mainly the use of fossil fuels in cultivation, harvesting and transportation as well as the use of fertilisers in short-rotation coppice production that impose considerable ecological pressure. Concerning electricity generation the most problematic pressures are due to gaseous emissions, most notably the release of NO x . Moreover, a rather complicated process (high amount of grey energy) and the use of fossil pilot fuel (co-combustion) leads to a rather weak ecological performance in contrast to other 100% biomass-based systems. (author)

Integrated ecological-economic fisheries models - evaluation, review and challenges for implementation

DEFF Research Database (Denmark)

Nielsen, J. Rasmus; Thunberg, Eric; Holland, Daniel S.

2018-01-01

and comparative evaluation of 35 IESFM´s applied to marine fisheries and marine ecosystem resources to identify the characteristics that determine their usefulness, effectiveness and implementation. The focus is on fully integrated models that allow for feedbacks between ecological and human processes though......Marine ecosystems evolve under many interconnected and area-specific pressures. In order to fulfill society's intensifying and diversifying needs whilst ensuring ecologically sustainable development, more effective marine spatial planning and broader-scope management of marine resources...... is necessary. Integrated ecological–socioeconomic fisheries models (IESFM) of marine systems are nee¬ded to evaluate impacts and sustainability of potential management actions and understand, and anti¬ci¬pate ecological, economic, and social dynamics at a range of scales from local to national and regional...

Stable isotope views on ecosystem function: challenging or challenged?

Science.gov (United States)

Resco, Víctor; Querejeta, José I.; Ogle, Kiona; Voltas, Jordi; Sebastià, Maria-Teresa; Serrano-Ortiz, Penélope; Linares, Juan C.; Moreno-Gutiérrez, Cristina; Herrero, Asier; Carreira, José A.; Torres-Cañabate, Patricia; Valladares, Fernando

2010-01-01

Stable isotopes and their potential for detecting various and complex ecosystem processes are attracting an increasing number of scientists. Progress is challenging, particularly under global change scenarios, but some established views have been challenged. The IX meeting of the Spanish Association of Terrestrial Ecology (AAET, Úbeda, 18–22 October 2009) hosted a symposium on the ecology of stable isotopes where the linear mixing model approach of partitioning sinks and sources of carbon and water fluxes within an ecosystem was challenged, and new applications of stable isotopes for the study of plant interactions were evaluated. Discussion was also centred on the need for networks that monitor ecological processes using stable isotopes and key ideas for fostering future research with isotopes. PMID:20015858

INTEGRATION OF AN ECONOMIC WITH AN ECOLOGICAL MODEL

Science.gov (United States)

We summarize our work on integration of an economy under imperfect competition with a simple Lotka-Volterra type ecological model. Firms and households operate within a single period planning horizon, thus there is no savings or investment. Wages are set by a dominant employer. P...

Stable Isotopic Insights into the Foraging Ecology of an Endangered Marine Predator, the Hawaiian Petrel

Science.gov (United States)

Wiley, A. E.; Ostrom, P. H.; James, H. F.

2010-12-01

Seabirds play vital roles in their ecosystems, both as predators in their oceanic foraging grounds and conduits of marine nutrients to island nesting sites. Despite growing evidence that food availability limits seabird populations, characterization of the diet and even foraging locations of some seabird species remains elusive. Here, we use stable carbon (δ13C) and nitrogen (δ15N) isotopes to study the foraging ecology of an endangered and poorly known seabird, the Hawaiian petrel (Pterodroma sandwichensis). This species nests solely on the main Hawaiian Islands but forages widely across the NE Pacific, sometimes traveling over 10,000km on single foraging trips. δ13C and δ15N values vary with trophic level and at the base of food webs throughout the marine range of the Hawaiian petrel. Thus, we are able to use isotope signatures in modern and ancient petrel tissues to track spatial and temporal variation in foraging location and diet. We find strong evidence of foraging segregation between populations, with hatch-year birds from the island of Hawaii exhibiting feather δ15N and δ13C values over 3‰ and 1 ‰ higher, respectively, than those found in Maui and Kauai hatch-year birds. There is also significant variation in δ15N values between feathers from Kauai, Hawaii, and Maui adults, indicating additional foraging segregation during the winter molt. To distinguish between the effects of trophic level and foraging location, we relate our data to those from seabirds with known diet and foraging location, as well as to previous characterizations of isoscapes in the NE Pacific and at-sea observations of our study species. Finally, we track Hawaiian petrel foraging ecology back in time through examination of stable isotope values in historical feathers and ancient bone collagen. We find that, despite a species-wide decline in δ15N values (consistent with trophic level decline), populations have maintained divergent isotopic niches through at least the past 1

The Metacity: A Conceptual Framework for Integrating Ecology and Urban Design

Directory of Open Access Journals (Sweden)

S. T. A. Pickett

2011-10-01

Full Text Available We introduce the term metacity as a conceptual framework that can be shared by ecologists and designers and applied across the wide variety of urban habitats found around the world. While the term metacity was introduced by UN-HABITAT to designate hyper cities of over twenty million people, for us it is not limited to large urban agglomerations, but rather refers to the proliferation of new forms of urbanization, each with distinct ecological and social attributes. These various urban configurations when combined with new digital sensing, communication and social networking technologies constitute a virtual meta-infrastructure, present in all cities today. This new metacity has the potential to integrate new activist forms of ecological and urban design research and practice in making the transition from sanitary to sustainable city models globally. The city of Baltimore, Maryland will be used both as a site to illustrate these recent urban trends, and also as an example of the integration of ecology and urban design pursued by the two authors over the past seven years [1,2]. Metacity theory is drawn from both an architectural analysis of contemporary forms of urbanism, new forms of digital monitoring and communication technologies, as well as metapopulation and metacommunity theories in ecology. We seek to provide tools and lessons from our experiences for realizing an integrated metacity approach to achieving social sustainability and ecological resilience on an increasingly urbanized planet.

Winter diets of immature green turtles (Chelonia mydas) on a northern feeding ground: integrating stomach contents and stable isotope analyses

Science.gov (United States)

Williams, Natalie C.; Bjorndal, Karen A.; Lamont, Margaret M.; Carthy, Raymond R.

2015-01-01

The foraging ecology and diet of the green turtle, Chelonia mydas, remain understudied, particularly in peripheral areas of its distribution. We assessed the diet of an aggregation of juvenile green turtles at the northern edge of its range during winter months using two approaches. Stomach content analyses provide a single time sample, and stable isotope analyses integrate diet over a several-month period. We evaluated diet consistency in prey choice over time by comparing the results of these two approaches. We examined stomach contents from 43 juvenile green turtles that died during cold stunning events in St. Joseph Bay, Florida, in 2008 and 2011. Stomach contents were evaluated for volume, dry mass, percent frequency of occurrence, and index of relative importance of individual diet items. Juvenile green turtles were omnivorous, feeding primarily on seagrasses and tunicates. Diet characterizations from stomach contents differed from those based on stable isotope analyses, indicating the turtles are not feeding consistently during winter months. Evaluation of diets during warm months is needed.

Dietary ecology of human

International Nuclear Information System (INIS)

Minagawa, Masao

1990-01-01

The dietary life of humans varies with the environment where they live and has been changing with time. It has become possible to examine such changes by using stable carbon and nitrogen isotope composition as a chemical tool. The present report outlines recent developments in the application of this tool and compares the dietary ecologies of various human groups from the viewpoint of isotope geochemistry. The history of the application of this tool to dietary analysis is summarized first, and features of the carbon and nitrogen isotope composition in animals and their relations with the food chain are outlined. The dietary ecology of the current people is then discussed in relation to the isotope composition in food, the isotope composition in hair of the current people, and determination of food habit of specific groups of people from such isotope compositions. For prediction of dietary composition, the report presents a flow chart for an algorism which is based on the Monte Carlo method. It also outlines processes for analyzing food habits of people in the prehistoric age, focusing on distribution of isotope composition in humans over the world. (N.K.)

A multimetric approach for predicting the ecological integrity of New Zealand streams

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Clapcott J.E.

2014-01-01

Full Text Available Integrating multiple measures of stream health into a combined metric can provide a holistic assessment of the ecological integrity of a stream. The aim of this study was to develop a multimetric index (MMI of stream integrity based on predictive modelling of national data sets of water quality, macroinvertebrates, fish and ecosystem process metrics. We used a boosted regression tree approach to calculate an observed/expected score for each metric prior to combining metrics in a MMI based on data availability and the strength of predictive models. The resulting MMI provides a geographically meaningful prediction of the ecological integrity of rivers in New Zealand, but identifies limitations in data and approach, providing focus for ongoing research.

Formative Assessment Design for PDA Integrated Ecology Observation

Science.gov (United States)

Hung, Pi-Hsia; Lin, Yu-Fen; Hwang, Gwo-Jen

2010-01-01

Ubiquitous computing and mobile technologies provide a new perspective for designing innovative outdoor learning experiences. The purpose of this study is to propose a formative assessment design for integrating PDAs into ecology observations. Three learning activities were conducted in this study. An action research approach was applied to…

The movement ecology of the straw-colored fruit bat, Eidolon helvum, in sub-Saharan Africa assessed by stable isotope ratios.

Directory of Open Access Journals (Sweden)

Gonzalo Ossa

Full Text Available Flying foxes (Pteropodidae are key seed dispersers on the African continent, yet their migratory behavior is largely unknown. Here, we studied the movement ecology of the straw-colored fruit bat, Eidolon helvum, and other fruit bats by analyzing stable isotope ratios in fur collected from museum specimens. In a triple-isotope approach based on samples of two ecologically similar non-migratory pteropodids, we first confirmed that a stable isotope approach is capable of delineating between geographically distinct locations in Sub-Saharan Africa. A discriminant function analysis assigned 84% of individuals correctly to their capture site. Further, we assessed how well hydrogen stable isotope ratios (δ(2H of fur keratin collected from non-migratory species (n = 191 individuals records variation in δ(2H of precipitation water in sub-Saharan Africa. Overall, we found positive, negative and no correlations within the six studied species. We then developed a reduced major axis regression equation based on individual data of non-migratory species to predict where potentially migratory E. helvum (n = 88 would come from based on their keratin δ(2H. Across non-migratory species, δ(2H of keratin and local water correlated positively. Based on the isoscape origin model, 22% of E. helvum were migratory, i.e. individuals had migrated over at least 250 km prior to their capture. Migratory individuals came from locations at a median distance of about 860 km from the collection site, four even from distances of at least 2,000 km. Ground-truthing of our isoscape origin model based on keratin δ(2H of extant E. helvum (n = 76 supported a high predictive power of assigning the provenance of African flying foxes. Our study highlights that stable isotope ratios can be used to explain the migratory behavior of flying foxes, even on the isotopically relatively homogenous African continent, and with material collected by museums many decades or more than a century ago.

The movement ecology of the straw-colored fruit bat, Eidolon helvum, in sub-Saharan Africa assessed by stable isotope ratios.

Science.gov (United States)

Ossa, Gonzalo; Kramer-Schadt, Stephanie; Peel, Alison J; Scharf, Anne K; Voigt, Christian C

2012-01-01

Flying foxes (Pteropodidae) are key seed dispersers on the African continent, yet their migratory behavior is largely unknown. Here, we studied the movement ecology of the straw-colored fruit bat, Eidolon helvum, and other fruit bats by analyzing stable isotope ratios in fur collected from museum specimens. In a triple-isotope approach based on samples of two ecologically similar non-migratory pteropodids, we first confirmed that a stable isotope approach is capable of delineating between geographically distinct locations in Sub-Saharan Africa. A discriminant function analysis assigned 84% of individuals correctly to their capture site. Further, we assessed how well hydrogen stable isotope ratios (δ(2)H) of fur keratin collected from non-migratory species (n = 191 individuals) records variation in δ(2)H of precipitation water in sub-Saharan Africa. Overall, we found positive, negative and no correlations within the six studied species. We then developed a reduced major axis regression equation based on individual data of non-migratory species to predict where potentially migratory E. helvum (n = 88) would come from based on their keratin δ(2)H. Across non-migratory species, δ(2)H of keratin and local water correlated positively. Based on the isoscape origin model, 22% of E. helvum were migratory, i.e. individuals had migrated over at least 250 km prior to their capture. Migratory individuals came from locations at a median distance of about 860 km from the collection site, four even from distances of at least 2,000 km. Ground-truthing of our isoscape origin model based on keratin δ(2)H of extant E. helvum (n = 76) supported a high predictive power of assigning the provenance of African flying foxes. Our study highlights that stable isotope ratios can be used to explain the migratory behavior of flying foxes, even on the isotopically relatively homogenous African continent, and with material collected by museums many decades or more than a century ago.

Missing ecology: integrating ecological perspectives with the social-ecological system framework

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Graham Epstein

2013-08-01

Full Text Available The social-ecological systems framework was designed to provide a common research tool for interdisciplinary investigations of social-ecological systems. However, its origin in institutional studies of the commons belies its interdisciplinary ambitions and highlights its relatively limited attention to ecology and natural scientific knowledge. This paper considers the biophysical components of the framework and its epistemological foundations as it relates to the incorporation of knowledge from the natural sciences. It finds that the mixture of inductive and deductive reasoning associated with socially-oriented investigations of these systems is lacking on the ecological side, which relies upon induction alone. As a result the paper proposes the addition of a seventh core sub-system to the social-ecological systems framework, ecological rules, which would allow scholars to explicitly incorporate knowledge from the natural sciences for deductive reasoning. The paper shows, through an instructive case study, how the addition of ecological rules can provide a more nuanced description of the factors that contribute to outcomes in social-ecological systems.

Integrating Ecological and Social Knowledge: Learning from CHANS Research

Directory of Open Access Journals (Sweden)

Bruce Shindler

2017-03-01

Full Text Available Scientists are increasingly called upon to integrate across ecological and social disciplines to tackle complex coupled human and natural system (CHANS problems. Integration of these disciplines is challenging and many scientists do not have experience with large integrated research projects. However, much can be learned about the complicated process of integration from such efforts. We document some of these lessons from a National Science Foundation-funded CHANS project (Forests, People, Fire and present considerations for developing and engaging in coupled human and natural system projects. Certainly we are not the first to undertake this endeavor, and many of our findings complement those of other research teams. We focus here on the process of coming together, learning to work as an integrated science team, and describe the challenges and opportunities of engaging stakeholders (agency personnel and citizen communities of interests in our efforts. Throughout this project our intention was to foster dialogue among diverse interests and, thus, incorporate this knowledge into uncovering primary social and ecological drivers of change. A primary tool was an agent-based model, Envision, that used this information in landscape simulation, visualization models, and scenario development. Although integration can be an end in itself, the proof of value in the approach can be the degree to which it provides new insights or tools to CHANS, including closer interaction among multiple stakeholders, that could not have been reached without it.

Organic and Isotopic Signatures of Life: Lessons from the Early Earth

Science.gov (United States)

Freeman, K. H.; Eigenbrode, J. L.; House, C. H.

2002-12-01

In the study of life on earth, isotopic analyses of organic biomarkers provide essential insight to their biological and environmental provenance. Isotopic analyses of organic materials on other planets present a number of challenges, both analytical and interpretive. Prebiotic planetary organic materials can derive from condensation reactions and by delivery through meteorites or interplanetary dust, with the relative importance of each influenced by the oxidation state of the atmosphere. Material delivered to planets can have an interstellar origin, although it is dominated by compounds influenced by the formation of the solar system. Each of these processes impact molecular isotopic signatures and must be considered in life-detection strategies. Pronounced effects are observed for hydrogen isotopes, with smaller fractionations observed for other elements. Theoretical, laboratory and observational studies of non-terrean materials are essential to further understand molecular isotopic heterogeneity associated with these exclusively abiotic processes. Studies of Archean-aged samples provide an important resource for interpreting molecular isotopic patterns as signatures of life processes. Carbon assimilation and biomass synthesis from simple precursor compounds typically discriminate against 13C. This generality, however, is complicated by the observations of a wide range of fractionation factors associated with important microbial carbon-uptake processes. Metabolic processes further distribute isotopic signatures, such that wide isotopic heterogeneity is observed among cellular biochemical constituents. In addition, preservation/contamination concerns dominate studies of very ancient organic matter, as they likely will in life-detection studies. However, both biochemical heterogeneity and sample integrity can be addressed by considering patterns from different paleoenvironments. Molecular results demonstrate that Late Archean microbial life on this planet was

Integrating technologies for scalable ecology and conservation

OpenAIRE

David C. Marvin; Lian Pin Koh; Antony J. Lynam; Serge Wich; Andrew B. Davies; Ramesh Krishnamurthy; Emma Stokes; Ruth Starkey; Gregory P. Asner

2016-01-01

Integration of multiple technologies greatly increases the spatial and temporal scales over which ecological patterns and processes can be studied, and threats to protected ecosystems can be identified and mitigated. A range of technology options relevant to ecologists and conservation practitioners are described, including ways they can be linked to increase the dimensionality of data collection efforts. Remote sensing, ground-based, and data fusion technologies are broadly discussed in the ...

Loop containment (joint integrity) assessment Brayton Isotope Power System flight system

International Nuclear Information System (INIS)

1976-01-01

The Brayton Isotope Power System (BIPS) contains a large number of joints. Since the failure of a joint would result in loss of the working fluid and consequential failure of the BIPS, the integrity of the joints is of paramount importance. The reliability of the ERDA BIPS loop containment (joint integrity) is evaluated. The conceptual flight system as presently configured is depicted. A brief description of the flight system is given

Seed isotopic analysis as a tool to understand ecological processes influencing plant development and physiology: the case study of Quercus rotundifolia Lam. in a desertification gradient in Mediterranean areas

Science.gov (United States)

Oliveira, Tatiana; Silva, Anabela; Rodrigues, Carla; Antunes Antunes, Cristina; Pinho, Pedro; Ramos, Alzira; João Pereira, Maria; Branquinho, Cristina; Máguas, Cristina

2014-05-01

Plant responses to climate change highly depend on the temporal variability in precipitation events and on plant specific strategies, such as drought tolerance and resilience. Within the different plant organs, seeds have become an important research tool in the past years to study plant development and nutrients allocation. Key features of seeds such as the tendency to accumulate and store nutrient compounds open many possibilities to explore isotope analysis (13C, 15N and 18O), with many outcomes in fields from ecology to food traceability. The application of light stable isotopes to plant materials have been used to study both physiological (i.e. photosynthesis and stomatal conductance), nutrients uptake and metabolism (origin of nitrogen and symbiotic associations) as well as many ecological processes, which will produce a distinctive isotope fingerprint on the plant tissues. Thus, the isotopic composition of certain bio and geo-elements of seeds, yielding relevant information on plant ecophysiology, are able to relate the plant functioning with local climatic conditions (e.g., temperature and precipitation). The application of isotope analysis in this way can be used as a proxy to understand complex environmental degradation processes such as land degradation in drylands resulting from various factors including climatic variations and human activities. In this study acorns of Quercus ilex plants were sampled during 2012-2013 in a region of southern Portugal, according to (i) soil land-use; (ii) aridity and desertification indexes. The approach developed combined plant seed analysis (seed morphology and compounds quantification) with isotope ratio mass spectrometry (δ13C, δ15N and δ18O) as a "tool" to study changes in plant ecophysiology over time and space. Seeds allow studies at specific temporal scale (development period) which varies according to its biology and depends on the climatic conditions where the plant is grown (i.e, seed's biomass integrate

Combining functional weed ecology and crop stable isotope ratios to identify cultivation intensity: a comparison of cereal production regimes in Haute Provence, France and Asturias, Spain.

Science.gov (United States)

Bogaard, Amy; Hodgson, John; Nitsch, Erika; Jones, Glynis; Styring, Amy; Diffey, Charlotte; Pouncett, John; Herbig, Christoph; Charles, Michael; Ertuğ, Füsun; Tugay, Osman; Filipovic, Dragana; Fraser, Rebecca

This investigation combines two independent methods of identifying crop growing conditions and husbandry practices-functional weed ecology and crop stable carbon and nitrogen isotope analysis-in order to assess their potential for inferring the intensity of past cereal production systems using archaeobotanical assemblages. Present-day organic cereal farming in Haute Provence, France features crop varieties adapted to low-nutrient soils managed through crop rotation, with little to no manuring. Weed quadrat survey of 60 crop field transects in this region revealed that floristic variation primarily reflects geographical differences. Functional ecological weed data clearly distinguish the Provence fields from those surveyed in a previous study of intensively managed spelt wheat in Asturias, north-western Spain: as expected, weed ecological data reflect higher soil fertility and disturbance in Asturias. Similarly, crop stable nitrogen isotope values distinguish between intensive manuring in Asturias and long-term cultivation with minimal manuring in Haute Provence. The new model of cereal cultivation intensity based on weed ecology and crop isotope values in Haute Provence and Asturias was tested through application to two other present-day regimes, successfully identifying a high-intensity regime in the Sighisoara region, Romania, and low-intensity production in Kastamonu, Turkey. Application of this new model to Neolithic archaeobotanical assemblages in central Europe suggests that early farming tended to be intensive, and likely incorporated manuring, but also exhibited considerable variation, providing a finer grained understanding of cultivation intensity than previously available.

Approaches for integrated assessment of ecological and eutrophication status of surface waters in Nordic Countries

DEFF Research Database (Denmark)

Andersen, Jesper H.; Aroviita, Jukka; Carstensen, Jacob

2016-01-01

We review approaches and tools currently used in Nordic countries (Denmark, Finland, Norway and Sweden) for integrated assessment of ‘ecological status’ sensu the EU Water Framework Directive as well as assessment of ‘eutrophication status’ in coastal and marine waters. Integration principles for...... principles applied within BQEs are critical and in need of harmonisation if we want a better understanding of potential transition in ecological status between surface water types, e.g. when riverine water enters a downstream lake or coastal water body.......We review approaches and tools currently used in Nordic countries (Denmark, Finland, Norway and Sweden) for integrated assessment of ‘ecological status’ sensu the EU Water Framework Directive as well as assessment of ‘eutrophication status’ in coastal and marine waters. Integration principles...

Bioassessment of the ecological integrity of river ecosystems using ...

African Journals Online (AJOL)

Bioassessment of the ecological integrity of river ecosystems using aquatic macroinvertebrates: an overview with a focus on South Africa. ... In conclusion, a number of potential avenues for further research regarding the use of macroinvertebrates in the bioassessment of river ecosystems are identified. Keywords: benthic ...

Shifts in rotifer life history in response to stable isotope enrichment: testing theories of isotope effects on organismal growth

Science.gov (United States)

2017-01-01

In ecology, stable isotope labelling is commonly used for tracing material transfer in trophic interactions, nutrient budgets and biogeochemical processes. The main assumption in this approach is that the enrichment with a heavy isotope has no effect on the organism growth and metabolism. This assumption is, however, challenged by theoretical considerations and experimental studies on kinetic isotope effects in vivo. Here, I demonstrate profound changes in life histories of the rotifer Brachionus plicatilis fed 15N-enriched algae (0.4–5.0 at%); i.e. at the enrichment levels commonly used in ecological studies. These findings support theoretically predicted effects of heavy isotope enrichment on growth, metabolism and ageing in biological systems and underline the importance of accounting for such effects when using stable isotope labelling in experimental studies. PMID:28405367

Monitoring Ecological Resources within U.S. National Parks: Developing "Vital Signs" of Ecological Integrity for the Northeast Temperate Network

Science.gov (United States)

Don Faber-Langendoen; Geraldine Tierney; James Gibbs; Greg Shriver; Fred Dieffenbach; Pam Lombard

2006-01-01

The National Park Service (NPS) initiated a new “Vital Signs” program in 1998 to develop comprehensive, long-term monitoring of ecological resources within U.S. national parks. Vital signs (VS) are indicators, and are defined as key elements, processes or features of the environment that can be measured or estimated and that indicate the ecological integrity of an...

Application of stable isotope analysis to study temporal changes in foraging ecology in a highly endangered amphibian.

Directory of Open Access Journals (Sweden)

J Hayley Gillespie

Full Text Available Understanding dietary trends for endangered species may be essential to assessing the effects of ecological disturbances such as habitat modification, species introductions or global climate change. Documenting temporal variation in prey selection may also be crucial for understanding population dynamics. However, the rarity, secretive behaviours and obscure microhabitats of some endangered species can make direct foraging observations difficult or impossible. Furthermore, the lethality or invasiveness of some traditional methods of dietary analysis (e.g. gut contents analysis, gastric lavage makes them inappropriate for such species. Stable isotope analysis facilitates non-lethal, indirect analysis of animal diet that has unrealized potential in the conservation of endangered organisms, particularly amphibians.I determined proportional contributions of aquatic macroinvertebrate prey to the diet of an endangered aquatic salamander Eurycea sosorum over a two-year period using stable isotope analysis of (13/12C and (15/14N and the Bayesian stable isotope mixing model SIAR. I calculated Strauss' dietary electivity indices by comparing these proportions with changing relative abundance of potential prey species through time. Stable isotope analyses revealed that a previously unknown prey item (soft-bodied planarian flatworms in the genus Dugesia made up the majority of E. sosorum diet. Results also demonstrate that E. sosorum is an opportunistic forager capable of diet switching to include a greater proportion of alternative prey when Dugesia populations decline. There is also evidence of intra-population dietary variation.Effective application of stable isotope analysis can help circumvent two key limitations commonly experienced by researchers of endangered species: the inability to directly observe these species in nature and the invasiveness or lethality of traditional methods of dietary analysis. This study illustrates the feasibility of stable

The Use of P isotope in the ecology and source environment research: A review

International Nuclear Information System (INIS)

Chu Qun; Feng Gu

2012-01-01

The use of tracers are widely to plant-soil-manue duction-environment systems which study activity of phosphorus, forms changes, utilization and changes. It induces the development of ecology and source environment. This review shows the approaches of tracer in plant-soil-manue duction-environment systems which include direct labeling technique, indirect labeling technique or exposed directly. The use of stable isotopes of oxygen in phosphate made it possible to quantify the phosphrous cycling under field conditions and water system. But it is limited in plant and soil systems. NMR techniques was widely used to study the changes of phosphorus forms. It supplies a new tools to quality and quantity of different forms of paraphos. (authors)

The use of P isotope in the ecology and source environment research: a review

International Nuclear Information System (INIS)

Chu Qun; Feng Gu

2011-01-01

The use of tracers are widely to plant-soi-manue duction-environment systems which study activity of phosphorus, forms changes, utilization and changes. It induces the development of ecology and sorce environment. This review shows the approache of tracer in plant-soi-manue duction-environment systems which include direct labeling technique, indirect labeling technique or exposed directly. The use of stable isotopes of oxygen in phosphate made it possible to quantify the phosphrus cycling under field canditions and aer system. But it is limited in plant and soil systems. NMR techniques was widely used to study the changes of phosphorus forms. It supplies a new tools to qanlity and quantity of diffrenct forms of phophrus. (authors)

Ancient feeding ecology inferred from stable isotopic evidence from fossil horses in South America over the past 3 Ma

Directory of Open Access Journals (Sweden)

Alberdi María T

2011-06-01

Full Text Available Abstract Background Stable isotope ratios (13C/12C and 18O/16O in fossil teeth and bone provide key archives for understanding the ecology of extinct horses during the Plio-Pleistocene in South America; however, what happened in areas of sympatry between Equus (Amerhippus and Hippidion is less understood. Results Here, we use stable carbon and oxygen isotopes preserved in 67 fossil tooth and bone samples for seven species of horses from 25 different localities to document the magnitude of the dietary shifts of horses and ancient floral change during the Plio-Pleistocene. Dietary reconstructions inferred from stable isotopes of both genera of horses present in South America document dietary separation and environmental changes in ancient ecosystems, including C3/C4 transitions. Stable isotope data demonstrate changes in C4 grass consumption, inter-species dietary partitioning and variation in isotopic niche breadth of mixed feeders with latitudinal gradient. Conclusions The data for Hippidion indicate a preference varying from C3 plants to mixed C3-C4 plants in their diet. Equus (Amerhippus shows three different patterns of dietary partitioning Equus (A. neogeus from the province of Buenos Aires indicate a preference for C3 plants in the diet. Equus (A. andium from Ecuador and Equus (A. insulatus from Bolivia show a preference for to a diet of mixed C3-C4 plants, while Equus (A. santaeelenae from La Carolina (sea level of Ecuador and Brazil are mostly C4 feeders. These results confirm that ancient feeding ecology cannot always be inferred from dental morphology. While the carbon isotope composition of horses skeletal material decreased as latitude increased, we found evidence of boundary between a mixed C3/C4 diet signal and a pure C4 signal around 32° S and a change from a mixed diet signal to an exclusively C3 signal around 35°S. We found that the horses living at high altitudes and at low to middle latitude still have a C4 component in their

How livestock and flooding mediate the ecological integrity of working forests in Amazon River floodplains.

Science.gov (United States)

Lucas, Christine M; Sheikh, Pervaze; Gagnon, Paul R; Mcgrath, David G

2016-01-01

The contribution of working forests to tropical conservation and development depends upon the maintenance of ecological integrity under ongoing land use. Assessment of ecological integrity requires an understanding of the structure, composition, and function and major drivers that govern their variability. Working forests in tropical river floodplains provide many goods and services, yet the data on the ecological processes that sustain these services is scant. In flooded forests of riverside Amazonian communities, we established 46 0.1-ha plots varying in flood duration, use by cattle and water buffalo, and time since agricultural abandonment (30-90 yr). We monitored three aspects of ecological integrity (stand structure, species composition, and dynamics of trees and seedlings) to evaluate the impacts of different trajectories of livestock activity (alleviation, stasis, and intensification) over nine years. Negative effects of livestock intensification were solely evident in the forest understory, and plots alleviated from past heavy disturbance increased in seedling density but had higher abundance of thorny species than plots maintaining low activity. Stand structure, dynamics, and tree species composition were strongly influenced by the natural pulse of seasonal floods, such that the defining characteristics of integrity were dependent upon flood duration (3-200 d). Forests with prolonged floods ≥ 140 d had not only lower species richness but also lower rates of recruitment and species turnover relative to forests with short floods flooding hindered forest regeneration, but overall forest integrity was largely related to the hydrological regime and age. Given this disjunction between factors mediating canopy and understory integrity, we present a subset of metrics for regeneration and recruitment to distinguish forest condition by livestock trajectory. Although our study design includes confounded factors that preclude a definitive assessment of the major

The Socio-ecological Fit of Human Responses to Environmental Degradation: An Integrated Assessment Methodology

Science.gov (United States)

Briassoulis, Helen

2015-12-01

The scientific and policy interest in the human responses to environmental degradation usually focuses on responses sensu stricto and `best practices' that potentially abate degradation in affected areas. The transfer of individual, discrete instruments and `best practices' to different contexts is challenging, however, because socio-ecological systems are complex and environmental degradation is contextual and contingent. To sensibly assess the effectiveness of formal and informal interventions to combat environmental degradation, the paper proposes an integrative, non-reductionist analytic, the `response assemblage', for the study of `responses-in-context,' i.e., products of human decisions to utilize environmental resources to satisfy human needs in socio-ecological systems. Response assemblages are defined as geographically and historically unique, provisional, open, territorial wholes, complex compositions emerging from processes of assembling biophysical and human components, including responses sensu stricto, from affected focal and other socio-ecological systems, to serve human goals, one of which may be combatting environmental degradation. The degree of match among the components, called the socio- ecological fit of the response assemblage, indicates how effectively their contextual and contingent interactions maintain the socio-ecological resilience, promote sustainable development, and secure the continuous provision of ecosystem services in a focal socio-ecological system. The paper presents a conceptual approach to the analysis of the socio-ecological fit of response assemblages and details an integrated assessment methodology synthesizing the resilience, assemblage, and `problem of fit' literature. Lastly, it summarizes the novelty, value, and policy relevance of conceptualizing human responses as response assemblages and of the integrated assessment methodology, reconsiders `best practices' and suggests selected future research directions.

Russian ElectroKhimPribor integrated plant - producer and supplier of enriched stable isotopes

International Nuclear Information System (INIS)

Tatarinov, A.N.; Polyakov, L.A.

1997-01-01

Russian ElectroKhimPribor Integrated Plant, as well as ORNL, is a leading production which manufactures and supplied to the world market such specific products as stable isotopes. More than 200 isotopes of 44 elements can be obtained at its electromagnetic separator. Changes being underway for a few last years in Russia affected production and distribution of stable isotopes. There arose a necessity in a new approach to handling work in this field so as to create favourable conditions for both producers and customers. As a result, positive changes in calutron operation at ElectroKhimPribor has been reached; quality management system covering all stages of production has been set up; large and attractive stock of isotopes has been created; prospective scientific isotope-based developments are taken into account when planning separation F campaigns; executing the contracts is guaranteed; business philosophy has been changed to meet maximum of customer needs. For more than forty years ElectroKhimPribor have had no claim from customers as to quality of products or implementing contracts. Supplying enriched stable isotopes virtually to all the world's leading customers, ElectroKhimPribor cooperates successfully with Canadian company Trace Science since 1996

Evolution in a Community Context: On Integrating Ecological Interactions and Macroevolution.

Science.gov (United States)

Weber, Marjorie G; Wagner, Catherine E; Best, Rebecca J; Harmon, Luke J; Matthews, Blake

2017-04-01

Despite a conceptual understanding that evolution and species interactions are inextricably linked, it remains challenging to study ecological and evolutionary dynamics together over long temporal scales. In this review, we argue that, despite inherent challenges associated with reconstructing historical processes, the interplay of ecology and evolution is central to our understanding of macroevolution and community coexistence, and cannot be safely ignored in community and comparative phylogenetic studies. We highlight new research avenues that foster greater consideration of both ecological and evolutionary dynamics as processes that occur along branches of phylogenetic trees. By promoting new ways forward using this perspective, we hope to inspire further integration that creatively co-utilizes phylogenies and ecological data to study eco-evolutionary dynamics over time and space. Copyright © 2017 Elsevier Ltd. All rights reserved.

Application of heavy stable isotopes in forensic isotope geochemistry: A review

International Nuclear Information System (INIS)

Aggarwal, Jugdeep; Habicht-Mauche, Judith; Juarez, Chelsey

2008-01-01

Light stable isotopes have been used for many years to characterize the source and transport of materials. More recently heavy isotope systems such as Sr, Nd and Pb have been added to this list in order to aid source identification. With the advent of multiple collector ICP-MS, the range of isotopic tools now available has increased considerably, however, until the isotope systematics of these new non-traditional isotope systems have become better understood, they will not be as useful in characterizing material source and transportation. Applications using heavy metal stable isotopes (mostly traditional heavy isotopes) have reached most avenues in science, including earth sciences, archaeology, anthropology, animal physiology, ecology and toxicology. This field will continue to grow as new applications are developed and techniques become simpler and quicker. This paper provides a review of how this field has grown and presents two new applications using Pb and Sr isotopes in glazes to determine the source of ore used in glazes, and using Sr isotopes to determine the origin of undocumented deceased Mexican border crossers

Application of heavy stable isotopes in forensic isotope geochemistry: A review

Energy Technology Data Exchange (ETDEWEB)

Aggarwal, Jugdeep [W.M. Keck Isotope Laboratory, Department of Earth Sciences, University of California, Santa Cruz, CA 95064 (United States)], E-mail: jaggarwal@pmc.ucsc.edu; Habicht-Mauche, Judith; Juarez, Chelsey [Department of Anthropology, University of California, Santa Cruz, CA 95064 (United States)

2008-09-15

Light stable isotopes have been used for many years to characterize the source and transport of materials. More recently heavy isotope systems such as Sr, Nd and Pb have been added to this list in order to aid source identification. With the advent of multiple collector ICP-MS, the range of isotopic tools now available has increased considerably, however, until the isotope systematics of these new non-traditional isotope systems have become better understood, they will not be as useful in characterizing material source and transportation. Applications using heavy metal stable isotopes (mostly traditional heavy isotopes) have reached most avenues in science, including earth sciences, archaeology, anthropology, animal physiology, ecology and toxicology. This field will continue to grow as new applications are developed and techniques become simpler and quicker. This paper provides a review of how this field has grown and presents two new applications using Pb and Sr isotopes in glazes to determine the source of ore used in glazes, and using Sr isotopes to determine the origin of undocumented deceased Mexican border crossers.

Integration of research infrastructures and ecosystem models toward development of predictive ecology

Science.gov (United States)

Luo, Y.; Huang, Y.; Jiang, J.; MA, S.; Saruta, V.; Liang, G.; Hanson, P. J.; Ricciuto, D. M.; Milcu, A.; Roy, J.

2017-12-01

The past two decades have witnessed rapid development in sensor technology. Built upon the sensor development, large research infrastructure facilities, such as National Ecological Observatory Network (NEON) and FLUXNET, have been established. Through networking different kinds of sensors and other data collections at many locations all over the world, those facilities generate large volumes of ecological data every day. The big data from those facilities offer an unprecedented opportunity for advancing our understanding of ecological processes, educating teachers and students, supporting decision-making, and testing ecological theory. The big data from the major research infrastructure facilities also provides foundation for developing predictive ecology. Indeed, the capability to predict future changes in our living environment and natural resources is critical to decision making in a world where the past is no longer a clear guide to the future. We are living in a period marked by rapid climate change, profound alteration of biogeochemical cycles, unsustainable depletion of natural resources, and deterioration of air and water quality. Projecting changes in future ecosystem services to the society becomes essential not only for science but also for policy making. We will use this panel format to outline major opportunities and challenges in integrating research infrastructure and ecosystem models toward developing predictive ecology. Meanwhile, we will also show results from an interactive model-experiment System - Ecological Platform for Assimilating Data into models (EcoPAD) - that have been implemented at the Spruce and Peatland Responses Under Climatic and Environmental change (SPRUCE) experiment in Northern Minnesota and Montpellier Ecotron, France. EcoPAD is developed by integrating web technology, eco-informatics, data assimilation techniques, and ecosystem modeling. EcoPAD is designed to streamline data transfer seamlessly from research infrastructure

Integral Indicator of Ecological Footprint for Croatian Power Plants

International Nuclear Information System (INIS)

Strijov, V.; Granic, G.; Juric, Z.; Jelavic, B.; Antesevic Maricic, S.

2009-01-01

The main goal of this paper is to present the methodology of construction of the Integral Indicator for Croatian Thermal Power Plants and Combined Heat and Power Plants. The Integral Indicator is necessary to compare Power Plants selected according to a certain criterion. The criterion of the Ecological Footprint is chosen. The following features of the Power Plants are used: generated electricity and heat; consumed coal and liquid fuel; sulphur content in fuel; emitted CO 2 , SO 2 , NO x and particles. To construct the Integral Indicator the linear model is used. The model parameters are tuned by the Principal Component Analysis algorithm. The constructed Integral Indicator is compared with several others, such as Pareto-Optimal Slicing Indicator and Metric Indicator. The Integral Indicator keeps as much information about features of the Power Plants as possible; it is simple and robust.(author).

Using Stable Isotope Analysis to Understand the Migration and Trophic Ecology of Northeastern Pacific White Sharks (Carcharodon carcharias)

Science.gov (United States)

Carlisle, Aaron B.; Kim, Sora L.; Semmens, Brice X.; Madigan, Daniel J.; Jorgensen, Salvador J.; Perle, Christopher R.; Anderson, Scot D.; Chapple, Taylor K.; Kanive, Paul E.; Block, Barbara A.

2012-01-01

The white shark (Carcharodon carcharias) is a wide-ranging apex predator in the northeastern Pacific (NEP). Electronic tagging has demonstrated that white sharks exhibit a regular migratory pattern, occurring at coastal sites during the late summer, autumn and early winter and moving offshore to oceanic habitats during the remainder of the year, although the purpose of these migrations remains unclear. The purpose of this study was to use stable isotope analysis (SIA) to provide insight into the trophic ecology and migratory behaviors of white sharks in the NEP. Between 2006 and 2009, 53 white sharks were biopsied in central California to obtain dermal and muscle tissues, which were analyzed for stable isotope values of carbon (δ13C) and nitrogen (δ15N). We developed a mixing model that directly incorporates movement data and tissue incorporation (turnover) rates to better estimate the relative importance of different focal areas to white shark diet and elucidate their migratory behavior. Mixing model results for muscle showed a relatively equal dietary contribution from coastal and offshore regions, indicating that white sharks forage in both areas. However, model results indicated that sharks foraged at a higher relative rate in coastal habitats. There was a negative relationship between shark length and muscle δ13C and δ15N values, which may indicate ontogenetic changes in habitat use related to onset of maturity. The isotopic composition of dermal tissue was consistent with a more rapid incorporation rate than muscle and may represent more recent foraging. Low offshore consumption rates suggest that it is unlikely that foraging is the primary purpose of the offshore migrations. These results demonstrate how SIA can provide insight into the trophic ecology and migratory behavior of marine predators, especially when coupled with electronic tagging data. PMID:22355313

The Socio-ecological Fit of Human Responses to Environmental Degradation: An Integrated Assessment Methodology.

Science.gov (United States)

Briassoulis, Helen

2015-12-01

The scientific and policy interest in the human responses to environmental degradation usually focuses on responses sensu stricto and 'best practices' that potentially abate degradation in affected areas. The transfer of individual, discrete instruments and 'best practices' to different contexts is challenging, however, because socio-ecological systems are complex and environmental degradation is contextual and contingent. To sensibly assess the effectiveness of formal and informal interventions to combat environmental degradation, the paper proposes an integrative, non-reductionist analytic, the 'response assemblage', for the study of 'responses-in-context,' i.e., products of human decisions to utilize environmental resources to satisfy human needs in socio-ecological systems. Response assemblages are defined as geographically and historically unique, provisional, open, territorial wholes, complex compositions emerging from processes of assembling biophysical and human components, including responses sensu stricto, from affected focal and other socio-ecological systems, to serve human goals, one of which may be combatting environmental degradation. The degree of match among the components, called the socio-ecological fit of the response assemblage, indicates how effectively their contextual and contingent interactions maintain the socio-ecological resilience, promote sustainable development, and secure the continuous provision of ecosystem services in a focal socio-ecological system. The paper presents a conceptual approach to the analysis of the socio-ecological fit of response assemblages and details an integrated assessment methodology synthesizing the resilience, assemblage, and 'problem of fit' literature. Lastly, it summarizes the novelty, value, and policy relevance of conceptualizing human responses as response assemblages and of the integrated assessment methodology, reconsiders 'best practices' and suggests selected future research directions.

Spatial and trophic preferences of jumbo squid Dosidicus gigas (D´Orbigny, 1835) in the central Gulf of California: ecological inferences using stable isotopes.

Science.gov (United States)

Trasviña-Carrillo, L D; Hernández-Herrera, A; Torres-Rojas, Y E; Galván-Magaña, F; Sánchez-González, A; Aguíñiga-García, S

2018-04-26

The jumbo squid Dosidicus gigas is a fishery resource of considerable economic and ecological importance in the Mexican Pacific. Studies on its habitat preferences are needed to understand recent fluctuations in the species' abundance and availability. Stable isotope analysis allows us to infer ecological aspects such as spatial distribution and trophic preferences. We used an isotope ratio mass spectrometer, automated for carbonate analysis, and coupled to an elemental analyzer, to determine the isotopic composition of statoliths (δ 18 O and δ 13 C values) and beaks (δ 13 C and δ 15 N values) from 219 individuals caught over two fishing seasons (2007 and 2009) off the coast of Santa Rosalía, in the central Gulf of California. We used these isotopic ratios to assess variation in spatial and trophic preferences by sex, size, and fishing season. In the 2009 group, we observed significant differences in statolith δ 13 C values and beak δ 13 C and δ 15 N values between males and females. Between size groups, we observed significant differences in statolith δ 18 O and δ 13 C values in 2007 and in beak δ 13 C and δ 15 N values during both seasons. Both seasons were characterized by high overlap in δ 18 O and δ 13 C values between sexes and in 2009 between size groups. We observed low trophic overlap between sexes in 2009 and between size groups during both seasons. The isotopic ratios from statoliths and beaks indicate that D. gigas has changed its spatial and trophic preferences, a shift that is probably related to changes in the species diet. This intraspecific variation in preferences could be related to characteristics such as size, which may influence squid distribution preferences. This article is protected by copyright. All rights reserved.

Determination of integrated neutron flux by the measurement of the isotopic ratios of cadmium and gadolinium

International Nuclear Information System (INIS)

Tomiyoshi, Irene Akemy

1982-01-01

In this work, the possibility of the indirect determination of the integrated neutron flux, through the change of isotopic ratios of cadmium and gadolinium was investigated. The samples of cadmium we/e gadolinium were irradiated in the IEA-Rl reactor. These elements were chosen because they have high thermal neutron absorption cross section which permit the change in the isotopic composition during a short irradiation time to be measured accurately. The isotopic ratios were measured with a thermionic mass spectrometer the silica-gel technique and arrangement with single filament were used for the cadmium analysis, where as the oxi - reduction technique and arrangement with double filaments were used for gadolinium analysis. The mass fractionation effects for cadmium and gadolinium were corrected respectively by the exponential and potential expansion of the isotopic fractionation factor per atomic mass unit. The flux values supplied by the Centro de Operacao e Utilizacao do Reator de Pesquisas do IPEN were extrapolated. These values and the integrated flux values obtained experimentally were compared. (author)

Integrating scientific, economic, and ecological aspects of global change

International Nuclear Information System (INIS)

Jacoby, H.D.; Yang, Z.

1994-01-01

The MIT Joint Program on the Science and Policy of Global Change is conducting research on methods for integrating the science of potential global change with economic analysis of litigation policies and quantification of economic and environmental impacts. The paper describes this work, with a focus on the way that research within the various contributing disciplines, and the design of their associated models, are influenced by the process of inclusion in an integrated framework for policy analysis. The results should contribute new insight into the relative importance of key feedbacks within the economy-climate-ecology system

An Integrated Approach to Explore the Relationship Among Economic, Construction Land Use, and Ecology Subsystems in Zhejiang Province, China

Directory of Open Access Journals (Sweden)

Chuyu Xia

2016-05-01

Full Text Available Zhejiang Province, China is experiencing rapid urbanization, facing the challenge of coupling socioeconomic development and ecological conservation. This paper establishes a comprehensive index system to assess coordinating development of economic, construction land use (CLU, and ecology subsystems. A Granger test and a coupling coordination model were applied to explore the causal relationship and the coordinated development state among the three subsystems from 2000 to 2012. The results showed that: (1 changes in the integrated value of the economic subsystem were the Granger cause of changes in the ecology and CLU subsystems, and the changes in the integrated values of ecology and CLU was each other’s Granger cause; (2 the coupling coordination relationship of the integrated value for economic–CLU–ecology was constrained by the relationship between the economic and the CLU subsystems from 2000 to 2004, and that between the ecology and the economic subsystems was the impediment of the sustainable development of economic–CLU–ecology from 2004 to 2012. This research helps to identify approach to sustainable development through analyzing synergistic effects, interdependencies, and trade-offs among the integrated economic–CLU–ecology values, and to make significant contribution to urban planning policies in rapid urbanization region.

'Ecological value added' in an integrated ecosystem-economy model. An indicator for sustainability

International Nuclear Information System (INIS)

Kratena, Kurt

2004-01-01

This paper sets up an input-output system of the relevant ecosystem flows that determine the carbon cycle in the global ecosystem. Introducing energy as the value added component in the ecosystem allows to calculate ecosystem prices expressed in 'energy values'. Linking the ecosystem with the economy in an integrated input-output model then allows to calculate prices of economic activities and of ecosystem activities. In analogy to the 'Ecological Footprint', where productive land is needed to absorb anthropogenic emissions, in this integrated input-output model additional carbon sinks are introduced for emission absorption. These carbon sinks need solar energy input, i.e. 'ecological value added'. Emission absorption as well as GDP therefore become activities valued in the numeraire of the integrated system, i.e.'energy values'. From that sustainability indicators can be derived

Dynamic heterogeneity: a framework to promote ecological integration and hypothesis generation in urban systems

Science.gov (United States)

S. T. A. Pickett; M. L. Cadenasso; E. J. Rosi-Marshall; Ken Belt; P. M. Groffman; Morgan Grove; E. G. Irwin; S. S. Kaushal; S. L. LaDeau; C. H. Nilon; C. M. Swan; P. S. Warren

2016-01-01

Urban areas are understood to be extraordinarily spatially heterogeneous. Spatial heterogeneity, and its causes, consequences, and changes, are central to ecological science. The social sciences and urban design and planning professions also include spatial heterogeneity as a key concern. However, urban ecology, as a pursuit that integrates across these disciplines,...

Stable isotopic variation in tropical forest plants for applications in primatology.

Science.gov (United States)

Blumenthal, Scott A; Rothman, Jessica M; Chritz, Kendra L; Cerling, Thure E

2016-10-01

Stable isotope analysis is a promising tool for investigating primate ecology although nuanced ecological applications remain challenging, in part due to the complex nature of isotopic variability in plant-animal systems. The aim of this study is to investigate sources of carbon and nitrogen isotopic variation at the base of primate food webs that reflect aspects of primate ecology. The majority of primates inhabit tropical forest ecosystems, which are dominated by C3 vegetation. We used stable isotope ratios in plants from Kibale National Park, Uganda, a well-studied closed-canopy tropical forest, to investigate sources of isotopic variation among C3 plants related to canopy stratification, leaf age, and plant part. Unpredictably, our results demonstrate that vertical stratification within the canopy does not explain carbon or nitrogen isotopic variation in leaves. Leaf age can be a significant source of isotopic variation, although the direction and magnitude of this difference is not consistent across tree species. Some plant parts are clearly differentiated in carbon and nitrogen isotopic composition, particularly leaves compared to non-photosynthetic parts such as reproductive parts and woody stem parts. Overall, variation in the isotopic composition of floral communities, plant species, and plant parts demonstrates that stable isotope studies must include analysis of local plant species and parts consumed by the primates under study from within the study area. Am. J. Primatol. 78:1041-1054, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

An integrated approach to isotopic study of crystalline rock for a high-level waste repository: Area phase

International Nuclear Information System (INIS)

Gilbert, L.A.

1986-01-01

An integrated approach to assessing isotopic systems in crystalline rock is planned for area phase studies. This approach combines radiogenic isotope systems with petrography in order to characterize potential crystalline repository media. The coeval use of selected isotope systems will minimize the limitations of each method and provide intensive parameters yielding data on alteration timing, secondary mineral formation, temperature history, and radionuclide species migration. Isotope systems will be selected in order to measure differences in sensitivity to thermal disturbances and mobility due to fluid interaction. Comparative evaluation of isotope pair behavior may be used in combination with mineral versus whole-rock dates to provide data on heating and mobilization of alkali elements, lanthanides, and gases, caused by future introduction of waste

Prioritizing Urban Habitats for Connectivity Conservation: Integrating Centrality and Ecological Metrics.

Science.gov (United States)

Poodat, Fatemeh; Arrowsmith, Colin; Fraser, David; Gordon, Ascelin

2015-09-01

Connectivity among fragmented areas of habitat has long been acknowledged as important for the viability of biological conservation, especially within highly modified landscapes. Identifying important habitat patches in ecological connectivity is a priority for many conservation strategies, and the application of 'graph theory' has been shown to provide useful information on connectivity. Despite the large number of metrics for connectivity derived from graph theory, only a small number have been compared in terms of the importance they assign to nodes in a network. This paper presents a study that aims to define a new set of metrics and compares these with traditional graph-based metrics, used in the prioritization of habitat patches for ecological connectivity. The metrics measured consist of "topological" metrics, "ecological metrics," and "integrated metrics," Integrated metrics are a combination of topological and ecological metrics. Eight metrics were applied to the habitat network for the fat-tailed dunnart within Greater Melbourne, Australia. A non-directional network was developed in which nodes were linked to adjacent nodes. These links were then weighted by the effective distance between patches. By applying each of the eight metrics for the study network, nodes were ranked according to their contribution to the overall network connectivity. The structured comparison revealed the similarity and differences in the way the habitat for the fat-tailed dunnart was ranked based on different classes of metrics. Due to the differences in the way the metrics operate, a suitable metric should be chosen that best meets the objectives established by the decision maker.

Iodine isotopes and radiation safety

International Nuclear Information System (INIS)

Styro, B.; Nedvekajte, T.; Filistovich, V.

1992-01-01

Methods of concentration determination of stable and radioactive iodine isotopes in the Earth's different geospheres are described. Iodine isotopes concentration data, chemical forms and transformations as well as their exchange among separate geospheres of their global biochemical circulation (ocean, atmosphere, lithosphere and biosphere) are presented. Information on iodine isotopes as after-effects of nuclear installations accident (in particular, the Chernobyl accident) is generalized. The book is intended for scientists and practical workers in ecology and radioactivity protection and for a students of physics. 442 refs.; 82 figs.; 36 tabs

Bomb-curve radiocarbon measurement of recent biologic tissues and applications to wildlife forensics and stable isotope (paleo)ecology

Science.gov (United States)

Uno, Kevin T.; Quade, Jay; Fisher, Daniel C.; Wittemyer, George; Douglas-Hamilton, Iain; Andanje, Samuel; Omondi, Patrick; Litoroh, Moses; Cerling, Thure E.

2013-07-01

Above-ground thermonuclear weapons testing from 1952 through 1962 nearly doubled the concentration of radiocarbon (14C) in the atmosphere. As a result, organic material formed during or after this period may be radiocarbon-dated using the abrupt rise and steady fall of the atmospheric 14C concentration known as the bomb-curve. We test the accuracy of accelerator mass spectrometry radiocarbon dating of 29 herbivore and plant tissues collected on known dates between 1905 and 2008 in East Africa. Herbivore samples include teeth, tusks, soft tissue, hair, and horn. Tissues formed after 1955 are dated to within 0.3-1.3 y of formation, depending on the tissue type, whereas tissues older than ca. 1955 have high age uncertainties (>17 y) due to the Suess effect. 14C dating of tissues has applications to stable isotope (paleo)ecology and wildlife forensics. We use data from 41 additional samples to determine growth rates of tusks, molars, and hair, which improve interpretations of serial stable isotope data for (paleo)ecological studies. 14C dating can also be used to calculate the time interval represented in periodic histological structures in dental tissues (i.e., perikymata), which in turn may be used as chronometers in fossil teeth. Bomb-curve 14C dating of confiscated animal tissues (e.g., ivory statues) can be used to determine whether trade of the item is legal, because many Convention of International Trade of Endangered Species restrictions are based on the age of the tissue, and thus can serve as a powerful forensic tool to combat illegal trade in animal parts.

An agro-ecological evaluation of aquaculture integration into farming systems of the Mekong Delta

NARCIS (Netherlands)

Phong, L.T.; Dam, van A.A.; Udo, H.M.J.; Mensvoort, van M.E.F.; Tri, L.Q.; Steenstra, F.A.; Zijpp, van der A.J.

2010-01-01

This study compared ecological sustainability of Integrated Agriculture-Aquaculture (IAA) systems with different forms and intensity of aquaculture integration in the Mekong Delta of Vietnam: orchard-based and low-input fish (O-LF); rice-based and medium-input fish (R-MF); and rice-based and

Integrating evo-devo with ecology for a better understanding of phenotypic evolution.

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Santos, M Emília; Berger, Chloé S; Refki, Peter N; Khila, Abderrahman

2015-11-01

Evolutionary developmental biology (evo-devo) has provided invaluable contributions to our understanding of the mechanistic relationship between genotypic and phenotypic change. Similarly, evolutionary ecology has greatly advanced our understanding of the relationship between the phenotype and the environment. To fully understand the evolution of organismal diversity, a thorough integration of these two fields is required. This integration remains highly challenging because model systems offering a rich ecological and evolutionary background, together with the availability of developmental genetic tools and genomic resources, are scarce. In this review, we introduce the semi-aquatic bugs (Gerromorpha, Heteroptera) as original models well suited to study why and how organisms diversify. The Gerromorpha invaded water surfaces over 200 mya and diversified into a range of remarkable new forms within this new ecological habitat. We summarize the biology and evolutionary history of this group of insects and highlight a set of characters associated with the habitat change and the diversification that followed. We further discuss the morphological, behavioral, molecular and genomic tools available that together make semi-aquatic bugs a prime model for integration across disciplines. We present case studies showing how the implementation and combination of these approaches can advance our understanding of how the interaction between genotypes, phenotypes and the environment drives the evolution of distinct morphologies. Finally, we explain how the same set of experimental designs can be applied in other systems to address similar biological questions. © The Author 2015. Published by Oxford University Press.

At the Nexus of History, Ecology, and Hydrobiogeochemistry: Improved Predictions across Scales through Integration.

Science.gov (United States)

Stegen, James C

2018-01-01

To improve predictions of ecosystem function in future environments, we need to integrate the ecological and environmental histories experienced by microbial communities with hydrobiogeochemistry across scales. A key issue is whether we can derive generalizable scaling relationships that describe this multiscale integration. There is a strong foundation for addressing these challenges. We have the ability to infer ecological history with null models and reveal impacts of environmental history through laboratory and field experimentation. Recent developments also provide opportunities to inform ecosystem models with targeted omics data. A major next step is coupling knowledge derived from such studies with multiscale modeling frameworks that are predictive under non-steady-state conditions. This is particularly true for systems spanning dynamic interfaces, which are often hot spots of hydrobiogeochemical function. We can advance predictive capabilities through a holistic perspective focused on the nexus of history, ecology, and hydrobiogeochemistry.

Integrating Ecological and Evolutionary Context in the Study of Maternal Stress.

Science.gov (United States)

Sheriff, Michael J; Bell, Alison; Boonstra, Rudy; Dantzer, Ben; Lavergne, Sophia G; McGhee, Katie E; MacLeod, Kirsty J; Winandy, Laurane; Zimmer, Cedric; Love, Oliver P

2017-09-01

Maternal stress can prenatally influence offspring phenotypes and there are an increasing number of ecological studies that are bringing to bear biomedical findings to natural systems. This is resulting in a shift from the perspective that maternal stress is unanimously costly, to one in which maternal stress may be beneficial to offspring. However, this adaptive perspective is in its infancy with much progress to still be made in understanding the role of maternal stress in natural systems. Our aim is to emphasize the importance of the ecological and evolutionary context within which adaptive hypotheses of maternal stress can be evaluated. We present five primary research areas where we think future research can make substantial progress: (1) understanding maternal and offspring control mechanisms that modulate exposure between maternal stress and subsequent offspring phenotype response; (2) understanding the dynamic nature of the interaction between mothers and their environment; (3) integrating offspring phenotypic responses and measuring both maternal and offspring fitness outcomes under real-life (either free-living or semi-natural) conditions; (4) empirically testing these fitness outcomes across relevant spatial and temporal environmental contexts (both pre- and post-natal environments); (5) examining the role of maternal stress effects in human-altered environments-i.e., do they limit or enhance fitness. To make progress, it is critical to understand the role of maternal stress in an ecological context and to do that, we must integrate across physiology, behavior, genetics, and evolution. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Trophic ecology influence on metal bioaccumulation in marine fish: Inference from stable isotope and fatty acid analyses.

Science.gov (United States)

Le Croizier, Gaël; Schaal, Gauthier; Gallon, Régis; Fall, Massal; Le Grand, Fabienne; Munaron, Jean-Marie; Rouget, Marie-Laure; Machu, Eric; Le Loc'h, François; Laë, Raymond; De Morais, Luis Tito

2016-12-15

The link between trophic ecology and metal accumulation in marine fish species was investigated through a multi-tracers approach combining fatty acid (FA) and stable isotope (SI) analyses on fish from two contrasted sites on the coast of Senegal, one subjected to anthropogenic metal effluents and another one less impacted. The concentrations of thirteen trace metal elements (As, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Sn, U, and Zn) were measured in fish liver. Individuals from each site were classified into three distinct groups according to their liver FA and muscle SI compositions. Trace element concentrations were tested between groups revealing that bioaccumulation of several metals was clearly dependent on the trophic guild of fish. Furthermore, correlations between individual trophic markers and trace metals gave new insights into the determination of their origin. Fatty acids revealed relationships between the dietary regimes and metal accumulation that were not detected with stable isotopes, possibly due to the trace metal elements analysed in this study. In the region exposed to metallic inputs, the consumption of benthic preys was the main pathway for metal transfer to the fish community while in the unaffected one, pelagic preys represented the main source of metals. Within pelagic sources, metallic transfer to fish depended on phytoplankton taxa on which the food web was based, suggesting that microphytoplankton (i.e., diatoms and dinoflagellates) were a more important source of exposition than nano- and picoplankton. This study confirmed the influence of diet in the metal accumulation of marine fish communities, and proved that FAs are very useful and complementary tools to SIs to link metal accumulation in fish with their trophic ecology. Copyright © 2016 Elsevier B.V. All rights reserved.

Toward a Theory of Integrated Urban Ecology: Complementing Pickett et al.

Directory of Open Access Journals (Sweden)

Robert Mugerauer

2010-12-01

Full Text Available The analyses substantially delineating "integrative studies of large urban areas as bio-physical-social complexes" and the suggestions by Pickett et al. in "Beyond Urban Legends" (Bioscience 2008 58 139-150 provide an initial framework for a theory of urban ecology. This article intends to contribute to the project by: 1 improving the philosophical rigor of critical concepts and epistemologies; 2 making explicit the complementary theoretical and empirical work in urban ecology already being done that can be better integrated, for example, studies from outside the U.S. and uses of actor network theory; 3 bringing forward more disciplines and theories which successfully deploy modes of thinking, research procedures, and practices more adequate to the phenomena at all scales and levels of particularity, i.e., micro, phenomenal, macro, to fill in some of the empirical gaps in the middle, specifically those having to do with human values and the richness of the everyday lifeworld. In addition to what is available within complexity theory itself, chief among the approaches to be utilized are phenomenology, ethnographic thick description, and actor network theory.

Bomb-curve radiocarbon measurement of recent biologic tissues and applications to wildlife forensics and stable isotope (paleo)ecology

Science.gov (United States)

Uno, Kevin T.; Quade, Jay; Fisher, Daniel C.; Wittemyer, George; Douglas-Hamilton, Iain; Andanje, Samuel; Omondi, Patrick; Litoroh, Moses; Cerling, Thure E.

2013-01-01

Above-ground thermonuclear weapons testing from 1952 through 1962 nearly doubled the concentration of radiocarbon (14C) in the atmosphere. As a result, organic material formed during or after this period may be radiocarbon-dated using the abrupt rise and steady fall of the atmospheric 14C concentration known as the bomb-curve. We test the accuracy of accelerator mass spectrometry radiocarbon dating of 29 herbivore and plant tissues collected on known dates between 1905 and 2008 in East Africa. Herbivore samples include teeth, tusks, soft tissue, hair, and horn. Tissues formed after 1955 are dated to within 0.3–1.3 y of formation, depending on the tissue type, whereas tissues older than ca. 1955 have high age uncertainties (>17 y) due to the Suess effect. 14C dating of tissues has applications to stable isotope (paleo)ecology and wildlife forensics. We use data from 41 additional samples to determine growth rates of tusks, molars, and hair, which improve interpretations of serial stable isotope data for (paleo)ecological studies. 14C dating can also be used to calculate the time interval represented in periodic histological structures in dental tissues (i.e., perikymata), which in turn may be used as chronometers in fossil teeth. Bomb-curve 14C dating of confiscated animal tissues (e.g., ivory statues) can be used to determine whether trade of the item is legal, because many Convention of International Trade of Endangered Species restrictions are based on the age of the tissue, and thus can serve as a powerful forensic tool to combat illegal trade in animal parts. PMID:23818577

Environmental management: Integrating ecological evaluation, remediation, restoration, natural resource damage assessment and long-term stewardship on contaminated lands

International Nuclear Information System (INIS)

Burger, Joanna

2008-01-01

Ecological evaluation is essential for remediation, restoration, and Natural Resource Damage Assessment (NRDA), and forms the basis for many management practices. These include determining status and trends of biological, physical, or chemical/radiological conditions, conducting environmental impact assessments, performing remedial actions should remediation fail, managing ecosystems and wildlife, and assessing the efficacy of remediation, restoration, and long-term stewardship. The objective of this paper is to explore the meanings of these assessments, examine the relationships among them, and suggest methods of integration that will move environmental management forward. While remediation, restoration, and NRDA, among others, are often conducted separately, it is important to integrate them for contaminated land where the risks to ecoreceptors (including humans) can be high, and the potential damage to functioning ecosystems great. Ecological evaluations can range from inventories of local plants and animals, determinations of reproductive success of particular species, levels of contaminants in organisms, kinds and levels of effects, and environmental impact assessments, to very formal ecological risk assessments for a chemical or other stressor. Such evaluations can range from the individual species to populations, communities, ecosystems or the landscape scale. Ecological evaluations serve as the basis for making decisions about the levels and kinds of remediation, the levels and kinds of restoration possible, and the degree and kinds of natural resource injuries that have occurred because of contamination. Many different disciplines are involved in ecological evaluation, including biologists, conservationists, foresters, restoration ecologists, ecological engineers, economists, hydrologist, and geologists. Since ecological evaluation forms the basis for so many different types of environmental management, it seems reasonable to integrate management options

Deforestation and climate feedbacks threaten the ecological integrity of south-southeastern Amazonia.

Science.gov (United States)

Coe, Michael T; Marthews, Toby R; Costa, Marcos Heil; Galbraith, David R; Greenglass, Nora L; Imbuzeiro, Hewlley M A; Levine, Naomi M; Malhi, Yadvinder; Moorcroft, Paul R; Muza, Michel Nobre; Powell, Thomas L; Saleska, Scott R; Solorzano, Luis A; Wang, Jingfeng

2013-06-05

A mosaic of protected areas, including indigenous lands, sustainable-use production forests and reserves and strictly protected forests is the cornerstone of conservation in the Amazon, with almost 50 per cent of the region now protected. However, recent research indicates that isolation from direct deforestation or degradation may not be sufficient to maintain the ecological integrity of Amazon forests over the next several decades. Large-scale changes in fire and drought regimes occurring as a result of deforestation and greenhouse gas increases may result in forest degradation, regardless of protected status. How severe or widespread these feedbacks will be is uncertain, but the arc of deforestation in south-southeastern Amazonia appears to be particularly vulnerable owing to high current deforestation rates and ecological sensitivity to climate change. Maintaining forest ecosystem integrity may require significant strengthening of forest conservation on private property, which can in part be accomplished by leveraging existing policy mechanisms.

Integrated safeguards and security for the INEL Special Isotope Separation Plant

International Nuclear Information System (INIS)

Warner, G.F.; Zack, N.R.

1990-01-01

This paper describes the development of the safeguards and security system that was to be used for the Special Isotope Separation (SIS) Production Plant. The US Department of Energy has postponed the construction of the SIS Plant that was to be built at the Idaho National Engineering Laboratory (INEL) site near Idaho Falls, Idaho. The Plant was designed to produce weapons grade plutonium from DOE owned fuel grade plutonium by converting off-spec. plutonium dioxide into metal buttons that would meet required chemical and isotopic specifications. Because this was to be a completely new facility there was a unique opportunity to provide an in-depth, ''state-of-the- art'' safeguards and security system without attempting to overlay upon an existing, older system. This facility was being designed to be in complete compliance with the new DOE Orders by integrating safeguards and security into the plant operating system and by providing graded protection to the areas of varying sensitivity within the plant

Territorial ordination and fragmentation of the landscape - Perspectives for the ecological integrity

International Nuclear Information System (INIS)

Velez Restrepo, Luis Anibal

2001-01-01

The field of planning increasingly emphasizes the importance of rooting the strategies of biological diversity on an ecological perspective of landscape linked to the processes and plans of structural reordering of the territory. However, there is still a conceptual and methodological tendency to go back to the old habits in many processes of land planning. This work discusses such disparity. It includes first a general discussion of traditional approaches to conservation and the new perspectives and concepts focused on landscape, second, examining the conventional ecological approach to planning and land use management it shows the fragmentary way in which it determines land uses without any attention to the workings of biodiversity. Finally, this paper looks at the importance and the opportunity of articulating spatial patterns and ecological processes in ways that maintain the integrity of landscape

Measurement of the Ecological Integrity of Cerrado Streams Using Biological Metrics and the Index of Habitat Integrity

Directory of Open Access Journals (Sweden)

Deusiano Florêncio dos Reis

2017-01-01

Full Text Available Generally, aquatic communities reflect the effects of anthropogenic changes such as deforestation or organic pollution. The Cerrado stands among the most threatened ecosystems by human activities in Brazil. In order to evaluate the ecological integrity of the streams in a preserved watershed in the Northern Cerrado biome corresponding to a mosaic of ecosystems in transition to the Amazonia biome in Brazil, biological metrics related to diversity, structure, and sensitivity of aquatic macroinvertebrates were calculated. Sampling included collections along stretches of 200 m of nine streams and measurements of abiotic variables (temperature, electrical conductivity, pH, total dissolved solids, dissolved oxygen, and discharge and the Index of Habitat Integrity (HII. The values of the abiotic variables and the HII indicated that most of the streams have good ecological integrity, due to high oxygen levels and low concentrations of dissolved solids and electric conductivity. Two streams showed altered HII scores mainly related to small dams for recreational and domestic use, use of Cerrado natural pasture for cattle raising, and spot deforestation in bathing areas. However, this finding is not reflected in the biological metrics that were used. Considering all nine streams, only two showed satisfactory ecological quality (measured by Biological Monitoring Working Party (BMWP, total richness, and EPT (Ephemeroptera, Plecoptera, and Trichoptera richness, only one of which had a low HII score. These results indicate that punctual measures of abiotic parameters do not reveal the long-term impacts of anthropic activities in these streams, including related fire management of pasture that annually alters the vegetation matrix and may act as a disturbance for the macroinvertebrate communities. Due to this, biomonitoring of low order streams in Cerrado ecosystems of the Northern Central Brazil by different biotic metrics and also physical attributes of the

The Steady State Great Ape? Long Term Isotopic Records Reveal the Effects of Season, Social Rank and Reproductive Status on Bonobo Feeding Behavior

Science.gov (United States)

Oelze, Vicky M.; Douglas, Pamela Heidi; Stephens, Colleen R.; Surbeck, Martin; Behringer, Verena; Richards, Michael P.; Fruth, Barbara; Hohmann, Gottfried

2016-01-01

Dietary ecology of extant great apes is known to respond to environmental conditions such as climate and food availability, but also to vary depending on social status and life history characteristics. Bonobos (Pan paniscus) live under comparatively steady ecological conditions in the evergreen rainforests of the Congo Basin. Bonobos are an ideal species for investigating influences of sociodemographic and physiological factors, such as female reproductive status, on diet. We investigate the long term dietary pattern in wild but fully habituated bonobos by stable isotope analysis in hair and integrating a variety of long-term sociodemographic information obtained through observations. We analyzed carbon and nitrogen stable isotopes in 432 hair sections obtained from 101 non-invasively collected hair samples. These samples represented the dietary behavior of 23 adult bonobos from 2008 through 2010. By including isotope and crude protein data from plants we could establish an isotope baseline and interpret the results of several general linear mixed models using the predictors climate, sex, social rank, reproductive state of females, adult age and age of infants. We found that low canopy foliage is a useful isotopic tracer for tropical rainforest settings, and consumption of terrestrial herbs best explains the temporal isotope patterns we found in carbon isotope values of bonobo hair. Only the diet of male bonobos was affected by social rank, with lower nitrogen isotope values in low-ranking young males. Female isotope values mainly differed between different stages of reproduction (cycling, pregnancy, lactation). These isotopic differences appear to be related to changes in dietary preference during pregnancy (high protein diet) and lactation (high energy diet), which allow to compensate for different nutritional needs during maternal investment. PMID:27626279

Manual for the Use of Stable Isotopes in Entomology

International Nuclear Information System (INIS)

2009-06-01

result of problem driven inquisitiveness and technological advances, and are framed by the social and political environment. Although the external environment may mould the technological path, a technology will only become obsolete if there are viable substitution products or methods. Stable isotope methods are a substitute for many radionuclide methods. The progress made in stable isotope science over the past twenty years is a direct result of the interplay of the above factors. Stable isotopes are omnipresent in the environment and pose no health or environmental risks. Advances in isotope ratio mass spectrometry in terms of detection, accuracy and automation have broadened experimental possibilities immensely over the past twenty years. It was recognised that there was significant potential for answering many of the entomologist?s biological and ecological questions using stable isotopes, an expertise the Soil Science Unit of the FAO/IAEA Agriculture and Biotechnology Laboratory in Seibersdorf had long fostered; therefore collaboration with the Entomology Unit at the same Laboratory was established. A number of collaborative experiments were carried and subsequently published. It was soon recognised that stable isotopes have tremendous potential in entomological research and although there were numerous studies using stable isotopes in ecology, their use in entomology per se was limited. Thus it was felt that a publication was required to make stable isotope techniques more widely known among entomologists. This manual will attempt to provide an introduction to the use of stable isotopes in entomological research. It will strive to communicate the basic principles and techniques of stable isotope science and provide a springboard for further interest and research in this area

A Sense of Place: Integrating Environmental Psychology into Marine Socio-Ecological Models

Science.gov (United States)

van Putten, I. E.; Fleming, A.; Fulton, E.; Plaganyi-Lloyd, E.

2016-02-01

Sense of place is a concept that is increasingly applied in different social research contexts where it can act as a bridge between disciplines that might otherwise work in parallel. A sense of place is a well established and flexible concept that has been empirically measured using different survey methods. The psychological principals and theories that underpin sense of place have been inextricably linked to the quality of ecological systems and the impact on development of the system, and vice versa. Ecological models and scenario analyses play an important role in characterising, assessing and predicting the potential impacts of alternative developments and other changes affecting ecological systems. To improve the predictive accuracy of ecological models, human drivers, interactions, and uses have been dynamically incorporated, for instance, through management strategy evaluation applied to marine ecosystem models. However, to date no socio-ecological models (whether terrestrial or marine) have been developed that incorporate a dynamic feedback between ecosystem characteristics and peoples' sense of place. These models thus essentially ignore the influence of environmental psychology on the way people use and interact with ecosystems. We develop a proof of concept and provide a mathematical basis for a Sense of Place Index (SoPI) that allows the quantitative integration of environmental psychology into socio-ecological models. Incorporating dynamic feedback between the SoPI for different resource user groups and the ecological system improves the accuracy and precision of predictions regarding future resource use as well as, ultimately, the potential state of the resource to be developed.

Realistic Fasting Does Not Affect Stable Isotope Levels of a Metabolically Efficient Salamander

Science.gov (United States)

Stable isotopes are commonly used to examine various aspects of animal ecology. The use of stable isotopes generally proceeds under the implicit assumption that resource use is the only factor driving variation in stable isotope levels; however, a wealth of studies demonstrate a...

Evaluation of the ecological integrity and ecosystem health of three benthic networks influenced by coastal upwelling in the northern Chile

Science.gov (United States)

The ecological health of ecosystems relates to the maintenance or restoration of optimal system function when confronted with a disturbance. A healthy ecosystem is a prerequisite for ecological sustainability. Ecological integrity has been defined as an emergent property of ecosy...

Integrating movement ecology with biodiversity research - exploring new avenues to address spatiotemporal biodiversity dynamics.

Science.gov (United States)

Jeltsch, Florian; Bonte, Dries; Pe'er, Guy; Reineking, Björn; Leimgruber, Peter; Balkenhol, Niko; Schröder, Boris; Buchmann, Carsten M; Mueller, Thomas; Blaum, Niels; Zurell, Damaris; Böhning-Gaese, Katrin; Wiegand, Thorsten; Eccard, Jana A; Hofer, Heribert; Reeg, Jette; Eggers, Ute; Bauer, Silke

2013-01-01

Movement of organisms is one of the key mechanisms shaping biodiversity, e.g. the distribution of genes, individuals and species in space and time. Recent technological and conceptual advances have improved our ability to assess the causes and consequences of individual movement, and led to the emergence of the new field of 'movement ecology'. Here, we outline how movement ecology can contribute to the broad field of biodiversity research, i.e. the study of processes and patterns of life among and across different scales, from genes to ecosystems, and we propose a conceptual framework linking these hitherto largely separated fields of research. Our framework builds on the concept of movement ecology for individuals, and demonstrates its importance for linking individual organismal movement with biodiversity. First, organismal movements can provide 'mobile links' between habitats or ecosystems, thereby connecting resources, genes, and processes among otherwise separate locations. Understanding these mobile links and their impact on biodiversity will be facilitated by movement ecology, because mobile links can be created by different modes of movement (i.e., foraging, dispersal, migration) that relate to different spatiotemporal scales and have differential effects on biodiversity. Second, organismal movements can also mediate coexistence in communities, through 'equalizing' and 'stabilizing' mechanisms. This novel integrated framework provides a conceptual starting point for a better understanding of biodiversity dynamics in light of individual movement and space-use behavior across spatiotemporal scales. By illustrating this framework with examples, we argue that the integration of movement ecology and biodiversity research will also enhance our ability to conserve diversity at the genetic, species, and ecosystem levels.

Integrative ecology: from molecules to ecosystems

National Research Council Canada - National Science Library

Woodward, G

2010-01-01

.... As such, none of these chapters are typical representatives of any single traditional field in ecology, as between them they attempt to forge new links from molecular biology to ecosystems ecology...

Integrated Ecological River Health Assessments, Based on Water Chemistry, Physical Habitat Quality and Biological Integrity

Directory of Open Access Journals (Sweden)

Ji Yoon Kim

2015-11-01

Full Text Available This study evaluated integrative river ecosystem health using stressor-based models of physical habitat health, chemical water health, and biological health of fish and identified multiple-stressor indicators influencing the ecosystem health. Integrated health responses (IHRs, based on star-plot approach, were calculated from qualitative habitat evaluation index (QHEI, nutrient pollution index (NPI, and index of biological integrity (IBI in four different longitudinal regions (Groups I–IV. For the calculations of IHRs values, multi-metric QHEI, NPI, and IBI models were developed and their criteria for the diagnosis of the health were determined. The longitudinal patterns of the river were analyzed by a self-organizing map (SOM model and the key major stressors in the river were identified by principal component analysis (PCA. Our model scores of integrated health responses (IHRs suggested that mid-stream and downstream regions were impaired, and the key stressors were closely associated with nutrient enrichment (N and P and organic matter pollutions from domestic wastewater disposal plants and urban sewage. This modeling approach of IHRs may be used as an effective tool for evaluations of integrative ecological river health..

From innovation to application: social-ecological context, diagnostics, drugs and integrated control of schistosomiasis.

Science.gov (United States)

Utzinger, Jürg; N'goran, Eliézer K; Caffrey, Conor R; Keiser, Jennifer

2011-09-01

Compared to malaria, tuberculosis and HIV/AIDS, schistosomiasis remains a truly neglected tropical disease. Schistosomiasis, perhaps more than any other disease, is entrenched in prevailing social-ecological systems, since transmission is governed by human behaviour (e.g. open defecation and patterns of unprotected surface water contacts) and ecological features (e.g. living in close proximity to suitable freshwater bodies in which intermediate host snails proliferate). Moreover, schistosomiasis is intimately linked with poverty and the disease has spread to previously non-endemic areas as a result of demographic, ecological and engineering transformations. Importantly though, thanks to increased advocacy there is growing awareness, financial and technical support to control and eventually eliminate schistosomiasis as a public health problem at local, regional and global scales. The purpose of this review is to highlight recent progress made in innovation, validation and application of new tools and strategies for research and integrated control of schistosomiasis. First, we explain that schistosomiasis is deeply embedded in social-ecological systems and explore linkages with poverty. We then summarize and challenge global statistics, risk maps and burden estimates of human schistosomiasis. Discovery and development research pertaining to novel diagnostics and drugs forms the centrepiece of our review. We discuss unresolved issues and emerging opportunities for integrated and sustainable control of schistosomiasis and conclude with a series of research needs. Copyright © 2010 Elsevier B.V. All rights reserved.

Integrated structural biology and molecular ecology of N-cycling enzymes from ammonia-oxidizing archaea.

Science.gov (United States)

Tolar, Bradley B; Herrmann, Jonathan; Bargar, John R; van den Bedem, Henry; Wakatsuki, Soichi; Francis, Christopher A

2017-10-01

Knowledge of the molecular ecology and environmental determinants of ammonia-oxidizing organisms is critical to understanding and predicting the global nitrogen (N) and carbon cycles, but an incomplete biochemical picture hinders in vitro studies of N-cycling enzymes. Although an integrative structural and dynamic characterization at the atomic scale would advance our understanding of function tremendously, structural knowledge of key N-cycling enzymes from ecologically relevant ammonia oxidizers is unfortunately extremely limited. Here, we discuss the challenges and opportunities for examining the ecology of ammonia-oxidizing organisms, particularly uncultivated Thaumarchaeota, through (meta)genome-driven structural biology of the enzymes ammonia monooxygenase (AMO) and nitrite reductase (NirK). © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

Integrating Future Land Use Scenarios to Evaluate the Spatio-Temporal Dynamics of Landscape Ecological Security

Directory of Open Access Journals (Sweden)

Yi Lu

2016-11-01

Full Text Available Urban ecological security is the basic principle of national ecological security. However, analyses of the spatial and temporal dynamics of ecological security remain limited, especially those that consider different scenarios of urban development. In this study, an integrated method is proposed that combines the Conversion of Land Use and its Effects (CLUE-S model with the Pressure–State–Response (P-S-R framework to assess landscape ecological security (LES in Huangshan City, China under two scenarios. Our results suggest the following conclusions: (1 the spatial and temporal dynamics of ecological security are closely related to the urbanization process; (2 although the average values of landscape ecological security are similar under different scenarios, the areas of relatively high security levels vary considerably; and (3 spatial heterogeneity in ecological security exists between different districts and counties, and the city center and its vicinity may face relatively serious declines in ecological security in the future. Overall, the proposed method not only illustrates the spatio-temporal dynamics of landscape ecological security under different scenarios but also reveals the anthropogenic effects on ecosystems by differentiating between causes, effects, and human responses at the landscape scale. This information is of great significance to decision-makers for future urban planning and management.

Landscape ecological planning: Integrating land use and wildlife conservation for biomass crops

Energy Technology Data Exchange (ETDEWEB)

Schiller, A.

1995-12-31

What do a mussel shoat, a zoo, and a biomass plantation have in common? Each can benefit from ecology-based landscape planning. This paper provides examples of landscape ecological planning from some diverse projects the author has worked on, and discusses how processes employed and lessons learned from these projects are being used to help answer questions about the effects of biomass plantings (hardwood tree crops and native grasses) on wildlife habitat. Biomass environmental research is being designed to assess how plantings of different acreage, composition and landscape context affect wildlife habitat value, and is addressing the cumulative effect on wildlife habitat of establishing multiple biomass plantations across the landscape. Through landscape ecological planning, answers gleaned from research can also help guide biomass planting site selection and harvest strategies to improve habitat for native wildlife species within the context of economically viable plantation management - thereby integrating the needs of people with those of the environment.

Integrating models with data in ecology and palaeoecology: advances towards a model-data fusion approach.

Science.gov (United States)

Peng, Changhui; Guiot, Joel; Wu, Haibin; Jiang, Hong; Luo, Yiqi

2011-05-01

It is increasingly being recognized that global ecological research requires novel methods and strategies in which to combine process-based ecological models and data in cohesive, systematic ways. Model-data fusion (MDF) is an emerging area of research in ecology and palaeoecology. It provides a new quantitative approach that offers a high level of empirical constraint over model predictions based on observations using inverse modelling and data assimilation (DA) techniques. Increasing demands to integrate model and data methods in the past decade has led to MDF utilization in palaeoecology, ecology and earth system sciences. This paper reviews key features and principles of MDF and highlights different approaches with regards to DA. After providing a critical evaluation of the numerous benefits of MDF and its current applications in palaeoecology (i.e., palaeoclimatic reconstruction, palaeovegetation and palaeocarbon storage) and ecology (i.e. parameter and uncertainty estimation, model error identification, remote sensing and ecological forecasting), the paper discusses method limitations, current challenges and future research direction. In the ongoing data-rich era of today's world, MDF could become an important diagnostic and prognostic tool in which to improve our understanding of ecological processes while testing ecological theory and hypotheses and forecasting changes in ecosystem structure, function and services. © 2011 Blackwell Publishing Ltd/CNRS.

Isotopes and Radiation in Entomology. Proceedings of a Symposium on the Use of Isotopes and Radiation in Entomology

Energy Technology Data Exchange (ETDEWEB)

NONE

1968-06-15

Proceedings of a Symposium jointly organized by the IAEA and the Food and Agriculture Organization of the United Nations and held in Vienna, 4-8 December 1967. The meeting was attended by 82 participants from 29 countries and six international organizations. Contents: Isotope applications - ecology (7 papers); Radiation effect studies - non-genetic (8 papers); Isotope applications - physiology and biochemistry (2 papers); Isotope applications - chemosterilants (2 papers); Sterile-male technique (9 papers); Radiation effect studies - genetic (5 papers); Isotope applications - genetic (1 paper). Each paper is in its original language (21 English, 11 French, 1 Russian and 1 Spanish) and is preceded by an abstract in English with a second one in the original language if this is not English. Discussions are in English. (author)

High-frequency field-deployable isotope analyzer for hydrological applications

Science.gov (United States)

Elena S.F. Berman; Manish Gupta; Chris Gabrielli; Tina Garland; Jeffrey J. McDonnell

2009-01-01

A high-frequency, field-deployable liquid water isotope analyzer was developed. The instrument was deployed for 4 contiguous weeks in the H. J. Andrews Experimental Forest Long-term Ecological Research site in western Oregon, where it was used for real-time measurement of the isotope ratios of precipitation and stream water during three large storm events. We were able...

Use of isotopes in fisheries research

International Nuclear Information System (INIS)

Ayyappan, S.

2001-01-01

Fisheries is an interdisciplinary science, incorporating not only different aspect of biology like anatomy, physiology, ecology, etc., but also oceanography, biochemistry, biotechnology and such emerging areas in the recent years. Isotopes are being employed for a variety of studies like quantification of aquatic production processes, nutrient cycles and food chain dynamics (primary production, bacterial activity, sediment-water nutrient interactions, nitrification, fertilizer use efficiencies, organic mineralisation, amino acid uptake in algal-bacterial assemblages, hydrological studies including water transport and budgeting, partitioning of trophic pathways), fish nutrition (feed utility and digestibility), fatty acid metabolism, compartmentalization of food spectra in different species of fish and shellfish), fish physiology, genetics and immunology (radioimmunoassay, enzyme assays, evaluation of hormone levels, gene markers -DNA labeling and plasmid incorporation, immuno diagnostics), fish health management and pollution (host-parasite interactions chemical/pesticide uptake and accumulation), etc. Radioisotopes commonly used in ecological studies are beta emitters like 14 C, 3 H, 32 P and 35 S, while a stable isotope like 15 N is used in quantifying nitrogen fixation rates in water and sediment media. Results of some of the studies and potential applications of isotopes in fish research are presented. (author)

Methodological validation of the isotopic analysis of fossil bones and contributions to the paleo-ecological reconstitutions of the Upper Paleolithic of south-west France; Validation methodologique de l'analyse isotopique d'ossements fossiles et apports aux reconstitutions paleoecologiques du paleolithique superieur du sud-ouest de la France

Energy Technology Data Exchange (ETDEWEB)

Drucker, D

2001-04-01

A methodology for investigating fossil bone collagen carbon and nitrogen isotopic signatures has been established in order to obtain palaeo-ecological informations. The archaeological, biochemical and geochemical reliability has been estimated. Almost 500 animal and human specimens from southwestern France upper Palaeolithic sites ranging in age from 36,000 to 9,000 years BP have been treated. It has been demonstrated that different dietary resources were isotopically distinct, with a resolution better than the expectations. Small mammals have been distinguished from ungulates, and Reindeer, Horse and Bovines presented specific isotopic signatures. Moreover, isotopic differences have been evidenced between gregarious and solitary species. Time changes of ecological patterns have been described using the isotopic signatures of some mammal species. Biomass fluctuation and exploitation have been demonstrated during upper Palaeolithic. The methodology allowed to use the isotopic signatures of animal predators as a proxy for meat resources availability in the environment. This approach allows to investigate environmental global factors as well as human behaviour with a common tool. (author)

Microbial ecology of denitrification in biological wastewater treatment.

Science.gov (United States)

Lu, Huijie; Chandran, Kartik; Stensel, David

2014-11-01

Globally, denitrification is commonly employed in biological nitrogen removal processes to enhance water quality. However, substantial knowledge gaps remain concerning the overall community structure, population dynamics and metabolism of different organic carbon sources. This systematic review provides a summary of current findings pertaining to the microbial ecology of denitrification in biological wastewater treatment processes. DNA fingerprinting-based analysis has revealed a high level of microbial diversity in denitrification reactors and highlighted the impacts of carbon sources in determining overall denitrifying community composition. Stable isotope probing, fluorescence in situ hybridization, microarrays and meta-omics further link community structure with function by identifying the functional populations and their gene regulatory patterns at the transcriptional and translational levels. This review stresses the need to integrate microbial ecology information into conventional denitrification design and operation at full-scale. Some emerging questions, from physiological mechanisms to practical solutions, for example, eliminating nitrous oxide emissions and supplementing more sustainable carbon sources than methanol, are also discussed. A combination of high-throughput approaches is next in line for thorough assessment of wastewater denitrifying community structure and function. Though denitrification is used as an example here, this synergy between microbial ecology and process engineering is applicable to other biological wastewater treatment processes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Integrating Ecological and Social Ranges of Variability in Conservation of Biodiversity: Past, Present, and Future

Directory of Open Access Journals (Sweden)

Sally L. Duncan

2010-03-01

Full Text Available Historical range of variability has been proposed as a concept that can be used by forest land managers to guide conservation of ecosystem functions and biodiversity conservation. The role of humans in historical range of variability has remained somewhat murky and unsettled, even though it is clear that humans have been, are, and will continue to be forces of disturbance and recovery in forested landscapes. We attempt to develop concepts that integrate the ecological and social forces affecting landscape variability. Toward that end, we present a conceptual framework that places "range of variability" into a broader context and integrates the ecological and social forces affecting landscapes past, present, and future. We use two terms to aid us in understanding the utility of historical range of variability as a context and future range of variability as a point of comparison: (1 the ecological range of variability is the estimated range of some ecological condition as a function of the biophysical and social forces affecting the area and (2 the social range of variability is the range of an ecological condition that society finds acceptable at a given time. We find it is important to recognize that future range of variability represents a constantly emerging and changing set of conditions, and that the more humans push a system to depart from its historical range of variabiloity domain, the less likely it becomes that historical range of variability processes will prove useful as benchmarks in recovering a system.

Integrated Ecological-Economic Modeling of Regions with the use of GIS Technologies

Directory of Open Access Journals (Sweden)

G.N. Bulatova

2017-11-01

Full Text Available The paper shows the process of modeling the integrated map “Scheme of the ecological and economic regionalization of the territory of the Russian Federation on the basis of the mineral and raw materials base of natural adsorbents” using GIS technologies. The map is based on three main groups of indicators: natural, economic and environmental. The ecological content of the map is characterized by indicators that are potential or actual sources of pollutant release into the environment (nuclear power plants, nuclear reactors, radioactive waste storage and disposal sites, nuclear test sites, industrial enterprises, railways, operating and under construction oil pipelines, hydrocarbon fields, etc.. The economic component of the map is the reserves estimated by the indicators of study and development, the relationship to the subsoil fund and forecast resources. The natural group of indicators is represented by the mineral and raw material base of natural adsorbents (fields and objects of forecast resources that can be used to prevent harmful emissions and for the ecological and economic rehabilitation of contaminated areas. Based on the analysis of cartographic data, the ecological and economic areas of the territorial distribution of man-caused environmental impacts and the presence of adsorption raw materials are identified. As an example, a description is given of the ecological and economic model of the regionalization of the Privolzhsky Federal District using the GIS “Mineral resource base of natural adsorbents of Russia” developed at the Federal State Unitary Enterprise TsNIIgeolnerud.

Towards Integrating Political Ecology into Resilience-Based Management

OpenAIRE

Amy Quandt

2016-01-01

One of the biggest challenges faced today is how to sustainably manage social-ecological systems for both ecological conservation and human wellbeing. This paper explores two approaches to understanding such systems: resilience thinking and political ecology. Resilience thinking is a framework that emerged over the last 40 years as a management strategy for social-ecological systems, and a resilient social-ecological system is capable of absorbing disturbances and still retaining its basic fu...

Integration of Local Ecological Knowledge and Conventional Science: a Study of Seven Community-Based Forestry Organizations in the USA

Directory of Open Access Journals (Sweden)

Heidi L. Ballard

2008-12-01

Full Text Available Natural resource management decisions can be based on incomplete knowledge when they lack scientific research, monitoring, and assessment and/or simultaneously fail to draw on local ecological knowledge. Many community-based forestry organizations in the United States attempt to address these knowledge gaps with an integrated ecological stewardship approach that balances ecological, social, and economic goals. This paper examines the use and integration of local knowledge and conventional science in ecological stewardship and monitoring by seven community-based forestry demonstration projects. Through document reviews and interviews with both participants and partners of all of these community-based organizations, we found that all the community-based forestry groups incorporated local ecological knowledge into many aspects of their management or monitoring activities, such as collaboratively designing monitoring programs with local ranchers, forest workers, and residents; involving local people in collecting data and interpreting results; and documenting the local ecological knowledge of private forest landowners, long-time residents, and harvesters of nontimber forest products. We found that all the groups also used conventional science to design or conduct ecological assessments, monitoring, or research. We also found evidence, in the form of changes in attitudes on the part of local people and conventional scientists and jointly produced reports, that the two types of knowledge were integrated by all groups. These findings imply that community-based forestry groups are redistributing the power of conventional science through the use of diverse knowledge sources. Still, several obstacles prevented some local, traditionally under-represented groups from being significantly involved in monitoring and management decisions, and their knowledge has not yet been consistently incorporated.

[Urban ecological risk assessment: a review].

Science.gov (United States)

Wang, Mei-E; Chen, Wei-Ping; Peng, Chi

2014-03-01

With the development of urbanization and the degradation of urban living environment, urban ecological risks caused by urbanization have attracted more and more attentions. Based on urban ecology principles and ecological risk assessment frameworks, contents of urban ecological risk assessment were reviewed in terms of driven forces, risk resources, risk receptors, endpoints and integrated approaches for risk assessment. It was suggested that types and degrees of urban economical and social activities were the driven forces for urban ecological risks. Ecological functional components at different levels in urban ecosystems as well as the urban system as a whole were the risk receptors. Assessment endpoints involved in changes of urban ecological structures, processes, functional components and the integrity of characteristic and function. Social-ecological models should be the major approaches for urban ecological risk assessment. Trends for urban ecological risk assessment study should focus on setting a definite protection target and criteria corresponding to assessment endpoints, establishing a multiple-parameter assessment system and integrative assessment approaches.

Forward Modeling of Carbonate Proxy Data from Planktonic Foraminifera using Oxygen Isotope Tracers in a Global Ocean Model

Science.gov (United States)

Schmidt, Gavin A.

1999-01-01

The distribution and variation of oxygen isotopes in seawater are calculated using the Goddard Institute for Space Studies global ocean model. Simple ecological models are used to estimate the planktonic foraminiferal abundance as a function of depth, column temperature, season, light intensity, and density stratification. These models are combined to forward model isotopic signals recorded in calcareous ocean sediment. The sensitivity of the results to the changes in foraminiferal ecology, secondary calcification, and dissolution are also examined. Simulated present-day isotopic values for ecology relevant for multiple species compare well with core-top data. Hindcasts of sea surface temperature and salinity are made from time series of the modeled carbonate isotope values as the model climate changes. Paleoclimatic inferences from these carbonate isotope records are strongly affected by erroneous assumptions concerning the covariations of temperature, salinity, and delta (sup 18)O(sub w). Habitat-imposed biases are less important, although errors due to temperature-dependent abundances can be significant.

Assessing the Ecological Integrity of a Major Transboundary Mediterranean River Based on Environmental Habitat Variables and Benthic Macroinvertebrates (Aoos-Vjose River, Greece-Albania)

NARCIS (Netherlands)

Chatzinikolaou, Y.; Dakos, V.; Lazaridou-Dimitriadou, M.

2008-01-01

Ecological integrity has become a primary objective in monitoring programs of surface waters according to the European Water Framework Directive. For this reason we propose a scheme for assessing the ecological integrity of a major transboundary river, the Aoos-Vjose (Greece-Albania), by analysing

Integrating continental-scale ecological data into university courses: Developing NEON's Online Learning Portal

Science.gov (United States)

Wasser, L. A.; Gram, W.; Lunch, C. K.; Petroy, S. B.; Elmendorf, S.

2013-12-01

'Big Data' are becoming increasingly common in many fields. The National Ecological Observatory Network (NEON) will be collecting data over the 30 years, using consistent, standardized methods across the United States. Similar efforts are underway in other parts of the globe (e.g. Australia's Terrestrial Ecosystem Research Network, TERN). These freely available new data provide an opportunity for increased understanding of continental- and global scale processes such as changes in vegetation structure and condition, biodiversity and landuse. However, while 'big data' are becoming more accessible and available, integrating big data into the university courses is challenging. New and potentially unfamiliar data types and associated processing methods, required to work with a growing diversity of available data, may warrant time and resources that present a barrier to classroom integration. Analysis of these big datasets may further present a challenge given large file sizes, and uncertainty regarding best methods to properly statistically summarize and analyze results. Finally, teaching resources, in the form of demonstrative illustrations, and other supporting media that might help teach key data concepts, take time to find and more time to develop. Available resources are often spread widely across multi-online spaces. This presentation will overview the development of NEON's collaborative University-focused online education portal. Portal content will include 1) interactive, online multi-media content that explains key concepts related to NEON's data products including collection methods, key metadata to consider and consideration of potential error and uncertainty surrounding data analysis; and 2) packaged 'lab' activities that include supporting data to be used in an ecology, biology or earth science classroom. To facilitate broad use in classrooms, lab activities will take advantage of freely and commonly available processing tools, techniques and scripts. All

Biogeochemical Indicators in High- and Low-Arctic Marine and Terrestrial Avian Community Changes: Comparative Isotopic (13C, 15N, and 34S) Studies in Alaska and Greenland

Science.gov (United States)

Causey, D.; Bargmann, N. A.; Burnham, K. K.; Burnham, J. L.; Padula, V. M.; Johnson, J. A.; Welker, J. M.

2011-12-01

Understanding the complex dynamics of environmental change in northern latitudes is of paramount importance today, given documented rapid shifts in sea ice, plant phenology, temperatures, deglaciation, and habitat fidelity. This knowledge is particularly critical for Arctic avian communities, which are integral components by which biological teleconnections are maintained between the mid and northern latitudes. Furthermore, Arctic birds are fundamental to Native subsistence lifestyles and a focus for conservation activities. Avian communities of marine and terrestrial Arctic environments represent a broad spectrum of trophic levels, from herbivores (eg., geese Chen spp.), planktivores (eg., auklets Aethia spp.), and insectivores (eg., passerines: Wheatears Oenanthe spp., Longspurs Calcarius spp.), to predators of marine invertebrates (eg., eiders Somateria spp.), nearshore and offshore fish (eg., cormorants Phalacrocorax spp, puffins Fratercula spp.), even other bird species (eg., gulls Larus spp., falcons Peregrinus spp.). This diversity of trophic interconnections is an integral factor in the dynamics of Arctic ecosystem ecology, and they are key indicators for the strength and trajectories of change. We are especially interested in their feeding ecology, using stable isotope-diet relations to examine historical diets and to predict future feeding ecology by this range of species. Since 2009, we have been studying the foodweb ecology using stable isotopes (δ13C, δ15N, δ34S) of contemporaneous coastal and marine bird communities in High Arctic (Northwest Greenland) and Low Arctic (western Aleutian Islands, AK). We are quantifying the isotopic values of blood, organ tissues, and feathers, and have carried out comparisons between native and lipid-extracted samples. Although geographically distant, these communities comprise similar taxonomic and ecological congeners, including several species common to both (eg., Common Eider, Black-legged Kittiwake, Northern

Integrating an ecological approach into an Aboriginal community-based chronic disease prevention program: a longitudinal process evaluation

Directory of Open Access Journals (Sweden)

Maypilama Elaine

2011-05-01

Full Text Available Abstract Background Public health promotes an ecological approach to chronic disease prevention, however, little research has been conducted to assess the integration of an ecological approach in community-based prevention programs. This study sought to contribute to the evidence base by assessing the extent to which an ecological approach was integrated into an Aboriginal community-based cardiovascular disease (CVD and type 2 diabetes prevention program, across three-intervention years. Methods Activity implementation forms were completed by interview with implementers and participant observation across three intervention years. A standardised ecological coding procedure was applied to assess participant recruitment settings, intervention targets, intervention strategy types, extent of ecologicalness and organisational partnering. Inter-rater reliability for two coders was assessed at Kappa = 0.76 (p Results 215 activities were implemented across three intervention years by the health program (HP with some activities implemented in multiple years. Participants were recruited most frequently through organisational settings in years 1 and 2, and organisational and community settings in year 3. The most commonly utilised intervention targets were the individual (IND as a direct target, and interpersonal (INT and organisational (ORG environments as indirect targets; policy (POL, and community (COM were targeted least. Direct (HP→ IND and indirect intervention strategies (i.e., HP→ INT→ IND, HP→ POL → IND were used most often; networking strategies, which link at least two targets (i.e., HP→[ORG-ORG]→IND, were used the least. The program did not become more ecological over time. Conclusions The quantity of activities with IND, INT and ORG targets and the proportion of participants recruited through informal cultural networking demonstrate community commitment to prevention. Integration of an ecological approach would have been

The ecological economics: An ecological economics

International Nuclear Information System (INIS)

Castiblanco R, Carmenza

2007-01-01

Ecological Economics arise as a scientific discipline aimed to integrate concepts of economics, ecology, thermodynamics, ethic and other natural and social sciences in order to incorporate a biophysical and integrated perspective of the inter dependences between economies and environment, from a plural conception and a methodology beyond disciplines. Ecological Economics studies the black box of economic processes usually excluded of the traditional economics: thermodynamics and ecology. Although it is relatively a new field of study, it has been strengthening its theoretical framework with scientific basis and analytic principles that lead to its identification as a new discipline that show a whole new paradigm. The scope of this article is to show the conceptual and methodological bases, the main founders, approaches and central debates of this new discipline. This brief introduction is a preamble to the papers of the meeting Ecological Economics: a perspective for Colombia included in this number, that took place on September 22 - 27 of 2007, at the National University of Colombia at Bogota. During tree days national and international experts, professors, researchers, workers of environmental sector and people interested on environmental issues joined together to know the conceptual and methodological achievements reached of this discipline; as well as to analyse and evaluate the environmental problems of the country, from the systemic, interdisciplinary and general perspective that it promotes

EVALUATING THE ECOLOGICAL RESILIENT DRIVEN PERFORMANCE OF A TROPICAL WASTE STABILIZATION POND SYSTEM USING ECOLOGICAL SIGNATURE OF BIOLOGICAL INTEGRITY

OpenAIRE

Susmita Lahiri Ganguly; Dipanwita Sarkar Paria; B. B. Jana

2015-01-01

Using ecological signature of biological integrity as a measure of performance, the reclamation efficiency of waste stabilization ponds was evaluated over a period of four years in a tropical sewage treatment plant – cum fish culture consisting of two anaerobic, two facultative and four maturation ponds located serially across the sewage effluent gradient. The four maturation ponds were used for batch culture of fish. Samples of surface and bottom water as well as surface sediment were collec...

Stable Isotopes from Museum Specimens May Provide Evidence of Long-Term Change in the Trophic Ecology of a Migratory Aerial Insectivore

Directory of Open Access Journals (Sweden)

Philina A. English

2018-02-01

Full Text Available Identifying the mechanisms of ecological change is challenging in the absence of long-term data, but stable isotope ratios of museum specimen tissues may provide a record of diet and habitat change through time. Aerial insectivores are experiencing the steepest population declines of any avian guild in North America and one hypothesis for these population declines is a reduction in the availability of prey. If reduced prey availability is due to an overall reduction in insect abundance, we might also expect populations of higher trophic level insects to have declined most due to their greater sensitivity to a variety of disturbance types. Because nitrogen isotope ratios (δ15N tend to increase with trophic-level, while δ13C generally increases with agricultural intensification, we used δ15N and δ13C values of bird tissues grown in winter (claw and during breeding (feathers from museum specimens spanning 1880–2005, and contemporary samples from breeding birds (2011–2013 to test for diet change in a migratory nocturnal aerial insectivore, Eastern Whip-poor-will (Antrostomus vociferus breeding in Ontario, Canada. To test if environmental baselines have changed as a result of synthetic N fertilizer use, habitat conversion or climate, we also sampled δ15N values of three potential prey species collected from across the same geographic region and time period. Over the past 100 years, we found a significant decline in δ15N in tissues grown on both the breeding and wintering grounds. Prey species did not show a corresponding temporal trend in δ15N values, but our power to detect such a trend was limited due to higher sample variance. Amongst contemporary bird samples, δ15N values did not vary with sex or breeding site, but nestlings had lower δ15N values than adults. These results are consistent with the hypothesis that aerial insectivore populations are declining due to changes in abundance of higher trophic-level prey, but we caution that

Frogs, fish and forestry: An integrated watershed network paradigm conserves biodiversity and ecological services

Science.gov (United States)

Hartwell H. Welsh Jr.

2011-01-01

Successfully addressing the multitude of stresses influencing forest catchments, their native biota, and the vital ecological services they provide humanity will require adapting an integrated view that incorporates the full range of natural and anthropogenic disturbances acting on these landscapes and their embedded fluvial networks. The concepts of dendritic networks...

First stable isotope analysis of Asiatic wild ass tail hair from the Mongolian Gobi.

Science.gov (United States)

Horacek, Micha; Sturm, Martina Burnik; Kaczensky, Petra

Stable isotope analysis has become a powerful tool to study feeding ecology, water use or movement pattern in contemporary, historic and ancient species. Certain hair and teeth grow continuously, and when sampled longitudinally can provide temporally explicit information on dietary regime and movement pattern. In an initial trial, we analysed a tail sample of an Asiatic wild ass ( Equus hemionus ) from the Mongolian Gobi. We found seasonal variations in H, C and N isotope patterns, likely being the result of temporal variations in available feeds, water supply and possibly physiological status. Thus stable isotope analysis shows promise to study the comparative ecology of the three autochthonous equid species in the Mongolian Gobi.

EVALUATING THE ECOLOGICAL RESILIENT DRIVEN PERFORMANCE OF A TROPICAL WASTE STABILIZATION POND SYSTEM USING ECOLOGICAL SIGNATURE OF BIOLOGICAL INTEGRITY

Directory of Open Access Journals (Sweden)

Susmita Lahiri Ganguly

2015-06-01

Full Text Available Using ecological signature of biological integrity as a measure of performance, the reclamation efficiency of waste stabilization ponds was evaluated over a period of four years in a tropical sewage treatment plant – cum fish culture consisting of two anaerobic, two facultative and four maturation ponds located serially across the sewage effluent gradient. The four maturation ponds were used for batch culture of fish. Samples of surface and bottom water as well as surface sediment were collected twice a month from different ponds of the system and examined for some nutrient cycling bacteria, primary production, chlorophyll content of micro-algae, phytoplankton, zooplankton abundance, fish growth and water quality parameters. Computation of ecological signature using aerobic mineralization index for heterotrophic and ammonifying bacteria revealed steady increase across the sewage effluent gradient. The heterotrophic and ammonifying bacterial populations appeared to have a direct function with the concentrations of chemical oxygen demand of water. The sum of total scores for different optimal conditions for fish growth increased as a function of the distance from the source of effluent implying that ecological resilience of the waste stabilization ponds has been accomplished by the sedimentation, chelation, and biological functional attributes mediated through redundancy of different subsystems, self- purification capacity of the system as a whole.

Program on ecosystem change and society: An international research strategy for integrated social-ecological systems

NARCIS (Netherlands)

Carpenter, S.R.; Folke, C.; Norström, A.V.; Olsson, O.; Schultz, L.; Agarwal, B.; Balvanera, P.; Campbell, B.; Castilla, J.C.; Cramer, W.; DeFries, R.; Eyzaguirre, P.; Hughes, T.P.; Polasky, S.; Sanusi, Z.A.; Scholes, R.J.; Spierenburg, M.J.

2012-01-01

The Program on Ecosystem Change and Society (PECS), a new initiative within the ICSU global change programs, aims to integrate research on the stewardship of social-ecological systems, the services they generate, and the relationships among natural capital, human wellbeing, livelihoods, inequality

Program on ecosystem change and society: an international research strategy for integrated social–ecological systems

NARCIS (Netherlands)

Carpenter, S.R; Folke, C.; Nordström, A.; Olsson, O.; Schultz, L.; Agarwal, B.; Balvanera, P.; Campbell, B.; Castilla, J.C.; Cramer, W.; DeFries, R.; Eyzaguirre, P.; Hughes, T.P.; Polasky, S.; Sanusi, Z.; Spierenburg, M.J.

2012-01-01

The Program on Ecosystem Change and Society (PECS), a new initiative within the ICSU global change programs, aims to integrate research on the stewardship of social-ecological systems, the services they generate, and the relationships among natural capital, human wellbeing, livelihoods, inequality

Ecological quality assessment of rivers and integrated catchment management in England and Wales

Directory of Open Access Journals (Sweden)

Paul LOGAN

2001-09-01

Full Text Available This paper deals with the ecological assessment of river quality and its relationship to integrated catchment management. The concept of catchment or river basin management has been a basic management tool in England and Wales since 1990; it is now being enshrined in the Water Framework Directive. Historically the statutory and operational drivers in the UK have lead to the development of distinctly different approaches to the management of water quality, water resources (quantity and physical river structure. More recently a proactive approach to the sustainable use of water promulgated in the Local Environment Agency Plans has also dealt with the three management aspects in some isolation although greater effort has been made to present the issues in an integrated manner. The Water Framework Directive calls for further integration in river basin plans and associated programmes of measures. In the paper the three approaches are described and considered in light of the requirements of the Water Framework Directive. Water Quality classification and objective setting has been based on information from the survey of benthic macro-invertebrates. The Biological Monitoring Working Party Score and the predictive software River Invertebrate Prediction and Classification System (RIVPACS have been used to set site-specific targets for management purposes. RIVPACS includes a reference database of minimally impacted sites for comparison with the observed data. This approach is in line with the requirements of the directive. Physical river structure work has been based on monitoring of in-river and river corridor characteristics. The River Habitat System (RHS has also developed a reference database but is less well developed in terms of its predictive ability. The use of ecological information in Water Resource management has taken a different approach based on the concept of differential ecological sensitivity to the hydrological regime within the river. In

The EU as a global ecological power: The logics of market integration

International Nuclear Information System (INIS)

Laurent, Eloi; Le Cacheux, Jacques

2010-05-01

In this paper, we try to show how the EU became a global ecological power, i.e. a power that influences environmental policies throughout the world. While the existing literature stresses the significance of normative power, regulatory politics and multi-level governance in this process, we highlight the importance of what we call the logics of market integration. By that we mean the decisive role of Single market integration in fostering convergence of environmental policies at the European level as well as in extending European influence at the global level. We illustrate our approach with the case of climate policy, detailing the EU's influence on economic instruments developed worldwide to mitigate climate change. (authors)

Run-off analyses using isotopes and hydrochemistry in Yushugou ...

Indian Academy of Sciences (India)

Xiaoyan Wang

2017-08-31

Aug 31, 2017 ... Key Laboratory for Ecology and Environment of River Wetlands in Shaanxi Province, ... Stable isotopes; run-off composition; hydrograph separation; Yushugou River basin. ..... rock weathering and hydrogeological condition in.

The Importance of Ecology-Based Nature Education Project in Terms of Nature Integration and Understanding the Human-Ecosystem Relationship

Science.gov (United States)

Meydan, Ali

2011-01-01

The aim of this project is to define the importance of 12-day ecology-based education training upon integration with nature and understanding the human-ecosystem relationship. In accordance with this purpose, there has been collected some survey data interviewing with the participants of "Lake Beysehir National Park and Ecology-based Nature…

Toward molecular trait-based ecology through integration of biogeochemical, geographical and metagenomic data

DEFF Research Database (Denmark)

Raes, Jeroen; Letunic, Ivica; Yamada, Takuji

2011-01-01

Using metagenomic 'parts lists' to infer global patterns on microbial ecology remains a significant challenge. To deduce important ecological indicators such as environmental adaptation, molecular trait dispersal, diversity variation and primary production from the gene pool of an ecosystem, we...... integrated 25 ocean metagenomes with geographical, meteorological and geophysicochemical data. We find that climatic factors (temperature, sunlight) are the major determinants of the biomolecular repertoire of each sample and the main limiting factor on functional trait dispersal (absence of biogeographic...... provincialism). Molecular functional richness and diversity show a distinct latitudinal gradient peaking at 20° N and correlate with primary production. The latter can also be predicted from the molecular functional composition of an environmental sample. Together, our results show that the functional community...

Stable isotopes and elasmobranchs: tissue types, methods, applications and assumptions.

Science.gov (United States)

Hussey, N E; MacNeil, M A; Olin, J A; McMeans, B C; Kinney, M J; Chapman, D D; Fisk, A T

2012-04-01

Stable-isotope analysis (SIA) can act as a powerful ecological tracer with which to examine diet, trophic position and movement, as well as more complex questions pertaining to community dynamics and feeding strategies or behaviour among aquatic organisms. With major advances in the understanding of the methodological approaches and assumptions of SIA through dedicated experimental work in the broader literature coupled with the inherent difficulty of studying typically large, highly mobile marine predators, SIA is increasingly being used to investigate the ecology of elasmobranchs (sharks, skates and rays). Here, the current state of SIA in elasmobranchs is reviewed, focusing on available tissues for analysis, methodological issues relating to the effects of lipid extraction and urea, the experimental dynamics of isotopic incorporation, diet-tissue discrimination factors, estimating trophic position, diet and mixing models and individual specialization and niche-width analyses. These areas are discussed in terms of assumptions made when applying SIA to the study of elasmobranch ecology and the requirement that investigators standardize analytical approaches. Recommendations are made for future SIA experimental work that would improve understanding of stable-isotope dynamics and advance their application in the study of sharks, skates and rays. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

Landscape Ecology

DEFF Research Database (Denmark)

Christensen, Andreas Aagaard; Brandt, Jesper; Svenningsen, Stig Roar

2017-01-01

Landscape ecology is an interdisciplinary field of research and practice that deals with the mutual association between the spatial configuration and ecological functioning of landscapes, exploring and describing processes involved in the differentiation of spaces within landscapes......, and the ecological significance of the patterns which are generated by such processes. In landscape ecology, perspectives drawn from existing academic disciplines are integrated based on a common, spatially explicit mode of analysis developed from classical holistic geography, emphasizing spatial and landscape...... pattern analysis and ecological interaction of land units. The landscape is seen as a holon: an assemblage of interrelated phenomena, both cultural and biophysical, that together form a complex whole. Enduring challenges to landscape ecology include the need to develop a systematic approach able...

Feasibility analysis of marine ecological on-line integrated monitoring system

Science.gov (United States)

Chu, D. Z.; Cao, X.; Zhang, S. W.; Wu, N.; Ma, R.; Zhang, L.; Cao, L.

2017-08-01

The in-situ water quality sensors were susceptible to biological attachment. Moreover, sea water corrosion and wave impact damage, and many sensors scattered distribution would cause maintenance inconvenience. The paper proposed a highly integrated marine ecological on-line integrated monitoring system, which can be used inside monitoring station. All sensors were reasonably classified, the similar in series, the overall in parallel. The system composition and workflow were described. In addition, the paper proposed attention issues of the system design and corresponding solutions. Water quality multi-parameters and 5 nutrient salts as the verification index, in-situ and systematic data comparison experiment were carried out. The results showed that the data consistency of nutrient salt, PH and salinity was better. Temperature and dissolved oxygen data trend was consistent, but the data had deviation. Turbidity fluctuated greatly; the chlorophyll trend was similar with it. Aiming at the above phenomena, three points system optimization direction were proposed.

Dual isotope notch observer for isotope identification, assay and imaging with mono-energetic gamma-ray sources

Science.gov (United States)

Barty, Christopher P.J.

2013-02-05

A dual isotope notch observer for isotope identification, assay and imaging with mono-energetic gamma-ray sources includes a detector arrangement consists of three detectors downstream from the object under observation. The latter detector, which operates as a beam monitor, is an integrating detector that monitors the total beam power arriving at its surface. The first detector and the middle detector each include an integrating detector surrounding a foil. The foils of these two detectors are made of the same atomic material, but each foil is a different isotope, e.g., the first foil may comprise U235 and second foil may comprise U238. The integrating detectors surrounding these pieces of foil measure the total power scattered from the foil and can be similar in composition to the final beam monitor. Non-resonant photons will, after calibration, scatter equally from both foils.

Predicting rates of isotopic turnover across the animal kingdom: a synthesis of existing data.

Science.gov (United States)

Thomas, Stephen M; Crowther, Thomas W

2015-05-01

The stable isotopes of carbon ((12)C, (13)C) and nitrogen ((14)N, (15)N) represent powerful tools in food web ecology, providing a wide range of dietary information in animal consumers. However, identifying the temporal window over which a consumer's isotopic signature reflects its diet requires an understanding of elemental incorporation, a process that varies from days to years across species and tissue types. Though theory predicts body size and temperature are likely to control incorporation rates, this has not been tested empirically across a morphologically and phylogenetically diverse range of taxa. Readily available estimates of this relationship would, however, aid in the design of stable isotope food web investigations and improve the interpretation of isotopic data collected from natural systems. Using literature-derived turnover estimates from animal species ranging in size from 1 mg to 2000 kg, we develop a predictive tool for stable isotope ecologists, allowing for estimation of incorporation rates in the structural tissues of entirely novel taxa. In keeping with metabolic scaling theory, we show that isotopic turnover rates of carbon and nitrogen in whole organisms and muscle tissue scale allometrically with body mass raised approximately to the power -0.19, an effect modulated by body temperature. This relationship did not, however, apply to incorporation rates in splanchnic tissues, which were instead dependent on the thermoregulation tactic employed by an organism, being considerably faster in endotherms than ectotherms. We believe the predictive turnover equations we provide can improve the design of experiments and interpretation of results obtained in future stable isotopic food web studies. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Stable isotope ecology of Miocene bovids from Northern Greece and the ape/monkey turnover in the Balkans.

Science.gov (United States)

Merceron, Gildas; Kostopoulos, Dimitris S; Bonis, Louis de; Fourel, François; Koufos, George D; Lécuyer, Christophe; Martineau, François

2013-08-01

Eurasia was home to a great radiation of hominoid primates during the Miocene. All were extinct by the end of the Miocene in Western Eurasia. Here, we investigate the hypothesis of climate and vegetation changes at a local scale when the cercopithecoid Mesopithecus replaced the hominoid Ouranopithecus along the Axios River, Greece. Because they are herbivorous and were much more abundant than primates, bovids are preferred to primates to study climate change in the Balkans as a cause of hominoid extinction. By measuring carbon stable isotope ratios of bovid enamel, we conclude that Ouranopithecus and Mesopithecus both evolved in pure C3 environments. However, the large range of δ(13)C values of apatite carbonate from bovids combined with their molar microwear and mesowear patterns preclude the presence of dense forested landscapes in northern Greece. Instead, these bovids evolved in rather open landscapes with abundant grasses in the herbaceous layer. Coldest monthly estimated temperatures were below 10°C and warmest monthly temperatures rose close to or above 20°C for the two time intervals. Oxygen isotope compositions of phosphate from bulk samples did not show significant differences between sites but did show between-species variation within each site. Different factors influence oxygen isotope composition in this context, including water provenience, feeding ecology, body mass, and rate of amelogenesis. We discuss this latter factor in regard to the high intra-tooth variations in δ(18)Op reflecting important amplitudes of seasonal variations in temperature. These estimations fit with paleobotanical data and differ slightly from estimations based on climate models. This study found no significant change in climate before and after the extinction of Ouranopithecus along the Axios River. However, strong seasonal variations with relatively cold winters were indicated, conditions quite usual for extant monkeys but unusual for great apes distributed today in

Integrating survey and molecular approaches to better understand wildlife disease ecology.

Directory of Open Access Journals (Sweden)

Brendan D Cowled

Full Text Available Infectious wildlife diseases have enormous global impacts, leading to human pandemics, global biodiversity declines and socio-economic hardship. Understanding how infection persists and is transmitted in wildlife is critical for managing diseases, but our understanding is limited. Our study aim was to better understand how infectious disease persists in wildlife populations by integrating genetics, ecology and epidemiology approaches. Specifically, we aimed to determine whether environmental or host factors were stronger drivers of Salmonella persistence or transmission within a remote and isolated wild pig (Sus scrofa population. We determined the Salmonella infection status of wild pigs. Salmonella isolates were genotyped and a range of data was collected on putative risk factors for Salmonella transmission. We a priori identified several plausible biological hypotheses for Salmonella prevalence (cross sectional study design versus transmission (molecular case series study design and fit the data to these models. There were 543 wild pig Salmonella observations, sampled at 93 unique locations. Salmonella prevalence was 41% (95% confidence interval [CI]: 37-45%. The median Salmonella DICE coefficient (or Salmonella genetic similarity was 52% (interquartile range [IQR]: 42-62%. Using the traditional cross sectional prevalence study design, the only supported model was based on the hypothesis that abundance of available ecological resources determines Salmonella prevalence in wild pigs. In the molecular study design, spatial proximity and herd membership as well as some individual risk factors (sex, condition score and relative density determined transmission between pigs. Traditional cross sectional surveys and molecular epidemiological approaches are complementary and together can enhance understanding of disease ecology: abundance of ecological resources critical for wildlife influences Salmonella prevalence, whereas Salmonella transmission is

Integrating Survey and Molecular Approaches to Better Understand Wildlife Disease Ecology

Science.gov (United States)

Cowled, Brendan D.; Ward, Michael P.; Laffan, Shawn W.; Galea, Francesca; Garner, M. Graeme; MacDonald, Anna J.; Marsh, Ian; Muellner, Petra; Negus, Katherine; Quasim, Sumaiya; Woolnough, Andrew P.; Sarre, Stephen D.

2012-01-01

Infectious wildlife diseases have enormous global impacts, leading to human pandemics, global biodiversity declines and socio-economic hardship. Understanding how infection persists and is transmitted in wildlife is critical for managing diseases, but our understanding is limited. Our study aim was to better understand how infectious disease persists in wildlife populations by integrating genetics, ecology and epidemiology approaches. Specifically, we aimed to determine whether environmental or host factors were stronger drivers of Salmonella persistence or transmission within a remote and isolated wild pig (Sus scrofa) population. We determined the Salmonella infection status of wild pigs. Salmonella isolates were genotyped and a range of data was collected on putative risk factors for Salmonella transmission. We a priori identified several plausible biological hypotheses for Salmonella prevalence (cross sectional study design) versus transmission (molecular case series study design) and fit the data to these models. There were 543 wild pig Salmonella observations, sampled at 93 unique locations. Salmonella prevalence was 41% (95% confidence interval [CI]: 37–45%). The median Salmonella DICE coefficient (or Salmonella genetic similarity) was 52% (interquartile range [IQR]: 42–62%). Using the traditional cross sectional prevalence study design, the only supported model was based on the hypothesis that abundance of available ecological resources determines Salmonella prevalence in wild pigs. In the molecular study design, spatial proximity and herd membership as well as some individual risk factors (sex, condition score and relative density) determined transmission between pigs. Traditional cross sectional surveys and molecular epidemiological approaches are complementary and together can enhance understanding of disease ecology: abundance of ecological resources critical for wildlife influences Salmonella prevalence, whereas Salmonella transmission is driven by

Energize It! An Ecologically Integrated Approach to the Study of the Digestive System and Energy Acquisition.

Science.gov (United States)

Derting, Terry L.

1992-01-01

Develops a research-oriented method of studying the digestive system that integrates species' ecology with the form and function of this system. Uses problem-posing, problem-probing, and peer persuasion. Presents information for mammalian systems. (27 references) (MKR)

Integrating a DNA barcoding project with an ecological survey: a case study on temperate intertidal polychaete communities in Qingdao, China

Science.gov (United States)

Zhou, Hong; Zhang, Zhinan; Chen, Haiyan; Sun, Renhua; Wang, Hui; Guo, Lei; Pan, Haijian

2010-07-01

In this study, we integrated a DNA barcoding project with an ecological survey on intertidal polychaete communities and investigated the utility of CO1 gene sequence as a DNA barcode for the classification of the intertidal polychaetes. Using 16S rDNA as a complementary marker and combining morphological and ecological characterization, some of dominant and common polychaete species from Chinese coasts were assessed for their taxonomic status. We obtained 22 haplotype gene sequences of 13 taxa, including 10 CO1 sequences and 12 16S rDNA sequences. Based on intra- and inter-specific distances, we built phylogenetic trees using the neighbor-joining method. Our study suggested that the mitochondrial CO1 gene was a valid DNA barcoding marker for species identification in polychaetes, but other genes, such as 16S rDNA, could be used as a complementary genetic marker. For more accurate species identification and effective testing of species hypothesis, DNA barcoding should be incorporated with morphological, ecological, biogeographical, and phylogenetic information. The application of DNA barcoding and molecular identification in the ecological survey on the intertidal polychaete communities demonstrated the feasibility of integrating DNA taxonomy and ecology.

Stable isotopes and diet of hunters gatherers of southwest of Buenos Aires province (Argentina)

International Nuclear Information System (INIS)

Scabuzzo, Clara; Frontini, Romina; Vecchi, Rodrigo; Bayon, Cristina

2016-01-01

Results of the first stable isotopes analysis (δ""1"3C and δ"1"5N) of archaeological sites located in the southwest of the province of Buenos Aires (Argentina) are presented. Both the construction of an isotopic ecology and prehistoric human diets of the sector are explored. The isotopic ecology indicates diverse environments in which marine animals have enriched δ"1"3C col. values; while terrestrial species such as coypo, greater rhea and large-sized herbivores have the poorest values that are indistinguishable among the different taxa. Furthermore, ducks and a hairy armadillo showed intermediate values. Human isotopic values indicate a diet based on the consumption of meat. These proteins came predominantly from terrestrial animals complemented by marine resources. The local archaeological record is consistent with this information, as the main faunal resources are terrestrial species; nevertheless a scarce representation of marine fauna, mainly Otariids, is registered. In this paper we present the first isotopic values for the studied area and thus it is a preliminary contribution that must be further investigated with new samples

Forest Fire Ecology.

Science.gov (United States)

Zucca, Carol; And Others

1995-01-01

Presents a model that integrates high school science with the needs of the local scientific community. Describes how a high school ecology class conducted scientific research in fire ecology that benefited the students and a state park forest ecologist. (MKR)

Possibilities of the Integration of the Method of the Ecologically Oriented Independent Scientific Research in the Study Process

Science.gov (United States)

Grizans, Jurijs; Vanags, Janis

2010-01-01

The aim of this paper is to analyse possibilities of the integration of the method of the ecologically oriented independent scientific research in the study process. In order to achieve the set aim, the following scientific research methods were used: analysis of the conceptual guidelines for the development of environmentally oriented entrepreneurship, interpretation of the experts' evaluation of the ecologically oriented management, analysis of the results of the students' ecologically oriented independent scientific research, as well as monographic and logically constructive methods. The results of the study give an opportunity to make conclusions and to develop conceptual recommendations on how to introduce future economics and business professionals with the theoretical and practical aspects of ecologically oriented management during the study process.

Brayton Isotope Power System, Design Integrity Checklist (BIPS-DIC)

Energy Technology Data Exchange (ETDEWEB)

Miller, L.G.

1976-06-10

A preliminary Failure Modes, Effects and Criticality Analysis (FMECA) for the BIPS Flight System (FS) was published as AiResearch Report 76-311709 dated January 12, 1976. The FMECA presented a thorough review of the conceptual BIPS FS to identify areas of concern and activities necessary to avoid premature failures. In order to assure that the actions recommended by the FMECA are effected in both the FS and the Ground Demonstration System (GDS), a checklist (the BIPS-DIC) was prepared for the probability of occurrence of those failure modes that rated highest in criticality ranking. This checklist was circulated as an attachment to AiResearch Coordination Memo No. BIPS-GDS-A0106 dated January 23, 1976. The Brayton Isotope Power System-Design Integrity Checklist (BIPS-DIC) has been revised and is presented. Additional entries have been added that reference failure modes determined to rank highest in criticality ranking. The checklist will be updated periodically.

Ecology and Education in Landscape Architecture

Directory of Open Access Journals (Sweden)

James Miller

2004-06-01

Full Text Available Landscape architects engage in a wide range of projects relating to environmental quality. Indeed, the goals of preserving biodiversity and maintaining the integrity of ecological function is implicit in the charters of several of the discipline's professional organisations. Nonetheless, there is widespread opinion that much of the potential of design to contribute to environmental solutions goes unrealised. There are numerous explanations that purport to account for this situation; in this paper, we focus on one, the assertion that degree programmes in landscape architecture generally do a poor job of preparing students for practice grounded in ecological awareness. We examined the validity of this assertion by quantifying the amount and form of ecology-based coursework required of landscape architecture students. We surveyed the curricula of all 63 accredited, first-professional degree programmes in North America (28 offering a BLA, 17 offering an MLA and 18 offering both. We focused on required courses that could be categorised as emphasising information-based ecology, ecology/design integration, or plant identification and ecology. We recorded the level (introductory or advanced and number of credit hours for each course, and the total number of credits required for graduation in each programme. Thirty-seven undergraduate programmes required an introductory information-based ecology course. Only 13 required an advanced class in ecology and, of these, only three required coursework in landscape ecology. All of the undergraduate programmes except one required a plant class. Ten of the graduate programmes required an information-based class, an advanced, except one. Six required a course in landscape ecology. Eight required at least one ecology-design integration course, yet had no requirements regarding information-based courses. Thirty graduate programmes required at least one plant course. We discuss the implications of these results and

Integrating chytrid fungal parasites into plankton ecology: research gaps and needs.

Science.gov (United States)

Frenken, Thijs; Alacid, Elisabet; Berger, Stella A; Bourne, Elizabeth C; Gerphagnon, Mélanie; Grossart, Hans-Peter; Gsell, Alena S; Ibelings, Bas W; Kagami, Maiko; Küpper, Frithjof C; Letcher, Peter M; Loyau, Adeline; Miki, Takeshi; Nejstgaard, Jens C; Rasconi, Serena; Reñé, Albert; Rohrlack, Thomas; Rojas-Jimenez, Keilor; Schmeller, Dirk S; Scholz, Bettina; Seto, Kensuke; Sime-Ngando, Télesphore; Sukenik, Assaf; Van de Waal, Dedmer B; Van den Wyngaert, Silke; Van Donk, Ellen; Wolinska, Justyna; Wurzbacher, Christian; Agha, Ramsy

2017-10-01

Chytridiomycota, often referred to as chytrids, can be virulent parasites with the potential to inflict mass mortalities on hosts, causing e.g. changes in phytoplankton size distributions and succession, and the delay or suppression of bloom events. Molecular environmental surveys have revealed an unexpectedly large diversity of chytrids across a wide range of aquatic ecosystems worldwide. As a result, scientific interest towards fungal parasites of phytoplankton has been gaining momentum in the past few years. Yet, we still know little about the ecology of chytrids, their life cycles, phylogeny, host specificity and range. Information on the contribution of chytrids to trophic interactions, as well as co-evolutionary feedbacks of fungal parasitism on host populations is also limited. This paper synthesizes ideas stressing the multifaceted biological relevance of phytoplankton chytridiomycosis, resulting from discussions among an international team of chytrid researchers. It presents our view on the most pressing research needs for promoting the integration of chytrid fungi into aquatic ecology. © 2017 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

IsoBank – Stable isotope ecology in the age of ‘Big Data’

Science.gov (United States)

Stable isotopes ratios provide valuable information to fish biologists working in a diverse range of fields: e.g. ecologists, population biologists and fishery managers. Ecologists take advantage of stable isotope ratios to provide information on the diet and migration history of consumers or when a...

Discrimination factors of carbon and nitrogen stable isotopes in meerkat feces

Directory of Open Access Journals (Sweden)

Shaena Montanari

2017-06-01

Full Text Available Stable isotope analysis of feces can provide a non-invasive method for tracking the dietary habits of nearly any mammalian species. While fecal samples are often collected for macroscopic and genetic study, stable isotope analysis can also be applied to expand the knowledge of species-specific dietary ecology. It is somewhat unclear how digestion changes the isotope ratios of animals’ diets, so more controlled diet studies are needed. To date, most diet-to-feces controlled stable isotope experiments have been performed on herbivores, so in this study I analyzed the carbon and nitrogen stable isotope ratios in the diet and feces of the meerkat (Suricata suricatta, a small omnivorous mammal. The carbon trophic discrimination factor between diet and feces (Δ13Cfeces is calculated to be 0.1 ± 1.5‰, which is not significantly different from zero, and in turn, not different than the dietary input. On the other hand, the nitrogen trophic discrimination factor (Δ15Nfeces is 1.5 ± 1.1‰, which is significantly different from zero, meaning it is different than the average dietary input. Based on data generated in this experiment and a review of the published literature, carbon isotopes of feces characterize diet, while nitrogen isotope ratios of feces are consistently higher than dietary inputs, meaning a discrimination factor needs to be taken into account. The carbon and nitrogen stable isotope values of feces are an excellent snapshot of diet that can be used in concert with other analytical methods to better understand ecology, diets, and habitat use of mammals.

Savannah River Ecology Laboratory, Annual Technical Progress Report of Ecological Research, June 30, 2002

Energy Technology Data Exchange (ETDEWEB)

Paul M. Bertsch, (Director)

2002-06-30

The Savannah River Ecology Laboratory (SREL) is a research unit of The University of Georgia (UGA) and has been conducting ecological research on the Savannah River Site (SRS) near Aiken, South Carolina for 50 years. The overall mission of the Laboratory is to acquire and communicate knowledge of ecological processes and principles. SREL conducts fundamental and applied ecological research, as well as education and outreach programs, under a Cooperative Agreement with the U.S. Department of Energy (DOE). The Laboratory's research mission during the 2002 fiscal year was fulfilled with the publication of 76 journal articles and book chapters by faculty, technical staff, students, and visiting scientists. An additional 50 journal articles have been submitted or are in press. Other noteworthy events took place as faculty members, staff, and graduate students received awards. These are described in the section titled Special Accomplishments of Faculty, Staff, Students, and Administration on page 51. Notable scientific accomplishments include work conducted on contaminant transport, stable isotopes, sandhills ecology, and phytoremediation: (1) A collaborative study between Dr. Tom Hinton at SREL and scientists at SRTC demonstrated the feasibility of using illite clay to sequester 137Cs in sediments along the P and R reactor cooling canal system, where approximately 3,000 acres of land are contaminated. Overall, the study showed significant decreases in cesium concentrations and bioavailability following the addition of illite with no sign of harm to the ecosystem. While the cesium remains sequestered from the biosphere, its radioactivity decays and the process progresses from contaminant immobilization to remediation. (2) SREL's stable isotope laboratory is now fully functional. Stable isotope distributions in nature can provide important insights into many historical and current environmental processes. Dr. Christopher Romanek is leading SREL's research

Savannah River Ecology Laboratory, Annual Technical Progress Report of Ecological Research, June 30, 2002

International Nuclear Information System (INIS)

Paul M. Bertsch,

2002-01-01

The Savannah River Ecology Laboratory (SREL) is a research unit of The University of Georgia (UGA) and has been conducting ecological research on the Savannah River Site (SRS) near Aiken, South Carolina for 50 years. The overall mission of the Laboratory is to acquire and communicate knowledge of ecological processes and principles. SREL conducts fundamental and applied ecological research, as well as education and outreach programs, under a Cooperative Agreement with the U.S. Department of Energy (DOE). The Laboratory's research mission during the 2002 fiscal year was fulfilled with the publication of 76 journal articles and book chapters by faculty, technical staff, students, and visiting scientists. An additional 50 journal articles have been submitted or are in press. Other noteworthy events took place as faculty members, staff, and graduate students received awards. These are described in the section titled Special Accomplishments of Faculty, Staff, Students, and Administration on page 51. Notable scientific accomplishments include work conducted on contaminant transport, stable isotopes, sandhills ecology, and phytoremediation: (1) A collaborative study between Dr. Tom Hinton at SREL and scientists at SRTC demonstrated the feasibility of using illite clay to sequester 137Cs in sediments along the P and R reactor cooling canal system, where approximately 3, 000 acres of land are contaminated. Overall, the study showed significant decreases in cesium concentrations and bioavailability following the addition of illite with no sign of harm to the ecosystem. While the cesium remains sequestered from the biosphere, its radioactivity decays and the process progresses from contaminant immobilization to remediation. (2) SREL's stable isotope laboratory is now fully functional. Stable isotope distributions in nature can provide important insights into many historical and current environmental processes. Dr. Christopher Romanek is leading SREL's research in this area

Global Principle of Ecological Integrity and its Implementation in Management of the Czech Landscape

Czech Academy of Sciences Publication Activity Database

Cudlínová, Eva; Lapka, Miloslav; Líšková, Zuzana

2005-01-01

Roč. 24, č. 1 (2005), s. 89-107 ISSN 1335-342X R&D Projects: GA MŠk(CZ) ME 530; GA MŽP(CZ) SM/640/18/03 Grant - others:EU GOCE-CT-2003-505297-MULTAGRI Institutional research plan: CEZ:AV0Z60870520 Keywords : ecological integrity * landscape * typology * category Subject RIV: AO - Sociology, Demography Impact factor: 0.085, year: 2005

Isotopes in Greenland Precipitation

DEFF Research Database (Denmark)

Faber, Anne-Katrine

Greenland ice cores offer a unique opportunity to investigate the climate system behaviour. The objective of this PhD project is to investigate isotope modelling of present- day conditions and conduct model-data comparison using Greenland ice cores. Thus this thesis investigates how the integration...... of model and data can be used to improve the understanding of climate changes. This is done through analysis of isotope modelling, observations and ice core measurements. This dissertation comprises three projects: (1) Modelling the isotopic response to changes in Arctic sea surface conditions, (2......) Constructing a new Greenland database of observations and present-day ice core measurements, and (3) Performance test of isotope-enabled CAM5 for Greenland. The recent decades of rapid Arctic sea ice decline are used as a basis for an observational-based model experiment using the isotope-enabled CAM model 3...

Development of the Hydrological-Ecological Integrated watershed Flow Model (HEIFLOW): an application to the Heihe River Basin

Science.gov (United States)

Tian, Y.; Zheng, Y.; Zheng, C.; Han, F., Sr.

2017-12-01

Physically based and fully-distributed integrated hydrological models (IHMs) can quantitatively depict hydrological processes, both surface and subsurface, with sufficient spatial and temporal details. However, the complexity involved in pre-processing data and setting up models seriously hindered the wider application of IHMs in scientific research and management practice. This study introduces our design and development of Visual HEIFLOW, hereafter referred to as VHF, a comprehensive graphical data processing and modeling system for integrated hydrological simulation. The current version of VHF has been structured to accommodate an IHM named HEIFLOW (Hydrological-Ecological Integrated watershed-scale FLOW model). HEIFLOW is a model being developed by the authors, which has all typical elements of physically based and fully-distributed IHMs. It is based on GSFLOW, a representative integrated surface water-groundwater model developed by USGS. HEIFLOW provides several ecological modules that enable to simulate growth cycle of general vegetation and special plants (maize and populus euphratica). VHF incorporates and streamlines all key steps of the integrated modeling, and accommodates all types of GIS data necessary to hydrological simulation. It provides a GIS-based data processing framework to prepare an IHM for simulations, and has functionalities to flexibly display and modify model features (e.g., model grids, streams, boundary conditions, observational sites, etc.) and their associated data. It enables visualization and various spatio-temporal analyses of all model inputs and outputs at different scales (i.e., computing unit, sub-basin, basin, or user-defined spatial extent). The above system features, as well as many others, can significantly reduce the difficulty and time cost of building and using a complex IHM. The case study in the Heihe River Basin demonstrated the applicability of VHF for large scale integrated SW-GW modeling. Visualization and spatial

Expanding the isotopic toolbox: Applications of hydrogen and oxygen stable isotope ratios to food web studies

Directory of Open Access Journals (Sweden)

Hannah B Vander Zanden

2016-03-01

Full Text Available The measurement of stable carbon (δ13C and nitrogen (δ15N isotopes in tissues of organisms has formed the foundation of isotopic food web reconstructions, as these values directly reflect assimilated diet. In contrast, stable hydrogen (δ2H and oxygen (δ18O isotope measurements have typically been reserved for studies of migratory origin and paleoclimate reconstruction based on systematic relationships between organismal tissue and local environmental water. Recently, innovative applications using δ2H and, to a lesser extent, δ18O values have demonstrated potential for these elements to provide novel insights in modern food web studies. We explore the advantages and challenges associated with three applications of δ2H and δ18O values in food web studies. First, large δ2H differences between aquatic and terrestrial ecosystem end members can permit the quantification of energy inputs and nutrient fluxes between these two sources, with potential applications for determining allochthonous vs. autochthonous nutrient sources in freshwater systems and relative aquatic habitat utilization by terrestrial organisms. Next, some studies have identified a relationship between δ2H values and trophic position, which suggests that this marker may serve as a trophic indicator, in addition to the more commonly used δ15N values. Finally, coupled measurements of δ2H and δ18O values are increasing as a result of reduced analytical challenges to measure both simultaneously and may provide additional ecological information over single element measurements. In some organisms, the isotopic ratios of these two elements are tightly coupled, whereas the isotopic disequilibrium in other organisms may offer insight into the diet and physiology of individuals. Although a coherent framework for interpreting δ2H and δ18O data in the context of food web studies is emerging, many fundamental uncertainties remain. We highlight directions for targeted research that

Using 2H and 18O in assessing evaporation and water residence time of lakes in EPA’s National Lakes Assessment.

Science.gov (United States)

Stable isotopes of water and organic material can be very useful in monitoring programs because stable isotopes integrate information about ecological processes and record this information. Most ecological processes of interest for water quality (i.e. denitrification) require si...

Manual for prototyping integrated and ecological arable farming systems (I/EAFS) in interaction with pilot farms

NARCIS (Netherlands)

Vereijken, P.

1999-01-01

A manual for prototyping Integrated and Ecological Arable Farming Systems (I/EAFS) in interaction with pilot farms is presented. It concerns a comprehensive and consistent approach of 5 steps. Step 1 is establishing a hierarchy of objectives considering the shortcomings of current farming systems in

Laser Spectroscopic Analysis of Liquid Water Samples for Stable Hydrogen and Oxygen Isotopes

International Nuclear Information System (INIS)

2009-01-01

Stable isotope ratios of hydrogen and oxygen are tracers of choice for water cycle processes in hydrological, atmospheric and ecological studies. The use of isotopes has been limited to some extent because of the relatively high cost of isotope ratio mass spectrometers and the need for specialized operational skills. Here, the results of performance testing of a recently developed laser spectroscopic instrument for measuring stable hydrogen and oxygen isotope ratios of water samples are described, along with a procedure for instrument installation and operation. Over the last four years, the IAEA Water Resources Programme conducted prototype and production model testing of these instruments and this publication is the outcome of those efforts. One of the main missions of the IAEA is to promote the use of peaceful applications of isotope and nuclear methods in Member States and this publication is intended to facilitate the use of laser absorption based instruments for hydrogen and oxygen stable isotope analyses of liquid water samples for hydrological and other studies. The instrument uses off-axis integrated cavity output spectroscopy to measure absolute abundances of 2 HHO, HH 18 O, and HHO via laser absorption. Test results using a number of natural and synthetic water standards and samples with a large range of isotope values demonstrate adequate precision and accuracy (e.g. precisions of 1 per mille for δ 2 H and 0.2 per mille for δ 18 O). The laser instrument has much lower initial and maintenance costs than mass spectrometers and is substantially easier to operate. Thus, these instruments have the potential to bring about a paradigm shift in isotope applications by enabling researchers in all fields to measure isotope ratios by themselves. The appendix contains a detailed procedure for the installation and operation of the instrument. Using the procedure, new users should be able to install the instrument in less than two hours. It also provides step

Performance evaluation of nitrogen isotope ratio determination in marine and lacustrine sediments: An inter-laboratory comparison

NARCIS (Netherlands)

Bahlmann, E.; Bernasconi, S.M.; Bouillon, S.; Houtekamer, M.J.; Korntheuer, M.; Langenberg, F.; Mayr, C.; Metzke, M.; Middelburg, J.J.; Nagel, B.; Struck, U.; Voß, M.; Emeis, K.C.

2010-01-01

Nitrogen isotopes of organic matter are increasingly studied in marine biogeochemistry and geology, plant and animal ecology, and paleoceanography. Here, we present results of an inter-laboratory test on determination of nitrogen isotope ratios in marine and lacustrine sediments. Six different

Ecological economics of North American integration: the reshaping of the economic landscape in the Santiago river basin

Directory of Open Access Journals (Sweden)

Salvador Peniche Camps

2017-06-01

Full Text Available Ecological Economics studies social metabolism; that is, the material and energy flow into and out of the economy. Using the ecological economics perspective, we analyse the transformation of the economic landscape of the Santiago river basin, Mexico. We discuss why the appropriation of water resources is one of the most important drivers of North American economic integration. We argue that the theoretical model of neo-extractivism can explain the dynamics of social metabolism behind the North American Free Trade Agreement (NAFTA.

Landscape Ecology

DEFF Research Database (Denmark)

Christensen, Andreas Aagaard; Brandt, Jesper; Svenningsen, Stig Roar

2017-01-01

, and the ecological significance of the patterns which are generated by such processes. In landscape ecology, perspectives drawn from existing academic disciplines are integrated based on a common, spatially explicit mode of analysis developed from classical holistic geography, emphasizing spatial and landscape...... to translate positivist readings of the environment and hermeneutical perspectives on socioecological interaction into a common framework or terminology....

Science and Ecological Economics: Integrating of the Study of Humans and the Rest of Nature

Science.gov (United States)

Costanza, Robert

2009-01-01

Ecological economics is a transdisciplinary field that seeks to integrate the study of humans and the rest of nature as the basis for the creation of a sustainable and desirable future. It seeks to dissolve the barriers between the traditional disciplines and achieve a true "consilience" of all the sciences and humanities. This consilient,…

Integration of ecological-biological thresholds in conservation decision making.

Science.gov (United States)

Mavrommati, Georgia; Bithas, Kostas; Borsuk, Mark E; Howarth, Richard B

2016-12-01

In the Anthropocene, coupled human and natural systems dominate and only a few natural systems remain relatively unaffected by human influence. On the one hand, conservation criteria based on areas of minimal human impact are not relevant to much of the biosphere. On the other hand, conservation criteria based on economic factors are problematic with respect to their ability to arrive at operational indicators of well-being that can be applied in practice over multiple generations. Coupled human and natural systems are subject to economic development which, under current management structures, tends to affect natural systems and cross planetary boundaries. Hence, designing and applying conservation criteria applicable in real-world systems where human and natural systems need to interact and sustainably coexist is essential. By recognizing the criticality of satisfying basic needs as well as the great uncertainty over the needs and preferences of future generations, we sought to incorporate conservation criteria based on minimal human impact into economic evaluation. These criteria require the conservation of environmental conditions such that the opportunity for intergenerational welfare optimization is maintained. Toward this end, we propose the integration of ecological-biological thresholds into decision making and use as an example the planetary-boundaries approach. Both conservation scientists and economists must be involved in defining operational ecological-biological thresholds that can be incorporated into economic thinking and reflect the objectives of conservation, sustainability, and intergenerational welfare optimization. © 2016 Society for Conservation Biology.

Landfill mining in Austria: foundations for an integrated ecological and economic assessment.

Science.gov (United States)

Hermann, Robert; Baumgartner, Rupert J; Sarc, Renato; Ragossnig, Arne; Wolfsberger, Tanja; Eisenberger, Martin; Budischowsky, Andreas; Pomberger, Roland

2014-09-01

For the first time, basic technical and economic studies for landfill mining are being carried out in Austria on the basis of a pilot project. An important goal of these studies is the collection of elementary data as the basis for an integrated ecological and economic assessment of landfill mining projects with regard to their feasibility. For this purpose, economic, ecological, technical, organizational, as well as political and legal influencing factors are identified and extensively studied in the article. An important aspect is the mutual influence of the factors on each other, as this can significantly affect the development of an integrated assessment system. In addition to the influencing factors, the definition of the spatial and temporal system boundaries is crucial for further investigations. Among others, the quality and quantity of recovered waste materials, temporal fluctuations or developments in prices of secondary raw material and fuels attainable in the markets, and time and duration of dumping, play a crucial role. Based on the investigations, the spatial system boundary is defined in as much as all the necessary process steps, from landfill mining, preparing and sorting to providing a marketable material/product by the landfill operator, are taken into account. No general accepted definition can be made for the temporal system boundary because the different time-related influencing factors necessitate an individual project-specific determination and adaptation to the facts of the on-site landfill mining project. © The Author(s) 2014.

Controls of Isotopic Patterns in Saprotrophic and Ectomycorrhizal Fungi

Science.gov (United States)

Isotopes of nitrogen (δ15N) and carbon (δ13C) in ectomycorrhizal and saprotrophic fungi contain important information about ecological functioning, but the complexity of physiological and ecosystem processes contributing to fungal carbon and nitrogen dynamics has limited our abil...

Diet-tissue stable isotope (Δ¹³C and Δ¹⁵N) discrimination factors for multiple tissues from terrestrial reptiles

OpenAIRE

Steinitz, R; Lemm, JM; Pasachnik, SA; Kurle, CM

2016-01-01

Copyright © 2015 John Wiley & Sons, Ltd. Rationale Stable isotope analysis is a powerful tool for reconstructing trophic interactions to better understand drivers of community ecology. Taxon-specific stable isotope discrimination factors contribute to the best use of this tool. We determined the first Δ 13 C and Δ 15 N values for Rock Iguanas (Cyclura spp.) to better understand isotopic fractionation and estimate wild reptile foraging ecology. Methods The Δ 13 C and Δ 15 N values between di...

[Ecological misunderstanding, integrative approach, and potential industries in circular economy transition].

Science.gov (United States)

Wang, Rusong

2005-12-01

Based on the Social-Economic-Natural Complex Ecosystem theory, this paper questioned 8 kinds of misunderstandings in current planning, incubation, development, and management of circular economy, which had led to either ultra-right or ultra-left actions in ecological and economic development. Rather than concentrated only on the 3-r micro-principles of "reduce-reuse-recycle", thise paper suggested 3-R macro-principles of "Rethinking-Reform-Refunction" for circular economy development. Nine kinds of eco-integrative strategies in industrial transition were put forward, i.e., food web-based horizontal/parallel coupling, life cycle-oriented vertical/serial coupling, functional service rather than products-oriented production, flexible and adaptive structure, ecosystem-based regional coupling, social integrity, comprehensive capacity building, employment enhancement, and respecting human dignity. Ten promising potential eco-industries in China's near-future circular economy development were proposed, such as the transition of traditional chemical fertilizer and pesticide industry to a new kind of industrial complex for agro-ecosystem management.

Spectral contaminant identifier for off-axis integrated cavity output spectroscopy measurements of liquid water isotopes

Energy Technology Data Exchange (ETDEWEB)

Brian Leen, J.; Berman, Elena S. F.; Gupta, Manish [Los Gatos Research, 67 East Evelyn Avenue, Suite 3, Mountain View, California 94041-1518 (United States); Liebson, Lindsay [Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States)

2012-04-15

Developments in cavity-enhanced absorption spectrometry have made it possible to measure water isotopes using faster, more cost-effective field-deployable instrumentation. Several groups have attempted to extend this technology to measure water extracted from plants and found that other extracted organics absorb light at frequencies similar to that absorbed by the water isotopomers, leading to {delta}{sup 2}H and {delta}{sup 18}O measurement errors ({Delta}{delta}{sup 2}H and {Delta}{delta}{sup 18}O). In this note, the off-axis integrated cavity output spectroscopy (ICOS) spectra of stable isotopes in liquid water is analyzed to determine the presence of interfering absorbers that lead to erroneous isotope measurements. The baseline offset of the spectra is used to calculate a broadband spectral metric, m{sub BB}, and the mean subtracted fit residuals in two regions of interest are used to determine a narrowband metric, m{sub NB}. These metrics are used to correct for {Delta}{delta}{sup 2}H and {Delta}{delta}{sup 18}O. The method was tested on 14 instruments and {Delta}{delta}{sup 18}O was found to scale linearly with contaminant concentration for both narrowband (e.g., methanol) and broadband (e.g., ethanol) absorbers, while {Delta}{delta}{sup 2}H scaled linearly with narrowband and as a polynomial with broadband absorbers. Additionally, the isotope errors scaled logarithmically with m{sub NB}. Using the isotope error versus m{sub NB} and m{sub BB} curves, {Delta}{delta}{sup 2}H and {Delta}{delta}{sup 18}O resulting from methanol contamination were corrected to a maximum mean absolute error of 0.93 per mille and 0.25 per mille respectively, while {Delta}{delta}{sup 2}H and {Delta}{delta}{sup 18}O from ethanol contamination were corrected to a maximum mean absolute error of 1.22 per mille and 0.22 per mille . Large variation between instruments indicates that the sensitivities must be calibrated for each individual isotope analyzer. These results suggest that the

Recent progress in ecological studies of soil fauna

NARCIS (Netherlands)

Hasegawa, Motohiro; Fujii, Saori; Kaneda, Satoshi; Ikeda, Hiroshi; Hishi, Takuo; Hyodo, Fujio; Kobayashi, Makoto

2017-01-01

Progress in ecological studies of soil fauna includes studies of the role and effects of soil fauna on decomposition and soil carbon dynamics in relation to global environmental changes, the introduction of molecular biology approaches to such studies, feeding habit analysis using stable isotopes,

Ecological and Biogeochemical Impacts of Internal Waves on Mesophotic Coral Ecosystems: Testing Eddy Covariance and Isotope Approaches, Iriomote, Japan

Science.gov (United States)

Wyatt, A. S. J.; Miyajima, T.; Leichter, J.; Naruse, T.; Kuwae, T.; Yamamoto, S.; Satoh, N.; Nagata, T.

2016-02-01

Mesophotic coral ecosystems (MCE) occur in the `twilight zone' of decreasing light between 30 - 150 m water depth where they may be protected or damped from disturbances impacting shallower reefs. However insufficient information is available on the environmental conditions that support MCE to allow us to understand and conserve these `deep water refugia'. For instance, nutrient inputs and recycling have rarely been quantified over MCE, but deeper reefs may differ fundamentally to that of shallow counterparts due to the reduction in light and increasing use of oceanic nutrients at the base of the food web, leading to increased reliance on heterotrophy over autotrophy at species and ecosystem levels and stronger links to oceanic processes. For instance, due to their depth relative to typical water column density stratification, MCE are particularly likely to experience internal wave forcing, the significance of which should vary spatially depending on aspect and exposure. In this study we are focusing on MCE occurring along a continuum of oceanic-exposure along Funauki Bay on the west coast of Iriomote, Japan. Here our preliminary observations indicate that ocean-exposed MCE are subject to semi-diurnal temperature oscillations of up to 4 C during summer (range 23 - 29 deg C), while inner bay MCE occur at shallower depths in more turbid but stable environments. This continuum of oceanic exposure is ideal for testing a range of approaches for quantifying the relative ecological and biogeochemical influence of internal waves. Stable isotope analyses (SIA) are a particularly useful tool for understanding functional links between oceanic processes, local-scale nutrient cycling, and trophic ecology, with results from shallow reefs showing they likely function along a continuum of reliance on external inputs versus internal recycling depending on the degree of oceanic exposure. Although challenging to implement in deep water habitats, the combination of SIA with compound

Isotope incorporation in broad-snouted caimans (crocodilians

Directory of Open Access Journals (Sweden)

Stephane Caut

2013-05-01

The trophic ecology and migration of vertebrate species have been increasingly studied using stable isotope analysis. However, this approach requires knowledge on how dietary isotopic values are reflected in consumers' tissues. To date, this information has only been obtained for a handful of ectotherms; in particular, little is known about crocodilians. In this study, diet-tissue discrimination factors (DTDFs and carbon and nitrogen stable isotope turnover rates were estimated for plasma, red blood cells (RBCs, and muscle obtained from broad-snouted caimans (Caiman latirostris. Individuals were fed two different control diets for 189 days. DTDFs for δ15N (Δ15N and δ13C (Δ13C ranged from −2.24‰ to 0.39‰ and from −0.52‰ to 1.06‰, respectively. Isotope turnover rates in tissues, expressed as half-lives, ranged from 11 to 71 days, with plasmaisotope incorporation data should help inform future interpretations of isotopic values obtained in the field for this taxon.

Ecological and spatial factors drive intra- and interspecific variation in exposure of subarctic predatory bird nestlings to persistent organic pollutants.

Science.gov (United States)

Eulaers, Igor; Jaspers, Veerle L B; Bustnes, Jan O; Covaci, Adrian; Johnsen, Trond V; Halley, Duncan J; Moum, Truls; Ims, Rolf A; Hanssen, Sveinn A; Erikstad, Kjell E; Herzke, Dorte; Sonne, Christian; Ballesteros, Manuel; Pinxten, Rianne; Eens, Marcel

2013-07-01

Top predators in northern ecosystems may suffer from exposure to persistent organic pollutants (POPs) as this exposure may synergistically interact with already elevated natural stress in these ecosystems. In the present study, we aimed at identifying biological (sex, body condition), ecological (dietary carbon source, trophic level) and spatial factors (local habitat, regional nest location) that may influence intra- and interspecific variation in exposure of subarctic predatory bird nestlings to polychlorinated biphenyl 153 (CB 153), polybrominated diphenyl ether 47 (BDE 47), dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorobenzene (HCB). During three breeding seasons (2008-2010), we sampled body feathers from fully-grown nestlings of three ecologically distinct predatory bird species in subarctic Norway: Northern Goshawk (Accipiter gentilis), White-tailed Eagle (Haliaeetus albicilla) and Golden Eagle (Aquila chrysaetos). The present study analysed, for the first time, body feathers for both POPs and carbon (δ(13)C) and nitrogen (δ(15)N) stable isotopes, thus integrating the dietary carbon source, trophic level and POP exposure for the larger part of the nestling stage. Intraspecific variation in exposure was driven by a combination of ecological and spatial factors, often different for individual compounds. In addition, combinations for individual compounds differed among species. Trophic level and local habitat were the predominant predictors for CB 153, p,p'-DDE and BDE 47, indicating their biomagnification and decreasing levels according to coast>fjord>inland. Variation in exposure may also have been driven by inter-annual variation arisen from primary sources (e.g. p,p'-DDE) and/or possible revolatilisation from secondary sources (e.g. HCB). Interspecific differences in POP exposure were best explained by a combination of trophic level (biomagnification), dietary carbon source (food chain discrimination) and regional nest location (historical POP

Ecological modernization of sustainable buildings

DEFF Research Database (Denmark)

Jensen, Jesper Ole; Gram-Hanssen, Kirsten

2008-01-01

This article will examine how the contemporary development of sustainable buildings has been influenced by the concept of ecological modernisation. Ecological modernisation is a policy concept describing how environmental considerations are increasingly being integrated into modern society...... driven by enthusiasts and grassroots to being a more widespread, generally obtainable and integrated product. We will discuss to what degree this can be understood within the ideas of ecological modernisation, and then discuss the benefits and drawbacks of this development. Based on the concepts...... of governance, standardisation and visibility, the conclusion is that in many ways ecological modernisation has penetrated in Danish sustainable buildings and has contributed to a positive development. However, there are aspects of sustainable consumption that this development does not relate to, including...

Integrated models to support multiobjective ecological restoration decisions.

Science.gov (United States)

Fraser, Hannah; Rumpff, Libby; Yen, Jian D L; Robinson, Doug; Wintle, Brendan A

2017-12-01

Many objectives motivate ecological restoration, including improving vegetation condition, increasing the range and abundance of threatened species, and improving species richness and diversity. Although models have been used to examine the outcomes of ecological restoration, few researchers have attempted to develop models to account for multiple, potentially competing objectives. We developed a combined state-and-transition, species-distribution model to predict the effects of restoration actions on vegetation condition and extent, bird diversity, and the distribution of several bird species in southeastern Australian woodlands. The actions reflected several management objectives. We then validated the models against an independent data set and investigated how the best management decision might change when objectives were valued differently. We also used model results to identify effective restoration options for vegetation and bird species under a constrained budget. In the examples we evaluated, no one action (improving vegetation condition and extent, increasing bird diversity, or increasing the probability of occurrence for threatened species) provided the best outcome across all objectives. In agricultural lands, the optimal management actions for promoting the occurrence of the Brown Treecreeper (Climacteris picumnus), an iconic threatened species, resulted in little improvement in the extent of the vegetation and a high probability of decreased vegetation condition. This result highlights that the best management action in any situation depends on how much the different objectives are valued. In our example scenario, no management or weed control were most likely to be the best management options to satisfy multiple restoration objectives. Our approach to exploring trade-offs in management outcomes through integrated modeling and structured decision-support approaches has wide application for situations in which trade-offs exist between competing

Human Impacts on Seals, Sea Lions, and Sea Otters: Integrating Archaeology and Ecology of the Northeast Pacific

Directory of Open Access Journals (Sweden)

Ray Pierotti

2013-03-01

Full Text Available Review of Human Impacts on Seals, Sea Lions, and Sea Otters: Integrating Archaeology and Ecology of the Northeast Pacific. Todd J. Braje and Torben C. Rick, editors. 2011. University of California Press, Berkeley. Pp. 328. $65.00 (hardcover. ISBN 9780520267268.

Ecological Vulnerability Assessment Integrating the Spatial Analysis Technology with Algorithms: A Case of the Wood-Grass Ecotone of Northeast China

Directory of Open Access Journals (Sweden)

Zhi Qiao

2013-01-01

Full Text Available This study evaluates ecological vulnerability of the wood-grass ecotone of northeast China integrating the spatial analysis technology with algorithms. An assessment model of ecological vulnerability is developed applying the Analytical Hierarchy Process. The composite evaluation index system is established on the basis of the analysis of contemporary status and potential problems in the study area. By the application of the evaluation model, ecological vulnerability index is calculated between 1990 and 2005. The results show that ecological vulnerability was mostly at a medium level in the study area, however the ecological quality was deteriorating. Through the standard deviational ellipse, the variation of ecological vulnerability can be spatially explicated. It is extremely significative for the prediction of the regions that will easily deteriorate. The deterioration zone was concentrating in the area of Da Hinggan Ling Mountain, including Xingan League, Chifeng, Tongliao, and Chengde, whereas the improvement zone was distributing in the north-central of Hulunbeier.

On the trophic ecology of Gammaridea (Crustacea: Amphipoda) in coastal waters: A European-scale analysis of stable isotopes data

Science.gov (United States)

Mancinelli, Giorgio

2012-12-01

Gammaridean amphipods are found throughout a diverse range of coastal and brackish environments and are generally considered macrophagous herbivores/detritivores. While predation and cannibalism have been shown to be common in freshwater species, motivating a revision of the group functional role, only qualitative information is available on marine Gammaridea. In this study, a survey was conducted of the available literature on stable C and N isotopic signatures of macrophagous, fully aquatic Gammaridea and their potential basal resources in European brackish and coastal environments. The contribution of intra- and inter-specific predation to the signatures of gammarideans was verified by a mixing model procedure where the diet-tissue enrichment constant was not set a priori. Specifically, for each study included in the survey the minimum and maximum diet-tissue nitrogen enrichment factors (Δ15Nmin and Δ15Nmax) providing a non-zero solution were calculated for a range of carbon enrichment factors, assuming that both metrics would increasingly differ from the values expected for a single trophic level as predation and/or cannibalism increased in the diet of the consumer. The minimum enrichment factors Δ15Nmin estimated for a Δ13C of -2.6‰ and +0.5‰ were found to be independent from resource-related artefacts and provided the highest number of successful model runs. Δ15Nmin values were consistent with a diet based on living or decaying primary producers and not compatible with cannibalism or intra-guild predation. However, they showed a bimodal distribution and were on average far below the range found in the literature, matching the enrichment factors of gammarideans measured under laboratory conditions. These results are discussed considering the interaction of the distinctive isotopic features of basal resources in coastal habitats and the biology and ecology of gammaridean amphipods. Particular emphasis is placed on the high variability of nitrogen

[Regional ecological planning and ecological network construction: a case study of "Ji Triangle" Region].

Science.gov (United States)

Li, Bo; Han, Zeng-Lin; Tong, Lian-Jun

2009-05-01

By the methods of in situ investigation and regional ecological planning, the present ecological environment, ecosystem vulnerability, and ecological environment sensitivity in "Ji Triangle" Region were analyzed, and the ecological network of the study area was constructed. According to the ecological resources abundance degree, ecological recovery, farmland windbreak system, environmental carrying capacity, forestry foundation, and ecosystem integrity, the study area was classified into three regional ecological function ecosystems, i. e., east low hill ecosystem, middle plain ecosystem, and west plain wetland ecosystem. On the basis of marking regional ecological nodes, the regional ecological corridor (Haerbin-Dalian regional axis, Changchun-Jilin, Changchun-Songyuan, Jilin-Songyuan, Jilin-Siping, and Songyuan-Siping transportation corridor) and regional ecological network (one ring, three links, and three belts) were constructed. Taking the requests of regional ecological security into consideration, the ecological environment security system of "Ji Triangle" Region, including regional ecological conservation district, regional ecological restored district, and regional ecological management district, was built.

Isotopic determination of the trophic ecology of a ubiquitous key species - The crab Liocarcinus depurator (Brachyura: Portunidae)

Science.gov (United States)

Careddu, Giulio; Calizza, Edoardo; Costantini, Maria Letizia; Rossi, Loreto

2017-05-01

Knowledge of the trophic ecology of predators is key to understanding how they affect food web structure and ecosystem functioning. The harbour crab Liocarcinus depurator (L.) (Brachyura: Portunidae) is one of the most abundant decapod species in soft-bottom areas of the Mediterranean Sea and northeast Atlantic Ocean. It is both a common prey and predator of commercial and non-commercial marine species and its predation pressure appears to have little effect on the subtidal community assemblage. However, there are few studies of its diet and little is known about its role in mediating energy flows in marine ecosystems. In this study, carbon (δ13C) and nitrogen (δ15N) stable isotope analysis (SIA) and Bayesian analytical tools were used to characterise the trophic niche of L. depurator and to quantify the most important prey supporting this species under various environmental conditions. Specimens of L. depurator, their potential prey and basal resources were collected from two different subtidal areas of the Gulf of Gaeta, one affected by human activities (north side) and the other seasonally influenced by freshwater inputs originating from the River Garigliano (south side). While there were differences between the two sampling areas in terms of the abundance and δ15N and δ13C values of the macrobenthic prey community, no differences in the δ15N values and trophic position of L. depurator were observed. Specifically, Bayesian mixing models showed Polychaeta Errantia as the main source of crab diets in both areas. The observed differences in the δ13C values and the analysis of trophic pathways also indicate that the terrestrial organic matter originating from the discharge of the River Garigliano was integrated along the food web up to L. depurator. Although this species is usually considered an opportunistic feeder, it appears to be highly selective and its trophic habits did not influence food web topology, which in contrast was found to be strongly

Development and assessment of an integrated ecological modelling framework to assess the effect of investments in wastewater treatment on water quality.

Science.gov (United States)

Holguin-Gonzalez, Javier E; Boets, Pieter; Everaert, Gert; Pauwels, Ine S; Lock, Koen; Gobeyn, Sacha; Benedetti, Lorenzo; Amerlinck, Youri; Nopens, Ingmar; Goethals, Peter L M

2014-01-01

Worldwide, large investments in wastewater treatment are made to improve water quality. However, the impacts of these investments on river water quality are often not quantified. To assess water quality, the European Water Framework Directive (WFD) requires an integrated approach. The aim of this study was to develop an integrated ecological modelling framework for the River Drava (Croatia) that includes physical-chemical and hydromorphological characteristics as well as the ecological river water quality status. The developed submodels and the integrated model showed accurate predictions when comparing the modelled results to the observations. Dissolved oxygen and nitrogen concentrations (ammonium and organic nitrogen) were the most important variables in determining the ecological water quality (EWQ). The result of three potential investment scenarios of the wastewater treatment infrastructure in the city of Varaždin on the EWQ of the River Drava was assessed. From this scenario-based analysis, it was concluded that upgrading the existing wastewater treatment plant with nitrogen and phosphorus removal will be insufficient to reach a good EWQ. Therefore, other point and diffuse pollution sources in the area should also be monitored and remediated to meet the European WFD standards.

National parks, ecological integrity and climatic change

International Nuclear Information System (INIS)

Lopoukhine, N.

1990-01-01

The potential impacts of climate change on the national parks of Canada are discussed. There is a requirement to protect and manage national parks to maintain a functioning ecosystem with all its parts and processes. An active management regime is necessary, with objectives of ecological diversity/integrity clearly stated. The national parks located in the Canadian Prairie provinces are on or near transitions from forest to tundra and grasslands, and are likely to exhibit the most dramatic changes. The change in vegetation of such parks and in others will not manifest itself simply as a shift of zones but will be accompanied by a flora with new dominants. The boreal forest within the Prairie provinces is fire dependent and has the potential of being transformed into remnant units should post-fire germination be hampered by climatic change. A rapid change in climate would render national parks unable to provide protection of representative elements of Canada's landscapes as presently known. A threefold increase in the area dedicated to protection is a basic component of the sustainable development prescription. All government and private lands dedicated to protection should be forged into a network, to provide core protection for immigrating and emigrating communities and individual species displaced by a changing climate. 20 refs., 2 figs

Comparative feeding ecology of bull sharks (Carcharhinus leucas in the coastal waters of the southwest Indian Ocean inferred from stable isotope analysis.

Directory of Open Access Journals (Sweden)

Ryan Daly

Full Text Available As apex predators, sharks play an important role shaping their respective marine communities through predation and associated risk effects. Understanding the predatory dynamics of sharks within communities is, therefore, necessary to establish effective ecologically based conservation strategies. We employed non-lethal sampling methods to investigate the feeding ecology of bull sharks (Carcharhinus leucas using stable isotope analysis within a subtropical marine community in the southwest Indian Ocean. The main objectives of this study were to investigate and compare the predatory role that sub-adult and adult bull sharks play within a top predatory teleost fish community. Bull sharks had significantly broader niche widths compared to top predatory teleost assemblages with a wide and relatively enriched range of δ(13C values relative to the local marine community. This suggests that bull sharks forage from a more diverse range of δ(13C sources over a wider geographical range than the predatory teleost community. Adult bull sharks appeared to exhibit a shift towards consistently higher trophic level prey from an expanded foraging range compared to sub-adults, possibly due to increased mobility linked with size. Although predatory teleost fish are also capable of substantial migrations, bull sharks may have the ability to exploit a more diverse range of habitats and appeared to prey on a wider diversity of larger prey. This suggests that bull sharks play an important predatory role within their respective marine communities and adult sharks in particular may shape and link ecological processes of a variety of marine communities over a broad range.

Comparative feeding ecology of bull sharks (Carcharhinus leucas) in the coastal waters of the southwest Indian Ocean inferred from stable isotope analysis.

Science.gov (United States)

Daly, Ryan; Froneman, Pierre W; Smale, Malcolm J

2013-01-01

As apex predators, sharks play an important role shaping their respective marine communities through predation and associated risk effects. Understanding the predatory dynamics of sharks within communities is, therefore, necessary to establish effective ecologically based conservation strategies. We employed non-lethal sampling methods to investigate the feeding ecology of bull sharks (Carcharhinus leucas) using stable isotope analysis within a subtropical marine community in the southwest Indian Ocean. The main objectives of this study were to investigate and compare the predatory role that sub-adult and adult bull sharks play within a top predatory teleost fish community. Bull sharks had significantly broader niche widths compared to top predatory teleost assemblages with a wide and relatively enriched range of δ(13)C values relative to the local marine community. This suggests that bull sharks forage from a more diverse range of δ(13)C sources over a wider geographical range than the predatory teleost community. Adult bull sharks appeared to exhibit a shift towards consistently higher trophic level prey from an expanded foraging range compared to sub-adults, possibly due to increased mobility linked with size. Although predatory teleost fish are also capable of substantial migrations, bull sharks may have the ability to exploit a more diverse range of habitats and appeared to prey on a wider diversity of larger prey. This suggests that bull sharks play an important predatory role within their respective marine communities and adult sharks in particular may shape and link ecological processes of a variety of marine communities over a broad range.

Determining origin in a migratory marine vertebrate: a novel method to integrate stable isotopes and satellite tracking

Science.gov (United States)

Vander Zanden, Hannah B.; Tucker, Anton D.; Hart, Kristen M.; Lamont, Margaret M.; Fujisaki, Ikuko; Addison, David S.; Mansfield, Katherine L.; Phillips, Katrina F.; Wunder, Michael B.; Bowen, Gabriel J.; Pajuelo, Mariela; Bolten, Alan B.; Bjorndal, Karen A.

2015-01-01

Stable isotope analysis is a useful tool to track animal movements in both terrestrial and marine environments. These intrinsic markers are assimilated through the diet and may exhibit spatial gradients as a result of biogeochemical processes at the base of the food web. In the marine environment, maps to predict the spatial distribution of stable isotopes are limited, and thus determining geographic origin has been reliant upon integrating satellite telemetry and stable isotope data. Migratory sea turtles regularly move between foraging and reproductive areas. Whereas most nesting populations can be easily accessed and regularly monitored, little is known about the demographic trends in foraging populations. The purpose of the present study was to examine migration patterns of loggerhead nesting aggregations in the Gulf of Mexico (GoM), where sea turtles have been historically understudied. Two methods of geographic assignment using stable isotope values in known-origin samples from satellite telemetry were compared: 1) a nominal approach through discriminant analysis and 2) a novel continuous-surface approach using bivariate carbon and nitrogen isoscapes (isotopic landscapes) developed for this study. Tissue samples for stable isotope analysis were obtained from 60 satellite-tracked individuals at five nesting beaches within the GoM. Both methodological approaches for assignment resulted in high accuracy of foraging area determination, though each has advantages and disadvantages. The nominal approach is more appropriate when defined boundaries are necessary, but up to 42% of the individuals could not be considered in this approach. All individuals can be included in the continuous-surface approach, and individual results can be aggregated to identify geographic hotspots of foraging area use, though the accuracy rate was lower than nominal assignment. The methodological validation provides a foundation for future sea turtle studies in the region to inexpensively

DNA-, RNA-, and Protein-Based Stable-Isotope Probing for High-Throughput Biomarker Analysis of Active Microorganisms.

Science.gov (United States)

Jameson, Eleanor; Taubert, Martin; Coyotzi, Sara; Chen, Yin; Eyice, Özge; Schäfer, Hendrik; Murrell, J Colin; Neufeld, Josh D; Dumont, Marc G

2017-01-01

Stable-isotope probing (SIP) enables researchers to target active populations within complex microbial communities, which is achieved by providing growth substrates enriched in heavy isotopes, usually in the form of 13 C, 18 O, or 15 N. After growth on the substrate and subsequent extraction of microbial biomarkers, typically nucleic acids or proteins, the SIP technique is used for the recovery and analysis of isotope-labeled biomarkers from active microbial populations. In the years following the initial development of DNA- and RNA-based SIP, it was common practice to characterize labeled populations by targeted gene analysis. Such approaches usually involved fingerprint-based analyses or sequencing of clone libraries containing 16S rRNA genes or functional marker gene amplicons. Although molecular fingerprinting remains a valuable approach for rapid confirmation of isotope labeling, recent advances in sequencing technology mean that it is possible to obtain affordable and comprehensive amplicon profiles, metagenomes, or metatranscriptomes from SIP experiments. Not only can the abundance of microbial groups be inferred from metagenomes, but researchers can bin, assemble, and explore individual genomes to build hypotheses about the metabolic capabilities of labeled microorganisms. Analysis of labeled mRNA is a more recent advance that can provide independent metatranscriptome-based analysis of active microorganisms. The power of metatranscriptomics is that mRNA abundance often correlates closely with the corresponding activity of encoded enzymes, thus providing insight into microbial metabolism at the time of sampling. Together, these advances have improved the sensitivity of SIP methods and allow the use of labeled substrates at ecologically relevant concentrations. Particularly as methods improve and costs continue to drop, we expect that the integration of SIP with multiple omics-based methods will become prevalent components of microbial ecology studies

Isotope analysis of water trapped in fluid inclusions in deep sea corals

Science.gov (United States)

Vonhof, Hubert; Reijmer, John; Feenstra, Eline; Mienis, Furu

2015-04-01

Extant Lophelia pertusa deep sea coral specimens from the Loachev mound region in the North Atlantic Ocean contain water filled fluid inclusions in their skeleton. This fluid inclusion water was extracted with a crushing device, and its hydrogen and oxygen isotope ratios analysed. The resulting data span a wide range of isotope values which are remarkably different from the seawater isotope composition of the sites studied. Comparison with food source isotope signatures suggests that coral inclusion water contains a high, but variable proportion of metabolic water. The isotope composition of the inclusion water appears to vary with the position on the deep see coral reef, and shows a correlation with the stable isotope composition of the coral aragonite. This correlation seems to suggest that growth rate and other ecological factors play an important role in determining the isotope composition of fluids trapped in the coral skeleton, which can potentially be developed as a proxy for non-equilibrium isotope fractionation observed in the aragonite skeleton of many of the common deep sea coral species.

Trade-offs in thermal adaptation: the need for a molecular to ecological integration.

Science.gov (United States)

Pörtner, Hans O; Bennett, Albert F; Bozinovic, Francisco; Clarke, Andrew; Lardies, Marco A; Lucassen, Magnus; Pelster, Bernd; Schiemer, Fritz; Stillman, Jonathon H

2006-01-01

Through functional analyses, integrative physiology is able to link molecular biology with ecology as well as evolutionary biology and is thereby expected to provide access to the evolution of molecular, cellular, and organismic functions; the genetic basis of adaptability; and the shaping of ecological patterns. This paper compiles several exemplary studies of thermal physiology and ecology, carried out at various levels of biological organization from single genes (proteins) to ecosystems. In each of those examples, trade-offs and constraints in thermal adaptation are addressed; these trade-offs and constraints may limit species' distribution and define their level of fitness. For a more comprehensive understanding, the paper sets out to elaborate the functional and conceptual connections among these independent studies and the various organizational levels addressed. This effort illustrates the need for an overarching concept of thermal adaptation that encompasses molecular, organellar, cellular, and whole-organism information as well as the mechanistic links between fitness, ecological success, and organismal physiology. For this data, the hypothesis of oxygen- and capacity-limited thermal tolerance in animals provides such a conceptual framework and allows interpreting the mechanisms of thermal limitation of animals as relevant at the ecological level. While, ideally, evolutionary studies over multiple generations, illustrated by an example study in bacteria, are necessary to test the validity of such complex concepts and underlying hypotheses, animal physiology frequently is constrained to functional studies within one generation. Comparisons of populations in a latitudinal cline, closely related species from different climates, and ontogenetic stages from riverine clines illustrate how evolutionary information can still be gained. An understanding of temperature-dependent shifts in energy turnover, associated with adjustments in aerobic scope and performance

Diet-tissue stable isotope (Δ(13)C and Δ(15)N) discrimination factors for multiple tissues from terrestrial reptiles.

Science.gov (United States)

Steinitz, Ronnie; Lemm, Jeffrey M; Pasachnik, Stesha A; Kurle, Carolyn M

2016-01-15

Stable isotope analysis is a powerful tool for reconstructing trophic interactions to better understand drivers of community ecology. Taxon-specific stable isotope discrimination factors contribute to the best use of this tool. We determined the first Δ(13)C and Δ(15)N values for Rock Iguanas (Cyclura spp.) to better understand isotopic fractionation and estimate wild reptile foraging ecology. The Δ(13)C and Δ(15)N values between diet and skin, blood, and scat were determined from juvenile and adult iguanas held for 1 year on a known diet. We measured relationships between iguana discrimination factors and size/age and quantified effects of lipid extraction and acid treatment on stable isotope values from iguana tissues. Isotopic and elemental compositions were determined by Dumas combustion using an elemental analyzer coupled to an isotope ratio mass spectrometer using standards of known composition. The Δ(13)C and Δ(15)N values ranged from -2.5 to +6.5‰ and +2.2 to +7.5‰, respectively, with some differences among tissues and between juveniles and adults. The Δ(13)C values from blood and skin differed among species, but not the Δ(15)N values. The Δ(13)C values from blood and skin and Δ(15)N values from blood were positively correlated with size/age. The Δ(13)C values from scat were negatively correlated with size (not age). Treatment with HCl (scat) and lipid extraction (skin) did not affect the isotope values. These results should aid in the understanding of processes driving stable carbon and nitrogen isotope discrimination factors in reptiles. We provide estimates of Δ(13)C and Δ(15)N values and linear relationships between iguana size/age and discrimination factors for the best interpretation of wild reptile foraging ecology. Copyright © 2015 John Wiley & Sons, Ltd.

Lead isotope in mineral exploration

International Nuclear Information System (INIS)

Gulson, B.L.

1986-01-01

This book provides an up-to-date state-of-the-art review of lead isotopes in mineral exploration. Beginning with an historical review on suggested uses of lead isotopes in mineral exploration, the author then outlines the theoretical aspects of lead isotopes and illustrates that the method is based on well-known principles of radioactive decay, from which isotopic signatures for different styles of mineralization are derived. The varying isotopic signatures are then introduced. The major part of the book details over 40 case histories for base and precious metals, uranium and tin using sampling media such as sulfides, gossans, soils, weathered bedrock, vegetation and groundwaters. Advantages and disadvantages of each are discussed. Examples are given of the use of lead isotopes in testing conceptual models for exploration. The success rate and cost-effectiveness of the method are illustrated by actual exploration examples. Analytical advances which should lower the cost of the method and future uses are outlined. Many of the case histories use recently published or unpublished data, 27 tables of which are given in an appendix. Details of sampling, the methods for obtaining the isotope ratios, and a commercially-available integrated lead isotope service are also provided. (Auth.)

Isotopic niche partitioning between two apex predators over time.

Science.gov (United States)

Drago, Massimiliano; Cardona, Luis; Franco-Trecu, Valentina; Crespo, Enrique A; Vales, Damián G; Borella, Florencia; Zenteno, Lisette; Gonzáles, Enrique M; Inchausti, Pablo

2017-07-01

Stable isotope analyses have become an important tool in reconstructing diets, analysing resource use patterns, elucidating trophic relations among predators and understanding the structure of food webs. Here, we use stable carbon and nitrogen isotope ratios in bone collagen to reconstruct and compare the isotopic niches of adult South American fur seals (Arctocephalus australis; n = 86) and sea lions (Otaria flavescens; n = 49) - two otariid species with marked morphological differences - in the Río de la Plata estuary (Argentina - Uruguay) and the adjacent Atlantic Ocean during the second half of the 20th century and the beginning of the 21st century. Samples from the middle Holocene (n = 7 fur seals and n = 5 sea lions) are also included in order to provide a reference point for characterizing resource partitioning before major anthropogenic modifications of the environment. We found that the South American fur seals and South American sea lions had distinct isotopic niches during the middle Holocene. Isotopic niche segregation was similar at the beginning of the second half of the 20th century, but has diminished over time. The progressive convergence of the isotopic niches of these two otariids during the second half of the 20th century and the beginning of the 21st century is most likely due to the increased reliance of South American fur seals on demersal prey. This recent dietary change in South American fur seals can be explained by at least two non-mutually exclusive mechanisms: (i) the decrease in the abundance of sympatric South American sea lions as a consequence of small colony size and high pup mortality resulting from commercial sealing; and (ii) the decrease in the average size of demersal fishes due to intense fishing of the larger class sizes, which may have increased their accessibility to those eared seals with a smaller mouth gape, that is, South American fur seals of both sexes and female South American sea lions. © 2017 The Authors

FFI: A software tool for ecological monitoring

Science.gov (United States)

Duncan C. Lutes; Nathan C. Benson; MaryBeth Keifer; John F. Caratti; S. Austin Streetman

2009-01-01

A new monitoring tool called FFI (FEAT/FIREMON Integrated) has been developed to assist managers with collection, storage and analysis of ecological information. The tool was developed through the complementary integration of two fire effects monitoring systems commonly used in the United States: FIREMON and the Fire Ecology Assessment Tool. FFI provides software...

Integrated presentation of ecological risk from multiple stressors

OpenAIRE

Goussen, Benoit Regis Marc; Price, Oliver R.; Rendal, Cecilie; Ashauer, Roman

2016-01-01

Current environmental risk assessments (ERA) do not account explicitly for ecological factors (e.g. species composition, temperature or food availability) and multiple stressors. Assessing mixtures of chemical and ecological stressors is needed as well as accounting for variability in environmental conditions and uncertainty of data and models. Here we propose a novel probabilistic ERA framework to overcome these limitations, which focusses on visualising assessment outcomes by construct-ing ...

Detection of the Nitrate Pollution Sources in Shallow Aquifer, Using Integration of RS&GIS with Stable Isotopes Technologies

Science.gov (United States)

Shakak, N. B. I.

2018-04-01

Geographical information system (GIS) and remote sensing technique is a tool which is used for acquiring data from space, storing, analyzing and displaying spatial data, also can use for investigating source of environmental pollution which is affect health. Sudan landsat mosaic image which acquired in 2013 was used in this study to develop land use and land cover maps for tow selected study area, Khartoum urban area, and Bara locality in North kordofan state western Sudan. The main objective to assess the source of Nitrate pollution in shallow aquifer. ERDAS software was used to create land cover-land use maps for the study areas. For Khartoum town we used land sat mosaic image which acquire in 2013, and used supervised classification which more closely controlled than unsupervised. In this process, we select pixel that represent patterns you recognized or can identify with help from knowledge of the data, the classes desired, and the algorithm to be used is required. In this paper we integrated the (GIS&RS), and stable isotopes methods for fingerprinting Nitrate sources in shallow boreholes. The global positioning system (GPS), used in the field to identify the shallow boreholes location in a three dimensional coordinate (Latitude, longitude, and altitude), Water samples were collected from 19 shallow boreholes in the study areas according to the standard sampling method send to laboratory to measure stable nitrogen (δ15Nnitrate), and Nitrate-oxygen (δ18Onitrate) isotopes. Analysis were conducted by using isotope ratio mass spectrometry (IRMS). We can conclude that, special distribution and integration of GIs & RS help to identify the source of nitrate pollution.

DETECTION OF THE NITRATE POLLUTION SOURCES IN SHALLOW AQUIFER, USING INTEGRATION OF RS&GIS WITH STABLE ISOTOPES TECHNOLOGIES

Directory of Open Access Journals (Sweden)

N. B. I. Shakak

2018-04-01

Full Text Available Geographical information system (GIS and remote sensing technique is a tool which is used for acquiring data from space, storing, analyzing and displaying spatial data, also can use for investigating source of environmental pollution which is affect health. Sudan landsat mosaic image which acquired in 2013 was used in this study to develop land use and land cover maps for tow selected study area, Khartoum urban area, and Bara locality in North kordofan state western Sudan. The main objective to assess the source of Nitrate pollution in shallow aquifer. ERDAS software was used to create land cover-land use maps for the study areas. For Khartoum town we used land sat mosaic image which acquire in 2013, and used supervised classification which more closely controlled than unsupervised. In this process, we select pixel that represent patterns you recognized or can identify with help from knowledge of the data, the classes desired, and the algorithm to be used is required. In this paper we integrated the (GIS&RS, and stable isotopes methods for fingerprinting Nitrate sources in shallow boreholes. The global positioning system (GPS, used in the field to identify the shallow boreholes location in a three dimensional coordinate (Latitude, longitude, and altitude, Water samples were collected from 19 shallow boreholes in the study areas according to the standard sampling method send to laboratory to measure stable nitrogen (δ15Nnitrate, and Nitrate-oxygen (δ18Onitrate isotopes. Analysis were conducted by using isotope ratio mass spectrometry (IRMS. We can conclude that, special distribution and integration of GIs & RS help to identify the source of nitrate pollution.

No influence of CO2 on stable isotope analyses of soil waters with off-axis integrated cavity output spectroscopy (OA-ICOS).

Science.gov (United States)

Sprenger, Matthias; Tetzlaff, Doerthe; Soulsby, Chris

2017-03-15

It was recently shown that the presence of CO 2 affects the stable isotope (δ 2 H and δ 18 O values) analysis of water vapor via Wavelength-Scanned Cavity Ring-Down Spectroscopy. Here, we test how much CO 2 is emitted from soil samples and if the CO 2 in the headspace influences the isotope analysis with the direct equilibration method by Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS). The headspace above different amounts of sparkling water was sampled, and its stable isotopic composition (δ 2 H and δ 18 O values) and CO 2 concentration were measured by direct equilibration and by gas chromatography, respectively. In addition, the headspace above soil samples was analyzed in the same way. Furthermore, the gravimetric water content and the loss on ignition were measured for the soil samples. The experiment with the sparkling water showed that CO 2 does not influence the stable isotope analysis by OA-ICOS. CO 2 was emitted from the soil samples and correlated with the isotopic fractionation signal, but no causal relationship between the two was determined. Instead, the fractionation signal in pore water isotopes can be explained by soil evaporation and the CO 2 can be related to soil moisture and organic matter which both enhance microbial activity. We found, despite the high CO 2 emissions from soil samples, no need for a post-correction of the pore water stable isotope analysis results, since there is no relation between CO 2 concentrations and the stable isotope results of vapor samples obtained with OA-ICOS. © 2016 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd. © 2016 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd.

European ecological networks and greenways

DEFF Research Database (Denmark)

Kristiansen, Ib; Jongman, Rob H.G.; Kulvik, Mart

2004-01-01

renewed. Within the framework of nature conservation, the notion of an ecological network has become increasingly important. Throughout Europe, regional and national approaches are in different phases of development, which are all based on recent landscape ecological principles. Ecological networks......In the context of European integration, networks are becoming increasingly important in both social and ecological sense. Since the beginning of the 1990s, societal and scientific exchanges are being restructured as the conceptual approaches towards new nature conservation strategies have been....... This complex interaction between cultural and natural features results in quite different ways for the elaboration of ecological networks and greenways....

Stable isotopes suggest differences in diet between historic and reintroduced Przewalskís horses in the Gobi desert

Science.gov (United States)

Burnik Šturm, Martina; Spasskaya, Natalia N.; Sablin, Mikhail V.; Voigt, Christian C.; Kaczensky, Petra

2016-04-01

In historic times, two wild equid species, the Przewalski᾽s horse (PH; Equus ferus przewalskii) and the Asiatic wild ass (khulan, KH; Equus hemionus), roamed the Eurasian steppes. By the end of the 1960s, PHs had been driven to extinction in the wild and the range of KHs became severely restricted to the least productive habitats. However, PHs survived in captivity and reintroductions since the 1990s have brought the species back to parts of its native range in Mongolia and northern China where they again overlap with KHs. Ecological research on PHs and KHs has increased in recent years, but very little information is available on the ecology of the original PHs prior to extinction in the wild. We applied stable isotope analysis (13C, 15N, and 2H) of segmentally cut tail hair of PHs and KHs, collected during expeditions in NW China and SW Mongolia in 1889-1899, to draw inferences about the species feeding ecology. We compared tail hair isotope patterns of historic individuals to those of their extant counterparts from the Mongolian Gobi. A previous study of isotopic tail hair signatures of extant PHs (N=6) and KHs (N=6) suggested species specific differences in diet, with PHs being year-round grazers, but KHs switching between being grazers in summer and mixed feeders in winter (Burnik Šturm et al., in prep.). The comparison of isotope patterns of extant with historic samples confirms diet seasonality in historic KHs (N=3), but detects the same seasonality in five out of six PHs, suggesting that historic PHs had a different isotopic dietary niche than extant PHs. While we are still unable to fully understand the underlying reasons for this change in PHs, our results clearly suggest that the isotopic dietary niche of PHs was wider in the past, suggesting a higher diet flexibility, and overlapped with that of KHs, suggesting a high competition potential over Gobi pastures between the two equid species in historic times. Reference: Burnik Šturm, M., Ganbaatar, O

Isotope variations of hydrogen, carbon and nitrogen in florae from the Schirmacher Oasis, East Antarctica

International Nuclear Information System (INIS)

Strauch, G.; Haendel, D.; Maass, I.; Muehle, K.; Runge, A.

1982-01-01

Comparative biochemical and isotope-chemical investigations of cosmopolitical plants open up ways of obtaining parameters from different parts of the earth which are characterized by variations in the habitat due to different environments. As an Antarctic oasis the Schirmacher Oasis disposes of adequate favourable ecological conditions for the growth of lower plants. In the present paper results of isotope studies of lichens, mosses and algae of the Schirmacher Oasis are given and peculiarities of the habitats which influence the isotope contents of the plants are discussed. (author)

Isotopic Discrimination During Leaf Litter Decomposition

Science.gov (United States)

Ngao, J.; Rubino, M.

2006-12-01

Methods involving stable isotopes have been successfully applied since decades in various research fields. Tracing 13C natural abundance in ecosystem compartments greatly enhanced the understanding of the C fluxes in the plant-soil-atmosphere C exchanges when compartments present different C isotopic signatures (i.e. atmospheric CO2 vs photosynthetic leaves, C3 vs C4; etc.). However, the assumption that no isotopic discrimination occurs during respiration is commonly made in numbers of C isotope-based ecological studies. Furthermore, verifications of such assumption are sparse and not enough reliable. The aim of our study is to assess the potential isotopic discrimination that may occur during litter decomposition. Leaf litter from an Arbutus unedo (L.) stand (Tolfa, Italy) was incubated in 1L jars, under constant laboratory conditions (i.e. 25 ° C and 135% WC). During the entire incubation period, gravimetric mass loss, litter respiration rates and the isotopic composition of respired CO2 are monitored at regular intervals. Data from 7 months of incubation will be presented and discussed. After two months, the litter mass loss averaged 16% of initial dry mass. During the same time-period, the respiration rate decreased significantly by 58% of the initial respiration rate. Isotopic compositions of respired CO2 ranged between -27.95‰ and - 25.69‰. Mean values did not differ significantly among the sampling days, in spite of an apparent enrichment in 13C of respired CO2 with time. The significance of these isotopic enrichment will be determined at a longer time scale. They may reveal both/either a direct microbial discrimination during respiration processes and/or a use of different litter compounds as C source along time. Further chemical and compound-specific isotopic analysis of dry matter will be performed in order to clarify these hypotheses. This work is part of the "ALICE" project, funded by the European Union's Marie Curie Fellowship Actions that aims to

Evidence and opportunities for integrating landscape ecology into natural resource planning across multiple-use landscapes

Science.gov (United States)

Trammel, E. Jamie; Carter, Sarah; Haby, Travis S.; Taylor, Jason J.

2018-01-01

Enhancing natural resource management has been a focus of landscape ecology since its inception, but numerous authors argue that landscape ecology has not yet been effective in achieving the underlying goal of planning and designing sustainable landscapes. We developed nine questions reflecting the application of fundamental research topics in landscape ecology to the landscape planning process and reviewed two recent landscape-scale plans in western North America for evidence of these concepts in plan decisions. Both plans considered multiple resources, uses, and values, including energy development, recreation, conservation, and protection of cultural and historic resources. We found that land use change and multiscale perspectives of resource uses and values were very often apparent in planning decisions. Pattern-process relationships, connectivity and fragmentation, ecosystem services, landscape history, and climate change were reflected less frequently. Landscape sustainability was considered only once in the 295 decisions reviewed, and outputs of landscape models were not referenced. We suggest six actionable opportunities for further integrating landscape ecology concepts into landscape planning efforts: 1) use landscape sustainability as an overarching goal, 2) adopt a broad ecosystem services framework, 3) explore the role of landscape history more comprehensively, 4) regularly consider and accommodate potential effects of climate change, 5) use landscape models to support plan decisions, and 6) promote a greater presence of landscape ecologists within agencies that manage large land bases and encourage active involvement in agency planning efforts. Together these actions may improve the defensibility, durability, and sustainability of landscape plan decisions.

Assessing Cross-disciplinary Efficiency of Soil Amendments for Agro-biologically, Economically, and Ecologically Integrated Soil Health Management

Science.gov (United States)

2010-01-01

Preventive and/or manipulative practices will be needed to maintain soil's biological, physiochemical, nutritional, and structural health in natural, managed, and disturbed ecosystems as a foundation for food security and global ecosystem sustainability. While there is a substantial body of interdisciplinary science on understanding function and structure of soil ecosystems, key gaps must be bridged in assessing integrated agro-biological, ecological, economical, and environmental efficiency of soil manipulation practices in time and space across ecosystems. This presentation discusses the application of a fertilizer use efficiency (FUE) model for assessing agronomic, economic, ecological, environmental, and nematode (pest) management efficiency of soil amendments. FUE is defined as increase in host productivity and/or decrease in plant-parasitic nematode population density in response to a given fertilizer treatment. Using the effects of nutrient amendment on Heterodera glycines population density and normalized difference vegetative index (indicator of physiological activities) of a soybean cultivar ‘CX 252’, how the FUE model recognizes variable responses and separates nutrient deficiency and toxicity from nematode parasitism as well as suitability of treatments designed to achieve desired biological and physiochemical soil health conditions is demonstrated. As part of bridging gaps between agricultural and ecological approaches to integrated understanding and management of soil health, modifications of the FUE model for analyzing the relationships amongst nematode community structure, soil parameters (eg. pH, nutrients, %OM), and plant response to soil amendment is discussed. PMID:22736840

Microbial ecology to manage processes in environmental biotechnology.

Science.gov (United States)

Rittmann, Bruce E

2006-06-01

Microbial ecology and environmental biotechnology are inherently tied to each other. The concepts and tools of microbial ecology are the basis for managing processes in environmental biotechnology; and these processes provide interesting ecosystems to advance the concepts and tools of microbial ecology. Revolutionary advancements in molecular tools to understand the structure and function of microbial communities are bolstering the power of microbial ecology. A push from advances in modern materials along with a pull from a societal need to become more sustainable is enabling environmental biotechnology to create novel processes. How do these two fields work together? Five principles illuminate the way: (i) aim for big benefits; (ii) develop and apply more powerful tools to understand microbial communities; (iii) follow the electrons; (iv) retain slow-growing biomass; and (v) integrate, integrate, integrate.

Aspects of an ecological theory of language

DEFF Research Database (Denmark)

Bang, J. C.; Trampe, W.

2014-01-01

Our aim and knowledge-constitutive interest is to identify some central aspects of an ecological theory of language. In our understanding of building an integrative ecological theory of language, it seems useful to look first for roots of a special ecological understanding of language. Here...

Isotopic characterization of flight feathers in two pelagic seabirds: Sampling strategies for ecological studies

Science.gov (United States)

Wiley, Anne E.; Ostrom, Peggy H.; Stricker, Craig A.; James, Helen F.; Gandhi, Hasand

2010-01-01

We wish to use stable-isotope analysis of flight feathers to understand the feeding behavior of pelagic seabirds, such as the Hawaiian Petrel (Pterodroma sandwichensis) and Newell’s Shearwater (Puffinus auricularis newelli). Analysis of remiges is particularly informative because the sequence and timing of remex molt are often known. The initial step, reported here, is to obtain accurate isotope values from whole remiges by means of a minimally invasive protocol appropriate for live birds or museum specimens. The high variability observed in D13C and D15N values within a feather precludes the use of a small section of vane. We found the average range within 42 Hawaiian Petrel remiges to be 1.3‰ for both D13C and D15N and that within 10 Newell’s Shearwater remiges to be 1.3‰ and 0.7‰ for D13C and D15N, respectively. The D13C of all 52 feathers increased from tip to base, and the majority of Hawaiian Petrel feathers showed an analogous trend in D15N. Although the average range of DD in 21 Hawaiian Petrel remiges was 11‰, we found no longitudinal trend. We discuss influences of trophic level, foraging location, metabolism, and pigmentation on isotope values and compare three methods of obtaining isotope averages of whole feathers. Our novel barb-sampling protocol requires only 1.0 mg of feather and minimal preparation time. Because it leaves the feather nearly intact, this protocol will likely facilitate obtaining isotope values from remiges of live birds and museum specimens. As a consequence, it will help expand the understanding of historical trends in foraging behavior

Ecological analyses and applications

International Nuclear Information System (INIS)

Kroodsma, R.L.; Craig, R.B.; Hildebrand, S.G.

1978-01-01

Progress is reported on the following: assessment of nuclear power plants; ecological analysis of uranium mining, milling, and fuel fabrication; environmental impact statements concerning uranium enrichment facilities; site evaluations for storage of radioactive wastes; ecological analysis of geothermal energy development; enhanced oil recovery; environmental monitoring plan for modular integrated utility systems; and fossil energy environmental project

[Trophic niche partitioning of pelagic sharks in Central Eastern Pacific inferred from stable isotope analysis.

Science.gov (United States)

Li, Yun Kai; Gao, Xiao di; Wang, Lin Yu; Fang, Lin

2018-01-01

As the apex predators of the open ocean ecosystems, pelagic sharks play important roles in stabilizing the marine food web through top-down control. Stable isotope analysis is a powerful tool to investigate the feeding ecology. The carbon and nitrogen isotope ratios can be used to trace food source and evaluate the trophic position of marine organisms. In this study, the isotope values of 130 pelagic sharks from 8 species in Central Eastern Pacific were analyzed and their trophic position and niche were calculated to compare the intra/inter-specific resource partitioning in the Central Eastern Pacific ecosystem. The results exhibited significant differences in both carbon and nitrogen isotope values among the shark species. The trophic levels ranged from 4.3 to 5.4 in the Central Eastern Pacific shark community. The trophic niche of blue sharks and shortfin mako sharks showed no overlap with the other shark species, exhibiting unique ecological roles in the open ocean food web. These data highlighted the diverse roles among pelagic sharks, supporting previous findings that this species is not trophically redundant and the trophic niche of pelagic sharks can not be simply replaced by those of other top predator species.

Integrating network ecology with applied conservation: a synthesis and guide to implementation.

Science.gov (United States)

Kaiser-Bunbury, Christopher N; Blüthgen, Nico

2015-07-10

Ecological networks are a useful tool to study the complexity of biotic interactions at a community level. Advances in the understanding of network patterns encourage the application of a network approach in other disciplines than theoretical ecology, such as biodiversity conservation. So far, however, practical applications have been meagre. Here we present a framework for network analysis to be harnessed to advance conservation management by using plant-pollinator networks and islands as model systems. Conservation practitioners require indicators to monitor and assess management effectiveness and validate overall conservation goals. By distinguishing between two network attributes, the 'diversity' and 'distribution' of interactions, on three hierarchical levels (species, guild/group and network) we identify seven quantitative metrics to describe changes in network patterns that have implications for conservation. Diversity metrics are partner diversity, vulnerability/generality, interaction diversity and interaction evenness, and distribution metrics are the specialization indices d' and [Formula: see text] and modularity. Distribution metrics account for sampling bias and may therefore be suitable indicators to detect human-induced changes to plant-pollinator communities, thus indirectly assessing the structural and functional robustness and integrity of ecosystems. We propose an implementation pathway that outlines the stages that are required to successfully embed a network approach in biodiversity conservation. Most importantly, only if conservation action and study design are aligned by practitioners and ecologists through joint experiments, are the findings of a conservation network approach equally beneficial for advancing adaptive management and ecological network theory. We list potential obstacles to the framework, highlight the shortfall in empirical, mostly experimental, network data and discuss possible solutions. Published by Oxford University

Using Ecological Indicators and a Decision Support System for Integrated Ecological Assessment at Two National Park Units in the Mid-Atlantic Region, USA

Science.gov (United States)

Mahan, Carolyn G.; Young, John A.; Miller, Bruce J.; Saunders, Michael C.

2015-02-01

We implemented an integrated ecological assessment using a GIS-based decision support system model for Upper Delaware Scenic and Recreational River (UPDE) and Delaware Water Gap National Recreation Area (DEWA)—national park units with the mid-Atlantic region of the United States. Our assessment examined a variety of aquatic and terrestrial indicators of ecosystem components that reflect the parks' conservation purpose and reference condition. Our assessment compared these indicators to ecological thresholds to determine the condition of park watersheds. Selected indicators included chemical and physical measures of water quality, biologic indicators of water quality, and landscape condition measures. For the chemical and physical measures of water quality, we used a water quality index and each of its nine components to assess the condition of water quality in each watershed. For biologic measures of water quality, we used the Ephemeroptera, Plecoptera, Trichoptera aquatic macroinvertebrate index and, secondarily, the Hilsenhoff aquatic macroinvertebrate index. Finally, for the landscape condition measures of our model, we used percent forest and percent impervious surface. Based on our overall assessment, UPDE and DEWA watersheds had an ecological assessment score of 0.433 on a -1 to 1 fuzzy logic scale. This score indicates that, in general, the natural resource condition within watersheds at these parks is healthy or ecologically unimpaired; however, we had only partial data for many of our indicators. Our model is iterative and new data may be incorporated as they become available. These natural parks are located within a rapidly urbanizing landscape—we recommend that natural resource managers remain vigilant to surrounding land uses that may adversely affect natural resources within the parks.

Isotope exchange study of the dissociation of metal - humic substance complexes

Czech Academy of Sciences Publication Activity Database

Mizera, J.; Jansová, A.; Hvoždová, I.; Beneš, P.; Novák, František

2003-01-01

Roč. 53, A (2003), s. A97-A101 ISSN 0011-4626 Institutional research plan: CEZ:AV0Z6066911; CEZ:MSM 210000019 Keywords : isotope exchange * dissociation of metal * humic substance complexes Subject RIV: EH - Ecology, Behaviour Impact factor: 0.263, year: 2003

Global patterns of foliar nitrogen isotopes and their relationships with climate, mycorrhizal fungi, foliar nutrient concentrations, and nitrogen availability

DEFF Research Database (Denmark)

Craine, J M; Elmore, A J; Aidar, M P M

2009-01-01

Ratios of nitrogen (N) isotopes in leaves could elucidate underlying patterns of N cycling across ecological gradients. To better understand global-scale patterns of N cycling, we compiled data on foliar N isotope ratios (d15N), foliar N concentrations, mycorrhizal type and climate for over 11 00...

The conservation genetics juggling act: Integrating genetics and ecology, science and policy

Science.gov (United States)

Haig, Susan M.; Miller, Mark P.; Bellinger, Renee; Draheim, Hope M.; Mercer, Dacey; Mullins, Tom

2016-01-01

The field of conservation genetics, when properly implemented, is a constant juggling act integrating molecular genetics, ecology, and demography with applied aspects concerning managing declining species or implementing conservation laws and policies. This young field has grown substantially since the 1980’s following development of the polymerase chain reaction and now into the genomics era. Our lab has “grown up” with the field, having worked on these issues for over three decades. Our multi-disciplinary approach entails understanding the behavior and ecology of species as well as the underlying processes that contribute to genetic viability. Taking this holistic approach provides a comprehensive understanding of factors that influence species persistence and evolutionary potential while considering annual challenges that occur throughout their life cycle. As a federal lab, we are often addressing the needs of the U.S. Fish and Wildlife Service in their efforts to list, de-list or recover species. Nevertheless, there remains an overall communication gap between research geneticists and biologists who are charged with implementing their results. Therefore, we outline the need for a National Center for Small Population Biology to ameliorate this problem and provide organizations charged with making status decisions firmer ground from which to make their critical decisions. 

Reconstruction of the biogeochemistry and ecology of photoautotrophs based on the nitrogen and carbon isotopic compositions of vanadyl porphyrins from Miocene siliceous sediments

Directory of Open Access Journals (Sweden)

Y. Kashiyama

2008-05-01

Full Text Available We determined both the nitrogen and carbon isotopic compositions of various vanadyl alkylporphyrins isolated from siliceous marine sediments of the Onnagawa Formation (middle Miocene, northeastern Japan to investigate the biogeochemistry and ecology of photoautotrophs living in the paleo-ocean. The distinctive isotopic signals support the interpretations of previous works that the origin of 17-nor-deoxophylloerythroetioporphyrin (DPEP is chlorophylls-c_1-3, whereas 8-nor-DPEP may have originated from chlorophylls-a₂ or b₂ or bacteriochlorophyll-a. Although DPEP and cycloheptanoDPEP are presumably derived from common precursory pigments, their isotopic compositions differed in the present study, suggesting that the latter represents a specific population within the photoautotrophic community. The average δ¹⁵N value for the entire photoautotrophic community is estimated to be –2 to +1‰ from the δ¹⁵N values of DPEP (–6.9 to –3.6‰; n=7, considering that the empirical isotopic relationships that the tetrapyrrole nuclei of chloropigments are depleted in ¹⁵N by ~4.8‰ and enriched in ¹³C by ~1.8‰ relative to the whole cells. This finding suggests that nitrogen utilized in the primary production was supplied mainly through N₂-fixation by diazotrophic cyanobacteria. Based on the δ¹³C values of DPEP (–17.9 to –15.6‰; n=7, we estimated isotopic fractionation associated with photosynthetic carbon fixation to be 8–14‰. This range suggests the importance of β-carboxylation and/or active transport of the carbon substrate, indicating in turn the substantial contribution of diazotrophic cyanobacteria to primary production. Based on the δ¹⁵N values of 17-nor-DPEP (–7.4 to –2.4‰ n=7, the δ¹⁵N range of chlorophylls-c-producing algae was estimated to be –3

Integrating ecological knowledge, public perception and urgency of action into invasive species management.

Science.gov (United States)

Caplat, Paul; Coutts, Shaun R

2011-11-01

Recently Prévot-Julliard and colleagues presented a concept paper on biological conservation strategies using exotic species as a case study. They emphasized the difficulty of integrating conservation into a broad picture that accounts for public perception as well as scientific knowledge. We support this general call for better integration of society in conservation research, but we believe that the original framework might misguide conservation practices if wrongly interpreted. Our objective is to complement their paper and correct a few misleading points, by showing that (1) for regions of high endemicity "reservation" may be the best conservation practice, and does not prevent public participation, (2) aiming for broad societal agreement is valuable, but in some cases risky, and always complex, and (3) calling a harmful invasive species harmful shouldn't be an issue. The Australian context provides us with many cases of the labeling of exotic species as harmful or not, using inputs from scientists, industry, and the public. Integration of social and scientific points of view can only improve conservation on the ground if it allows managers to use the ecological, economic and social impacts of exotic species to prioritize conservation actions in an operative way.

Diet and stable isotope analyses reveal the feeding ecology of the orangeback squid Sthenoteuthis pteropus (Steenstrup 1855 (Mollusca, Ommastrephidae in the eastern tropical Atlantic.

Directory of Open Access Journals (Sweden)

Véronique Merten

Full Text Available In the eastern tropical Atlantic, the orangeback flying squid Sthenoteuthis pteropus (Steenstrup 1855 (Cephalopoda, Ommastrephidae is a dominant species of the epipelagic nekton community. This carnivore squid has a short lifespan and is one of the fastest-growing squids. In this study, we characterise the role of S. pteropus in the pelagic food web of the eastern tropical Atlantic by investigating its diet and the dynamics of its feeding habits throughout its ontogeny and migration. During three expeditions in the eastern tropical Atlantic in 2015, 129 specimens were caught by hand jigging. Stomach content analyses (via visual identification and DNA barcoding were combined with stable isotope data (∂15N and ∂13C of muscle tissue to describe diet, feeding habits and trophic ecology of S. pteropus. Additionally, stable isotope analyses of incremental samples along the squid's gladius-the chitinous spiniform structure supporting the muscles and organs-were carried out to explore possible diet shifts through ontogeny and migration. Our results show that S. pteropus preys mainly on myctophid fishes (e.g. Myctophum asperum, Myctophum nitidulum, Vinciguerria spp., but also on other teleost species, cephalopods (e.g. Enoploteuthidae, Bolitinidae, Ommastrephidae, crustaceans and possibly on gelatinous zooplankton as well. The squid shows a highly opportunistic feeding behaviour that includes cannibalism. Our study indicates that the trophic position of S. pteropus may increase by approximately one trophic level from a mantle length of 15 cm to 47 cm. The reconstructed isotope-based feeding chronologies of the gladii revealed high intra- and inter-individual variability in the squid's trophic position and foraging area. These findings are not revealed by diet or muscle tissue stable isotope analysis. This suggests a variable and complex life history involving individual variation and migration. The role of S. pteropus in transferring energy and

Diet and stable isotope analyses reveal the feeding ecology of the orangeback squid Sthenoteuthis pteropus (Steenstrup 1855) (Mollusca, Ommastrephidae) in the eastern tropical Atlantic.

Science.gov (United States)

Merten, Véronique; Christiansen, Bernd; Javidpour, Jamileh; Piatkowski, Uwe; Puebla, Oscar; Gasca, Rebeca; Hoving, Henk-Jan T

2017-01-01

In the eastern tropical Atlantic, the orangeback flying squid Sthenoteuthis pteropus (Steenstrup 1855) (Cephalopoda, Ommastrephidae) is a dominant species of the epipelagic nekton community. This carnivore squid has a short lifespan and is one of the fastest-growing squids. In this study, we characterise the role of S. pteropus in the pelagic food web of the eastern tropical Atlantic by investigating its diet and the dynamics of its feeding habits throughout its ontogeny and migration. During three expeditions in the eastern tropical Atlantic in 2015, 129 specimens were caught by hand jigging. Stomach content analyses (via visual identification and DNA barcoding) were combined with stable isotope data (∂15N and ∂13C) of muscle tissue to describe diet, feeding habits and trophic ecology of S. pteropus. Additionally, stable isotope analyses of incremental samples along the squid's gladius-the chitinous spiniform structure supporting the muscles and organs-were carried out to explore possible diet shifts through ontogeny and migration. Our results show that S. pteropus preys mainly on myctophid fishes (e.g. Myctophum asperum, Myctophum nitidulum, Vinciguerria spp.), but also on other teleost species, cephalopods (e.g. Enoploteuthidae, Bolitinidae, Ommastrephidae), crustaceans and possibly on gelatinous zooplankton as well. The squid shows a highly opportunistic feeding behaviour that includes cannibalism. Our study indicates that the trophic position of S. pteropus may increase by approximately one trophic level from a mantle length of 15 cm to 47 cm. The reconstructed isotope-based feeding chronologies of the gladii revealed high intra- and inter-individual variability in the squid's trophic position and foraging area. These findings are not revealed by diet or muscle tissue stable isotope analysis. This suggests a variable and complex life history involving individual variation and migration. The role of S. pteropus in transferring energy and nutrients from

Ecological analyses and applications

International Nuclear Information System (INIS)

Brocksen, R.W.

1977-01-01

Progress is reported on the following: analysis of ecological impacts of construction and operation of nuclear power plants; fossil energy environmental project; ecological analysis of geothermal energy development; HUD modular integrated utility systems; expansion of uranium enrichment facilities at Portsmouth; environmental standard review plans; environmental assessment of cooling reservoirs; and analysis of fish impingement at power plants in the southeastern United States

Transmutation of Isotopes --- Ecological and Energy Production Aspects

Science.gov (United States)

Gudowski, Waclaw

2000-01-01

This paper describes principles of Accelerator-Driven Transmutation of Nuclear Wastes (ATW) and gives some flavour of the most important topics which are today under investigations in many countries. An assessment of the potential impact of ATW on a future of nuclear energy is also given. Nuclear reactors based on self-sustained fission reactions --- after spectacular development in fifties and sixties, that resulted in deployment of over 400 power reactors --- are wrestling today more with public acceptance than with irresolvable technological problems. In a whole spectrum of reasons which resulted in today's opposition against nuclear power few of them are very relevant for the nuclear physics community and they arose from the fact that development of nuclear power had been handed over to the nuclear engineers and technicians with some generically unresolved problems, which should have been solved properly by nuclear scientists. In a certain degree of simplification one can say, that most of the problems originate from very specific features of a fission phenomenon: self-sustained chain reaction in fissile materials and very strong radioactivity of fission products and very long half-life of some of the fission and activation products. And just this enormous concentration of radioactive fission products in the reactor core is the main problem of managing nuclear reactors: it requires unconditional guarantee for the reactor core integrity in order to avoid radioactive contamination of the environment; it creates problems to handle decay heat in the reactor core and finally it makes handling and/or disposal of spent fuel almost a philosophical issue, due to unimaginable long time scales of radioactive decay of some isotopes. A lot can be done to improve the design of conventional nuclear reactors (like Light Water Reactors); new, better reactors can be designed but it seems today very improbable to expect any radical change in the public perception of conventional

Interim balance: Ecology

International Nuclear Information System (INIS)

Kogon, E.; Jungk, R.

1981-01-01

Subjects: The ecology problem - world wide. Sectoral balances: The examples of energy, transportation, chemistry, agriculture and food industry, water supply. Destruction of nature and human discord. Conservatives in our political parties and their views on environmental protection. Alliance between reds and 'greens', integration between reds and greens. The Rhine initiative. Lead respects no borders, experiences of citizens' action groups in Lothringia and the Saar district. International airport Munich-II/comments by a protestant. 'Give priority to life'/A hearing on environmental protection. 4:96 - 'greens' in the Bremen Senate. Policy in a hard-hearing world/psychology of citizens' action groups. Critical ecological research and scientific establishment. Full productivity and ecology. The deluge to follow/Hints on how to build an ark. Symbiosis is more than coexistence/Ecologists' social theory. Throwing in two hundred elementary particles/on the way to an ecological concept of science. Scientific journals. Alternative literature. Teaching model for a teaching subject 'ecology'. (orig.) [de

Information Ecology

DEFF Research Database (Denmark)

Christiansen, Ellen Tove

2006-01-01

in the 1960ties, and chosen here because it integrates cultural and psychological trajectories in a theory of living settings. The pedagogical-didactical paradigm comprises three distinct information ecologies, named after their intended outcome: the problem-setting, the exploration-setting, and the fit...

Integrated conceptual ecological model and habitat indices for the southwest Florida coastal wetlands

Science.gov (United States)

Wingard, G. Lynn; Lorenz, J. L.

2014-01-01

The coastal wetlands of southwest Florida that extend from Charlotte Harbor south to Cape Sable, contain more than 60,000 ha of mangroves and 22,177 ha of salt marsh. These coastal wetlands form a transition zone between the freshwater and marine environments of the South Florida Coastal Marine Ecosystem (SFCME). The coastal wetlands provide diverse ecosystem services that are valued by society and thus are important to the economy of the state. Species from throughout the region spend part of their life cycle in the coastal wetlands, including many marine and coastal-dependent species, making this zone critical to the ecosystem health of the Everglades and the SFCME. However, the coastal wetlands are increasingly vulnerable due to rising sea level, changes in storm intensity and frequency, land use, and water management practices. They are at the boundary of the region covered by the Comprehensive Everglades Restoration Plan (CERP), and thus are impacted by both CERP and marine resource management decisions. An integrated conceptual ecological model (ICEM) for the southwest coastal wetlands of Florida was developed that illustrates the linkages between drivers, pressures, ecological process, and ecosystem services. Five ecological indicators are presented: (1) mangrove community structure and spatial extent; (2) waterbirds; (3) prey-base fish and macroinvertebrates; (4) crocodilians; and (5) periphyton. Most of these indicators are already used in other areas of south Florida and the SFCME, and therefore will allow metrics from the coastal wetlands to be used in system-wide assessments that incorporate the entire Greater Everglades Ecosystem.

The thermal neutron absorption cross-sections, resonance integrals and resonance parameters of silicon and its stable isotopes

International Nuclear Information System (INIS)

Story, J.S.

1969-09-01

The data available up to the end of November 1968 on the thermal neutron absorption cross-sections, resonance absorption integrals, and resonance parameters of silicon and its stable isotopes are collected and discussed. Estimates are given of the mean spacing of the energy levels of the compound nuclei near the neutron binding energy. It is concluded that the thermal neutron absorption cross-section and resonance absorption integral of natural silicon are not well established. The data on these two parameters are somewhat correlated, and three different assessments of the resonance integral are presented which differ over-all by a factor of 230. Many resonances have been detected by charged particle reactions which have not yet been observed in neutron cross-section measurements. One of these resonances of Si 2 8, at E n = 4 ± 5 keV might account for the large resonance integral which is derived, very uncertainly, from integral data. The principal source of the measured resonance integral of Si 3 0 has not yet been located. The thermal neutron absorption cross-section of Si 2 8 appears to result mainly from a negative energy resonance, possibly the resonance at E n = - 59 ± 5 keV detected by the Si 2 8 (d,p) reaction. (author)

Searching for the true diet of marine predators: incorporating Bayesian priors into stable isotope mixing models.

Directory of Open Access Journals (Sweden)

André Chiaradia

Full Text Available Reconstructing the diet of top marine predators is of great significance in several key areas of applied ecology, requiring accurate estimation of their true diet. However, from conventional stomach content analysis to recent stable isotope and DNA analyses, no one method is bias or error free. Here, we evaluated the accuracy of recent methods to estimate the actual proportion of a controlled diet fed to a top-predator seabird, the Little penguin (Eudyptula minor. We combined published DNA data of penguins scats with blood plasma δ(15N and δ(13C values to reconstruct the diet of individual penguins fed experimentally. Mismatch between controlled (true ingested diet and dietary estimates obtained through the separately use of stable isotope and DNA data suggested some degree of differences in prey assimilation (stable isotope and digestion rates (DNA analysis. In contrast, combined posterior isotope mixing model with DNA Bayesian priors provided the closest match to the true diet. We provided the first evidence suggesting that the combined use of these complementary techniques may provide better estimates of the actual diet of top marine predators- a powerful tool in applied ecology in the search for the true consumed diet.

Late Carboniferous to Late Permian carbon isotope stratigraphy

DEFF Research Database (Denmark)

Buggisch, Werner; Krainer, Karl; Schaffhauser, Maria

2015-01-01

An integrated study of the litho-, bio-, and isotope stratigraphy of carbonates in the Southern Alps was undertaken in order to better constrain δ13C variations during the Late Carboniferous to Late Permian. The presented high resolution isotope curves are based on 1299 δ13Ccarb and 396 δ13Corg...

Some directions in ecological theory.

Science.gov (United States)

Kendall, Bruce E

2015-12-01

The role of theory within ecology has changed dramatically in recent decades. Once primarily a source of qualitative conceptual framing, ecological theories and models are now often used to develop quantitative explanations of empirical patterns and to project future dynamics of specific ecological systems. In this essay, I recount my own experience of this transformation, in which accelerating computing power and the widespread incorporation of stochastic processes into ecological theory combined to create some novel integration of mathematical and statistical models. This stronger integration drives theory towards incorporating more biological realism, and I explore ways in which we can grapple with that realism to generate new general theoretical insights. This enhanced realism, in turn, may lead to frameworks for projecting ecological responses to anthropogenic change, which is, arguably, the central challenge for 21st-century ecology. In an era of big data and synthesis, ecologists are increasingly seeking to infer causality from observational data; but conventional biometry provides few tools for this project. This is a realm where theorists can and should play an important role, and I close by pointing towards some analytical and philosophical approaches developed in our sister discipline of economics that address this very problem. While I make no grand prognostications about the likely discoveries of ecological theory over the coming century, you will find in this essay a scattering of more or less far-fetched ideas that I, at least, think are interesting and (possibly) fruitful directions for our field.

Integrating tidal and nontidal ecological assessments

Science.gov (United States)

Mark Southerland; Roberto Llanso

2016-01-01

The Maryland Department of Natural Resources (DNR) has a long history of conducting rigorous assessments of ecological conditions in both tidal and nontidal waters. The Long-Term Benthic (LTB) Monitoring Program and the Maryland Biological Stream Survey (MBSS) both use reference-based indicators of benthic invertebrate communities to provide areawide estimates of ...

Isotopic depletion with Monte Carlo

International Nuclear Information System (INIS)

Martin, W.R.; Rathkopf, J.A.

1996-06-01

This work considers a method to deplete isotopes during a time- dependent Monte Carlo simulation of an evolving system. The method is based on explicitly combining a conventional estimator for the scalar flux with the analytical solutions to the isotopic depletion equations. There are no auxiliary calculations; the method is an integral part of the Monte Carlo calculation. The method eliminates negative densities and reduces the variance in the estimates for the isotope densities, compared to existing methods. Moreover, existing methods are shown to be special cases of the general method described in this work, as they can be derived by combining a high variance estimator for the scalar flux with a low-order approximation to the analytical solution to the depletion equation

[Measuring water ecological carrying capacity with the ecosystem-service-based ecological footprint (ESEF) method: Theory, models and application].

Science.gov (United States)

Jiao, Wen-jun; Min, Qing-wen; Li, Wen-hua; Fuller, Anthony M

2015-04-01

Integrated watershed management based on aquatic ecosystems has been increasingly acknowledged. Such a change in the philosophy of water environment management requires recognizing the carrying capacity of aquatic ecosystems for human society from a more general perspective. The concept of the water ecological carrying capacity is therefore put forward, which considers both water resources and water environment, connects socio-economic development to aquatic ecosystems and provides strong support for integrated watershed management. In this paper, the authors proposed an ESEF-based measure of water ecological carrying capacity and constructed ESEF-based models of water ecological footprint and capacity, aiming to evaluate water ecological carrying capacity with footprint methods. A regional model of Taihu Lake Basin was constructed and applied to evaluate the water ecological carrying capacity in Changzhou City which located in the upper reaches of the basin. Results showed that human demand for water ecosystem services in this city had exceeded the supply capacity of local aquatic ecosystems and the significant gap between demand and supply had jeopardized the sustainability of local aquatic ecosystems. Considering aqua-product provision, water supply and pollutant absorption in an integrated way, the scale of population and economy aquatic ecosystems in Changzhou could bear only 54% of the current status.

Use of an integrated human health/ecological risk assessment to develop a long-term groundwater/site management plan for a sour gas facility

International Nuclear Information System (INIS)

Swanson, S.M.; Shaw, R.D.; McClymont, G.; Nadeau, S.

1995-01-01

An integrated human health and ecological risk assessment was used to quantify the level of risk associated with the off-site movement of contaminants via groundwater and soils at a medium-sized gas processing facility in southern Alberta. The study incorporated three key aspects: (1) integration; (2) consultation; and, (3) pro-active remedial actions. Integration was complete, beginning with the Problem Formulation stage and progressing through Risk Characterization and Risk Management. This integration was reflected in a multidisciplinary team of hydrogeologists, biologists and human health specialists. Several lessons emerged from the integrated approach: (1) spending 2/3 of the time and resources on Problem Formulation prevented later problems; (2) the different perspectives provided by the various specialists helped reveal the relative importance of pathways and ecological receptors (3) clear, consistent screening procedures for contaminants of concern and receptors were very effective with stakeholders; (4) exposure scenarios that incorporated common-sense situations (although still conservative) contributed to the credibility of the risk analysis; and, (5) an innovative combination of toxicity testing and chemical analysis helped delineate the boundaries of the potentially contaminated area for both human and ecological receptors in a cost effective manner. Consultation included directly affected parties, regulatory personnel and community members. The consultation extended through the project, with key ''buy-in'' points during Problem Formulation and Risk Characterization/Management. Pro-active remedial action included the removal of contaminant sources in the 1980's, a pump-and-treat system and extensive monitoring. These actions showed commitment and set the stage for credible risk-based mitigation and long-term monitoring

Physical and Human Controls on the Carbon Composition of Organic Matter in Tropical Rivers: An Integrated Analysis of Landscape Properties and River Isotopic Composition

Energy Technology Data Exchange (ETDEWEB)

Ballester, M. V.R.; Victoria, R. L.; Krusche, A. V. [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Piracicaba (Brazil); Bernardes, M. [Universidade Federal Fluminense, Rio de Janeiro (Brazil); Neill, C.; Deegan, L. [Marine Biological Laboratory, Woods Hole, MA (United States); Richey, J. E. [University of Washington, Seatle, WA (United States)

2013-05-15

We applied an integrated analysis of landscape properties including soil properties, land cover and riverine isotopic composition. To evaluate physical and human controls on the carbon composition of organic matter in tropical rivers, we applied an integrated analysis of landscape properties including soil properties, land cover and riverine isotopic composition. Our main objective was to establish the relationship between basin attributes and forms, fluxes and composition of dissolved and particulate organic matter in river channels. A physical template was developed as a GIS-based comprehensive tool to support the understanding of the biogeochemistry of the surface waters of two tropical rivers: the Ji-Parana (Western Amazonia) and the Piracicaba (southeastern of Brazil). For each river we divided the basin into drainage units, organized according to river network morphology and degree of land use impact. Each sector corresponded to a sampling point where river isotopic composition was analysed. River sites and basin characteristics were calculated using datasets compiled as layers in ArcGis Geographical Information System and ERDAS-IMAGINE (Image Processing) software. Each delineated drainage area was individually characterized in terms of topography, soils, river network and land use. Carbon stable isotopic composition of dissolved organic matter (DOM) and particulate organic matter (POM) was determined at several sites along the main tributaries and small streams. The effects of land use on fluvial carbon composition were quantified by a linear regression analysis, relating basin cover and river isotopic composition. The results showed that relatively recent land cover changes have already had an impact on the composition of the riverine DOM and POM, indicating that, as in natural ecosystems, vegetation plays a key role in the composition of riverine organic matter in agricultural ecosystems. (author)

Bridging the gap between ecology and spatial planning

NARCIS (Netherlands)

Opdam, P.; Vos, C.C.; Foppen, R.

2002-01-01

Landscapes are studied by pattern (the geographical approach) and by process (the ecological approach within landscape ecology). The future of landscape ecology depends on whether the two approaches can be integrated. We present an approach to bridge the gap between the many detailed process studies

Tuna and dolphin associations in the North-east Atlantic: Evidence of different ecological niches from stable isotope and heavy metal measurements

International Nuclear Information System (INIS)

Das, K.; Lepoint, G.; Loizeau, V.; Debacker, V.; Dauby, P.; Bouquegneau, J.M.

2000-01-01

Associations of tunas and dolphins in the wild are quite frequent events and the question arises how predators requiring similar diet in the same habitat share their environmental resources. As isotopic composition of an animal is related to that of its preys, stable isotope ( 13 C/ 12 C and 15 N/ 14 N) analyses were performed in three predator species from the North-east Atlantic: the striped dolphin, Stenella coeruleoalba, the common dolphin Delphinus delphis and the albacore tuna, Thunnus alalunga, and compared to their previously described stomach content. Heavy metals (Cd, Zn, Cu and Fe) are mainly transferred through the diet and so, have been determined in the tissues of the animals. Tuna muscles display higher δ 15 N than in common and striped dolphins (mean: 11.4 vs. 10.3%o and 10.4%o, respectively) which reflects their higher trophic level nutrition. Higher δ 13 C are found in common (-18.4%o) and striped dolphin (-18.1%o) muscles than in albacore tuna (-19.3%o) probably in relation with its migratory pattern. The most striking feature is the presence of two levels of cadmium concentrations in the livers of the tunas (32 mg kg -1 dry weight (DW) vs. 5 mg kg -1 DW). These two groups also differ by their iron concentrations and their δ 15 N and δ 13 C liver values. These results suggest that in the Biscay Bay, tunas occupy two different ecological niches probably based on different squid inputs in their diet

Mercury bio magnification in the Atlantic spotted dolphin (Stenella frontalis) food chain, using nitrogen stable isotope as an ecological tracer

International Nuclear Information System (INIS)

Kehrig, Helena A; Baptista, Gilberto; Di Beneditto, Ana Paula M; Almeida, Marcelo G; Rezende, Carlos E; Siciliano, Salvatore; De Moura, Jailson F; Moreira, Isabel

2017-01-01

An assessment of mercury (Hg) concentrations and nitrogen stable isotope (δ"1"5N) was conducted in the food chain of the Atlantic spotted dolphin (Stenella frontalis), including phytoplankton, zooplankton, planktivorous fish and its major prey (predatory fish and a single species of cephalopod), that compose a tropical trophic chain of the Brazilian southeastern coast. Tissue concentrations of Hg in a voracious predator fish, the largehead hairtail (Trichiurus lepturus), one of the dolphin's prey, were 9.8 times lower than median concentrations found in dolphin tissues. δ"1"5N values in predatory fish were found to be lower to those of its predator the spotted dolphin. Isotopic data suggested significant differences for ? 15N along the trophic chain, with the top predator (dolphin) exhibiting heavier value, followed by the voracious predator fish and the benthonic carnivorous fish, the whitemouth croaker (Micropogonias furnieri). Phytoplankton displayed the lightest δ"1"5N, followed by zooplankton and the planktophagous fish, the lebranche mullet (Mugil liza). This fish species and the cephalopod showed the lowest median Hg concentration. All links of the entire trophic chain presented trophic transfer of Hg with a biomagnification factor higher than 1. A significant relationship was found between the log Hg concentration and trophic level (TL) of all evaluated species, with a positive slope (β= 0.87). The calculated trophic magnification factor (TMF7.44) indicates that Hg concentration increased per TL, and also that the entire coastal food chain from the South Atlantic Ocean presented a biomagnification power of Hg within a range previously reported for tropical coastal ecosystems. Key words: Marine mammal, coastal aquatic biota, toxic element, biotransference, ecological tracer

Enhanced understanding of ectoparasite: host trophic linkages on coral reefs through stable isotope analysis

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Demopoulos, Amanda W. J.; Sikkel, Paul C.

2015-01-01

Parasitism, although the most common type of ecological interaction, is usually ignored in food web models and studies of trophic connectivity. Stable isotope analysis is widely used in assessing the flow of energy in ecological communities and thus is a potentially valuable tool in understanding the cryptic trophic relationships mediated by parasites. In an effort to assess the utility of stable isotope analysis in understanding the role of parasites in complex coral-reef trophic systems, we performed stable isotope analysis on three common Caribbean reef fish hosts and two kinds of ectoparasitic isopods: temporarily parasitic gnathiids (Gnathia marleyi) and permanently parasitic cymothoids (Anilocra). To further track the transfer of fish-derived carbon (energy) from parasites to parasite consumers, gnathiids from host fish were also fed to captive Pederson shrimp (Ancylomenes pedersoni) for at least 1 month. Parasitic isopods had δ13C and δ15N values similar to their host, comparable with results from the small number of other host–parasite studies that have employed stable isotopes. Adult gnathiids were enriched in 15N and depleted in13C relative to juvenile gnathiids, providing insights into the potential isotopic fractionation associated with blood-meal assimilation and subsequent metamorphosis. Gnathiid-fed Pedersen shrimp also had δ13C values consistent with their food source and enriched in 15N as predicted due to trophic fractionation. These results further indicate that stable isotopes can be an effective tool in deciphering cryptic feeding relationships involving parasites and their consumers, and the role of parasites and cleaners in carbon transfer in coral-reef ecosystems specifically.

Enhanced understanding of ectoparasite–host trophic linkages on coral reefs through stable isotope analysis

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Amanda W.J. Demopoulos

2015-04-01

Full Text Available Parasitism, although the most common type of ecological interaction, is usually ignored in food web models and studies of trophic connectivity. Stable isotope analysis is widely used in assessing the flow of energy in ecological communities and thus is a potentially valuable tool in understanding the cryptic trophic relationships mediated by parasites. In an effort to assess the utility of stable isotope analysis in understanding the role of parasites in complex coral-reef trophic systems, we performed stable isotope analysis on three common Caribbean reef fish hosts and two kinds of ectoparasitic isopods: temporarily parasitic gnathiids (Gnathia marleyi and permanently parasitic cymothoids (Anilocra. To further track the transfer of fish-derived carbon (energy from parasites to parasite consumers, gnathiids from host fish were also fed to captive Pederson shrimp (Ancylomenes pedersoni for at least 1 month. Parasitic isopods had δ13C and δ15N values similar to their host, comparable with results from the small number of other host–parasite studies that have employed stable isotopes. Adult gnathiids were enriched in 15N and depleted in 13C relative to juvenile gnathiids, providing insights into the potential isotopic fractionation associated with blood-meal assimilation and subsequent metamorphosis. Gnathiid-fed Pedersen shrimp also had δ13C values consistent with their food source and enriched in 15N as predicted due to trophic fractionation. These results further indicate that stable isotopes can be an effective tool in deciphering cryptic feeding relationships involving parasites and their consumers, and the role of parasites and cleaners in carbon transfer in coral-reef ecosystems specifically.

Stable isotopes, beaks and predators: a new tool to study the trophic ecology of cephalopods, including giant and colossal squids.

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Cherel, Yves; Hobson, Keith A

2005-08-07

Cephalopods play a key role in the marine environment but knowledge of their feeding habits is limited by lack of data. Here, we have developed a new tool to investigate their feeding ecology by combining the use of their predators as biological samplers together with measurements of the stable isotopic signature of their beaks. Cephalopod beaks are chitinous hard structures that resist digestion and the stable isotope ratios of carbon (delta13C) and nitrogen (delta15N) are indicators of the foraging areas and trophic levels of consumers, respectively. First, a comparison of delta13C and delta15N values of different tissues from the same individuals showed that beaks were slightly enriched in 13C but highly impoverished in 15N compared with lipid-free muscle tissues. Second, beaks from the same species showed a progressive increase in their delta15N values with increasing size, which is in agreement with a dietary shift from lower to higher trophic levels during cephalopod growth. In the same way, there was an increase in the delta15N signature of various parts of the same lower beaks in the order rostrum, lateral walls and wings, which reflects the progressive growth and chitinization of the beaks in parallel with dietary changes. Third, we investigated the trophic structure of a cephalopod community for the first time. Values of delta15N indicate that cephalopods living in slope waters of the subantarctic Kerguelen Islands (n=18 species) encompass almost three distinct trophic levels, with a continuum of two levels between crustacean- and fish-eaters and a distinct higher trophic level occupied by the colossal squid Mesonychoteuthis hamiltoni. delta13C values demonstrated that cephalopods grow in three different marine ecosystems, with 16 species living and developing in Kerguelen waters and two species migrating from either Antarctica (Slosarczykovia circumantarctica) or the subtropics (the giant squid Architeuthis dux). The stable isotopic signature of beaks

The role played by social-ecological resilience as a method of integration in interdisciplinary research

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Simone A. Beichler

2014-09-01

Full Text Available Today's multifaceted environmental problems, including climate change, necessitate interdisciplinary research. It is however difficult to combine disciplines to study such complex phenomena. We analyzed the experience we gained in applying a particular method of interdisciplinary integration, the 'bridging concept.' We outlined the entire process of developing, utilizing, and adapting social-ecological resilience as a bridging concept in a research project involving seven different disciplines. We focused on the tensions and opportunities arising from interdisciplinary dialogue and the understandings and manifestations of resilience in the disciplines involved. By evaluating the specific cognitive and social functions of resilience as a method of integration, we call for placing greater emphasis on the quality and value of the actual interdisciplinary process, rather than concentrating solely on the output of interdisciplinary work.

Integral stormwater management master plan and design in an ecological community.

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Che, Wu; Zhao, Yang; Yang, Zheng; Li, Junqi; Shi, Man

2014-09-01

Urban stormwater runoff nearly discharges directly into bodies of water through gray infrastructure in China, such as sewers, impermeable ditches, and pump stations. As urban flooding, water shortage, and other environment problems become serious, integrated water environment management is becoming increasingly complex and challenging. At more than 200ha, the Oriental Sun City community is a large retirement community located in the eastern side of Beijing. During the beginning of its construction, the project faced a series of serious water environment crises such as eutrophication, flood risk, water shortage, and high maintenance costs. To address these issues, an integral stormwater management master plan was developed based on the concept of low impact development (LID). A large number of LID and green stormwater infrastructure (GSI) approaches were designed and applied in the community to replace traditional stormwater drainage systems completely. These approaches mainly included bioretention (which captured nearly 85th percentile volume of the annual runoff in the site, nearly 5.4×10(5)m(3) annually), swales (which functioned as a substitute for traditional stormwater pipes), waterscapes, and stormwater wetlands. Finally, a stormwater system plan was proposed by integrating with the gray water system, landscape planning, an architectural master plan, and related consultations that supported the entire construction period. After more than 10 years of planning, designing, construction, and operation, Oriental Sun City has become one of the earliest modern large-scale LID communities in China. Moreover, the project not only addressed the crisis efficiently and effectively, but also yielded economic and ecological benefits. Copyright © 2014. Published by Elsevier B.V.

Within-population isotopic niche variability in savanna mammals: disparity between carnivores and herbivores

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Daryl eCodron

2016-02-01

Full Text Available Large mammal ecosystems have relatively simple food webs, usually comprising three – and sometimes only two – trophic links. Since many syntopic species from the same trophic level therefore share resources, dietary niche partitioning features prominently within these systems. In African and other subtropical savannas, stable carbon isotopes readily distinguish between herbivore species for which foliage and other parts of dicot plants (13C-depleted C3 vegetation are the primary resource (browsers and those for which grasses (13C-enriched C4 vegetation are staples (grazers. Similarly, carbon isotopes distinguish between carnivore diets that may be richer in either browser, grazer, or intermediate-feeding prey. Here, we investigate levels of carbon and nitrogen isotopic niche variation and niche partitioning within populations (or species of carnivores and herbivores from South African savannas. We emphasize predictable differences in within-population trends across trophic levels: we expect that herbivore populations, which require more foraging effort due to higher intake requirements, are far less likely to display within-population resource partitioning than carnivore populations. Our results reveal generally narrower isotopic niche breadths in herbivore than carnivore populations, but more importantly we find lower levels of isotopic differentiation across individuals within herbivore species. While these results offer some support for our general hypothesis, the current paucity of isotopic data for African carnivores limits our ability to test the complete set of predictions arising from our hypothesis. Nevertheless, given the different ecological and ecophysiological constraints to foraging behaviour within each trophic level, comparisons across carnivores and herbivores, which are possible within such simplified foodwebs, make these systems ideal for developing a process-based understanding of conditions underlying the evolution of

Isotopic ecology of coyotes from scat and road kill carcasses: A complementary approach to feeding experiments.

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Reid, Rachel E B; Koch, Paul L

2017-01-01

Scat is frequently used to study animal diets because it is easy to find and collect, but one concern is that gross fecal analysis (GFA) techniques exaggerate the importance of small-bodied prey to mammalian mesopredator diets. To capitalize on the benefits of scat, we suggest the analysis of scat carbon and nitrogen isotope values (δ13C and δ15N). This technique offers researchers a non-invasive method to gather short-term dietary information. We conducted three interrelated studies to validate the use of isotopic values from coyote scat: 1) we determined tissue-to-tissue apparent C and N isotope enrichment factors (ε13* and ε15*) for coyotes from road kill animals (n = 4); 2) we derived diet-to-scat isotope discrimination factors for coyotes; and 3) we used field collected coyote scats (n = 12) to compare estimates of coyote dietary proportions from stable isotope mixing models with estimates from two GFA techniques. Scat consistently had the lowest δ13C and δ15N values among the tissues sampled. We derived a diet-to-scat Δ13C value of -1.5‰ ± 1.6‰ and Δ15N value of 2.3‰ ± 1.3‰ for coyotes. Coyote scat δ13C and δ15N values adjusted for discrimination consistently plot within the isotopic mixing space created by known dietary items. In comparison with GFA results, we found that mixing model estimates of coyote dietary proportions de-emphasize the importance of small-bodied prey. Coyote scat δ13C and δ15N values therefore offer a relatively quick and non-invasive way to gain accurate dietary information.

The influence of isotope substitution of neon atom on the integral cross sections of rotational excitation in Ne—Na2 collisions

International Nuclear Information System (INIS)

Zang Hua-Ping; Li Wen-Feng; Linghu Rong-Feng; Cheng Xin-Lu; Yang Xiang-Dong

2011-01-01

This paper applies the multiple ellipsoid model to the 16 Ne ( 20 Ne, 28 Ne, 34 Ne)-Na 2 collision systems, and calculates integral cross sections for rotational excitation at the incident energy of 190 meV. It can be seen that the accuracy of the integral cross sections can be improved by increasing the number of equipotential ellipsoid surfaces. Moreover, by analysing the differences of these integral cross sections, it obtains the change rules of the integral cross sections with the increase of rotational angular quantum number J', and with the change of the mass of isotope substitution neon atom. Finally, the contribution of different regions of the potential to inelastic cross sections for 20 Ne-Na 2 collision system is investigated at relative incident energy of 190 meV. (general)

Calcium isotopes offer clues on resource partitioning among Cretaceous predatory dinosaurs.

Science.gov (United States)

Hassler, A; Martin, J E; Amiot, R; Tacail, T; Godet, F Arnaud; Allain, R; Balter, V

2018-04-11

Large predators are overabundant in mid-Cretaceous continental dinosaur assemblages of North Africa. Such unbalanced ecosystem structure involves, among predatory dinosaurs, typical abelisaurid or carcharodontosaurid theropods co-occurring with long-snouted spinosaurids of debated ecology. Here, we report calcium (Ca) isotope values from tooth enamel (expressed as δ 44/42 Ca) to investigate resource partitioning in mid-Cretaceous assemblages from Niger (Gadoufaoua) and Morocco (Kem Kem Beds). In both assemblages, spinosaurids display a distinct isotopic signature, the most negative in our dataset. This distinct taxonomic clustering in Ca isotope values observed between spinosaurids and other predators provides unambiguous evidence for niche partitioning at the top of the trophic chains: spinosaurids foraged on aquatic environments while abelisaurid and carcharodontosaurid theropods relied almost exclusively on terrestrial resources. © 2018 The Author(s).

Short-term measurement of carbon isotope fractionation in plants

International Nuclear Information System (INIS)

O'Leary, M.H.; Treichel, I.; Rooney, M.

1986-01-01

Combustion-based studies of the carbon-13 content of plants give only an integrated, long-term value for the isotope fractionation associated with photosynthesis. A method is described here which permits determination of this isotope fractionation in 2 to 3 hours. To accomplish this, the plant is enclosed in a glass chamber, and the quantity and isotopic content of the CO 2 remaining in the atmosphere are monitored during photosynthesis. Isotope fractionation studies by this method give results consistent with what is expected from combustion studies of C 3 , C 4 , and Crassulacean acid metabolism plants. This method will make possible a variety of new studies of environmental and species effects in carbon isotope fractionation

Proceedings of the symposium on isotope geology progress: technology, methods, theory and application

International Nuclear Information System (INIS)

2003-11-01

The symposium was held in Beijing, Nov. 7-11, and the proceedings collects 122 articles, the contents include: new technology and new methods on isotopic test; isotope fractionation mechanism; the early evolution of the solar system and the Earth; continental dynamics and evolution of orogenic belts; minerals, energy and water; major history events on life origin, evolution and geology; changes in the Earth's global and modern environment--the oceans, the atmosphere, rivers and lakes, karst and soil, ecological agriculture and modern environment

INTEGRATING SOCIAL, ECONOMIC AND ECOLOGICAL ANALYSIS TO IMPROVE WILDFIRE MANAGEMENT IN THE U.S.: TESTING A NEW ORGANIZING APPROACH FOR ENVIRONMENTAL ASSESSMENT

Science.gov (United States)

Conducting an integrated analysis to evaluate the societal and ecological consequences of environmental management actions requires decisions about data collection, theory development, modeling and valuation. Approaching these decisions in coordinated fashion necessitates a syste...

Distinctive diet-tissue isotopic discrimination factors derived from the exclusive bamboo-eating giant panda.

Science.gov (United States)

Han, Han; Wei, Wei; Nie, Yonggang; Zhou, Wenliang; Hu, Yibo; Wu, Qi; Wei, Fuwen

2016-11-01

Stable isotope analysis is very useful in animal ecology, especially in diet reconstruction and trophic studies. Differences in isotope ratios between consumers and their diet, termed discrimination factors, are essential for studies of stable isotope ecology and are species-specific and tissue-specific. Given the specialized bamboo diet and clear foraging behavior, here, we calculated discrimination factors for carbon and nitrogen isotopes from diet to tissues (tooth enamel, hair keratin and bone collagen) for the giant panda (Ailuropoda melanoleuca), a species derived from meat-eating ancestors. Our results showed that carbon discrimination factor obtained from giant panda tooth enamel (ε 13 C diet-enamel = 10.0‰) and nitrogen discrimination factors from hair keratin (Δ 15 N diet-hair = 2.2‰) and bone collagen (Δ 15 N diet-collagen = 2.3‰) were lower, and carbon discrimination factors from hair keratin (Δ 13 C diet-hair = 5.0‰) and bone collagen (Δ 13 C diet-collagen = 6.1‰) were higher than those of other mammalian carnivores, omnivores and herbivores. Such distinctive values are likely the result of a low-nutrient and specialized bamboo diet, carnivore-like digestive system and exceptionally low metabolism in giant pandas. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Global patterns of foliar nitrogen isotopes and their relationships with climate, mycorrhizal fungi, foliar nutrient concentrations, and nitrogen availability

Science.gov (United States)

Joseph M. Craine; Andrew J. Elmore; Marcos P. M. Aidar; Mercedes Bustamante; Todd E. Dawson; Erik A. Hobbie; Ansgar Kahmen; Michelle C. Mack; Kendra K. McLauchlan; Anders Michelsen; Gabriela Nardoto; Linda H. Pardo; Josep Penuelas; Peter B. Reich; Edward A.G. Schuur; William D. Stock; Pamela H. Templer; Ross A. Virginia; Jeffrey M. Welker; Ian J. Wright

2009-01-01

Ratios of nitrogen (N) isotopes in leaves could elucidate underlying patterns of N cycling across ecological gradients. To better understand global-scale patterns of N cycling, we compiled data on foliar N isotope ratios, foliar N concentrations, mycorrhizal type and climate for over 11 000 plants worldwide. Global-scale comparisons of other components of the N cycle...

Application of Thermoeconomics to Industrial Ecology

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Alicia Valero

2010-03-01

Full Text Available Industrial Ecology involves the transformation of industrial processes from linear to closed loop systems: matter and energy flows which were initially considered as wastes become now resources for existing or new processes. In this paper, Thermoeconomics, commonly used for the optimization and diagnosis of energy systems, is proposed as a tool for the characterization of Industrial Ecology. Thermoeconomics is based on the exergy analysis (Thermodynamics but goes further by introducing the concepts of purpose and cost (Economics. It is presented in this study as a systematic and general approach for the analysis of waste flow integration. The formulation is based on extending the thermoeconomic process of the cost formation of wastes in order to consider their use as input for other processes. Consequently, it can be applied to important Industrial Ecology issues such as identification of integration possibilities and efficiency improvement, quantification of benefits obtained by integration, or determination of fair prices based on physical roots. The capability of the methodology is demonstrated by means of a case study based on the integration of a power plant, a cement kiln and a gas-fired boiler.

Isotopic ecology of coyotes from scat and road kill carcasses: A complementary approach to feeding experiments.

Directory of Open Access Journals (Sweden)

Rachel E B Reid

Full Text Available Scat is frequently used to study animal diets because it is easy to find and collect, but one concern is that gross fecal analysis (GFA techniques exaggerate the importance of small-bodied prey to mammalian mesopredator diets. To capitalize on the benefits of scat, we suggest the analysis of scat carbon and nitrogen isotope values (δ13C and δ15N. This technique offers researchers a non-invasive method to gather short-term dietary information. We conducted three interrelated studies to validate the use of isotopic values from coyote scat: 1 we determined tissue-to-tissue apparent C and N isotope enrichment factors (ε13* and ε15* for coyotes from road kill animals (n = 4; 2 we derived diet-to-scat isotope discrimination factors for coyotes; and 3 we used field collected coyote scats (n = 12 to compare estimates of coyote dietary proportions from stable isotope mixing models with estimates from two GFA techniques. Scat consistently had the lowest δ13C and δ15N values among the tissues sampled. We derived a diet-to-scat Δ13C value of -1.5‰ ± 1.6‰ and Δ15N value of 2.3‰ ± 1.3‰ for coyotes. Coyote scat δ13C and δ15N values adjusted for discrimination consistently plot within the isotopic mixing space created by known dietary items. In comparison with GFA results, we found that mixing model estimates of coyote dietary proportions de-emphasize the importance of small-bodied prey. Coyote scat δ13C and δ15N values therefore offer a relatively quick and non-invasive way to gain accurate dietary information.

Ecological connectivity networks in rapidly expanding cities

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Amal Najihah M. Nor

2017-06-01

Full Text Available Urban expansion increases fragmentation of the landscape. In effect, fragmentation decreases connectivity, causes green space loss and impacts upon the ecology and function of green space. Restoration of the functionality of green space often requires restoring the ecological connectivity of this green space within the city matrix. However, identifying ecological corridors that integrate different structural and functional connectivity of green space remains vague. Assessing connectivity for developing an ecological network by using efficient models is essential to improve these networks under rapid urban expansion. This paper presents a novel methodological approach to assess and model connectivity for the Eurasian tree sparrow (Passer montanus and Yellow-vented bulbul (Pycnonotus goiavier in three cities (Kuala Lumpur, Malaysia; Jakarta, Indonesia and Metro Manila, Philippines. The approach identifies potential priority corridors for ecological connectivity networks. The study combined circuit models, connectivity analysis and least-cost models to identify potential corridors by integrating structure and function of green space patches to provide reliable ecological connectivity network models in the cities. Relevant parameters such as landscape resistance and green space structure (vegetation density, patch size and patch distance were derived from an expert and literature-based approach based on the preference of bird behaviour. The integrated models allowed the assessment of connectivity for both species using different measures of green space structure revealing the potential corridors and least-cost pathways for both bird species at the patch sites. The implementation of improvements to the identified corridors could increase the connectivity of green space. This study provides examples of how combining models can contribute to the improvement of ecological networks in rapidly expanding cities and demonstrates the usefulness of such

Frequency stabilization of quantum cascade laser for spectroscopic CO2 isotope analysis

Science.gov (United States)

Han, Luo; Xia, Hua; Pang, Tao; Zhang, Zhirong; Wu, Bian; Liu, Shuo; Sun, Pengshuai; Cui, Xiaojuan; Wang, Yu; Sigrist, Markus W.; Dong, Fengzhong

2018-06-01

Using off-axis integrated cavity output spectroscopy, named OA-ICOS, the absorption spectrum of CO2 at 4.32 μm is recorded by using a quantum cascade laser (QCL). The concentration of the three isotopologues 16O12C16O, 16O13C16O and 16O12C18O is detected simultaneously. The isotope abundance ratio of 13C and 18O in CO2 gas can be obtained, which is most useful for ecological research. Since the ambient temperature has a serious influence on the output wavelength of the laser, even small temperature variations seriously affect the stability and sensitivity of the system. In this paper, a wavelength locking technique for QCL is proposed. The output of a digital potentiometer integrated in the laser current driver control is modified by software, resulting in a correction of the driving current of the laser and thus of its wavelength. This method strongly reduces the influence of external factors on the wavelength drift of lasers and thus substantially improves the stability and performance of OA-ICOS as is demonstrated with long-time measurements on CO2 in laboratory air.

Defining fish community structure in Lake Winnipeg using stable isotopes (δ13C, δ15N, δ34S): Implications for monitoring ecological responses and trophodynamics of mercury and other trace elements

International Nuclear Information System (INIS)

Ofukany, Amy F.A.; Wassenaar, Leonard I.; Bond, Alexander L.; Hobson, Keith A.

2014-01-01

The ecological integrity of freshwater lakes is influenced by atmospheric and riverine deposition of contaminants, shoreline development, eutrophication, and the introduction of non-native species. Changes to the trophic structure of Lake Winnipeg, Canada, and consequently, the concentrations of contaminants and trace elements measured in tissues of native fishes, are likely attributed to agricultural runoff from the 977,800 km 2 watershed and the arrival of non-native zooplankters and fishes. We measured δ 13 C, δ 15 N, and δ 34 S along with concentrations of 15 trace elements in 17 native fishes from the north and south basins of Lake Winnipeg in 2009 and 2010. After adjusting for differences in isotopic baseline values between the two basins, fishes in the south basin had consistently higher δ 13 C and δ 34 S, and lower δ 15 N. We found little evidence of biomagnification of trace elements at the community level, but walleye (Sander vitreus) and freshwater drum (Aplodinotus grunniens) had higher mercury and selenium concentrations with increased trophic position, coincident with increased piscivory. There was evidence of growth dilution of cobalt, copper, manganese, molybdenum, thallium, and vanadium, and bioaccumulation of mercury, which could be explained by increases in algal (and consequently, lake and fish) productivity. We conclude that the north and south basins of Lake Winnipeg represent very different communities with different trophic structures and trace element concentrations. - Highlights: • Anthropogenic eutrophication and non-native species affect Lake Winnipeg’s ecosystem. • We measured stable isotopes and trace elements in 15 native fish species. • There was more evidence for growth dilution than biomagnification for most elements. • The trophic structures of the north and south basins were different. • These results will help determine the effects of recent arrival of zebra mussels

Terrestrial ecology

International Nuclear Information System (INIS)

Anon.

1977-01-01

The main effort of the Terrestrial Ecology Division has been redirected to a comprehensive study of the Espiritu Santo Drainage Basin located in northeastern Puerto Rico. The general objective are to provide baseline ecological data for future environmental assessment studies at the local and regional levels, and to provide through an ecosystem approach data for the development of management alternatives for the wise utilization of energy, water, and land resources. The interrelationships among climate, vegetation, soils, and man, and their combined influence upon the hydrologic cycle will be described and evaluated. Environmental management involves planning and decision making, and both require an adequate data base. At present, little is known about the interworkings of a complete, integrated system such as a drainage basin. A literature survey of the main research areas confirmed that, although many individual ecologically oriented studies have been carried out in a tropical environment, few if any provide the data base required for environmental management. In view of rapidly changing socio-economic conditions and natural resources limitations, management urgently requires data from these systems: physical (climatological), biological, and cultural. This integrated drainage basin study has been designed to provide such data. The scope of this program covers the hydrologic cycle as it is affected by the interactions of the physical, biological, and cultural systems

Fossil isotope records of seasonal climate and ecology: Straight from the horse's mouth

Science.gov (United States)

Sharp, Z. D.; Cerling, T. E.

1998-03-01

Isotope analysis of a bulk fossil tooth gives a “snapshot” impression of paleoclimatic conditions—a single point in time. However, hypsodont teeth grow over a period of a year or more, so that stable carbon and oxygen isotope variations along their length are a “tape recorder” of short-term seasonal variations from the distant past. We have used a new in situ micro-laser sampling method to determine submillimeter carbon and oxygen isotope variations in the enamel of individual fossil horse teeth to assess ancient annual meteoric water variations and feeding patterns. The δ18O values from a 6.8 Ma fossil horse tooth (Astrohippus ansae) from Texas vary cyclically along the 6 cm length of the tooth with a smoothed amplitude of >4‰, similar to the monthly averaged amplitude measured in modern meteoric waters from the region. The seasonal δ18O values are ˜3‰ to 4‰ higher than those calculated from modern meteoric water data, suggesting either a higher local meteoric water value in the Miocene of Texas, or that the animal received a high proportion of its dietary water from plants or highly evaporated water. A Holocene horse tooth from the shores of Glacial Lake Agassiz, North Dakota (Equus sp.), also has isotopic variations with the same 35 mm periodicity, but a smoothed amplitude of only 2‰. This horse most likely had a buffered drinking supply. The calculated δ18O of the water in equilibrium with this tooth is the same as the modern measured annual average. The variations within a single tooth can be as large as those generally observed in entire stratigraphic sections of fossil teeth analyzed by bulk methods. The new method provides an important technique for evaluating fossil diagenesis; conventional bulk analyses of teeth fragments may not be representative of the whole tooth, thus explaining analytical scatter that has been previously attributed to diagenesis.

Conservation Biology and Traditional Ecological Knowledge: Integrating Academic Disciplines for Better Conservation Practice

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Joshua A. Drew

2006-12-01

Full Text Available Conservation biology and environmental anthropology are disciplines that are both concerned with the identification and preservation of diversity, in one case biological and in the other cultural. Both conservation biology and the study of traditional ecoloigcal knowledge function at the nexus of the social and natural worlds, yet historically there have been major impediments to integrating the two. Here we identify linguistic, cultural, and epistemological barriers between the two disciplines. We argue that the two disciplines are uniquely positioned to inform each other and to provide critical insights and new perspectives on the way these sciences are practiced. We conclude by synthesizing common themes found in conservation success stories, and by making several suggestions on integration. These include cross-disciplinary publication, expanding memberships in professional societies and conducting multidisciplinary research based on similar interests in ecological process, taxonomy, or geography. Finally, we argue that extinction threats, be they biological or cultural/linguistic are imminent, and that by bringing these disciplines together we may be able to forge synergistic conservation programs capable of protecting the vivid splendor of life on Earth.

Using ecological indicators and a decision support system for integrated ecological assessment at two national park units in the Mid-Atlantic region, U.S.A.

Science.gov (United States)

Mahan, Carolyn G.; Young, John A.; Miller, Bruce; Saunders, Michael C.

2014-01-01

We implemented an integrated ecological assessment using a GIS-based decision support system model for Upper Delaware Scenic and Recreational River (UPDE) and Delaware Water Gap National Recreation Area (DEWA)—national park units with the mid-Atlantic region of the United States. Our assessment examined a variety of aquatic and terrestrial indicators of ecosystem components that reflect the parks’ conservation purpose and reference condition. Our assessment compared these indicators to ecological thresholds to determine the condition of park watersheds. Selected indicators included chemical and physical measures of water quality, biologic indicators of water quality, and landscape condition measures. For the chemical and physical measures of water quality, we used a water quality index and each of its nine components to assess the condition of water quality in each watershed. For biologic measures of water quality, we used the Ephemeroptera, Plecoptera, Trichoptera aquatic macroinvertebrate index and, secondarily, the Hilsenhoff aquatic macroinvertebrate index. Finally, for the landscape condition measures of our model, we used percent forest and percent impervious surface. Based on our overall assessment, UPDE and DEWA watersheds had an ecological assessment score of 0.433 on a −1 to 1 fuzzy logic scale. This score indicates that, in general, the natural resource condition within watersheds at these parks is healthy or ecologically unimpaired; however, we had only partial data for many of our indicators. Our model is iterative and new data may be incorporated as they become available. These natural parks are located within a rapidly urbanizing landscape—we recommend that natural resource managers remain vigilant to surrounding land uses that may adversely affect natural resources within the parks.

Beyond diet reconstruction: stable isotope applications to human physiology, health, and nutrition.

Science.gov (United States)

Reitsema, Laurie J

2013-01-01

Analysis of stable carbon and nitrogen isotopes from soft or mineralized tissues is a direct and widely-used technique for modeling diets. In addition to its continued role in paleodiet analysis, stable isotope analysis is now contributing to studies of physiology, disease, and nutrition in archaeological and living human populations. In humans and other animals, dietary uptake and distribution of carbon and nitrogen among mineralized and soft tissue is carried out with varying efficiency due to factors of internal biology. Human pathophysiologies may lead to pathology-influenced isotopic fractionation that can be exploited to understand not just skeletal health and diet, but physiological health and nutrition. This study reviews examples from human biology, non-human animal ecology, biomedicine, and bioarchaeology demonstrating how stable isotope analyses are usefully applied to the study of physiological adaptation and adaptability. Suggestions are made for future directions in applying stable isotope analysis to the study of nutritional stress, disease, and growth and development in living and past human populations. Copyright © 2013 Wiley Periodicals, Inc.

"We Like to Listen to Stories about Fish": Integrating Indigenous Ecological and Scientific Knowledge to Inform Environmental Flow Assessments

Directory of Open Access Journals (Sweden)

Sue E. Jackson

2014-03-01

Full Text Available Studies that apply indigenous ecological knowledge to contemporary resource management problems are increasing globally; however, few of these studies have contributed to environmental water management. We interviewed three indigenous landowning groups in a tropical Australian catchment subject to increasing water resource development pressure and trialed tools to integrate indigenous and scientific knowledge of the biology and ecology of freshwater fish to assess their water requirements. The differences, similarities, and complementarities between the knowledge of fish held by indigenous people and scientists are discussed in the context of the changing socioeconomic circumstances experienced by indigenous communities of north Australia. In addition to eliciting indigenous knowledge that confirmed field fish survey results, the approach generated knowledge that was new to both science and indigenous participants, respectively. Indigenous knowledge influenced (1 the conceptual models developed by scientists to understand the flow ecology and (2 the structure of risk assessment tools designed to understand the vulnerability of particular fish to low-flow scenarios.

[Political ecology, ecological economics, and public health: interfaces for the sustainability of development and health promotion].

Science.gov (United States)

Porto, Marcelo Firpo; Martinez-Alier, Joan

2007-01-01

This article proposes to focus contributions from political ecology and ecological economics to the field of collective health with a view towards integrating the discussions around health promotion, socio-environmental sustainability, and development. Ecological economics is a recent interdisciplinary field that combines economists and other professionals from the social, human, and life sciences. The field has developed new concepts and methodologies that seek to grasp the relationship between the economy and ecological and social processes such as social metabolism and metabolic profile, thereby interrelating economic, material, and energy flows and producing indicators and indexes for (un)sustainability. Meanwhile, political ecology approaches ecological issues and socio-environmental conflicts based on the economic and power dynamics characterizing modern societies. Collective health and the discussions on health promotion can expand our understanding of territory, communities, and the role of science and institutions based on the contributions of political ecology and ecological economics in analyzing development models and the distributive and socio-environmental conflicts generated by them.

Landscape ecology: what is the state of science?

Science.gov (United States)

Monica G. Turner

2005-01-01

Landscape ecology focuses on the reciprocal interactions between spatial pattern and ecological processes, and it is well integrated with ecology. The field has grown rapidly over the past 15 years. The persistent influence of land-use history and natural disturbance on contemporary ecosystems has become apparent Development of pattern metrics has largely stabilized,...

The isotopic composition of soil organic carbon on a north - south transect in western Canada

Czech Academy of Sciences Publication Activity Database

Bird, M.; Šantrůčková, Hana; Lloyd, J.; Lawson, E.

2002-01-01

Roč. 53, - (2002), s. 393-403 ISSN 1351-0754 Institutional research plan: CEZ:AV0Z6066911 Keywords : isotopic composition * soil organic carbon * western Canada Subject RIV: EH - Ecology, Behaviour Impact factor: 1.452, year: 2002

Integrating research tools to support the management of social-ecological systems under climate change

Science.gov (United States)

Miller, Brian W.; Morisette, Jeffrey T.

2014-01-01

Developing resource management strategies in the face of climate change is complicated by the considerable uncertainty associated with projections of climate and its impacts and by the complex interactions between social and ecological variables. The broad, interconnected nature of this challenge has resulted in calls for analytical frameworks that integrate research tools and can support natural resource management decision making in the face of uncertainty and complex interactions. We respond to this call by first reviewing three methods that have proven useful for climate change research, but whose application and development have been largely isolated: species distribution modeling, scenario planning, and simulation modeling. Species distribution models provide data-driven estimates of the future distributions of species of interest, but they face several limitations and their output alone is not sufficient to guide complex decisions for how best to manage resources given social and economic considerations along with dynamic and uncertain future conditions. Researchers and managers are increasingly exploring potential futures of social-ecological systems through scenario planning, but this process often lacks quantitative response modeling and validation procedures. Simulation models are well placed to provide added rigor to scenario planning because of their ability to reproduce complex system dynamics, but the scenarios and management options explored in simulations are often not developed by stakeholders, and there is not a clear consensus on how to include climate model outputs. We see these strengths and weaknesses as complementarities and offer an analytical framework for integrating these three tools. We then describe the ways in which this framework can help shift climate change research from useful to usable.

Improving the integration of recreation management with management of other natural resources by applying concepts of scale from ecology

Science.gov (United States)

Wayde c. Morse; Troy E. Hall; Linda E. Kruger

2008-01-01

In this article, we examine how issues of scale affect the integration of recreation management with the management of other natural resources on public lands. We present two theories used to address scale issues in ecology and explore how they can improve the two most widely applied recreation-planning frameworks. The theory of patch dynamics and hierarchy theory are...

Interpreting the process behind endemism in China by integrating the phylogeography and ecological niche models of the Stachyridopsis ruficeps.

Directory of Open Access Journals (Sweden)

Huatao Liu

Full Text Available An area of endemism (AOE is a complex expression of the ecological and evolutionary history of a species. Here we aim to address the principal drivers of avian diversification in shaping patterns of endemism in China by integrating genetic, ecological, and distributional data on the Red-headed Tree Babbler (Stachyridopsis ruficeps, which is distributed across the eastern Himalayas and south China. We sequenced two mtDNA markers from 182 individuals representing all three of the primary AOEs in China. Phylogenetic inferences were used to reconstruct intraspecific phylogenetic relationships. Divergence time and population demography were estimated to gain insight into the evolutionary history of the species. We used Ecological niche modeling to predict species' distributions during the Last Glacial Maximum (LGM and in the present. Finally, we also used two quantitative tests, an identity test and background test to assess the similarity of ecological niche preferences between adjacent lineages. We found five primary reciprocally monophyletic clades, typically separated approximately 0.2-2.27 MYA, of which three were deeply isolated endemic lineages located in the three AOEs. All phylogroups were detected to have undergone population expansion during the past 0.3 MY. Niche models showed discontinuous habitats, and there were three barriers of less suitable habitat during the LGM and in modern times. Ecoclimatic niches may diverge significantly even over recent timescales, as each phylogroup had a unique distribution, and unique niche characteristics. Vicariant events associated with geographical and ecological barriers, glacial refuges and ecological differentiation may be the main drivers forming the pattern of endemism in China.

Modelling dendritic ecological networks in space: An integrated network perspective

Science.gov (United States)

Erin E. Peterson; Jay M. Ver Hoef; Dan J. Isaak; Jeffrey A. Falke; Marie-Josee Fortin; Chris E. Jordan; Kristina McNyset; Pascal Monestiez; Aaron S. Ruesch; Aritra Sengupta; Nicholas Som; E. Ashley Steel; David M. Theobald; Christian E. Torgersen; Seth J. Wenger

2013-01-01

Dendritic ecological networks (DENs) are a unique form of ecological networks that exhibit a dendritic network topology (e.g. stream and cave networks or plant architecture). DENs have a dual spatial representation; as points within the network and as points in geographical space. Consequently, some analytical methods used to quantify relationships in other types of...

International symposium on isotope hydrology and integrated water resources management. Book of extended synopses

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

Scarcity of freshwater, degradation of its quality, and increasing demand has motivated ongoing concern in the international community for more effective utilization of freshwater resources. The IAEA's symposia on the use of isotope techniques in water resources development and management have become a recurrent event held every four years. They have provided an international forum for a comprehensive review of the present state-of-the-art and recent advances made in this specific field as well as a basis for delineation of further research and development needs. The year 2003 marks the 40th anniversary of the first IAEA water resources symposium. Increasing use of isotope techniques over the past four decades, in part due to efforts of IAEA, has enhanced availability and effective use of isotopes to address water resources management issues. The Symposium covers a multi-disciplinary spectrum of research and applications of isotope techniques. The participation of isotope specialists, hydrologists, hydrogeologists, geochemists, environmental scientists and water managers is welcomed. The Organizers further encourage the participation and contribution of graduate students in these fields. The major areas covered include: Water cycle processes in the atmosphere and hydrosphere, including surface water, groundwater, and watershed-based studies, age dating of young groundwaters, water, carbon and nutrient cycling processes at the land-ocean-atmosphere interface, recent advances in analytical techniques for isotope hydrology and field applications of isotopes in groundwater or surface water resources management. This book of synopses covers oral presentations and poster sessions.

Analysis of growth and tissue replacement rates by stable sulfur isotope turnover.

Science.gov (United States)

Arneson, L. S.; Macko, S. A.; Macavoy, S. E.

2003-12-01

Stable isotope analysis has become a powerful tool to study animal ecology. Analysis of stable isotope ratios of elements such as carbon, nitrogen, sulfur, hydrogen, oxygen and others have been used to trace migratory routes, reconstruct dietary sources and determine the physiological condition of individual animals. The isotopes most commonly used are carbon, due to differential carbon fractionation in C3 and C4 plants, and nitrogen, due to the approximately 3% enrichment in 15N per trophic level. Although all cells express sulfur-containing compounds, such as cysteine, methionine, and coenzyme A, the turnover rate of sulfur in tissues has not been examined in most studies, owing to the difficulty in determining the δ 34S signature. In this study, we have assessed the rate of sulfur isotopic turnover in mouse tissues following a diet change from terrestrial (7%) to marine (19%) source. Turnover models reflecting both growth rate and metabolic tissue replacement will be developed for blood, liver, fat and muscle tissues.

Stable Isotope Mapping of Alaskan Grasses and Marijuana

Science.gov (United States)

Booth, A. L.; Wooller, M. J.

2008-12-01

The spatial variation of isotope signatures in organic material is a useful forensic tool, particularly when applied to the task of tracking the production and distribution of plant-derived illicit drugs. In order to identify the likely grow-locations of drugs such as marijuana from unknown locations (i.e., confiscated during trafficking), base isotope maps are needed that include measurements of plants from known grow-locations. This task is logistically challenging in remote, large regions such as Alaska. We are therefore investigating the potential of supplementing our base (marijuana) isotope maps with data derived from other plants from known locations and with greater spatial coverage in Alaska. These currently include >150 samples of modern C3 grasses (Poaceae) as well as marijuana samples (n = 18) from known grow-locations across the state. We conducted oxygen, carbon and nitrogen stable isotope analyses of marijuana and grasses (Poaceae). Poaceae samples were obtained from the University of Alaska Fairbanks (UAF) Museum of the North herbarium collection, originally collected by field botanists from around Alaska. Results indicate that the oxygen isotopic composition of these grasses range from 10‰ to 30‰, and broadly mirror the spatial pattern of water isotopes in Alaska. Our marijuana samples were confiscated around the state of Alaska and supplied to us by the UAF Police Department. δ13C, δ15N and δ18O values exhibit geographic patterns similar to the modern grasses, but carbon and nitrogen isotopes of some marijuana plants appear to be influenced by additional factors related to indoor growing conditions (supplementary CO2 sources and the application of organic fertilizer). As well as providing a potential forensic resource, our Poaceae isotope maps could serve additional value by providing resources for studying ecosystem nutrient cycling, for tracing natural ecological processes (i.e., animal migration and food web dynamics) and providing

Identification of volatile and semivolatile compounds in chemical ionization GC-MS using a mass-to-structure (MTS) Search Engine with integral isotope pattern ranking.

Science.gov (United States)

Liao, Wenta; Draper, William M

2013-02-21

The mass-to-structure or MTS Search Engine is an Access 2010 database containing theoretical molecular mass information for 19,438 compounds assembled from common sources such as the Merck Index, pesticide and pharmaceutical compilations, and chemical catalogues. This database, which contains no experimental mass spectral data, was developed as an aid to identification of compounds in atmospheric pressure ionization (API)-LC-MS. This paper describes a powerful upgrade to this database, a fully integrated utility for filtering or ranking candidates based on isotope ratios and patterns. The new MTS Search Engine is applied here to the identification of volatile and semivolatile compounds including pesticides, nitrosoamines and other pollutants. Methane and isobutane chemical ionization (CI) GC-MS spectra were obtained from unit mass resolution mass spectrometers to determine MH(+) masses and isotope ratios. Isotopes were measured accurately with errors of Search Engine and details performance testing with over 50 model compounds.

Sensitivity of reactor integral parameters to #betta##betta# parameter of resolved resonances of fertile isotopes and to the α values, in thermal and epithermal spectra

International Nuclear Information System (INIS)

Barroso, D.E.G.

1982-01-01

A sensitivity analysis of reactor integral parameter to more 10% variation in the resolved resonance parameters #betta##betta# of the fertile isotope and the variations of more 10% in the α values (#betta# sub(#betta#)/#betta# sub(f)) of fissile isotopes of PWR fuel elements, is done. The analysis is made with thermal and epithermal spectra, those last generated in a fuel cell with low V sub(M)/V sub(F). The HAMMER system, the interface programs HELP and LITHE and the HAMMER computer codes, were used as a base for this study. (E.G.) [pt

Intrapopulation variability shaping isotope discrimination and turnover: experimental evidence in arctic foxes.

Directory of Open Access Journals (Sweden)

Nicolas Lecomte

Full Text Available Tissue-specific stable isotope signatures can provide insights into the trophic ecology of consumers and their roles in food webs. Two parameters are central for making valid inferences based on stable isotopes, isotopic discrimination (difference in isotopic ratio between consumer and its diet and turnover time (renewal process of molecules in a given tissue usually measured when half of the tissue composition has changed. We investigated simultaneously the effects of age, sex, and diet types on the variation of discrimination and half-life in nitrogen and carbon stable isotopes (δ¹⁵N and δ¹³C, respectively in five tissues (blood cells, plasma, muscle, liver, nail, and hair of a top predator, the arctic fox Vulpes lagopus.We fed 40 farmed foxes (equal numbers of adults and yearlings of both sexes with diet capturing the range of resources used by their wild counterparts. We found that, for a single species, six tissues, and three diet types, the range of discrimination values can be almost as large as what is known at the scale of the whole mammalian or avian class. Discrimination varied depending on sex, age, tissue, and diet types, ranging from 0.3‰ to 5.3‰ (mean  = 2.6‰ for δ¹⁵N and from 0.2‰ to 2.9‰ (mean  = 0.9‰ for δ¹³C. We also found an impact of population structure on δ¹⁵N half-life in blood cells. Varying across individuals, δ¹⁵N half-life in plasma (6 to 10 days was also shorter than for δ¹³C (14 to 22 days, though δ¹⁵N and δ¹³C half-lives are usually considered as equal.Overall, our multi-factorial experiment revealed that at least six levels of isotopic variations could co-occur in the same population. Our experimental analysis provides a framework for quantifying multiple sources of variation in isotopic discrimination and half-life that needs to be taken into account when designing and analysing ecological field studies.

Transformation of chlorpyrifos in integrated recirculating constructed wetlands (IRCWs) as revealed by compound-specific stable isotope (CSIA) and microbial community structure analysis.

Science.gov (United States)

Tang, Xiaoyan; Yang, Yang; Huang, Wenda; McBride, Murray B; Guo, Jingjing; Tao, Ran; Dai, Yunv

2017-06-01

Carbon isotope analysis and 454 pyrosequencing methods were used to investigate in situ biodegradation of chlorpyrifos during its transport through three model integrated recirculating constructed wetlands (IRCWs). Results show that plant and Fe-impregnated biochar promoted degradation of chlorpyrifos and its metabolite 3,5,6-trichloro-2-pyridinol (TCP). Carbon isotope ratios in the IRCWs shifted to -31.24±0.58‰ (IRCW1, plant free), -26.82±0.60‰ (IRCW2, with plant) and -24.76±0.94‰ (IRCW3, with plant and Fe-biochar). The enrichment factors (Ɛ bulk,c ) were determined as -0.69±0.06‰ (IRCW1), -0.91±0.07‰ (IRCW2) and -1.03±0.09‰ (IRCW3). Microbial community analysis showed that IRCW3 was dominated by members of Bacillus, which can utilize and degrade chlorpyrifos. These results reveal that plant and Fe-biochar can induce carbon isotope fractionation and have a positive impact on the chlorpyrifos degradation efficiency by influencing the development of beneficial microbial communities. Copyright © 2017. Published by Elsevier Ltd.

A protocol for pressurized liquid extraction and processing methods to isolate modern and ancient bone cholesterol for compound-specific stable isotope analysis.

Science.gov (United States)

Laffey, Ann O; Krigbaum, John; Zimmerman, Andrew R

2017-02-15

Bone lipid compound-specific isotope analysis (CSIA) and bone collagen and apatite stable isotope ratio analysis are important sources of ecological and paleodietary information. Pressurized liquid extraction (PLE) is quicker and utilizes less solvent than traditional methods of lipid extraction such as soxhlet and ultrasonication. This study facilitates dietary analysis by optimizing and testing a standardized methodology for PLE of bone cholesterol. Modern and archaeological bones were extracted by PLE using varied temperatures, solvent solutions, and sample weights. The efficiency of PLE was assessed via quantification of cholesterol yields. Stable isotopic ratio integrity was evaluated by comparing isotopic signatures (δ 13 C and δ 18 O values) of cholesterol derived from whole bone, bone collagen and bone apatite. Gas chromatography/mass spectrometry (GC/MS) and gas chromatography isotope ratio mass spectrometry (GC/IRMS) were conducted on purified collagen and lipid extracts to assess isotopic responses to PLE. Lipid yield was optimized at two PLE extraction cycles of 75 °C using dichloromethane/methanol (2:1 v/v) as a solvent with 0.25-0.75 g bone sample. Following lipid extraction, saponification combined with the derivatization of the neutral fraction using trimethylsilylation yielded nearly twice the cholesterol of non-saponified or non-derivatized samples. It was also found that lipids extracted from purified bone collagen and apatite could be used for cholesterol CSIA. There was no difference in the bulk δ 13 C values of collagen extracted from bone with or without lipid. However, there was a significant depletion in 18 O of bone apatite due to lipid presence or processing. These results should assist sample selection and provide an effective, alternative extraction method for bone cholesterol that may be used for isotopic and paleodietary analysis. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Managing consequences of climate-driven species redistribution requires integration of ecology, conservation and social science.

Science.gov (United States)

Bonebrake, Timothy C; Brown, Christopher J; Bell, Johann D; Blanchard, Julia L; Chauvenet, Alienor; Champion, Curtis; Chen, I-Ching; Clark, Timothy D; Colwell, Robert K; Danielsen, Finn; Dell, Anthony I; Donelson, Jennifer M; Evengård, Birgitta; Ferrier, Simon; Frusher, Stewart; Garcia, Raquel A; Griffis, Roger B; Hobday, Alistair J; Jarzyna, Marta A; Lee, Emma; Lenoir, Jonathan; Linnetved, Hlif; Martin, Victoria Y; McCormack, Phillipa C; McDonald, Jan; McDonald-Madden, Eve; Mitchell, Nicola; Mustonen, Tero; Pandolfi, John M; Pettorelli, Nathalie; Possingham, Hugh; Pulsifer, Peter; Reynolds, Mark; Scheffers, Brett R; Sorte, Cascade J B; Strugnell, Jan M; Tuanmu, Mao-Ning; Twiname, Samantha; Vergés, Adriana; Villanueva, Cecilia; Wapstra, Erik; Wernberg, Thomas; Pecl, Gretta T

2018-02-01

Climate change is driving a pervasive global redistribution of the planet's species. Species redistribution poses new questions for the study of ecosystems, conservation science and human societies that require a coordinated and integrated approach. Here we review recent progress, key gaps and strategic directions in this nascent research area, emphasising emerging themes in species redistribution biology, the importance of understanding underlying drivers and the need to anticipate novel outcomes of changes in species ranges. We highlight that species redistribution has manifest implications across multiple temporal and spatial scales and from genes to ecosystems. Understanding range shifts from ecological, physiological, genetic and biogeographical perspectives is essential for informing changing paradigms in conservation science and for designing conservation strategies that incorporate changing population connectivity and advance adaptation to climate change. Species redistributions present challenges for human well-being, environmental management and sustainable development. By synthesising recent approaches, theories and tools, our review establishes an interdisciplinary foundation for the development of future research on species redistribution. Specifically, we demonstrate how ecological, conservation and social research on species redistribution can best be achieved by working across disciplinary boundaries to develop and implement solutions to climate change challenges. Future studies should therefore integrate existing and complementary scientific frameworks while incorporating social science and human-centred approaches. Finally, we emphasise that the best science will not be useful unless more scientists engage with managers, policy makers and the public to develop responsible and socially acceptable options for the global challenges arising from species redistributions. © 2017 Cambridge Philosophical Society.

Ecological connectivity networks in rapidly expanding cities.

Science.gov (United States)

Nor, Amal Najihah M; Corstanje, Ron; Harris, Jim A; Grafius, Darren R; Siriwardena, Gavin M

2017-06-01

Urban expansion increases fragmentation of the landscape. In effect, fragmentation decreases connectivity, causes green space loss and impacts upon the ecology and function of green space. Restoration of the functionality of green space often requires restoring the ecological connectivity of this green space within the city matrix. However, identifying ecological corridors that integrate different structural and functional connectivity of green space remains vague. Assessing connectivity for developing an ecological network by using efficient models is essential to improve these networks under rapid urban expansion. This paper presents a novel methodological approach to assess and model connectivity for the Eurasian tree sparrow ( Passer montanus ) and Yellow-vented bulbul ( Pycnonotus goiavier ) in three cities (Kuala Lumpur, Malaysia; Jakarta, Indonesia and Metro Manila, Philippines). The approach identifies potential priority corridors for ecological connectivity networks. The study combined circuit models, connectivity analysis and least-cost models to identify potential corridors by integrating structure and function of green space patches to provide reliable ecological connectivity network models in the cities. Relevant parameters such as landscape resistance and green space structure (vegetation density, patch size and patch distance) were derived from an expert and literature-based approach based on the preference of bird behaviour. The integrated models allowed the assessment of connectivity for both species using different measures of green space structure revealing the potential corridors and least-cost pathways for both bird species at the patch sites. The implementation of improvements to the identified corridors could increase the connectivity of green space. This study provides examples of how combining models can contribute to the improvement of ecological networks in rapidly expanding cities and demonstrates the usefulness of such models for

Stable isotope study of a new chondrichthyan fauna (Kimmeridgian, Porrentruy, Swiss Jura): an unusual freshwater-influenced isotopic composition for the hybodont shark Asteracanthus

Science.gov (United States)

Leuzinger, L.; Kocsis, L.; Billon-Bruyat, J.-P.; Spezzaferri, S.; Vennemann, T.

2015-12-01

Chondrichthyan teeth (sharks, rays, and chimaeras) are mineralized in isotopic equilibrium with the surrounding water, and parameters such as water temperature and salinity can be inferred from the oxygen isotopic composition (δ18Op) of their bioapatite. We analysed a new chondrichthyan assemblage, as well as teeth from bony fish (Pycnodontiformes). All specimens are from Kimmeridgian coastal marine deposits of the Swiss Jura (vicinity of Porrentruy, Ajoie district, NW Switzerland). While the overall faunal composition and the isotopic composition of bony fish are generally consistent with marine conditions, unusually low δ18Op values were measured for the hybodont shark Asteracanthus. These values are also lower compared to previously published data from older European Jurassic localities. Additional analyses on material from Solothurn (Kimmeridgian, NW Switzerland) also have comparable, low-18O isotopic compositions for Asteracanthus. The data are hence interpreted to represent a so far unique, freshwater-influenced isotopic composition for this shark that is classically considered a marine genus. While reproduction in freshwater or brackish realms is established for other hybodonts, a similar behaviour for Asteracanthus is proposed here. Regular excursions into lower salinity waters can be linked to the age of the deposits and correspond to an ecological adaptation, most likely driven by the Kimmeridgian transgression and by the competition of the hybodont shark Asteracanthus with the rapidly diversifying neoselachians (modern sharks).

Putative bacterial interactions from metagenomic knowledge with an integrative systems ecology approach.

Science.gov (United States)

Bordron, Philippe; Latorre, Mauricio; Cortés, Maria-Paz; González, Mauricio; Thiele, Sven; Siegel, Anne; Maass, Alejandro; Eveillard, Damien

2016-02-01

Following the trend of studies that investigate microbial ecosystems using different metagenomic techniques, we propose a new integrative systems ecology approach that aims to decipher functional roles within a consortium through the integration of genomic and metabolic knowledge at genome scale. For the sake of application, using public genomes of five bacterial strains involved in copper bioleaching: Acidiphilium cryptum, Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferriphilum, and Sulfobacillus thermosulfidooxidans, we first reconstructed a global metabolic network. Next, using a parsimony assumption, we deciphered sets of genes, called Sets from Genome Segments (SGS), that (1) are close on their respective genomes, (2) take an active part in metabolic pathways and (3) whose associated metabolic reactions are also closely connected within metabolic networks. Overall, this SGS paradigm depicts genomic functional units that emphasize respective roles of bacterial strains to catalyze metabolic pathways and environmental processes. Our analysis suggested that only few functional metabolic genes are horizontally transferred within the consortium and that no single bacterial strain can accomplish by itself the whole copper bioleaching. The use of SGS pinpoints a functional compartmentalization among the investigated species and exhibits putative bacterial interactions necessary for promoting these pathways. © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Research on the integration of teaching content of core courses in Agro-ecological environmental specialties of higher vocational colleges

Science.gov (United States)

Chen, Juan; Ma, Guosheng

2018-02-01

Curriculum is the means to cultivate higher vocational talents. On the basis of analyzing the core curriculum problems of curriculum reform and Agro-ecological environmental specialties in higher vocational colleges, this paper puts forward the optimization and integration measures of 6 core courses, including “Eco-environment Repair Technology”, “Agro-environmental Management Plan”, “Environmental Engineering Design”, “Environmental Pest Management Technology”, “Agro-chemical Pollution Control Technology”, “Agro-environmental Testing and Analysis”. It integrates the vocational qualification certificate education and professional induction certificate training items, and enhances the adaptability, skills and professionalism of professional core curriculum.

Insights into deep-time terrestrial carbon cycle processes from modern plant isotope ecology

Science.gov (United States)

Sheldon, N. D.; Smith, S. Y.

2012-12-01

While the terrestrial biosphere and soils contain much of the readily exchangeable carbon on Earth, how those reservoirs function on long time scales and at times of higher atmospheric CO2 and higher temperatures is poorly understood, which limits our ability to make accurate future predictions of their response to anthropogenic change. Recent data compilation efforts have outlined the response of plant carbon isotope compositions to a variety of environmental factors including precipitation amount and timing, elevation, and latitude. The compilations involve numerous types of plants, typically only found at a limited number of climatic conditions. Here, we expand on those efforts by examining the isotopic response of specific plant groups found both globally and across environmental gradients including: 1) ginkgo, 2) conifers, and 3) C4 grasses. Ginkgo is presently widely distributed as a cultivated plant and the ginkgoalean fossil record spans from the Permian to the present, making it an ideal model organism to understand climatic influence on carbon cycling both in modern and ancient settings. Ginkgo leaves have been obtained from a range of precipitation conditions (400-2200 mm yr-1), including dense sampling from individuals and populations in both Mediterranean and temperate climate areas and samples of different organs and developmental stages. Ginkgo carbon isotope results plot on the global C3 plant array, are consistent among trees at single sites, among plant organs, and among development stages, making ginkgo a robust recorder of both climatic conditions and atmospheric δ13C. In contrast, a climate-carbon isotope transect in Arizona highlights that conifers (specifically, pine and juniper) record large variability between organs and have a very different δ13C slope as a function of climate than the global C3 plant array, while C4 plants have a slope with the opposite sign as a function of climate. This has a number of implications for paleo

Principles for ecologically based invasive plant management

Science.gov (United States)

Jeremy J. James; Brenda S. Smith; Edward A. Vasquez; Roger L. Sheley

2010-01-01

Land managers have long identified a critical need for a practical and effective framework for designing restoration strategies, especially where invasive plants dominate. A holistic, ecologically based, invasive plant management (EBIPM) framework that integrates ecosystem health assessment, knowledge of ecological processes, and adaptive management into a successional...

Biosemiotics and ecological monitoring

DEFF Research Database (Denmark)

Bruni, Luis Emilio

2001-01-01

of the qualitative and relational aspects that can only be grasped by considering the semiotic networks operative in complex ecological and cultural systems. In this paper, it is suggested that a biosemiotic approach to ecology may prove useful for the modelling process, which in turn will allow the construction...... of meaningful monitoring systems. It is also contended that a biosemiotic approach may also serve to better integrate our understanding and monitoring of ecosystems into the cultural process of searching for (human) sustainability....

Challenges for Social-Ecological Transformations: Contributions from Social and Political Ecology

Directory of Open Access Journals (Sweden)

Christoph Görg

2017-06-01

Full Text Available Transformation has become a major topic of sustainability research. This opens up new perspectives, but at the same time, runs the danger to convert into a new critical orthodoxy which narrows down analytical perspectives. Most research is committed towards a political-strategic approach towards transformation. This focus, however, clashes with ongoing transformation processes towards un-sustainability. The paper presents cornerstones of an integrative approach to social-ecological transformations (SET, which builds upon empirical work and conceptual considerations from Social Ecology and Political Ecology. We argue that a critical understanding of the challenges for societal transformations can be advanced by focusing on the interdependencies between societies and the natural environment. This starting point provides a more realistic understanding of the societal and biophysical constraints of sustainability transformations by emphasising the crisis-driven and contested character of the appropriation of nature and the power relations involved. Moreover, it pursues a transdisciplinary mode of research, decisive for adequately understanding any strategy for transformations towards sustainability. Such a conceptual approach of SET is supposed to better integrate the analytical, normative and political-strategic dimension of transformation research. We use the examples of global land use patterns, neo-extractivism in Latin America and the global water crisis to clarify our approach.

Isotope decay equations solved by means of a recursive method

International Nuclear Information System (INIS)

Grant, Carlos

2009-01-01

The isotope decay equations have been solved using forward finite differences taking small time steps, among other methods. This is the case of the cell code WIMS, where it is assumed that concentrations of all fissionable isotopes remain constant during the integration interval among other simplifications. Even when the problem could be solved running through a logical tree, all algorithms used for resolution of these equations used an iterative programming formulation. That happened because nearly all computer languages used up to a recent past by the scientific programmers did not support recursion, such as the case of the old versions of FORTRAN or BASIC. Nowadays also an integral form of the depletion equations is used in Monte Carlo simulation. In this paper we propose another programming solution using a recursive algorithm, running through all descendants of each isotope and adding their contributions to all isotopes in each generation. The only assumption made for this solution is that fluxes remain constant during the whole time step. Recursive process is interrupted when a stable isotope was attained or the calculated contributions are smaller than a given precision. These algorithms can be solved by means an exact analytic method that can have some problems when circular loops appear for isotopes with alpha decay, and a more general polynomial method. Both methods are shown. (author)

A framework for understanding the concerns of ecological designers

International Nuclear Information System (INIS)

DeKay, M.

1992-01-01

This paper creates a theoretical framework of analysis for understanding the concerns and methods of ecological designers. Various definitions of ecological design are reviewed to show its basis in natural ecological systems, either as analog or as context, and its purpose as creating sustainability. Ecological design methods are categorized as conceptual, factual, or integrative. The characteristics and definitions of these methods are explained and several practitioners and theorists classified. Lyle's concept of ecosystematic order is used to show the basis of methods in either a building architecture or a landscape architecture perspective. A matrix is generated and applied to a representative of each category, showing the concerns of each in terms of the integration of human and natural ecosystem structure, function, and location

A New Method to Quantify the Isotopic Signature of Leaf Transpiration: Implications for Landscape-Scale Evapotranspiration Partitioning Studies

Science.gov (United States)

Wang, L.; Good, S. P.; Caylor, K. K.

2010-12-01

Characterizing the constituent components of evapotranspiration is crucial to better understand ecosystem-level water budgets and water use dynamics. Isotope based evapotranspiration partitioning methods are promising but their utility lies in the accurate estimation of the isotopic composition of underlying transpiration and evaporation. Here we report a new method to quantify the isotopic signature of leaf transpiration under field conditions. This method utilizes a commercially available laser-based isotope analyzer and a transparent leaf chamber, modified from Licor conifer leaf chamber. The method is based on the water mass balance in ambient air and leaf transpired air. We verified the method using “artificial leaves” and glassline extracted samples. The method provides a new and direct way to estimate leaf transpiration isotopic signatures and it has wide applications in ecology, hydrology and plant physiology.

The ecological half-life of 137Cs in undisturbed silt soil

International Nuclear Information System (INIS)

Drosg, M.

2012-01-01

The time necessary to safely cultivate agricultural areas after they have been contaminated by radioactivity (e.g. after the Chernobyl accident) is not determined by the physical half-life of the radioactive isotopes in question but by their (usually much shorter) ecological half-life (). This half-life not only depends on the type of soil but also on whether the soil was fertilized or not. Therefore it is not possible to determine an ecological half-life that is universally valid. However, the value for undisturbed, unfertilized soil should provide a general indication for the duration of ecological half-life. In a silt soil in Vienna, Austria, the ecological half-life of 137 Cs was determined to be 0.8 years, which is much shorter than the physical half-life of 30 years. - Highlights: ► Absolute measurements of 137 Cs radioactivity in leaves of perennial plants. ► The natural 40 K radioactivity served as reference. ► The ecological half-life of 137 Cs in loamy soil was determined.

Inferring local ecological processes amid species pool influences

DEFF Research Database (Denmark)

Lessard, Jean-Philippe; Belmaker, Jonathan; Myers, Jonathan A.

2012-01-01

studies, null models of community structure, and ecologically explicit definitions of the species pool as a means to compare predominant ecological processes among regions. By uniting concepts and tools from community ecology and macroecology, this approach might facilitate synthesis and resolve many......Resolving contingencies in community ecology requires comparative studies of local communities along broad-scale environmental gradients and in different biogeographic regions. However, comparisons of local ecological processes among regions require a synthetic understanding of how the species pool...... of potential community members influences the structure of ecological communities. Here, we outline an integrative approach for quantifying local ecological processes while explicitly accounting for species pool influences. Specifically, we highlight the utility of combining geographically replicated local...

Integrated use of soil physical and water isotope methods for ecohydrological characterization of desertified areas

Science.gov (United States)

Külls, Christoph; Nunes, Alice; Köbel-Batista, Melanie; Branquinho, Cristina; Bianconi, Nadja; Costantini, Eduardo

2014-05-01

Measures for monitoring desertification and soil degradation require a thorough understanding of soil physical properties and of the water balance in order to guide restoration efforts (Costantini et al. 2009). It is hypothesized that long term restoration success on degraded land depends on a series of interacting factors such as exposition, soil type, soil hydrology including lateral flow on hill-slope catenae. Recently, new soil water isotope measurement techniques have been developed (Garvelmann et al. 2012) that provide much faster and reliable stable water isotope profiles in soils. This technique yield information on groundwater recharge, soil water balance and on the origin of water available for plants, which in combination with conservative chemical tracers (chloride) can be validated. A multidisciplinary study including ecologists, soil physicists and hydrologists of the COST Action Desert Restoration Hub was carried out on four semi-arid sites in Portugal. A comparative characterization of soil physical parameters, soil water isotope and chloride profiles was performed in order to estimate pedoclimate, soil aridity, soil water balance and groundwater recharge. In combination with soil physical data a comprehensive and cross-validated characterization of pedoclimate and soil aridity was obtained. These indicators were then integrated and related to plant cover. The long-term rainfall of the four sites ranges from 512 to 638 mm, whereas air temperature is from 15.8 to 17.0°C. The De Martonne index of aridity spans from 19.3 to 24.6, pointing to semiarid to moderately arid climatic conditions. The long-term average number of days when the first 0.50 m of soil is dry ranges from 110 to 134, while the mean annual soil temperature at 0.50 m spans from 15.8 and 19.1°C. The studied profiles show different hydrological characteristics, in particular, the estimated hydraulic conductivity ranges from 0.1-1 to 10-100 µm/s. Three out of four profiles show a

In search of an adaptive social-ecological approach to understanding a tropical city

Science.gov (United States)

A.E. Lugo; C.M. Concepcion; L.E. Santiago-Acevedo; T.A. Munoz-Erickson; J.C. Verdejo Ortiz; R. Santiago-Bartolomei; J. Forero-Montana; C.J. Nytch; H. Manrique; W. Colon-Cortes

2012-01-01

This essay describes our effort to develop a practical approach to the integration of the social and ecological sciences in the context of a Latin-American city such as San Juan, Puerto Rico. We describe our adaptive social-ecological approach in the historical context of the developing paradigms of the Anthropocene, new integrative social and ecological sciences, and...

What is dental ecology?

Science.gov (United States)

Cuozzo, Frank P; Sauther, Michelle L

2012-06-01

Teeth have long been used as indicators of primate ecology. Early work focused on the links between dental morphology, diet, and behavior, with more recent years emphasizing dental wear, microstructure, development, and biogeochemistry, to understand primate ecology. Our study of Lemur catta at the Beza Mahafaly Special Reserve, Madagascar, has revealed an unusual pattern of severe tooth wear and frequent tooth loss, primarily the result of consuming a fallback food for which these primates are not dentally adapted. Interpreting these data was only possible by combining our areas of expertise (dental anatomy [FC] and primate ecology [MS]). By integrating theoretical, methodological, and applied aspects of both areas of research, we adopted the term "dental ecology"-defined as the broad study of how teeth respond to the environment. Specifically, we view dental ecology as an interpretive framework using teeth as a vehicle for understanding an organism's ecology, which builds upon earlier work, but creates a new synthesis of anatomy and ecology that is only possible with detailed knowledge of living primates. This framework includes (1) identifying patterns of dental pathology and tooth use-wear, within the context of feeding ecology, behavior, habitat variation, and anthropogenic change, (2) assessing ways in which dental development and biogeochemical signals can reflect habitat, environmental change and/or stress, and (3) how dental microstructure and macro-morphology are adapted to, and reflect feeding ecology. Here we define dental ecology, provide a short summary of the development of this perspective, and place our new work into this context. Copyright © 2012 Wiley Periodicals, Inc.

Effects of euthanasia method on stable-carbon and stable-nitrogen isotope analysis for an ectothermic vertebrate.

Science.gov (United States)

Atwood, Meredith A

2013-04-30

Stable isotope analysis is a critical tool for understanding ecological food webs; however, results can be sensitive to sample preparation methods. To limit the possibility of sample contamination, freezing is commonly used to euthanize invertebrates and preserve non-lethal samples from vertebrates. For destructive sampling of vertebrates, more humane euthanasia methods are preferred to freezing and it is essential to evaluate how these euthanasia methods affect stable isotope results. Stable isotope ratios and elemental composition of carbon and nitrogen were used to evaluate whether the euthanasia method compromised the integrity of the sample for analysis. Specifically, the stable isotope and C:N ratios were compared for larval wood frogs (Rana sylvatica  =  Lithobates sylvaticus), an ectothermic vertebrate, that had been euthanized by freezing with four different humane euthanasia methods: CO2, benzocaine, MS-222 (tricaine methanesulfonate), and 70% ethanol. The euthanasia method was not related to the δ(13)C or δ(15)N values and the comparisons revealed no differences between freezing and any of the other treatments. However, there were slight (non-significant) differences in the isotope ratios of benzocaine and CO2 when each was compared with freezing. The elemental composition was altered by the euthanasia method employed. The percentage nitrogen was higher in CO2 treatments than in freezing, and similar (non-significant) trends were seen for ethanol treatments relative to freezing. The resulting C:N ratios were higher for benzocaine treatments than for both CO2 and ethanol. Similar (non-significant) trends suggested that the C:N ratios were also higher for animals euthanized by freezing than for both CO2 and ethanol euthanasia methods. The euthanasia method had a larger effect on elemental composition than stable isotope ratios. The percentage nitrogen and the subsequent C:N ratios were most affected by the CO2 and ethanol euthanasia methods, whereas

Effectiveness of birds, butterflies, dragonflies, damselflies and invertebrates as indicators of freshwater ecological integrity

Science.gov (United States)

Chama, Lackson; Siachoono, Stanford

2015-04-01

Human activities such as mining and agriculture are among the major threats to biodiversity globally. Discharges from these activities have been shown to negatively affect ecological processes, leading to ecosystem degradation and species loss across biomes. Freshwater systems have been shown to be particularly vulnerable, as discharges tend to spread rapidly here than in other ecosystems. Hence, there is need to routinely monitor the quality of these systems if impacts of discharges from human activities are to be minimised. Besides the use of conventional laboratory techniques, several studies have recently shown that organisms such as birds, butterflies, dragonflies, damselflies and invertebrates are also good indicators of ecological integrity and should therefore be used as alternatives to monitoring the quality of various ecosystems. However, most of these studies have only studied one or two of these organisms against ecosystem health, and it remains unclear whether all of them respond similarly to changes in different drivers of environmental change. We investigated the response of the diversity of birds, butterflies, dragonflies, damselflies and invertebrates to changing water quality along the Kafue River in Zambia. Sampling was done at 13 different sampling points stretching over a distance of 60Km along the river. At each point, both the diversity of each organism and the water quality were assessed. Water quality was determined by testing its temperature, pH, redox, electrical conductivity, turbidity and copper parameters. We then tested how the diversity of each organism responded to changes in these water parameters. All water parameters varied significantly across sampling points. The diversity of birds and damselflies remained unaffected by any of the water parameters used. However, the diversity of butterflies reduced with increasing pH, turbidity and copper, albeit it remained unaffected by other water parameters. The diversity of dragonflies

Integrated Assessment Of Groundwater Recharge In The North Kelantan River Basin Using Environmental Water Stable Isotopes, Tritium And Chloride Data

International Nuclear Information System (INIS)

Wan Zakaria Wan Muhamad Tahir; Nur Hayati Hussin; Ismail Yusof; Kamaruzaman Mamat; Johari Abdul Latif; Rohaimah Demanah

2014-01-01

Estimation and understanding of groundwater recharge mechanism and capacity of aquifer are essential issues in water resources investigation. An integrated study of environmental chloride content in the unsaturated zone using chloride mass balance method (CMB) and isotopic analyses of deuterium, oxygen-18, and tritium values range in the alluvial channel aquifer profiles (quaternary sediments) of the North Kelantan River basin has been carried out in order to estimate and understand groundwater recharge processes. However, the rate of aquifer recharge is one of the most difficult factors to measure in the evaluation of ground water resources. Estimation of recharge, by whatever method, is normally subject to large uncertainties and errors. In this paper, changes in stable isotopic signatures in different seasons and tritium analysis of the sampled groundwater observed at different depth in the aquifer system were evaluated. Stable isotope data are slightly below the local meteoric water line (LMWL) indicating that there is some isotopic enrichment due to direct evaporation through the soil surface which is exposed prior or during the recharging process. The overall data on water isotopic signatures from boreholes and production wells (shallow and relatively deep aquifer system) are spread over a fairly small range but somewhat distinct compared to river water isotopic compositions. Such a narrow variation in isotopic signatures of the sampled groundwaters may suggest that all groundwater samples originated from the same area of direct recharge predominantly from rainfall and nearby rivers. Environmental tritium data measured in groundwater at different depths and locations together with a medium-term of limited monthly rainfall collections were used to investigate the groundwater age distributions (residence times). The existence of groundwater in the aquifer system (sampled wells) is predominantly designated as modern (young) water that has undergone recharged

Quantifying mercury isotope dynamics in captive Pacific bluefin tuna (Thunnus orientalis

Directory of Open Access Journals (Sweden)

Sae Yun Kwon

2016-02-01

Full Text Available Abstract Analyses of mercury (Hg isotope ratios in fish tissues are used increasingly to infer sources and biogeochemical processes of Hg in natural aquatic ecosystems. Controlled experiments that can couple internal Hg isotope behavior with traditional isotope tracers (δ13C, δ15N can improve the applicability of Hg isotopes as natural ecological tracers. In this study, we investigated changes in Hg isotope ratios (δ202Hg, Δ199Hg during bioaccumulation of natural diets in the pelagic Pacific bluefin tuna (Thunnus orientalis; PBFT. Juvenile PBFT were fed a mixture of natural prey and a dietary supplement (60% Loligo opalescens, 31% Sardinops sagax, 9% gel supplement in captivity for 2914 days, and white muscle tissues were analyzed for Hg isotope ratios and compared to time in captivity and internal turnover of δ13C and δ15N. PBFT muscle tissues equilibrated to Hg isotope ratios of the dietary mixture within ∼700 days, after which we observed a cessation in further shifts in Δ199Hg, and small but significant negative δ202Hg shifts from the dietary mixture. The internal behavior of Δ199Hg is consistent with previous fish studies, which showed an absence of Δ199Hg fractionation during Hg bioaccumulation. The negative δ202Hg shifts can be attributed to either preferential excretion of Hg with higher δ202Hg values or individual variability in captive PBFT feeding preferences and/or consumption rates. The overall internal behavior of Hg isotopes is similar to that described for δ13C and δ15N, though observed Hg turnover was slower compared to carbon and nitrogen. This improved understanding of internal dynamics of Hg isotopes in relation to δ13C and δ15N enhances the applicability of Hg isotope ratios in fish tissues for tracing Hg sources in natural ecosystems.

Isotopes of water. A biblography

International Nuclear Information System (INIS)

Summers, W.K.; Sittler, C.J.

1976-01-01

This bibliography contains at least 2300 references to currently available literature on the isotopes of water-viz., hydrogen, deuterium, tritium, and 16 O and 18 O forms. The bulk of the references appeared before 1975. The references are presented in two parts. Part I contains those references relating to tritium. The references in this part are included under the following categories: bibliography; symposia, conferences and collections; methods for measurement; decay rate; tritium production; meteorites and moon rocks; history and state of the art; processing and handling; proposals for using; methods in hydrologic studies; hydrologic cycle; biology and ecology; nuclear facilities; and supportive techniques. References to deuterium and oxygen are included in Part II. These references are organized under the following headings: bibliography; symposia, conferences and collections; history and state of the art; proposals for using; methods for measurement; physics, chemistry and thermodynamics; water, water vapor and ice; carbon dioxide and carbon dioxide-water; biology and ecology; extraterrestrial studies; concentrations in rocks and minerals; hydrologic cycle; hydrocarbons; paleotemperatures and paleoclimatology

Advective isotope transport by mixing cell and particle tracking algorithms

International Nuclear Information System (INIS)

Tezcan, L.; Meric, T.

1999-01-01

The 'mixing cell' algorithm of the environmental isotope data evaluation is integrated with the three dimensional finite difference ground water flow model (MODFLOW) to simulate the advective isotope transport and the approach is compared with the 'particle tracking' algorithm of the MOC3D, that simulates three-dimensional solute transport with the method of characteristics technique

Integrated modelling of enhanced in situ biodenitrification in a fractured aquifer: biogeochemistry and isotope geochemistry

Science.gov (United States)

Rodríguez-Escales, Paula; Folch, Albert; van Breukelen, Boris M.; Vidal-Gavilan, Georgina; Soler, Albert

2014-05-01

Enhanced in-situ biodenitrification is a feasible technology to recovery groundwater polluted by nitrates and achieves drinking water standards. Under optimum conditions, nitrate is reduced by autochthonous bacteria trough different reactions until arrive to harmless dinitrogen gas. Isotopic fractionation monitoring in field applications allows knowing the exact degree and the real scope of this technology. Using the Rayleigh equation the change in the isotope ratio of the nitrate molecule (δ15N-NO3-, δ18O-NO3-) is related to the fraction of molecules remaining as a result of biodenitrification. However, Rayleigh application at field scale is sometimes limited due to other processes involved during groundwater flow such as dispersion or adsorption and geological media heterogeneities that interferes in concentration values. Then, include isotope fractionation processes in reactive transport models is a useful tool to interpret and predict data from in-situ biodenitrification. We developed a reactive transport model of enhanced in situ application at field scale in a fractured aquifer that considers biogeochemical processes as well as isotope fractionation to enable better monitoring and management of this technology. Processes considered were: microbiological- exogenous and endogenous nitrate and sulfate respiration coupled with microbial growth and decay, geochemical reactions (precipitation of calcite) and isotopic fractionation (δ15N-NO3-; δ18O- NO3- and carbon isotope network). The 2-D simulations at field scale were developed using PHAST code. Modeling of nitrate isotope geochemistry has allowed determining the extent of biodenitrification in model domain. We have quantified which is the importance in decreasing of nitrate concentrations due to biodegradation (percentage of biodegradation, 'B%') and due to dilution process (percentage of dilution, 'D%'). On the other hand, the stable carbon isotope geochemistry has been modeled. We have considered the

Predicting phenology by integrating ecology, evolution and climate science

Science.gov (United States)

Pau, Stephanie; Wolkovich, Elizabeth M.; Cook, Benjamin I.; Davies, T. Jonathan; Kraft, Nathan J.B.; Bolmgren, Kjell; Betancourt, Julio L.; Cleland, Elsa E.

2011-01-01

Forecasting how species and ecosystems will respond to climate change has been a major aim of ecology in recent years. Much of this research has focused on phenology — the timing of life-history events. Phenology has well-demonstrated links to climate, from genetic to landscape scales; yet our ability to explain and predict variation in phenology across species, habitats and time remains poor. Here, we outline how merging approaches from ecology, climate science and evolutionary biology can advance research on phenological responses to climate variability. Using insight into seasonal and interannual climate variability combined with niche theory and community phylogenetics, we develop a predictive approach for species' reponses to changing climate. Our approach predicts that species occupying higher latitudes or the early growing season should be most sensitive to climate and have the most phylogenetically conserved phenologies. We further predict that temperate species will respond to climate change by shifting in time, while tropical species will respond by shifting space, or by evolving. Although we focus here on plant phenology, our approach is broadly applicable to ecological research of plant responses to climate variability.

Civic Ecology: A Postmodern Approach to Ecological Sustainability

Science.gov (United States)

Lopes, V. L.

2013-12-01

Human agency is transforming the planetary processes at unprecedented rates risking damaging essential life-support systems. Climate change, massive species extinction, land degradation, resources depletion, overpopulation, poverty and social injustice are all the result of human choices and non-sustainable ways of life. The survival of our modern economic systems depends upon insatiable consumption - a simple way of life no longer satisfies most people. Detached, instrumental rationality has created an ideal of liberalism based on individual pursuit of self-interest, leading the way into unprecedented material progress but bringing with it human alienation, social injustice, and ecological degradation. The purpose of this presentation is to introduce a community-based systems response to a growing sense that the interlocked social-ecological crisis is as much a problem of human thought and behavior as it is about identifying carrying capacities and CO2 concentrations in the atmosphere. This approach, referred to here as civic ecology, presents a new and important paradigm shift in sustainability practice that attempts to bring together and integrate ecological ideas and postmodern thinking. As such, it is as much a holistic, dynamic, and synergistic approach to ecological sustainability, as it is a philosophy of life and ethical perspective born of ecological understanding and insight. Civic ecology starts with the proposition that the key factor determining the health of the ecosphere is the behavior of human beings, and therefore many of the most important issues related to sustainability lie in the areas of human thought and culture. Thus, the quest for sustainability must include as a central concern the transformation of psychological and behavioral patterns that have become an imminent danger to planetary health. At the core of this understanding is a fundamental paradigm shift from the basic commitments of modern Western culture to its model of mechanism

Landscape ecological assessment: a tool for integrating biodiversity issues in strategic environmental assessment and planning.

Science.gov (United States)

Mörtberg, U M; Balfors, B; Knol, W C

2007-03-01

To achieve a sustainable development, impacts on biodiversity of urbanisation, new infrastructure projects and other land use changes must be considered on landscape and regional scales. This requires that important decisions are made after a systematic evaluation of environmental impacts. Landscape ecology can provide a conceptual framework for the assessment of consequences of long-term development processes like urbanisation on biodiversity components, and for evaluating and visualising the impacts of alternative planning scenarios. The aim of this paper was to develop methods for integrating biodiversity issues in planning and strategic environmental assessment in an urbanising environment, on landscape and regional levels. In order to test developed methods, a case study was conducted in the region of Stockholm, the capital of Sweden, and the study area embraced the city centre, suburbs and peri-urban areas. Focal species were tested as indicators of habitat quality, quantity and connectivity in the landscape. Predictive modelling of habitat distribution in geographic information systems involved the modelling of focal species occurrences based on empirical data, incorporated in a landscape ecological decision support system. When habitat models were retrieved, they were applied on future planning scenarios in order to predict and assess the impacts on focal species. The scenario involving a diffuse exploitation pattern had the greatest negative impacts on the habitat networks of focal species. The scenarios with concentrated exploitation also had negative impacts, although they were possible to mitigate quite easily. The predictions of the impacts on habitats networks of focal species made it possible to quantify, integrate and visualise the effects of urbanisation scenarios on aspects of biodiversity on a landscape level.

The Integration of Social-Ecological Resilience and Law

Science.gov (United States)

Growing recognition of the inherent uncertainty associated with the dynamics of ecological systems and their often non-linear and surprising behavior, however, presents a set of problems outside the scope of classic environmental law, and has lead to a fundamental understanding a...

International symposium on isotope hydrology and integrated water resources management. Unedited proceedings

International Nuclear Information System (INIS)

2004-01-01

Global effects to overcome the growing challenge of freshwater availability have been at the forefront of the world development agenda for nearly three decades. For developing policies towards sustainable management of freshwater resources, an improved understanding of the Earth's water cycle bas been widely recognized as one of the key elements of scientific information. The IAEA has played a crucial role in promoting and expanding the field of isotope hydrology. Starting in 1963, the IAEA's quadrennial symposia on isotope hydrology have played a central role in developing this scientific discipline. This publication contains 174 extended abstracts of papers and posters presented during 11 technical sessions of the 11th symposium in the series that was convened during 19-23 May 2003 in Vienna. Nearly 275 participants from 69 countries participated in the symposium to discuss the past, present and future of isotope applications in hydrology and climate research. Each of the papers and poster presentations have been analysed and indexed separately

Integrated pest management

International Nuclear Information System (INIS)

LaBrecque, G.C.

1981-01-01

An effective Integrated Pest Management (IPM) programme requires a thorough knowledge of the biology of the target species, namely information on the dispersal, population densities and dynamics as well as the ecology of the natural enemies of the pest. Studies on these can be accomplished by radiolabelling techniques. In the event that conditions prevent the use of radioisotopes the insects can be labelled with either a rare earth or stable isotopes. All insects treated with the rare earths, once captured, are exposed to neutrons which produce radioactivity in the rare earths. There are two other approaches in the practical application of radiation to the problem of insect control: the exposure of insects to lethal doses of radiation and the release of sterile insects. The Insect and Pest Control Section contributes to all aspects of the sterile insect technique (SIT) and it is involved in the Agency's Coordinated Research Programme which permits scientists from the developing countries to meet to discuss agricultural problems and to devise means of solving crop-pest infestation problems by using isotopes and radiation. The success of radiation in insect pest control was underlined and reviewed at the international symposium on the sterile insect technique and the use of radiation in genetic insect control jointly organized by the FAO and the IAEA and held in the FRG in 1981. Another important action is the BICOT programme in Nigeria between the IAEA and the Government of Nigeria on the biological control of tsetse flies by SIT

Manual on mathematical models in isotope hydrogeology

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-10-01

Methodologies based on the use of naturally occurring isotopes are, at present, an integral part of studies being undertaken for water resources assessment and management. Quantitative evaluations based on the temporal and/or spatial distribution of different isotopic species in hydrological systems require conceptual mathematical formulations. Different types of model can be employed depending on the nature of the hydrological system under investigation, the amount and type of data available, and the required accuracy of the parameter to be estimated. This manual provides an overview of the basic concepts of existing modelling approaches, procedures for their application to different hydrological systems, their limitations and data requirements. Guidance in their practical applications, illustrative case studies and information on existing PC software are also included. While the subject matter of isotope transport modelling and improved quantitative evaluations through natural isotopes in water sciences is still at the development stage, this manual summarizes the methodologies available at present, to assist the practitioner in the proper use within the framework of ongoing isotope hydrological field studies. In view of the widespread use of isotope methods in groundwater hydrology, the methodologies covered in the manual are directed towards hydrogeological applications, although most of the conceptual formulations presented would generally be valid. Refs, figs, tabs.

Manual on mathematical models in isotope hydrogeology

International Nuclear Information System (INIS)

1996-10-01

Methodologies based on the use of naturally occurring isotopes are, at present, an integral part of studies being undertaken for water resources assessment and management. Quantitative evaluations based on the temporal and/or spatial distribution of different isotopic species in hydrological systems require conceptual mathematical formulations. Different types of model can be employed depending on the nature of the hydrological system under investigation, the amount and type of data available, and the required accuracy of the parameter to be estimated. This manual provides an overview of the basic concepts of existing modelling approaches, procedures for their application to different hydrological systems, their limitations and data requirements. Guidance in their practical applications, illustrative case studies and information on existing PC software are also included. While the subject matter of isotope transport modelling and improved quantitative evaluations through natural isotopes in water sciences is still at the development stage, this manual summarizes the methodologies available at present, to assist the practitioner in the proper use within the framework of ongoing isotope hydrological field studies. In view of the widespread use of isotope methods in groundwater hydrology, the methodologies covered in the manual are directed towards hydrogeological applications, although most of the conceptual formulations presented would generally be valid. Refs, figs, tabs

Defining fish community structure in Lake Winnipeg using stable isotopes (δ{sup 13}C, δ{sup 15}N, δ{sup 34}S): Implications for monitoring ecological responses and trophodynamics of mercury and other trace elements

Energy Technology Data Exchange (ETDEWEB)

Ofukany, Amy F.A. [Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, Saskatchewan S7N 5B3 (Canada); Wassenaar, Leonard I. [Environment Canada, 11 Innovation Boulevard, Saskatoon, Saskatchewan S7N 3H5 (Canada); Bond, Alexander L., E-mail: alex.bond@rspb.org.uk [Environment Canada, 11 Innovation Boulevard, Saskatoon, Saskatchewan S7N 3H5 (Canada); Hobson, Keith A. [Environment Canada, 11 Innovation Boulevard, Saskatoon, Saskatchewan S7N 3H5 (Canada)

2014-11-01

The ecological integrity of freshwater lakes is influenced by atmospheric and riverine deposition of contaminants, shoreline development, eutrophication, and the introduction of non-native species. Changes to the trophic structure of Lake Winnipeg, Canada, and consequently, the concentrations of contaminants and trace elements measured in tissues of native fishes, are likely attributed to agricultural runoff from the 977,800 km{sup 2} watershed and the arrival of non-native zooplankters and fishes. We measured δ{sup 13}C, δ{sup 15}N, and δ{sup 34}S along with concentrations of 15 trace elements in 17 native fishes from the north and south basins of Lake Winnipeg in 2009 and 2010. After adjusting for differences in isotopic baseline values between the two basins, fishes in the south basin had consistently higher δ{sup 13}C and δ{sup 34}S, and lower δ{sup 15}N. We found little evidence of biomagnification of trace elements at the community level, but walleye (Sander vitreus) and freshwater drum (Aplodinotus grunniens) had higher mercury and selenium concentrations with increased trophic position, coincident with increased piscivory. There was evidence of growth dilution of cobalt, copper, manganese, molybdenum, thallium, and vanadium, and bioaccumulation of mercury, which could be explained by increases in algal (and consequently, lake and fish) productivity. We conclude that the north and south basins of Lake Winnipeg represent very different communities with different trophic structures and trace element concentrations. - Highlights: • Anthropogenic eutrophication and non-native species affect Lake Winnipeg’s ecosystem. • We measured stable isotopes and trace elements in 15 native fish species. • There was more evidence for growth dilution than biomagnification for most elements. • The trophic structures of the north and south basins were different. • These results will help determine the effects of recent arrival of zebra mussels.

Ecoinformatics: supporting ecology as a data-intensive science

OpenAIRE

Michener, William H.; Jones, Matthew B.

2012-01-01

Ecology is evolving rapidly and increasingly changing into a more open, accountable, interdisciplinary, collaborative and data-intensive science. Discovering, integrating and analyzing massive amounts of heterogeneous data are central to ecology as researchers address complex ques- tions at scales from the gene to the biosphere. Ecoinfor- matics offers tools and approaches for managing ecological data and transforming the data into informa- tion and knowledge. Here, we review the state-of-the...

Partial valuation of the goods and services that it provides the mangrove ecosystem: An integrated ecological-economic analysis

International Nuclear Information System (INIS)

Castiblanco R, Carmenza

2002-01-01

The article presents a methodology to value the economic benefits of the use of some goods and services that provides the mangrove ecosystem, located in the municipality of Tumaco. An ecological analysis is developed integrated to an economic evaluation that allows expressing in monetary terms some values of use of the mangrove; this value are compared with the profitability that reports the Camaroniculture, productive activity that is constituted at the moment, in the most profitable alternative use

Ecological and Economic Problems of Environmental Security

Directory of Open Access Journals (Sweden)

Mashchenko Maryna A.

2018-03-01

Full Text Available The article is aimed at defining a common mechanism for assessing the ecological and economic threats and ecological losses on the basis of a long-term study to ensure the environmental security of the State. The necessity of a new approach to the State regulation through achievement of environmental security is displayed, that will allow to reduce tensions of the ecological-economic problems in Ukraine. For implementation of this approach, a general mechanism for estimation of ecological-economic threats and ecological losses is provided, which is carried out through formation of an integral costs system. The costs system is presented in the article in the form of an in-depth mechanism for estimating the ecological-economic threats on the example of ecological impacts. Structuring and preparation of the costs system for applied researches is the next stage of this prolonged research.

A measuring system for the fast simultaneous isotope ratio and elemental analysis of carbon, hydrogen, nitrogen and sulfur in food commodities and other biological material.

Science.gov (United States)

Sieper, Hans-Peter; Kupka, Hans-Joachim; Williams, Tony; Rossmann, Andreas; Rummel, Susanne; Tanz, Nicole; Schmidt, Hanns-Ludwig

2006-01-01

The isotope ratio of each of the light elements preserves individual information on the origin and history of organic natural compounds. Therefore, a multi-element isotope ratio analysis is the most efficient means for the origin and authenticity assignment of food, and also for the solution of various problems in ecology, archaeology and criminology. Due to the extraordinary relative abundances of the elements hydrogen, carbon, nitrogen and sulfur in some biological material and to the need for individual sample preparations for H and S, their isotope ratio determination currently requires at least three independent procedures and approximately 1 h of work. We present here a system for the integrated elemental and isotope ratio analysis of all four elements in one sample within 20 min. The system consists of an elemental analyser coupled to an isotope ratio mass spectrometer with an inlet system for four reference gases (N(2), CO(2), H(2) and SO(2)). The combustion gases are separated by reversible adsorption and determined by a thermoconductivity detector; H(2)O is reduced to H(2). The analyser is able to combust samples with up to 100 mg of organic material, sufficient to analyse samples with even unusual elemental ratios, in one run. A comparison of the isotope ratios of samples of water, fruit juices, cheese and ethanol from wine, analysed by the four-element analyser and by classical methods and systems, respectively, yielded excellent agreements. The sensitivity of the device for the isotope ratio measurement of C and N corresponds to that of other systems. It is less by a factor of four for H and by a factor of two for S, and the error ranges are identical to those of other systems. Copyright (c) 2006 John Wiley & Sons, Ltd.

Stable isotopes provide new insights into vestimentiferan physiological ecology at Gulf of Mexico cold seeps

Science.gov (United States)

Becker, Erin Leigh; Macko, Stephen A.; Lee, Raymond W.; Fisher, Charles R.

2011-02-01

On the otherwise low-biomass seafloor of the Gulf of Mexico (GoM) continental slope, natural oil and gas seeps are oases of local primary production that support lush animal communities. Hundreds of seep communities have been documented on the continental slope, and nutrition derived from seeps could be an important link in the overall GoM food web. Here, we present a uniquely large and cohesive data set of δ13C, δ15N, and δ34S compositions of the vestimentiferan tubeworms Escarpia laminata and Lamellibrachia sp. 1, which dominate biomass at GoM seeps and provide habitat for hundreds of other species. Our sampling design encompassed an entire region of the GoM lower slope, allowing us for the first time to assess spatial variability in isotope compositions and to robustly address long-standing hypotheses about how vestimentiferans acquire and cycle nutrients over their long lifespan (200+ years). Tissue δ13C values provided strong evidence that larger adult vestimentiferans use their buried roots to take up dissolved inorganic carbon from sediment pore water, while very small individuals use their plume to take up carbon dioxide from the seawater. δ34S values were extremely variable among individuals of the same species within one location (<1 m2 area), indicating high variability in the inorganic sulfur pools on a very small spatial scale. This finding supports the hypothesis that vestimentiferans use their roots to cycle sulfate and sulfide between their symbionts and free-living consortia of sulfate-reducing archaea in the sediment. Finally, consistent differences in δ15N between two cooccurring vestimentiferan species provided the first strong evidence for partitioning of inorganic resources, which has significant implications for the ecology and evolution of this taxonomic group.

Stable isotopes confirm a coastal diet for critically endangered Mediterranean monk seals.

Science.gov (United States)

Karamanlidis, Alexandros A; Curtis, P Jeff; Hirons, Amy C; Psaradellis, Marianna; Dendrinos, Panagiotis; Hopkins, John B

2014-01-01

Understanding the ecology and behaviour of endangered species is essential for developing effective management and conservation strategies. We used stable isotope analysis to investigate the foraging behaviour of critically endangered Mediterranean monk seals (Monachus monachus) in Greece. We measured carbon and nitrogen isotope ratios (expressed as δ(13)C and δ(15)N values, respectively) derived from the hair of deceased adult and juvenile seals and the muscle of their known prey to quantify their diets. We tested the hypothesis that monk seals primarily foraged for prey that occupy coastal habitats in Greece. We compared isotope values from seal hair to their coastal and pelagic prey (after correcting all prey for isotopic discrimination) and used these isotopic data and a stable isotope mixing model to estimate the proportion of coastal and pelagic resources consumed by seals. As predicted, we found that seals had similar δ(13)C values as many coastal prey species and higher δ(13)C values than pelagic species; these results, in conjunction with mean dietary estimates (coastal=61 % vs. pelagic=39 %), suggest that seals have a diverse diet comprising prey from multiple trophic levels that primarily occupy the coast. Marine resource managers should consider using the results from this study to inform the future management of coastal habitats in Greece to protect Mediterranean monk seals.

Determination of the hydrogen isotopic compositions of organic materials and hydrous minerals using thermal combustion laser spectroscopy.

Science.gov (United States)

Koehler, Geoff; Wassenaar, Leonard I

2012-04-17

Hydrogen isotopic compositions of hydrous minerals and organic materials were measured by combustion to water, followed by optical isotopic analysis of the water vapor by off-axis integrated cavity output spectroscopy. Hydrogen and oxygen isotopic compositions were calculated by numerical integration of the individual isotopologue concentrations measured by the optical spectrometer. Rapid oxygen isotope exchange occurs within the combustion reactor between water vapor and molecular oxygen so that only hydrogen isotope compositions may be determined. Over a wide range in sample sizes, precisions were ±3-4 per mil. This is comparable but worse than continuous flow-isotope ratio mass spectroscopy (CF-IRMS) methods owing to memory effects inherent in water vapor transfer. Nevertheless, the simplicity and reduced cost of this analysis compared to classical IRMS or CF-IRMS methods make this an attractive option to determine the hydrogen isotopic composition of organic materials where the utmost precision or small sample sizes are not needed.

The A.B.Cs of isotope hydrology

International Nuclear Information System (INIS)

Maduabuchi, C.

2000-01-01

The steady growth in world population coupled with the extension of irrigated agriculture and accelerated industrial development and other economic activities have put tremendous stress on the quantity and quality aspects of surface and groundwater resources the world over. The situation calls for necessary monitoring mechanism to safeguard these renewable but potentially depletable resources. A proper understanding of water resources systems is a prerequisite to their sustainable development. This informed the application of isotope techniques in hydrology as they provide vital information that are not readily obtainable from the classical hydrological techniques. These include issues relating to origin and history of groundwater, recharge estimates, vulnerability of aquifers to pollution, mixing proportion of component flows and study of geothermal systems amongst others. Maximum benefits are derived from the application of isotope techniques when they are complemented with conventional techniques in an integrated manner. The paper discusses the basic concepts which include configuration of the nucleus of the atom, isotopes, radioactivity and radioactive decay law. It further explains the occurrence of environmental isotopes including their measurement in natural compounds and the general application of isotopes in water resources development and management

Can Law Foster Social-Ecological Resilience?

Directory of Open Access Journals (Sweden)

Ahjond S. Garmestani

2013-06-01

Full Text Available Law plays an essential role in shaping natural resource and environmental policy, but unfortunately, many environmental laws were developed around the prevailing scientific understanding that there was a "balance of nature" that could be managed and sustained. This view assumes that natural resource managers have the capacity to predict the behavior of ecological systems, know what its important functional components are, and successfully predict the outcome of management interventions. This paper takes on this problem by summarizing and synthesizing the contributions to this Special Feature (Law and Social-Ecological Resilience, Part I: Contributions from Resilience 2011, focusing on the interaction of law and social-ecological resilience, and then offering recommendations for the integration of law and social-ecological resilience.

What can Fe stable isotopes tell us about magmas?

DEFF Research Database (Denmark)

Stausberg, Niklas

the differentiation of magmas from the perspective of Fe stable isotopes, integrated with petrology, by studying igneous rocks and their constituent phases (minerals and glasses) from the Bushveld Complex, South Africa, Thingmuli, Iceland, Pantelleria, Italy, and the Bishop Tuff, USA. The findings are interpreted......The majority of the Earth’s crust is formed by magmas, and understanding their production and differentiation is important to interpret the geologic rock record. A powerful tool to investigate magmatic processes is the distribution of the stable isotopes of the major redox-sensitive element...... in magmas, Fe. Fe isotope compositions of magmatic rocks exhibit systematic differences, where the heaviest compositions are found in rhyolites and granites. Understanding of these systematics is complicated by a lack of constraints on Fe isotope fractionation among minerals and liquids under magmatic...

Toward Gleasonian landscape ecology: From communities to species, from patches to pixels

Science.gov (United States)

Samuel A. Cushman; Jeffrey S. Evans; Kevin McGarigal; Joseph M. Kiesecker

2010-01-01

The fusion of individualistic community ecology with the Hutchinsonian niche concept enabled a broad integration of ecological theory, spanning all the way from the niche characteristics of individual species, to the composition, structure, and dynamics of ecological communities. Landscape ecology has been variously described as the study of the structure, function,...

Guide for developing conceptual models for ecological risk assessments

International Nuclear Information System (INIS)

Suter, G.W., II.

1996-05-01

Ecological conceptual models are the result of the problem formulation phase of an ecological risk assessment, which is an important component of the Remedial Investigation process. They present hypotheses of how the site contaminants might affect the site ecology. The contaminant sources, routes, media, routes, and endpoint receptors are presented in the form of a flow chart. This guide is for preparing the conceptual models; use of this guide will standardize the models so that they will be of high quality, useful to the assessment process, and sufficiently consistent so that connections between sources of exposure and receptors can be extended across operable units (OU). Generic conceptual models are presented for source, aquatic integrator, groundwater integrator, and terrestrial OUs

Attempts for an integrative (ecological) assessment of groundwater ecosystems status

Science.gov (United States)

Griebler, Christian; Kellermann, Claudia; Jürgen Hahn, Hans; Stein, Heide; Brielmann, Heike; Berkhoff, Sven; Fuchs, Andreas

2014-05-01

Today the assessment of the ecological status of surface waters is routine and made its way into national and international (e.g. European Water Framework Directive) regulations. For groundwater and aquifers a comparable approach, considering ecological aspects, is still missing. In contrast, groundwater monitoring and management schemes follow exclusively physical-chemical and quantitative criteria. However, groundwater systems are, although persistently neglected, ecosystems harboring diverse communities of microorganisms and invertebrates. Directly linked to the biological components, groundwater systems provide various ecosystem services of societal relevance (natural production of clean drinking water). In the recent past, we developed a first concept of an ecologically sound assessment scheme for groundwater systems. Work included (1) the selection of appropriate biological/ecological criteria, (2) set-up of a groundwater ecosystem typology, (3) deduction of natural biological groundwater background values and definition of reference conditions for selected sites, and (4) a first evaluation model. Groundwater has been analyzed repeatedly of more than 100 wells distributed over five investigation areas spread all over Germany. The investigated sites could be assigned to different natural regions, geological regions, hydrogeological units, and aquifer types. The mismatch of groundwater faunal communities with the established classification schemes led to the proposal of 'stygoregions' for Germany. The presentation introduces a number of microbial and faunistic assessment criteria, which have been tested and natural background values which have been deduced. Finally, a tiered framework for assessing groundwater ecosystem status which allows an easy and fast evaluation is introduced.

Site-Specific ecological risk assessment. Case-study 2

DEFF Research Database (Denmark)

Jensen, John

“Development of a decision support system for sustainable management of contaminated land by linking bioavailability, ecological risk and ground water pollution of organic pollutants”or in short “LIBERATION”. The presentation includes examples on how to scale and integrate the results from various scientific......The decision supporting and integrating assessment tool, TRIAD, is used site-specific on PAH- and heavy metal contaminated sites in Denmark. The various aspects of the TRIAD approach are used on a set of chemistry-, ecotoxicology- and ecology related data collected among others in the EU project...

Temporal ecology in the Anthropocene.

Science.gov (United States)

Wolkovich, E M; Cook, B I; McLauchlan, K K; Davies, T J

2014-11-01

Two fundamental axes - space and time - shape ecological systems. Over the last 30 years spatial ecology has developed as an integrative, multidisciplinary science that has improved our understanding of the ecological consequences of habitat fragmentation and loss. We argue that accelerating climate change - the effective manipulation of time by humans - has generated a current need to build an equivalent framework for temporal ecology. Climate change has at once pressed ecologists to understand and predict ecological dynamics in non-stationary environments, while also challenged fundamental assumptions of many concepts, models and approaches. However, similarities between space and time, especially related issues of scaling, provide an outline for improving ecological models and forecasting of temporal dynamics, while the unique attributes of time, particularly its emphasis on events and its singular direction, highlight where new approaches are needed. We emphasise how a renewed, interdisciplinary focus on time would coalesce related concepts, help develop new theories and methods and guide further data collection. The next challenge will be to unite predictive frameworks from spatial and temporal ecology to build robust forecasts of when and where environmental change will pose the largest threats to species and ecosystems, as well as identifying the best opportunities for conservation. © 2014 John Wiley & Sons Ltd/CNRS.

Integration or Disintegration of the Ecological and Urban Functions of the River in the City? A Polish Perspective

OpenAIRE

Katarzyna KUBIAK-WÓJCICKA; Justyna CHODKOWSKA-MISZCZUK; Krzysztof ROGATKA

2018-01-01

This article aims to find whether the urbanized area experiences integration or disintegration of the ecological and urban functions of the river. The river has always played an important role in urban areas, although over the centuries, it has come through radical changes. At first, it decided on the location of the city, served as a defense and means of transport, and during the period of industrialization it became the technical base for the city. Currently, the river has again come to be ...

Developing conservation targets in social-ecological systems

Directory of Open Access Journals (Sweden)

Phillip S. Levin

2015-12-01

Full Text Available The development of targets is foundational in conservation. Although progress has been made in setting targets, the diverse linkages among ecological and social components make target setting for coupled social-ecological systems extremely challenging. Developing integrated social-ecological targets is difficult because it forces policy makers to consider how management actions propagate throughout social-ecological systems, and because ultimately it is society, not scientists, that defines targets. We developed an interdisciplinary approach for identifying management targets and illustrate this approach using an example motivated by Puget Sound, USA. Our approach blends ecological modeling with empirical social science to articulate trade-offs and reveal societal preferences for different social-ecological states. The framework aims to place information in the hands of decision makers and promote discussion in the appropriate forums. Our ultimate objective is to encourage the informed participation of citizens in the development of social-ecological targets that reflect their values while also protecting key ecosystem attributes.

Social-ecological resilience and geomorphic systems

Science.gov (United States)

Chaffin, Brian C.; Scown, Murray

2018-03-01

Governance of coupled social-ecological systems (SESs) and the underlying geomorphic processes that structure and alter Earth's surface is a key challenge for global sustainability amid the increasing uncertainty and change that defines the Anthropocene. Social-ecological resilience as a concept of scientific inquiry has contributed to new understandings of the dynamics of change in SESs, increasing our ability to contextualize and implement governance in these systems. Often, however, the importance of geomorphic change and geomorphological knowledge is somewhat missing from processes employed to inform SES governance. In this contribution, we argue that geomorphology and social-ecological resilience research should be integrated to improve governance toward sustainability. We first provide definitions of engineering, ecological, community, and social-ecological resilience and then explore the use of these concepts within and alongside geomorphology in the literature. While ecological studies often consider geomorphology as an important factor influencing the resilience of ecosystems and geomorphological studies often consider the engineering resilience of geomorphic systems of interest, very few studies define and employ a social-ecological resilience framing and explicitly link the concept to geomorphic systems. We present five key concepts-scale, feedbacks, state or regime, thresholds and regime shifts, and humans as part of the system-which we believe can help explicitly link important aspects of social-ecological resilience inquiry and geomorphological inquiry in order to strengthen the impact of both lines of research. Finally, we discuss how these five concepts might be used to integrate social-ecological resilience and geomorphology to better understand change in, and inform governance of, SESs. To compound these dynamics of resilience, complex systems are nested and cross-scale interactions from smaller and larger scales relative to the system of interest

Stable isotopes reveal diet shift from pre-extinction to reintroduced Przewalski's horses.

Science.gov (United States)

Kaczensky, Petra; Burnik Šturm, Martina; Sablin, Mikhail V; Voigt, Christian C; Smith, Steve; Ganbaatar, Oyunsaikhan; Balint, Boglarka; Walzer, Chris; Spasskaya, Natalia N

2017-07-20

The Przewalski's horse (Equus ferus przewalskii), the only remaining wild horse within the equid family, is one of only a handful of species worldwide that went extinct in the wild, was saved by captive breeding, and has been successfully returned to the wild. However, concerns remain that after multiple generations in captivity the ecology of the Przewalski's horse and / or the ecological conditions in its former range have changed in a way compromising the species' long term survival. We analyzed stable isotope chronologies from tail hair of pre-extinction and reintroduced Przewalski's horses from the Dzungarian Gobi and detected a clear difference in the isotopic dietary composition. The direction of the dietary shift from being a mixed feeder in winter and a grazer in summer in the past, to a year-round grazer nowadays, is best explained by a release from human hunting pressure. A changed, positive societal attitude towards the species allows reintroduced Przewalski's horses to utilize the scarce, grass-dominated pastures of the Gobi alongside local people and their livestock whereas their historic conspecifics were forced into less productive habitats dominated by browse.

SADA: Ecological Risk Based Decision Support System for Selective Remediation

Science.gov (United States)

Spatial Analysis and Decision Assistance (SADA) is freeware that implements terrestrial ecological risk assessment and yields a selective remediation design using its integral geographical information system, based on ecological and risk assessment inputs. Selective remediation ...

Apportioning sources of organic matter in streambed sediments: An integrated molecular and compound-specific stable isotope approach

Energy Technology Data Exchange (ETDEWEB)

Cooper, Richard J., E-mail: Richard.J.Cooper@uea.ac.uk [School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ (United Kingdom); Pedentchouk, Nikolai; Hiscock, Kevin M.; Disdle, Paul [School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ (United Kingdom); Krueger, Tobias [IRI THESys, Humboldt University, 10099 Berlin (Germany); Rawlins, Barry G. [British Geological Survey, Keyworth, Nottingham NG12 5GG (United Kingdom)

2015-07-01

apportionment of organic matter sources. Median organic matter contributions ranged from 22% to 52% for trees, 29% to 50% for herbaceous perennials, 17% to 34% for C{sub 3} graminoids and 3% to 7% for C{sub 4} graminoids. The results presented here clearly demonstrate the effectiveness of an integrated molecular and stable isotope analysis for quantitatively apportioning, with uncertainty, plant-specific organic matter contributions to streambed sediments via a Bayesian mixing model approach. - Highlights: • Organic contributions from trees, herbs and C{sub 3}/C{sub 4} graminoids are apportioned. • δ{sup 2}H provides strong discrimination between plant functional types. • δ{sup 13}C provides strong contrasts between C{sub 3} and C{sub 4} plants. • δ{sup 2}H and δ{sup 13}C values could not differentiate aquatic and terrestrial species. • n-Alkane ratios compliment isotopic discrimination.

Satellite tracking and stable isotope analysis link wintering and feeding grounds of North Atlantic baleen whales

NARCIS (Netherlands)

e Silva, Monica Almeida; Prieto, Rui; Gauffier, Pauline; Palsboll, Per; Bérubé, Martine; Colaco, Ana

2017-01-01

Knowledge of the distribution of baleen whales throughout their annual cycle is critical for understanding their ecology, life history and behavior, and for their effective conservation. We combined analysis of stable isotopes (δ15N and δ13C) and satellite tracking data of blue (Balaenoptera

Evaluating the use of strontium isotopes in tree rings to record the isotopic signal of dust deposited on the Wasatch Mountains

International Nuclear Information System (INIS)

Miller, Olivia L.; Solomon, Douglas Kip; Fernandez, Diego P.; Cerling, Thure E.; Bowling, David R.

2014-01-01

Highlights: • Dust was a major contributor of Sr to soil and tree rings over Sr poor bedrocks. • Tree rings were evaluated for their use as a record of dust strontium isotope history. • The isotopic signal of dust deposited on the Wasatch Mountains changed over the past ∼75 years. - Abstract: Dust cycling from the Great Basin to the Rocky Mountains is an important component of ecological and hydrological processes. We investigated the use of strontium (Sr) concentrations and isotope ratios ( 87 Sr/ 86 Sr) in tree rings as a proxy for dust deposition. We report Sr concentrations and isotope ratios ( 87 Sr/ 86 Sr) from atmospherically deposited dust, soil, bedrock, and tree rings from the Wasatch Mountains to investigate provenance of dust landing on the Wasatch Mountains and to determine if a dust Sr record is preserved in tree rings. Trees obtained a majority of their Sr from dust, making them a useful record of dust source and deposition. Dust contributions of Sr to soils were more than 94% over quartzite, 63% over granodiorite, and 50% over limestone. Dust contributions of Sr to trees were more than 85% in trees growing over quartzite, 55% over granodiorite, and between 0% and 92% over limestone. These findings demonstrate that a dust signal was preserved in some tree rings and reflects how Sr from dust and bedrock mixes within the soil. Trees growing over quartzite were most sensitive to dust. Changes in Sr isotope ratios for a tree growing over quartzite were interpreted as changes in dust source over time. This work has laid the foundation for using tree rings as a proxy for dust deposition over time

Research on the Mechanism of Cross Regional Grassland Ecological Compensation

Science.gov (United States)

Yang, Ran; Ma, Jun

2018-01-01

In recent years, grassland environmental damage has become serious, and grassland resources protection task has become heavy, grassland ecological compensation has become an effective way to solve this problem; but the current grassland ecological compensation standards were low, the effect is poor. The fundamental reason is the model of administrative division destroys the integrity of grassland. Based on the analysis of the status quo of grassland compensation, this paper tries to protect the grassland integrity, breaks the administrative division restriction, implements the space regulation, constructs the framework of cross-regional grassland ecological compensation mechanism, describes its operation process. It provides new way to realize the sustainable development of the grassland environment.

Isotopic incorporation rates and discrimination factors in mantis shrimp crustaceans.

Directory of Open Access Journals (Sweden)

Maya S deVries

Full Text Available Stable isotope analysis has provided insights into the trophic ecology of a wide diversity of animals. Knowledge about isotopic incorporation rates and isotopic discrimination between the consumer and its diet for different tissue types is essential for interpreting stable isotope data, but these parameters remain understudied in many animal taxa and particularly in aquatic invertebrates. We performed a 292-day diet shift experiment on 92 individuals of the predatory mantis shrimp, Neogonodactylus bredini, to quantify carbon and nitrogen incorporation rates and isotope discrimination factors in muscle and hemolymph tissues. Average isotopic discrimination factors between mantis shrimp muscle and the new diet were 3.0 ± 0.6 ‰ and 0.9 ± 0.3 ‰ for carbon and nitrogen, respectively, which is contrary to what is seen in many other animals (e.g. C and N discrimination is generally 0-1 ‰ and 3-4 ‰, respectively. Surprisingly, the average residence time of nitrogen in hemolymph (28.9 ± 8.3 days was over 8 times longer than that of carbon (3.4 ± 1.4 days. In muscle, the average residence times of carbon and nitrogen were of the same magnitude (89.3 ± 44.4 and 72.8 ± 18.8 days, respectively. We compared the mantis shrimps' incorporation rates, along with rates from four other invertebrate taxa from the literature, to those predicted by an allometric equation relating carbon incorporation rate to body mass that was developed for teleost fishes and sharks. The rate of carbon incorporation into muscle was consistent with rates predicted by this equation. Our findings provide new insight into isotopic discrimination factors and incorporation rates in invertebrates with the former showing a different trend than what is commonly observed in other animals.

Fit in the Body: Matching Embodied Cognition with Social-Ecological Systems

Directory of Open Access Journals (Sweden)

Janne I. Hukkinen

2012-12-01

Full Text Available Analysis of fit has focused on the macrolevel fit between social institutions and ecosystems, and bypassed the microlevel fit between individual cognition and its socio-material environment. I argue that the conceptualizations we develop about social-ecological systems and our position in them should be understood as ways for a fundamentally cognitive organism to adapt to particular social and ecological situations. Since at issue is our survival as a species, we need to better understand the structure and dynamics of fit between human cognition and its social-ecological environment. I suggest that the embodied cognition perspective opens up possibilities for "nudging" evolution through the conceptual integration of the cognitively attractive but ecologically unrealistic neoclassical economics, and the cognitively less attractive but ecologically more realistic adaptive cycle theory (panarchy. The result is a conceptually integrated model, the Roller Coaster Blend, which expresses in metaphorical terms why competitive individuals are better off cooperating than competing with each other in the face of absolute resource limits. The blend enables the reframing of messages about the limits of the social-ecological system in terms of growth rather than degrowth. This is cognitively appealing, as upward growth fires in our minds the neural connections of "more," "control", and "happy." The blend's potential for nudging behavior arises from its autopoietic characteristic: it can be both an account of the social-ecological system as an emergent structure that is capable of renewing itself, and a cognitive attractor of individuals whose recruitment reinforces the integrity of the social-ecological system.

Application of isotope techniques to investigate groundwater pollution

International Nuclear Information System (INIS)

1998-10-01

This publication is a compilation of scientific results from the Co-ordinated Research Project (CRP) on the Application of Isotope Techniques to Investigate Groundwater Pollution which was implemented from 1995 to 1997. The conclusions of the CRP were presented by scientists from the following participating Member States: Austria, Brazil, China, Czech Republic, France, Hungary, India, Israel, Italy, New Zealand, Pakistan, Poland, Senegal and the United Kingdom. The CRP was implemented in recognition of the importance of protecting groundwater resources, and promoting the role of isotope techniques when integrated to classical hydrological methods to identify the sources and mechanisms of by which pollution takes place. The results of the CRP are expected to find practical applications in tackling hydrological problems encountered in technical co-operation projects of the IAEA. This publication could also provide a contribution toward the continuing efforts of various sectors to investigate, mitigate and control the threat of groundwater pollution. This publication includes the results of 16 investigations dealing with isotopes of hydrogen, carbon, nitrogen, oxygen and sulfur integrated to some extent with the classical hydrological tools of investigation. Each document in this compilation is provided with abstract and index

[Ecology and ecologies].

Science.gov (United States)

Valera, Luca

2011-01-01

Ecology (from the Greek words οιχοσ, "house" and λογια "study of") is the science of the "house", since it studies the environments where we live. There are three main ways of thinking about Ecology: Ecology as the study of interactions (between humans and the environment, between humans and living beings, between all living beings, etc.), Ecology as the statistical study of interactions, Ecology as a faith, or rather as a science that requires a metaphysical view. The history of Ecology shows us how this view was released by the label of "folk sense" to gain the epistemological status of science, a science that strives to be interdisciplinary. So, the aim of Ecology is to study, through a scientific methodology, the whole natural world, answering to very different questions, that arise from several fields (Economics, Biology, Sociology, Philosophy, etc.). The plurality of issues that Ecology has to face led, during the Twentieth-century, to branch off in several different "ecologies". As a result, each one of these new approaches chose as its own field a more limited and specific portion of reality.

A proposed standard on medical isotope production in fission reactors

International Nuclear Information System (INIS)

Schenter, R. E.; Brown, G. J.; Holden, C. S.

2006-01-01

Authors Robert E. Sehenter, Garry Brown and Charles S. Holden argue that a Standard for 'Medical Isotope Production' is needed. Medical isotopes are becoming major components of application for the diagnosis and treatment of all the major diseases including all forms of cancer, heart disease, arthritis, Alzheimer's, among others. Current nuclear data to perform calculations is incomplete, dated or imprecise or otherwise flawed for many isotopes that could have significant applications in medicine. Improved data files will assist computational analyses to design means and methods for improved isotope production techniques in the fission reactor systems. Initial focus of the Standard is expected to be on neutron cross section and branching data for both fast and thermal reactor systems. Evaluated and reviewed tables giving thermal capture cross sections and resonance integrals for the major target and product medical isotopes would be the expected 'first start' for the 'Standard Working Group'. (authors)

Fossil mice and rats show isotopic evidence of niche partitioning and change in dental ecomorphology related to dietary shift in Late Miocene of Pakistan.

Science.gov (United States)

Kimura, Yuri; Jacobs, Louis L; Cerling, Thure E; Uno, Kevin T; Ferguson, Kurt M; Flynn, Lawrence J; Patnaik, Rajeev

2013-01-01

Stable carbon isotope analysis in tooth enamel is a well-established approach to infer C3 and C4 dietary composition in fossil mammals. The bulk of past work has been conducted on large herbivorous mammals. One important finding is that their dietary habits of fossil large mammals track the late Miocene ecological shift from C3 forest and woodland to C4 savannah. However, few studies on carbon isotopes of fossil small mammals exist due to limitations imposed by the size of rodent teeth, and the isotopic ecological and dietary behaviors of small mammals to climate change remain unknown. Here we evaluate the impact of ecological change on small mammals by fine-scale comparisons of carbon isotope ratios (δ(13)C) with dental morphology of murine rodents, spanning 13.8 to ∼2.0 Ma, across the C3 to C4 vegetation shift in the Miocene Siwalik sequence of Pakistan. We applied in-situ laser ablation GC-IRMS to lower first molars and measured two grazing indices on upper first molars. Murine rodents yield a distinct, but related, record of past ecological conditions from large herbivorous mammals, reflecting available foods in their much smaller home ranges. In general, larger murine species show more positive δ(13)C values and have higher grazing indices than smaller species inhabiting the same area at any given age. Two clades of murine rodents experienced different rates of morphological change. In the faster-evolving clade, the timing and trend of morphological innovations are closely tied to consumption of C4 diet during the vegetation shift. This study provides quantitative evidence of linkages among diet, niche partitioning, and dental morphology at a more detailed level than previously possible.

Fossil Mice and Rats Show Isotopic Evidence of Niche Partitioning and Change in Dental Ecomorphology Related to Dietary Shift in Late Miocene of Pakistan

Science.gov (United States)

Kimura, Yuri; Jacobs, Louis L.; Cerling, Thure E.; Uno, Kevin T.; Ferguson, Kurt M.; Flynn, Lawrence J.; Patnaik, Rajeev

2013-01-01

Stable carbon isotope analysis in tooth enamel is a well-established approach to infer C3 and C4 dietary composition in fossil mammals. The bulk of past work has been conducted on large herbivorous mammals. One important finding is that their dietary habits of fossil large mammals track the late Miocene ecological shift from C3 forest and woodland to C4 savannah. However, few studies on carbon isotopes of fossil small mammals exist due to limitations imposed by the size of rodent teeth, and the isotopic ecological and dietary behaviors of small mammals to climate change remain unknown. Here we evaluate the impact of ecological change on small mammals by fine-scale comparisons of carbon isotope ratios (δ13C) with dental morphology of murine rodents, spanning 13.8 to ∼2.0 Ma, across the C3 to C4 vegetation shift in the Miocene Siwalik sequence of Pakistan. We applied in-situ laser ablation GC-IRMS to lower first molars and measured two grazing indices on upper first molars. Murine rodents yield a distinct, but related, record of past ecological conditions from large herbivorous mammals, reflecting available foods in their much smaller home ranges. In general, larger murine species show more positive δ13C values and have higher grazing indices than smaller species inhabiting the same area at any given age. Two clades of murine rodents experienced different rates of morphological change. In the faster-evolving clade, the timing and trend of morphological innovations are closely tied to consumption of C4 diet during the vegetation shift. This study provides quantitative evidence of linkages among diet, niche partitioning, and dental morphology at a more detailed level than previously possible. PMID:23936324

Fossil mice and rats show isotopic evidence of niche partitioning and change in dental ecomorphology related to dietary shift in Late Miocene of Pakistan.

Directory of Open Access Journals (Sweden)

Yuri Kimura

Full Text Available Stable carbon isotope analysis in tooth enamel is a well-established approach to infer C3 and C4 dietary composition in fossil mammals. The bulk of past work has been conducted on large herbivorous mammals. One important finding is that their dietary habits of fossil large mammals track the late Miocene ecological shift from C3 forest and woodland to C4 savannah. However, few studies on carbon isotopes of fossil small mammals exist due to limitations imposed by the size of rodent teeth, and the isotopic ecological and dietary behaviors of small mammals to climate change remain unknown. Here we evaluate the impact of ecological change on small mammals by fine-scale comparisons of carbon isotope ratios (δ(13C with dental morphology of murine rodents, spanning 13.8 to ∼2.0 Ma, across the C3 to C4 vegetation shift in the Miocene Siwalik sequence of Pakistan. We applied in-situ laser ablation GC-IRMS to lower first molars and measured two grazing indices on upper first molars. Murine rodents yield a distinct, but related, record of past ecological conditions from large herbivorous mammals, reflecting available foods in their much smaller home ranges. In general, larger murine species show more positive δ(13C values and have higher grazing indices than smaller species inhabiting the same area at any given age. Two clades of murine rodents experienced different rates of morphological change. In the faster-evolving clade, the timing and trend of morphological innovations are closely tied to consumption of C4 diet during the vegetation shift. This study provides quantitative evidence of linkages among diet, niche partitioning, and dental morphology at a more detailed level than previously possible.

Using stable isotopes to investigate individual diet specialization in California sea otters (Enhydra lutris nereis)

Science.gov (United States)

Newsome, S.D.; Tinker, M.T.; Monson, Daniel H.; Oftedal, O.T.; Ralls, K.; Staedler, M.M.; Fogel, M.L.; Estes, J.A.

2009-01-01

Differences in diet composition among conspecifics (dietary specialization) have been documented across a broad range of taxonomic groups and habitats, and such variation at the individual level is increasingly recognized as an important component of diversity in trophic interactions. Accurate identification of individual dietary specialization, however, requires longitudinal dietary records that are labor-intensive and cost-prohibitive to obtain for many species. Here we explore the use of stable isotopes (δ13C and δ15N) as a promising technique for detecting and quantifying patterns of individual dietary specialization. Southern sea otters (Enhydra lutris nereis) offer a unique opportunity for testing this approach because (1) they consume a wide variety of prey that span multiple trophic levels, habitats, and ecologically defined functional groups; and (2) individual diet specialization can be validated with existing observational data. We analyzed the isotopic composition of sea otter vibrissae (n = 31) in order to characterize inter- and intra-individual variation in sea otter diets at Monterey Bay, California, USA. At the population level, sea otters showed substantial variation in both δ13C and δ15N values, occupying nearly all of the “isotopic space” created by the diversity of isotopic signatures of potential prey taxa. Most of the variation in sea otter vibrissae was accounted for by differences between individuals, with much less contributed by within-individual variation. A majority of sea otters (∼80%) showed relatively little temporal variability in isotopic composition, suggesting that the proportional composition of most individuals' diets is relatively constant over time; a few individuals (∼20%) exhibited a high degree of intra-vibrissa isotopic variability, suggesting seasonal shifts in diet composition. These results and our interpretation of them were supported by long-term observational data on the diets of radio-tagged sea otters

Including Overweight or Obese Students in Physical Education: A Social Ecological Constraint Model

Science.gov (United States)

Li, Weidong; Rukavina, Paul

2012-01-01

In this review, we propose a social ecological constraint model to study inclusion of overweight or obese students in physical education by integrating key concepts and assumptions from ecological constraint theory in motor development and social ecological models in health promotion and behavior. The social ecological constraint model proposes…

Integrating traditional ecological knowledge with western science for optimal natural resource management

Science.gov (United States)

Serra J. Hoagland

2017-01-01

Traditional ecological knowledge (TEK) has been recognized within indigenous communities for millennia; however, traditional ecological knowledge has received growing attention within the western science (WS) paradigm over the past twenty-five years. Federal agencies, national organizations, and university programs dedicated to natural resource management are beginning...

Coupling Intensive Land Use and Landscape Ecological Security for Urban Sustainability: An Integrated Socioeconomic Data and Spatial Metrics Analysis in Hangzhou City

Directory of Open Access Journals (Sweden)

Xiaoteng Cen

2015-01-01

Full Text Available Despite the unprecedented rate of urbanization throughout the world, human society is still facing the challenge of coordinating urban socioeconomic development and ecological conservation. In this article, we integrated socioeconomic data and spatial metrics to investigate the coupling relationship between intensive land use (ILU system and landscape ecological security (LES system for urban sustainable development, and to determine how these systems interact with each other. The values of ILU and LES were first calculated according to two evaluation subsystems under the pressure-state-response (PSR framework. A coupling model was then established to analyze the coupling relationship within these two subsystems. The results showed that the levels of both subsystems were generally increasing, but there were several fluctuation changes in LES. The interaction in each system was time lagged; urban land use/cover change (LUCC and ecosystem transformation were determined by political business cycles and influenced by specific factors. The coupling relationship underwent a coordinated development mode from 1992–2012. From the findings we concluded that the coupling system maintained a stable condition and underwent evolving threshold values. The integrated ILU and LES system was a coupling system in which subsystems were related to each other and internal elements had mutual effects. Finally, it was suggested that our results provided a multi-level interdisciplinary perspective on linking socioeconomic-ecological systems. The implications for urban sustainable development were also discussed.

Trophic niche of squids: Insights from isotopic data in marine systems worldwide

Science.gov (United States)

Navarro, Joan; Coll, Marta; Somes, Christoper J.; Olson, Robert J.

2013-10-01

Cephalopods are an important prey resource for fishes, seabirds, and marine mammals, and are also voracious predators on crustaceans, fishes, squid and zooplankton. Because of their high feeding rates and abundance, squids have the potential to exert control on the recruitment of commercially important fishes. In this review, we synthesize the available information for two intrinsic markers (δ15N and δ13C isotopic values) in squids for all oceans and several types of ecosystems to obtain a global view of the trophic niches of squids in marine ecosystems. In particular, we aimed to examine whether the trophic positions and trophic widths of squid species vary among oceans and ecosystem types. To correctly compare across systems, we adjusted squid δ15N values for the isotopic variability of phytoplankton at the base of the food web provided by an ocean circulation-biogeochemistry-isotope model. Studies that focused on the trophic ecology of squids using isotopic techniques were few, and most of the information on squids was from studies on their predators. Our results showed that squids occupy a large range of trophic positions and exploit a large range of trophic resources, reflecting the versatility of their feeding behavior and confirming conclusions from food-web models. Clear differences in both trophic position and trophic width were found among oceans and ecosystem types. The study also reinforces the importance of considering the natural variation in isotopic values when comparing the isotopic values of consumers inhabiting different ecosystems.

Paleoecological and climatic implications of stable isotope results from late Pleistocene bone collagen, Ziegeleigrube Coenen, Germany

Science.gov (United States)

Wißing, Christoph; Matzerath, Simon; Turner, Elaine; Bocherens, Hervé

2015-07-01

Climatic and ecological conditions during Marine Oxygen Isotope Stage (MIS) 3 are complex and the impact of cold spells on the ecosystems in Central Europe still needs to be investigated thoroughly. Ziegeleigrube Coenen (ZC) is a late Pleistocene MIS 3 locality in the Lower Rhine Embayment of Germany, radiocarbon-dated to > 34 14C ka BP. The site yielded a broad spectrum of mammal species. We investigated the carbon (δ13C), nitrogen (δ15N) and sulfur (δ34S) isotope signatures of bone collagen, since these are valuable tools in characterizing ecological niches, environmental conditions and aspects of climate and mobility. By comparison with pre- and post-Last Glacial Maximum (LGM) sites in Central Europe we show that ZC belongs in a cold event of MIS 3 and was climatically more similar to post-LGM sites than to pre-LGM sites. However, the trophic structure resembled that of typical pre-LGM sites in Belgium. This cold event in MIS 3 changed the bottom of the foodweb, but do not seem to have had a direct impact on the occurrence of the mammalian species and their ecological distribution. Apparently the (mega-) faunal community could adapt also to harsher environmental conditions during MIS 3.

The Cultural Ecology Protection and Management of Urban Forests in China

OpenAIRE

ZHANG, Ying; SONG, Weiming; CHEN, Ke; GUO, Chunjing

2013-01-01

Forests have economic, ecological, social and cultural functions. Forests Cultural ecology, the counterpart of forest ecology， is the integration of human spirit formed on the basis of natural forest and living systems. In recent years, China's urbanization rate has increased from 28% in 1993 to 45.68% in 2008, and ecological protection of urban forest has made great progress, but insufficient attention was paid to the forest cultural ecology protection and the relevant regulatory was not w...

Use of an isotope separator at the INEL

International Nuclear Information System (INIS)

Anderl, R.A.

1977-01-01

An electromagnetic isotope separator with a retardation lens as a collector was used to prepare highly enriched samples of Nd-143, -144, -145, -146, -148, -150, Sm-147, -149; Eu-151, -152, -153, -154. The 50 μg to 75 μg samples, deposited on 1 mil nickel foil or 0.5 mil vanadium foil, are part of a sample set to be irradiated in EBR-II as part of an integral-capture cross-section measurement program at the INEL. The isotope separator and the apparatus used for the sample preparation are described

Isotopic niches of fishes in coastal, neritic and oceanic waters off Adélie land, Antarctica

Science.gov (United States)

Cherel, Yves; Koubbi, Philippe; Giraldo, Carolina; Penot, Florian; Tavernier, Eric; Moteki, Masato; Ozouf-Costaz, Catherine; Causse, Romain; Chartier, Amélie; Hosie, Graham

2011-08-01

We used the stable isotope method to investigate the ecological niches of Antarctic fishes, with δ 13C and δ 15N as proxies of fish habitats and dietary habits, respectively. Muscle isotopic signature was measured for each of 237 delipidated tissue samples from 27 fish species collected offshore Adélie Land, East Antarctica. Overall, δ 13C values ranged from -25.3‰ to -18.2‰, thus allowing characterizing of the fish habitats, with inshore/benthic species having more positive δ 13C signatures than offshore/pelagic ones. No clear difference in the δ 13C values of pelagic fishes was found between species living in neritic and oceanic waters. Overall, the δ 15N signatures of neritic pelagic and epibenthic fishes encompassed ˜1.0 trophic level (3.1‰), a higher difference than that (1.4‰) found within the oceanic assemblage. Fishes with the lowest and highest δ 15N values are primarily invertebrate- and fish-eaters, respectively. The isotopic niches of fishes illustrate the different mechanisms allowing coexistence, with most fishes segregating at least by one of the two niche axes (δ 13C and δ 15N). Muscle isotopic values also document interindividual foraging specialization over the long-term in coastal benthic fishes, but not in more offshore pelagic species. Finally, the δ 15N signatures of fishes overlap with those of penguins and seals, indicating that seabirds and marine mammals share the upper levels of the Antarctic pelagic ecosystem with some large fish species. In conclusion, the concept of isotopic niche is a powerful tool to investigate various aspects of the ecological niche of Antarctic fishes, thus complementing the use of other conventional and non-conventional approaches.

Ecologically Sound Procedural Generation of Natural Environments

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Benny Onrust

2017-01-01

Full Text Available Current techniques for the creation and exploration of virtual worlds are largely unable to generate sound natural environments from ecological data and to provide interactive web-based visualizations of such detailed environments. We tackle this challenge and propose a novel framework that (i explores the advantages of landscape maps and ecological statistical data, translating them to an ecologically sound plant distribution, and (ii creates a visually convincing 3D representation of the natural environment suitable for its interactive visualization over the web. Our vegetation model improves techniques from procedural ecosystem generation and neutral landscape modeling. It is able to generate diverse ecological sound plant distributions directly from landscape maps with statistical ecological data. Our visualization model integrates existing level of detail and illumination techniques to achieve interactive frame rates and improve realism. We validated with ecology experts the outcome of our framework using two case studies and concluded that it provides convincing interactive visualizations of large natural environments.

Towards an Ecological Inquiry in Child-Computer Interaction

DEFF Research Database (Denmark)

Smith, Rachel Charlotte; Iversen, Ole Sejer; Hjermitslev, Thomas

2013-01-01

The paper introduces an Ecological Inquiry as a methodological approach for designing technology with children. The inquiry is based on the ‘ecological turn’ in HCI, Ubiquitous Computing and Participatory Design that shift the emphasis of design from technological artifacts to entire use ecologies...... into which technologies are integrated. Our Ecological Inquiry extends Cooperative Inquiry in three directions: from understanding to emergence of social practices and meanings, from design of artifacts to hybrid environments, and from a focus on technology to appropriations through design and use. We...... exemplify our approach in a case study in which we designed social technologies for hybrid learning environments with children in two schools, and discuss how an Ecological Inquiry can inform existing approaches in CCI....

Ecology and IPM of Insects at Grain Elevators

Science.gov (United States)

Cost-effectiveness of insect pest management depends upon its integration with other elevator operations. Successful integration may require consideration of insect ecology. Field infestation has not been observed for grain received at elevators. Grain may be infested during harvest by residual inse...

Ecological risks of biological control agents: impacts on IPM

NARCIS (Netherlands)

Hokkanen, H.M.T.; Lenteren, van J.C.; Menzler-Hokkanen, I.

2007-01-01

Since the early days of integrated pest management a sound ecological foundation has been considered essential for the development of effective systems. From time to time, there have been attempts to evaluate the ways in which ecological theory is exploited in pest control, and to review the lessons

The Effect of Parasite Infection on Stable Isotope Turnover Rates of δ15N, δ13C and δ34S in Multiple Tissues of Eurasian Perch Perca fluviatilis.

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Elizabeth Yohannes

Full Text Available Stable isotope analysis of commercially and ecologically important fish can improve understanding of life-history and trophic ecology. However, accurate interpretation of stable isotope values requires knowledge of tissue-specific isotopic turnover that will help to describe differences in the isotopic composition of tissues and diet. We performed a diet-switch experiment using captive-reared parasite-free Eurasian perch (Perca fluviatilis and wild caught specimens of the same species, infected with the pike tapeworm Triaenophorus nodulosus living in host liver tissue. We hypothesize that metabolic processes related to infection status play a major role in isotopic turnover and examined the influence of parasite infection on isotopic turn-over rate of carbon (δ13C, nitrogen (δ15N and sulphur (δ34S in liver, blood and muscle. The δ15N and δ13C turnovers were fastest in liver tissues, followed by blood and muscle. In infected fish, liver and blood δ15N and δ13C turnover rates were similar. However, in infected fish, liver and blood δ13C turnover was faster than that of δ15N. Moreover, in infected subjects, liver δ15N and δ13C turnover rates were three to five times faster than in livers of uninfected subjects (isotopic half-life of ca.3-4 days compared to 16 and 10 days, respectively. Blood δ34S turnover rate were about twice faster in non-infected individuals implying that parasite infection could retard the turnover rate of δ34S and sulphur containing amino acids. Slower turnover rate of essential amino acid could probably decrease individual immune function. These indicate potential hidden costs of chronic and persistent infections that may have accumulated adverse effects and might eventually impair life-history fitness. For the first time, we were able to shift the isotope values of parasites encapsulated in the liver by changing the dietary source of the host. We also report variability in isotopic turnover rates between tissues

Distinguishing ectomycorrhizal and saprophytic fungi using carbon and nitrogen isotopic compositions

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Weiguo Hou

2012-05-01

Full Text Available Ectomycorrhizal fungi, a group of widespread symbiotic fungi with plant, obtain carbon source from trees and improve plant mineral nutrient uptake with their widespread hyphal network. Ectomycorrhizal fungi can be used as inoculants to improve the survival rates of plantation. Saprophytic fungi use the nutrition from the debris of plant or animals, and it is difficult to distinguish the saprophytic and ectomycorrhizal fungi by morphological and anatomic methods. In this research, the differences of stable carbon and nitrogen isotopic compositions of these fungi were analyzed. The results showed that the abundances of 13C of were higher than those of ectomycorrhizal fungi and the abundances of 15N of saprophytic fungi were lower than those of ectomycorrhizal fungi. Such differences of stable carbon and nitrogen isotopic compositions between ectomycorrhizal fungi and saprophytic fungi can be ascribed to their different nutrition sources and ecological functions. These results collectively indicate that stable carbon and nitrogen isotopic compositions are an effective proxy for distinguishing between ectomycorrhizal and saprophytic fungi.

Investigating Pathways of Nutrient and Energy Flows Through Aquatic Food Webs Using Stable Isotopes of Carbon and Nitrogen

Energy Technology Data Exchange (ETDEWEB)

Hadwen, W. L.; Bunn, S. E. [Australian Rivers Institute, Griffith School of Environment, Griffith University, Nathan Campus, Brisbane, Queensland (Australia)

2013-05-15

Carbon and nitrogen stable isotopes can provide valuable insights into pathways of nutrient and energy flows in aquatic ecosystems. Carbon stable isotopes are principally used to trace pathways of organic matter transfer through aquatic food webs, particularly with regard to identifying the dominant sources of nutrition for aquatic biota. Stable isotopes of carbon have been widely used to answer one of the most pressing questions in aquatic food web ecology - to what degree do in-stream (autochthonous) and riparian (allochthonous) sources of energy fuel riverine food webs? In conjunction with carbon stable isotopes, nitrogen stable isotopes have been used to determine the trophic position of consumers and to identify the number of trophic levels in aquatic food webs. More recently, stable nitrogen isotopes have been recommended as indicators of anthropogenic disturbances. Specifically, agricultural land uses and/or sewage effluent discharge have been shown to significantly increase {delta}{sup 15}N signatures in primary producers and higher order consumers in freshwater, estuarine and marine environments. Together, carbon and nitrogen stable isotopes can be used to examine natural food web functions as well as the degree to which human modifications to catchments and aquatic environments can influence aquatic ecosystem function. (author)

Nd isotopes and crustal growth rate

International Nuclear Information System (INIS)

Albarede, F.

1988-01-01

Sm/Nd isotopic constraints on crustal growth is discussed. In order to constrain Sm/Nd fractionation between continental crust and depleted mantle, an extensive data base of isotopic measurements (assumed to be adequately representative of continental crust) was compiled. The results imply that the evolution of depleted mantles was roughly linear, with no major discontinuities over the course of geologic time. This is different from other determinations of depleting mantle evolution, which show nonlinear behavior. The Sm/Nd evolution lines for continental crust and depleted mantle intersect between 3.8 to 4.0 Ga, which may indicate that the onset of continental growth was later than 4.5 Ga. A mathematical model is described, the results of which imply that time integrated crustal additions from the mantle are about 1.8 to 2.5 cu km/a, whereas crustal subtractions by sediment recycling are about 0.6 to 1.5 cu km/a. This results in a net time integrated crustal growth rate of about 1 cu km/a, which is similar to present day rates determined, for example, by Reymer and Schubert

Framework for integration of urban planning, strategic environmental assessment and ecological planning for urban sustainability within the context of China

International Nuclear Information System (INIS)

He Jia; Bao Cunkuan; Shu Tingfei; Yun Xiaoxue; Jiang Dahe; Brwon, Lex

2011-01-01

Sustainable development or sustainability has been highlighted as an essential principle in urban master planning, with increasing recognition that uncontrollable urbanization may well give rise to various issues such as overexploitation of natural resources, ecosystem destruction, environmental pollution and large-scale climate change. Thus, it is deemed necessary to modify the existing urban and regional administrative system so as to cope with the challenges urban planning is being confronted with and realize the purpose of urban sustainability. This paper contributed to proposing a mechanism which helps to make urban planning with full consideration of issues with respect to sustainable development. We suggested that the integration of urban planning, SEA and ecological planning be a multi-win strategy to offset deficiency of each mentioned political tool being individually applied. We also proposed a framework where SEA and ecological planning are fully incorporated into urban planning, which forms a two-way constraint mechanism to ascertain environmental quality of urban planning, although in practice, planning and SEA processes may conditionally be unified. Moreover, as shown in the case study, the integration of the three political tools may be constrained due to slow changes in the contextual factors, in particular the political and cultural dimensions. Currently within the context of China, there may be three major elements which facilitate integration of the three political tools, which are (1) regulatory requirement of PEIA on urban planning, (2) the promotion or strong administrative support from government on eco-district building, and (3) the willingness of urban planners to collaborate with SEA experts or ecologists.

Botanical aspects of the ecological integrity of a radioactive waste disposal site

International Nuclear Information System (INIS)

Hall, A.V.

1986-01-01

Botanical factors play a key role in maintaining the long term integrity of ecosystems. The results of botanical research at the Vaalputs radioactive waste disposal site in Bushmanland, South Africa, are outlined. Vaalputs is in an arid region and its vegetation is a patchy mosaic of low shrub and grass communities. Soil variation from site to site is the main determinant of community structure and erratic precipitation is a major stochastic forcing factor. Management measures to conserve taxa, ecosystems and local genetic biogeography are discussed in relation to natural and artificial disturbances which may occur over long time-scales. Restoration of vegetation over the burial trenches should as far as possible be to the site's former ecotypes except that deep-rooted species should be excluded. Precautions should be taken against the accidental establishment of exotic plant invaders at Vaalputs especially if they are deep-rooted. More is now known about plant ecology at Vaalputs than any other part of Bushmanland. It would be valuable to develop such studies further and establish Vaalputs as a permanent reserve for arid-zone biological research

Conceptual ecological models to guide integrated landscape monitoring of the Great Basin

Science.gov (United States)

Miller, D.M.; Finn, S.P.; Woodward, Andrea; Torregrosa, Alicia; Miller, M.E.; Bedford, D.R.; Brasher, A.M.

2010-01-01

The Great Basin Integrated Landscape Monitoring Pilot Project was developed in response to the need for a monitoring and predictive capability that addresses changes in broad landscapes and waterscapes. Human communities and needs are nested within landscapes formed by interactions among the hydrosphere, geosphere, and biosphere. Understanding the complex processes that shape landscapes and deriving ways to manage them sustainably while meeting human needs require sophisticated modeling and monitoring. This document summarizes current understanding of ecosystem structure and function for many of the ecosystems within the Great Basin using conceptual models. The conceptual ecosystem models identify key ecological components and processes, identify external drivers, develop a hierarchical set of models that address both site and landscape attributes, inform regional monitoring strategy, and identify critical gaps in our knowledge of ecosystem function. The report also illustrates an approach for temporal and spatial scaling from site-specific models to landscape models and for understanding cumulative effects. Eventually, conceptual models can provide a structure for designing monitoring programs, interpreting monitoring and other data, and assessing the accuracy of our understanding of ecosystem functions and processes.

Diet-tissue stable isotope (delta¹³C and delta¹⁵N) discrimination factors for multiple tissues from terrestrial reptiles (rock iguanas, Cyclura species)

OpenAIRE

Steinitz, Ronnie

2015-01-01

Trophic interactions can drive community structure; therefore, studying food webs is key in understanding ecological communities. Stable isotope analysis is a powerful tool for reconstructing foraging patterns. However, stable isotope discrimination factors (delta¹³C and delta¹⁵N) are needed to best use this tool. We determined the first delta¹³C and delta¹⁵N values for Rock Iguanas (Cyclura spp.) to better understand isotope fractionation patterns in reptiles and estimate wild reptile diets....

Stable Isotopic Composition of Rainfall in Western Cameroon

Energy Technology Data Exchange (ETDEWEB)

Ketchemen-Tandia, B.; Ngo Boum, S.; Ebonji Seth, C. R.; Nkoue Ndong, G. R.; Wonkam, C. [Universite de Douala, Douala (Cameroon); Huneau, F. [Universite de Bordeaux, EA Georessources and Environnement, Talence (France); Celle-Jeanton, H. [Clermont Universite, Clermont-Ferrand (France)

2013-07-15

Monthly rainfall collected at the douala station (Western cameroon) from 2006 to 2008 was analysed for oxygen-18 and deuterium content. The dataset, which is now integrated into the GNIP database, was compared to the local groundwater record in order to define the input function of regional hydrosystems. The isotope data displays a wide range of values from -0.59 to -6.14 per mille for oxygen-18 and from -7.75 to -38.8 per mille for deuterium, closely following the GMWL (global Meteoric Water line), suggesting that rain formation processes occurred under isotopic equilibrium conditions between the condensate and the corresponding vapour. No significant evaporation tendency was found. The comparison with the previous studies in the area provides a realistic pattern of isotope concentrations in both surface and groundwater throughout Cameroon. (author)

European ecological networks and greenways

NARCIS (Netherlands)

Jongman, R.H.G.; Külvik, M.; Kristiansen, I.

2004-01-01

In the context of European integration, networks are becoming increasingly important in both social and ecological sense. Since the beginning of the 1990s, societal and scientific exchanges are being restructured as the conceptual approaches towards new nature conservation strategies have been

Spanish Network for Isotopes in Precipitation: Isotope Spatial distribution and contribution to the knowledge of the hydrological cycle

International Nuclear Information System (INIS)

Diaz-Teijeiro, M. F.; Rodriguez-Arevalo, J.; Castano, S.

2009-01-01

The results of seven years of operation of the Spanish Network for Isotopes ( 2 H, 1 8O y 3 H) in Precipitation (REVIP) are shown. this Network is managed since 2000 by the Centro de Estudios de Tecnicas Aplicadas of the Centro de Estudios y Experimentacion de Obras Publicas (CEDEX) in collaboration with the Agencia Estatal de Meteorologia (AEMET). The results of REVIP are sent to the International Atomic Energy Agency (IAEA) in order to be integrated in the Global Network for Isotopes in Precipitation (GNIP). The spatial distribution of stable isotopes ( 1 8O h 2 H) in precipitation in Spain follows a multiple regression model, based on two geographic factors: latitude and elevation, which is strongly correlated with temperature, an important factor controlling isotope fractionation. This information on 1 8O and 2 H is useful to trace surface and ground waters and, combined with the information, about the spatial and temporal distribution of the Tritium ( 3 H) concentration in precipitation, allows to date these waters in order to estimate flow directions and velocities, and to evaluate the residence time of water resources and aquifer vulnerability. (Author)

Natural isotope technique for the exploration and exploitation of ground water

International Nuclear Information System (INIS)

Zainal Abidin; Hudi Hastowo; Aang Hanafiah

2007-01-01

In line with the condition of climate and hydrology, Indonesia has a fast amount of aquifers which are sources of ground water. In several areas large number of springs occurred with small to large debits which is a sign of ground water potential. Ground water is a potential reservoir to be use at maximum for several purposes such as drinking water, industry and tourism. Large cities such as Jakarta, Bandung and others depend on ground water for their industries and hotels. The exploitation of ground water use has to be controlled and monitoring of a management system have to be done. Research carried out only on the exploitation of geophysics and hydrology showed that the amount of ground water reservoirs is not enough to be used when it comes to justification to explore it. Other parameters are still be needed which are the origins and dating of the ground water, these last two factors mentioned have to be taken into consideration in the system of conversion and balance of water. An alternative technology to determine the two factors mentioned in a short time is the natural isotope technique of 18 O, 2 H and 14 C. This technique is used to determine the origin of water, and isotope 14 C is carried out to determine the age of ground water. Isotopes 18 H and 2 H are stable isotopes in the form of water and is integrated in the hydrological cycle. Their specific concentrations in rain water at several elevations are used as fingerprints to locate the area of ground water supplement and its origin. Isotope 14 C is a natural radioactive isotope with a half-life of 5.730 years and is found in the hydrology cycle and enters the ground water system through CO 2 gas which is dissolved in water. 14 C isotope could determine the age of ground water and is also able to indicate the potential/amount of ground water. Studies of exploration and exploration monitoring of ground water should be an integrated study by geohydrology, geophysics and isotope and could be a solution of

Pollinators, pests, and predators: Recognizing ecological trade-offs in agroecosystems.

Science.gov (United States)

Saunders, Manu E; Peisley, Rebecca K; Rader, Romina; Luck, Gary W

2016-02-01

Ecological interactions between crops and wild animals frequently result in increases or declines in crop yield. Yet, positive and negative interactions have mostly been treated independently, owing partly to disciplinary silos in ecological and agricultural sciences. We advocate a new integrated research paradigm that explicitly recognizes cost-benefit trade-offs among animal activities and acknowledges that these activities occur within social-ecological contexts. Support for this paradigm is presented in an evidence-based conceptual model structured around five evidence statements highlighting emerging trends applicable to sustainable agriculture. The full range of benefits and costs associated with animal activities in agroecosystems cannot be quantified by focusing on single species groups, crops, or systems. Management of productive agroecosystems should sustain cycles of ecological interactions between crops and wild animals, not isolate these cycles from the system. Advancing this paradigm will therefore require integrated studies that determine net returns of animal activity in agroecosystems.

Isotope effect and deuterium excess parameter revolution in ice and snow melt

International Nuclear Information System (INIS)

Yin Guan; Ni Shijun; Fan Xiao; Wu Hao

2003-01-01

The change of water isotope composition actually is a integrated reaction depending on the change of environment. The ice and snow melt of different seasons in high mountain can obviously influence the change of isotope composition and deuterium excess parameter of surface flow and shallow groundwater. To know the isotopic fractionation caused by this special natural background, explore its forming and evolvement, is unusually important for estimating, the relationship between the environment, climate and water resources in an area. Taking the example of isotope composition of surface flow and shallow groundwater in Daocheng, Sichuan, this paper mainly introduced the changing law of isotope composition and deuterium excess parameter of surface flow and hot-spring on conditions of ice and snow melt with different seasons in high mountain; emphatically discussed the isotope effect and deuterium excess parameter revolution in the process of ice and snow melting and its reason. (authors)

Integral statistical eco-indices - effective complementary tool for assessment of ecological state of and ecological risks for water ecosystems

International Nuclear Information System (INIS)

Bashamkova, I

2010-01-01

Eco-indices are successfully used for assessment of the ecological state and risks of water reservoirs. They allow, already at early stages, to detect negative effects on water ecosystems caused by progressive anthropogenic impacts and widening of the spectrum of pollutants, and to quantitatively evaluate ecological risks and damage for water reservoirs. Implementing these modern tools to water quality assessment is one of the lines to make decisions concerning challenging environmental problems.

[Simulation of urban ecological security pattern based on cellular automata: a case of Dongguan City, Guangdong Province of South China].

Science.gov (United States)

Yang, Qing-Sheng; Qiao, Ji-Gang; Ai, Bin

2013-09-01

Taking the Dongguan City with rapid urbanization as a case, and selecting landscape ecological security level as evaluation criterion, the urbanization cellular number of 1 km x 1 km ecological security cells was obtained, and imbedded into the transition rules of cellular automata (CA) as the restraint term to control urban development, establish ecological security urban CA, and simulate ecological security urban development pattern. The results showed the integrated landscape ecological security index of the City decreased from 0.497 in 1998 to 0.395 in 2005, indicating that the ecological security at landscape scale was decreased. The CA-simulated integrated ecological security index of the City in 2005 was increased from the measured 0.395 to 0.479, showing that the simulated urban landscape ecological pressure from human became lesser, ecological security became better, and integrated landscape ecological security became higher. CA could be used as an effective tool in researching urban ecological security.

Validation of the doubly labeled water method using off-axis integrated cavity output spectroscopy and isotope ratio mass spectrometry.

Science.gov (United States)

Melanson, Edward L; Swibas, Tracy; Kohrt, Wendy M; Catenacci, Vicki A; Creasy, Seth A; Plasqui, Guy; Wouters, Loek; Speakman, John R; Berman, Elena S F

2018-02-01

When the doubly labeled water (DLW) method is used to measure total daily energy expenditure (TDEE), isotope measurements are typically performed using isotope ratio mass spectrometry (IRMS). New technologies, such as off-axis integrated cavity output spectroscopy (OA-ICOS) provide comparable isotopic measurements of standard waters and human urine samples, but the accuracy of carbon dioxide production (V̇co 2 ) determined with OA-ICOS has not been demonstrated. We compared simultaneous measurement V̇co 2 obtained using whole-room indirect calorimetry (IC) with DLW-based measurements from IRMS and OA-ICOS. Seventeen subjects (10 female; 22 to 63 yr) were studied for 7 consecutive days in the IC. Subjects consumed a dose of 0.25 g H 2 18 O (98% APE) and 0.14 g 2 H 2 O (99.8% APE) per kilogram of total body water, and urine samples were obtained on days 1 and 8 to measure average daily V̇co 2 using OA-ICOS and IRMS. V̇co 2 was calculated using both the plateau and intercept methods. There were no differences in V̇co 2 measured by OA-ICOS or IRMS compared with IC when the plateau method was used. When the intercept method was used, V̇co 2 using OA-ICOS did not differ from IC, but V̇co 2 measured using IRMS was significantly lower than IC. Accuracy (~1-5%), precision (~8%), intraclass correlation coefficients ( R = 0.87-90), and root mean squared error (30-40 liters/day) of V̇co 2 measured by OA-ICOS and IRMS were similar. Both OA-ICOS and IRMS produced measurements of V̇co 2 with comparable accuracy and precision compared with IC.

Evaluation of HFIR [High Flux Isotope Reactor] pressure-vessel integrity considering radiation embrittlement

International Nuclear Information System (INIS)

Cheverton, R.D.; Merkle, J.G.; Nanstad, R.K.

1988-04-01

The High Flux Isotope Reactor (HFIR) pressure vessel has been in service for 20 years, and during this time, radiation damage was monitored with a vessel-material surveillance program. In mid-November 1986, data from this program indicated that the radiation-induced reduction in fracture toughness was greater than expected. As a result, a reevaluation of vessel integrity was undertaken. Updated methods of fracture-mechanics analysis were applied, and an accelerated irradiations program was conducted using the Oak Ridge Research Reactor. Results of these efforts indicate that (1) the vessel life can be extended 10 years if the reactor power level is reduced 15% and if the vessel is subjected to a hydrostatic proof test each year; (2) during the 10-year life extension, significant radiation damage will be limited to a rather small area around the beam tubes; and (3) the greater-than-expected damage rate is the result of the very low neutron flux in the HFIR vessel relative to that in samples of material irradiated in materials-testing reactors (a factor of ∼10 4 less), that is, a rate effect

Formation of ecological and legal science: resource aspect and its integration problems

Directory of Open Access Journals (Sweden)

А. П. Гетьман

2016-04-01

debate and controversy as a confirmation of their own conclusions about the artificial synthesized nature of environmental law, artificiality of scientific problems and so on. One of the ways to integrate and harmonize the natural resource component within the environmental law is to change its focus from solely having binding traditional natural objects in favor of a more progressive and promising theory of the resource or the ecological and resource rights that can harmoniously incorporate both traditional (established, and innovative approaches to the maintenance of ecological and legal relations, their expansion and diffusion within a single methodological approach and legal doctrine, which is the fundamental goal of ecological and legal science, defined as the environment, the use of environmental resources and ecological security of humanity.

Stable isotope fingerprinting: a novel method for identifying plant, fungal, or bacterial origins of amino acids

Science.gov (United States)

Thomas Larsen; D. Lee Taylor; Mary Beth Leigh; Diane M. O' Brien

2009-01-01

Amino acids play an important role in ecology as essential nutrients for animals and as currencies in symbiotic associations. Here we present a new approach to tracing the origins of amino acids by identifying unique patterns of carbon isotope signatures generated by amino acid synthesis in plants, fungi, and bacteria ("13C fingerprints...

Behavior Analysis and Ecological Psychology: Past, Present, and Future. A Review of Harry Heft's Ecological Psychology in Context

Science.gov (United States)

Morris, Edward K

2009-01-01

Relations between behavior analysis and ecological psychology have been strained for years, notwithstanding the occasional comment on their affinities. Harry Heft's (2001) Ecological Psychology in Context provides an occasion for reviewing anew those relations and affinities. It describes the genesis of ecological psychology in James's radical empiricism; addresses Holt's neorealism and Gestalt psychology; and synthesizes Gibson's ecological psychology and Barker's ecobehavioral science as a means for understanding everyday human behavior. Although behavior analysis is excluded from this account, Heft's book warrants a review nonetheless: It describes ecological psychology in ways that are congruent and complementary with behavior analysis (e.g., nonmediational theorizing; the provinces of natural history and natural science). After introducing modern ecological psychology, I comment on (a) Heft's admirable, albeit selective, historiography; (b) his ecological psychology—past and present—as it relates to Skinner's science and system (e.g., affordances, molar behavior); (c) his misunderstandings of Skinner's behaviorism (e.g., reductionistic, mechanistic, molecular); and (d) the theoretical status of Heft's cognitive terms and talk (i.e., in ontology, epistemology, syntax). I conclude by considering the alliance and integration of ecological psychology and behavior analysis, and their implications for unifying and transforming psychology as a life science, albeit more for the future than at present. PMID:20354604

Calculation of isotopic mass and energy production by a matrix operator method

International Nuclear Information System (INIS)

Lee, C.E.

1976-08-01

The Volterra method of the multiplicative integral is used to determine the isotopic density, mass, and energy production in linear systems. The solution method, assumptions, and limitations are discussed. The method allows a rapid accurate calculation of the change in isotopic density, mass, and energy production independent of the magnitude of the time steps, production or decay rates, or flux levels

Isotope Ratio Monitoring Gas Chromatography Mass Spectrometry (IRM-GCMS)

International Nuclear Information System (INIS)

Freeman, K.H.; Ricci, S.A.; Studley, A.; Hayes, J.M.

1989-01-01

On Earth, the C-13 content of organic compounds is depleted by roughly 13 to 23 permil from atmospheric carbon dioxide. This difference is largely due to isotope effects associated with the fixation of inorganic carbon by photosynthetic organisms. If life once existed on Mars, then it is reasonable to expect to observe a similar fractionation. Although the strongly oxidizing conditions on the surface of Mars make preservation of ancient organic material unlikely, carbon-isotope evidence for the existence of life on Mars may still be preserved. Carbon depleted in C-13 could be preserved either in organic compounds within buried sediments, or in carbonate minerals produced by the oxidation of organic material. A technique is introduced for rapid and precise measurement of the C-13 contents of individual organic compounds. A gas chromatograph is coupled to an isotope-ratio mass spectrometer through a combustion interface, enabling on-line isotopic analysis of isolated compounds. The isotope ratios are determined by integration of ion currents over the course of each chromatographic peak. Software incorporates automatic peak determination, corrections for background, and deconvolution of overlapped peaks. Overall performance of the instrument was evaluated by the analysis of a mixture of high purity n-alkanes of know isotopic composition. Isotopic values measured via IRM-GCMS averaged withing 0.55 permil of their conventionally measured values

An approach to grouping species for ecological risk assessment

International Nuclear Information System (INIS)

Hampton, N.L.; VanHorn, R.L.; Morris, R.; Brewer, R.

1994-01-01

The ecological risk assessment (ERA) paradigm acknowledges all levels of ecological organization as having potential for defining assessment and measurement endpoints. However, assessment goals and endpoints are generally concentrated at individual species and population levels. As part of a sitewide, screening-level ERA process at the Idaho National Engineering Laboratory (INEL), a ''functional group'' approach was developed to incorporate assessment at a higher level of ecological organization into the risk analysis process. Functional groups demonstrating biological similarity and similar potential for contaminant exposure were developed using taxonomic, trophic and habitat parameters. As defined, all species are potential surrogates for the other members of the same functional group. Measurement endpoint data for several species may be integrated to address the risk to the group as a whole. The functional group concept was applied throughout the problem formulation, analysis, and risk characterization phases of the assessment process. This approach allows the ERA to be focused on risk to the integrity of individual functional groups, which can subsequently be related to guild and community integrity

Community ecology in a changing environment: Perspectives from the Quaternary.

Science.gov (United States)

Jackson, Stephen T; Blois, Jessica L

2015-04-21

Community ecology and paleoecology are both concerned with the composition and structure of biotic assemblages but are largely disconnected. Community ecology focuses on existing species assemblages and recently has begun to integrate history (phylogeny and continental or intercontinental dispersal) to constrain community processes. This division has left a "missing middle": Ecological and environmental processes occurring on timescales from decades to millennia are not yet fully incorporated into community ecology. Quaternary paleoecology has a wealth of data documenting ecological dynamics at these timescales, and both fields can benefit from greater interaction and articulation. We discuss ecological insights revealed by Quaternary terrestrial records, suggest foundations for bridging between the disciplines, and identify topics where the disciplines can engage to mutual benefit.

The skin microbiome: impact of modern environments on skin ecology, barrier integrity, and systemic immune programming.

Science.gov (United States)

Prescott, Susan L; Larcombe, Danica-Lea; Logan, Alan C; West, Christina; Burks, Wesley; Caraballo, Luis; Levin, Michael; Etten, Eddie Van; Horwitz, Pierre; Kozyrskyj, Anita; Campbell, Dianne E

2017-01-01

Skin barrier structure and function is essential to human health. Hitherto unrecognized functions of epidermal keratinocytes show that the skin plays an important role in adapting whole-body physiology to changing environments, including the capacity to produce a wide variety of hormones, neurotransmitters and cytokine that can potentially influence whole-body states, and quite possibly, even emotions. Skin microbiota play an integral role in the maturation and homeostatic regulation of keratinocytes and host immune networks with systemic implications. As our primary interface with the external environment, the biodiversity of skin habitats is heavily influenced by the biodiversity of the ecosystems in which we reside. Thus, factors which alter the establishment and health of the skin microbiome have the potential to predispose to not only cutaneous disease, but also other inflammatory non-communicable diseases (NCDs). Indeed, disturbances of the stratum corneum have been noted in allergic diseases (eczema and food allergy), psoriasis, rosacea, acne vulgaris and with the skin aging process. The built environment, global biodiversity losses and declining nature relatedness are contributing to erosion of diversity at a micro-ecological level, including our own microbial habitats. This emphasises the importance of ecological perspectives in overcoming the factors that drive dysbiosis and the risk of inflammatory diseases across the life course.

Novel catalysts for isotopic exchange between hydrogen and liquid water

International Nuclear Information System (INIS)

Butler, J.P.; Rolston, J.H.; Stevens, W.H.

1978-01-01

Catalytic isotopic exchange between hydrogen and liquid water offers many inherent potential advantages for the separation of hydrogen isotopes which is of great importance in the Canadian nuclear program. Active catalysts for isotopic exchange between hydrogen and water vapor have long been available, but these catalysts are essentially inactive in the presence of liquid water. New, water-repellent platinum catalysts have been prepared by: (1) treating supported catalysts with silicone, (2) depositing platinum on inherently hydrophobic polymeric supports, and (3) treating platinized carbon with Teflon and bonding to a carrier. The activity of these catalysts for isotopic exchange between countercurrent streams of liquid water and hydrogen saturated with water vapor has been measured in a packed trickle bed integral reactor. The performance of these hydrophobic catalysts is compared with nonwetproofed catalysts. The mechanism of the overall exchange reaction is briefly discussed. 6 figures

Application of the isotopic index in isotope geochemical investigation

International Nuclear Information System (INIS)

Schuetze, H.

1982-06-01

A method is described which allows to calculate approximately isotope exchange equilibria between different crystalline silicates. The algorithm uses a newly introduced isotopic index. It is defined using isotopic increments of the variant types of silicatic bonds. This isotopic index gives a quantitative measure of the ability to enrich 18 O or 30 Si, respectively. The dependence of isotopic fractionations on temperature can be calculated approximately by means of the isotopic index, too. On this theoretical base some problems of magmatism and two varieties of an isotope geochemical model of the evolution of the Earth's crust are treated. Finally, the possibility is demonstrated to give prognostic statements about the likelihood of ore bearing of different granites. (author)

Odonata (dragonflies and damselflies) as a bridge between ecology and evolutionary genomics.

Science.gov (United States)

Bybee, Seth; Córdoba-Aguilar, Alex; Duryea, M Catherine; Futahashi, Ryo; Hansson, Bengt; Lorenzo-Carballa, M Olalla; Schilder, Ruud; Stoks, Robby; Suvorov, Anton; Svensson, Erik I; Swaegers, Janne; Takahashi, Yuma; Watts, Phillip C; Wellenreuther, Maren

2016-01-01

Odonata (dragonflies and damselflies) present an unparalleled insect model to integrate evolutionary genomics with ecology for the study of insect evolution. Key features of Odonata include their ancient phylogenetic position, extensive phenotypic and ecological diversity, several unique evolutionary innovations, ease of study in the wild and usefulness as bioindicators for freshwater ecosystems worldwide. In this review, we synthesize studies on the evolution, ecology and physiology of odonates, highlighting those areas where the integration of ecology with genomics would yield significant insights into the evolutionary processes that would not be gained easily by working on other animal groups. We argue that the unique features of this group combined with their complex life cycle, flight behaviour, diversity in ecological niches and their sensitivity to anthropogenic change make odonates a promising and fruitful taxon for genomics focused research. Future areas of research that deserve increased attention are also briefly outlined.

The isotopic contamination in electromagnetic isotope separators; La contagion isotopique dans les separateurs electromagnetiques d'isotopes

Energy Technology Data Exchange (ETDEWEB)

Cassignol, Ch [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

In the early years of isotope separation, and in particular electromagnetic isotope separation, needs for rapid results have conducted to empiric research. This paper describes fundamental research on the electromagnetic isotope separation to a better understanding of isotope separators as well as improving the performances. Focus has been made on the study of the principle of isotope contamination and the remedial action on the separator to improve the isotope separation ratio. In a first part, the author come back to the functioning of an electromagnetic separator and generalities on isotope contamination. Secondly, it describes the two stages separation method with two dispersive apparatus, an electromagnetic separation stage followed by an electrostatic separation stage, both separated by a diaphragm. The specifications of the electrostatic stage are given and its different settings and their consequences on isotope separation are investigated. In a third part, mechanisms and contamination factors in the isotope separation are discussed: natural isotope contamination, contamination by rebounding on the collector, contamination because of a low resolution, contamination by chromatism and diffusion effect, breakdown of condenser voltage. Analysis of experimental results shows the diffusion as the most important contamination factor in electromagnetic isotope separation. As contamination factors are dependent on geometric parameters, sector angle, radius of curvature in the magnetic field and clearance height are discussed in a fourth part. The better understanding of the mechanism of the different contamination factors and the study of influential parameters as pressure and geometric parameters lead to define a global scheme of isotope contamination and determinate optima separator design and experimental parameters. Finally, the global scheme of isotope contamination and hypothesis on optima specifications and experimental parameters has been checked during a

Countermeasures for China’s Ecological Environment Construction in Land Reclamation

Institute of Scientific and Technical Information of China (English)

Chen; LI; Xinfeng; LIU; Zhe; PENG; Tao; SI; Lingfeng; KONG

2013-01-01

Basic situation of the current ecological environment construction in land consolidation and rehabilitation of China is introduced. The related advanced experience abroad is summarized from mainly four aspects, namely policy, system as well as subject development, planning guidance, design method of project planning and engineering study, and practical countermeasures to China’s ecological environment construction in land reclamation are proposed. In terms of policy, system and subject, relevant regulations, policies and system construction should be strengthened and the framework of policy, system and subject development in ecological landscape construction of China’s land reclamation should be proposed, integrating ecological environment construction into land reclamation. At the level of strategic planning, the spatial layout and construction key points of green infrastructure in land reclamation of "urban multi-functional developing region, eastern economic developed region, central modern agricultural region and northwestern ecological fragile region" should be achieved. At the level of project planning design, ecological principles, sustainable landscape design principles and vernacular landscape design methods are to be integrated into the planning procedure to form operable technique regulations or introductions. At the level of engineering design, engineering technique system, standards and regulations of ditches, roads, forests and channels with local distinctions should be formulated according to the characters and strategic demands of urbanization, industrialization, agriculture modernization and ecological environment preservation in different regions.

Reconstruction of fire regimes through integrated paleoecological proxy data and ecological modeling.

Science.gov (United States)

Iglesias, Virginia; Yospin, Gabriel I; Whitlock, Cathy

2014-01-01

Fire is a key ecological process affecting vegetation dynamics and land cover. The characteristic frequency, size, and intensity of fire are driven by interactions between top-down climate-driven and bottom-up fuel-related processes. Disentangling climatic from non-climatic drivers of past fire regimes is a grand challenge in Earth systems science, and a topic where both paleoecology and ecological modeling have made substantial contributions. In this manuscript, we (1) review the use of sedimentary charcoal as a fire proxy and the methods used in charcoal-based fire history reconstructions; (2) identify existing techniques for paleoecological modeling; and (3) evaluate opportunities for coupling of paleoecological and ecological modeling approaches to better understand the causes and consequences of past, present, and future fire activity.

Isotopically modified compounds

International Nuclear Information System (INIS)

Kuruc, J.

2009-01-01

In this chapter the nomenclature of isotopically modified compounds in Slovak language is described. This chapter consists of following parts: (1) Isotopically substituted compounds; (2) Specifically isotopically labelled compounds; (3) Selectively isotopically labelled compounds; (4) Non-selectively isotopically labelled compounds; (5) Isotopically deficient compounds.

Interdisciplinary Industrial Ecology Education: Recommendations for an Inclusive Pedagogical Model

Science.gov (United States)

Sharma, Archana

2009-01-01

Industrial ecology education is being developed and delivered predominantly within the domains of engineering and management. Such an approach could prove somewhat limiting to the broader goal of developing industrial ecology as an integrated knowledge base inclusive of diverse disciplines, contributing to sustainable development. This paper…

Ecological stability of landscape - ecological infrastructure - ecological management

International Nuclear Information System (INIS)

1992-01-01

The Field Workshop 'Ecological Stability of Landscape - Ecological Infrastructure - Ecological Management' was held within a State Environmental Programme financed by the Federal Committee for the Environment. The objectives of the workshop were to present Czech and Slovak approaches to the ecological stability of the landscape by means of examples of some case studies in the field, and to exchange ideas, theoretical knowledge and practical experience on implementing the concept of ecological infrastructure in landscape management. Out of 19 papers contained in the proceedings, 3 items were inputted to the INIS system. (Z.S.)

Isotope effect and isotope separation. A chemist's view

International Nuclear Information System (INIS)

Ishida, Takanobu

2002-01-01

What causes the isotope effects (IE)? This presentation will be centered around the equilibrium isotope effects due to the differences in the nuclear masses. The occurrence of the equilibrium constant, K, of isotope exchange reactions which differ from the values predicted by the classical theory of statistical mechanics, K cl , is explored. The non-classical K corresponds to the unit-stage separation factor, α, that is different from unity and forms a basis of an isotope separation process involving the chemical exchange reaction. Here, the word 'chemical exchange' includes not only the isotope exchange chemical reactions between two or more chemical species but also the isotope exchanges involving the equilibria between liquid and vapor phases and liquid-gas, liquid solution-gas, liquid-liquid, and solid-liquid phases. In Section I, origins of the isotope effect phenomena will be explored and, in the process, various quantities used in discussions of isotope effect that have often caused confusions will be unambiguously defined. This Section will also correlate equilibrium constant with separation factor. In Section II, various forms of temperature-dependence of IE and separation factor will be discussed. (author)

Mercury Stable Isotopes Discriminate Different Populations of European Seabass and Trace Potential Hg Sources around Europe.

Science.gov (United States)

Cransveld, Alice; Amouroux, David; Tessier, Emmanuel; Koutrakis, Emmanuil; Ozturk, Ayaka A; Bettoso, Nicola; Mieiro, Cláudia L; Bérail, Sylvain; Barre, Julien P G; Sturaro, Nicolas; Schnitzler, Joseph; Das, Krishna

2017-11-07

Our study reports the first data on mercury (Hg) isotope composition in marine European fish, for seven distinct populations of the European seabass, Dicentrarchus labrax. The use of δ 202 Hg and Δ 199 Hg values in SIBER enabled us to estimate Hg isotopic niches, successfully discriminating several populations. Recursive-partitioning analyses demonstrated the relevance of Hg stable isotopes as discriminating tools. Hg isotopic values also provided insight on Hg contamination sources for biota in coastal environment. The overall narrow range of δ 202 Hg around Europe was suggested to be related to a global atmospheric contamination while δ 202 Hg at some sites was linked either to background contamination, or with local contamination sources. Δ 199 Hg was related to Hg levels of fish but we also suggest a relation with ecological conditions. Throughout this study, results from the Black Sea population stood out, displaying a Hg cycling similar to fresh water lakes. Our findings bring out the possibility to use Hg isotopes in order to discriminate distinct populations, to explore the Hg cycle on a large scale (Europe) and to distinguish sites contaminated by global versus local Hg source. The interest of using Hg sable isotopes to investigate the whole European Hg cycle is clearly highlighted.

Savannah River Ecology Laboratory. Annual technical progress report of ecological research

International Nuclear Information System (INIS)

Smith, M.H.

1996-01-01

The Savannah River Ecology Laboratory (SREL) is a research unit of the University of Georgia (UGA). The overall mission of the Laboratory is to acquire and communicate knowledge of ecological processes and principles. SREL conducts basic and applied ecological research, as well as education and outreach programs, under a contract with the U.S. Department of Energy (DOE) at the Savannah River Site (SRS) near Aiken, South Carolina. Significant accomplishments were made during the past year in the areas of research, education and service. The Laboratory's research mission was fulfilled with the publication of two books and 143 journal articles and book chapters by faculty, technical and students, and visiting scientists. An additional three books and about 80 journal articles currently are in press. Faculty, technician and students presented 193 lectures, scientific presentations, and posters to colleges and universities, including minority institutions. Dr. J Vaun McArthur organized and conducted the Third Annual SREL Symposium on the Environment: New Concepts in Strewn Ecology: An Integrative Approach. Dr. Michael Newman conducted a 5-day course titled Quantitative Methods in Ecotoxicology, and Dr. Brian Teppen of The Advanced Analytical Center for Environmental Sciences (AACES) taught a 3-day short course titled Introduction to Molecular Modeling of Environmental Systems. Dr. I. Lehr Brisbin co-hosted a meeting of the Crocodile Special Interest Group. Dr. Rebecca Sharitz attended four symposia in Japan during May and June 1996 and conducted meetings of the Executive Committee and Board of the International Association for Ecology (ENTECOL)

Savannah River Ecology Laboratory. Annual technical progress report of ecological research

Energy Technology Data Exchange (ETDEWEB)

Smith, M.H.

1996-07-31

The Savannah River Ecology Laboratory (SREL) is a research unit of the University of Georgia (UGA). The overall mission of the Laboratory is to acquire and communicate knowledge of ecological processes and principles. SREL conducts basic and applied ecological research, as well as education and outreach programs, under a contract with the U.S. Department of Energy (DOE) at the Savannah River Site (SRS) near Aiken, South Carolina. Significant accomplishments were made during the past year in the areas of research, education and service. The Laboratory`s research mission was fulfilled with the publication of two books and 143 journal articles and book chapters by faculty, technical and students, and visiting scientists. An additional three books and about 80 journal articles currently are in press. Faculty, technician and students presented 193 lectures, scientific presentations, and posters to colleges and universities, including minority institutions. Dr. J Vaun McArthur organized and conducted the Third Annual SREL Symposium on the Environment: New Concepts in Strewn Ecology: An Integrative Approach. Dr. Michael Newman conducted a 5-day course titled Quantitative Methods in Ecotoxicology, and Dr. Brian Teppen of The Advanced Analytical Center for Environmental Sciences (AACES) taught a 3-day short course titled Introduction to Molecular Modeling of Environmental Systems. Dr. I. Lehr Brisbin co-hosted a meeting of the Crocodile Special Interest Group. Dr. Rebecca Sharitz attended four symposia in Japan during May and June 1996 and conducted meetings of the Executive Committee and Board of the International Association for Ecology (ENTECOL).

Introduction to the Special Issue: Beyond traits: integrating behaviour into plant ecology and biology.

Science.gov (United States)

Cahill, James F

2015-10-26

The way that plants are conceptualized in the context of ecological understanding is changing. In one direction, a reductionist school is pulling plants apart into a list of measured 'traits', from which ecological function and outcomes of species interactions may be inferred. This special issue offers an alternative, and more holistic, view: that the ecological functions performed by a plant will be a consequence not only of their complement of traits but also of the ways in which their component parts are used in response to environmental and social conditions. This is the realm of behavioural ecology, a field that has greatly advanced our understanding of animal biology, ecology and evolution. Included in this special issue are 10 articles focussing not on the tried and true metaphor that plant growth is similar to animal movement, but instead on how application of principles from animal behaviour can improve our ability to understand plant biology and ecology. The goals are not to draw false parallels, nor to anthropomorphize plant biology, but instead to demonstrate how existing and robust theory based on fundamental principles can provide novel understanding for plants. Key to this approach is the recognition that behaviour and intelligence are not the same. Many organisms display complex behaviours despite a lack of cognition (as it is traditionally understood) or any hint of a nervous system. The applicability of behavioural concepts to plants is further enhanced with the realization that all organisms face the same harsh forces of natural selection in the context of finding resources, mates and coping with neighbours. As these ecological realities are often highly variable in space and time, it is not surprising that all organisms-even plants-exhibit complex behaviours to handle this variability. The articles included here address diverse topics in behavioural ecology, as applied to plants: general conceptual understanding, plant nutrient foraging, root

Lifetime Stable isotopes profiles in whale earplug: assessment of foraging and migrations in the Northern Hemisphere

Science.gov (United States)

Mansouri, F.; Crain, D.; Winfield, Z.; Trumble, S.; Usenko, S.

2017-12-01

Whale earplugs, historically used for aging, were used to reconstruct lifetime stable isotope profiles for carbon (δ13C) and nitrogen (δ15N) for individual whales by delaminating lamina within the earplug. These stable isotope profile, which provide Continuous lifetime records of feeding, foraging ecology, and migration, were determined for 20 individuals from 4 baleen species including fin, minke, humpback, and blue whales spanning more than a century (1869 - 2014) using stable isotope analysis. Approximately 1 mg tissue from each lamina (n=1200) was analyzed for carbon and nitrogen stable isotope using continuous flow isotope ratio mass spectrometer (CF-IRMS). This research using whale earplugs have combined age estimates with stable isotope measurements to reconstruct lifetime foraging profiles with a 6-month resolution, providing an unprecedented opportunity to assess periods and trends in dietary fluctuations as well as migration between different foraging area which have distinct isotope values. Trends with these profiles suggest long-term changing in migration, while annual variability highlights seasonal fasting and feeding. Isotopic ratios were also used to identify subpopulations of Atlantic fin whales, which enabled us to assign unidentified humpback and minke whales to the Atlantic or Pacific Oceans. This historical archive of data provides us an unprecedented tool to assess long term marine ecosystem and subsequently marine organism transition to alternate foraging area and shed light on the whale's population status in the Northern hemisphere.

Trophic ecology of deep-sea Asteroidea (Echinodermata) from eastern Canada

Science.gov (United States)

Gale, Katie S. P.; Hamel, Jean-François; Mercier, Annie

2013-10-01

Asteroids (sea stars) can be important predators in benthic communities and are often present in ecologically important and vulnerable deep-sea coral and sponge habitats. However, explicit studies on the trophic ecology of deep-sea asteroids are rare. We investigated the diets of seven species of deep-sea asteroid from the bathyal zone of Newfoundland and Labrador, eastern Canada. A multifaceted approach including live animal observations, stomach content analysis, and stable isotope analysis revealed the asteroids to be either top predators of megafauna or secondary consumers (mud ingesters, infaunal predators, and suspension feeders). The stable isotope signatures of Ceramaster granularis, Hippasteria phrygiana, and Mediaster bairdi are characteristic of high-level predators, having δ15N values 4.4‰ (more than one trophic level) above Ctenodiscus crispatus, Leptychaster arcticus, Novodinia americana, and Zoroaster fulgens. We present strong evidence that corals and sponges are common food items for two of the predatory species, C. granularis and H. phrygiana. During laboratory feeding trials, live H. phrygiana fed on several species of soft coral and C. granularis fed on sponges. Stomach content analysis of wild-caught individuals revealed sclerites from sea pens (e.g. Pennatula sp.) in the stomachs of both asteroid species; H. phrygiana also contained sclerites from at least two other species of octocoral and siliceous sponge spicules were present in the stomachs of C. granularis. The stomach contents of the secondary consumers contained a range of invertebrate material. Leptychaster arcticus and Ctenodiscus crispatus feed infaunally on bulk sediment and molluscs, Zoroaster fulgens is a generalist infaunal predator, and the brisingid Novodinia americana is a specialist suspension feeder on benthopelagic crustaceans. This study provides a foundation for understanding the ecological roles of bathyal asteroids, and suggests that some species may have the

The isotope density inverse problem in multigroup neutron transport

International Nuclear Information System (INIS)

Zazula, J.M.

1981-01-01

The inverse problem for stationary multigroup anisotropic neutron transport is discussed in order to search for isotope densities in multielement medium. The spatial- and angular-integrated form of neutron transport equation, in terms of the flux in a group - density of an element spatial correlation, leads to a set of integral functionals for the densities weighted by the group fluxes. Some methods of approximation to make the problem uniquently solvable are proposed. Particularly P 0 angular flux information and the spherically-symetrical geometry of an infinite medium are considered. The numerical calculation using this method related to sooner evaluated direct problem data gives promising agreement with primary densities. This approach would be the basis for further application in an elemental analysis of a medium, using an isotopic neutron source and a moving, energy-dependent neutron detector. (author)

Ancient ecology of 15-million-year-old browsing mammals within C3 plant communities from Panama.

Science.gov (United States)

MacFadden, Bruce J; Higgins, Pennilyn

2004-06-01

Middle Miocene mammals are known from approximately 15 million-year-old sediments exposed along the Panama Canal of Central America, a region that otherwise has an exceedingly poor terrestrial fossil record. These land mammals, which represent a part of the ancient terrestrial herbivore community, include an oreodont Merycochoerus matthewi, small camel-like protoceratid artiodactyl Paratoceras wardi, two horses Anchitherium clarencei and Archaeohippus sp., and two rhinos Menoceras barbouri and Floridaceras whitei. Bulk and serial carbon and oxygen isotope analyses of the tooth enamel carbonate allow reconstruction of the ancient climate and ecology of these fossil mammals. Ancient Panama had an equable climate with seasonal temperature and rainfall fluctuations less than those seen today. The middle Miocene terrestrial community consisted predominantly, or exclusively, of C3 plants, i.e., there is no evidence for C4 grasses. Statistically different mean carbon isotope values for the mammalian herbivores indicate niche partitioning of the C3 plant food resources. The range of individual carbon isotope analyses, i.e., delta13C from -15.9 to -10.1 per thousand, indicates herbivores feeding on diverse plants from different habitats with extrapolated delta13C values of -29.9 to -24.2 per thousand, possibly ranging from dense forest to more open country woodland. The ecological niches of individual mammalian herbivore species were differentiated either by diet or body size.

The significance of the Danube ecological corridor in the proceedings of implementing ecological networks in Serbia

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Filipović Dejan

2015-01-01

Full Text Available With the modern processes for exploiting land people have altered the original appearance of areas and created cultural environments. The remaining natural environments, whether protected or not, take up a relatively small portion of space and represent isolated islands which in itself can not be sufficient for the preservation of biodiversity or for the fulfillment of national, regional or international goals and commitments related to their preservation. In order to secure the preservation of biodiversity, the strengthening of integrity and the natural processes, such as animal migrations, succession of vegetation and evolution processes, the communication between natural habitats is imperative. Ecological corridors, as integral elements of ecological networks, ensure the preservation of vital ecological interactions by providing a connection between different habitats or areas. Depending on a range of factors, from the fulfillment of demands of different species to the connecting of regions, corridors of local, sub-regional, regional and international importance are identified. The Danube ecological corridor is one of the most significant corridors of international importance which encompasses a large number of habitats which are part of the natural watercourse of the corridor. There are numerous protected areas in the Danube coastal area on Serbia's territory which present themselves as central areas for forming the ecological network, such as: Gornje Podunavlje, Karađorđevo, Fruška Gora, Titelski Breg hill, Kovalski rit marsh, Dunavski loess bluffs, the Sava mouth, Labudovo okno, Deliblato sands, Đerdap and Mala Vrbica. The diverse and mosaic vegetation of the floodplain, as well as the consistency of the protected areas within the Danube corridor have a direct influence on the quality and functionality of this corridor. The goal of this paper is to show the significance of the Danube ecological corridor in the process of implementing

Proceedings of the study of environmental change using isotope techniques

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-10-01

Global warming is acknowledged as a major crisis facing society today, principally due to anticipated impacts on the environment, and availability and distribution of water resources. Scientific understanding of recent human-induced climate change, as well as evaluation of potential mitigation strategies, is progressively being developed through studies of atmospheric greenhouse gases and modern water energy carbon cycling processes. These efforts have been advanced through study of past global climate changes to understand mechanisms that play a role in determining natural climate fluctuations observed in ice cores, lake and sea sediments, corals, paleo-groundwater, cave deposits, tree rings, and other archives. Predictive models incorporating natural and human-induced climate change processes contribute to a better appreciation for the sensitivity of climate to specific anthropogenic perturbations. Increasingly, isotopes are being integrated in climate change studies. For example, isotope methodologies offer substantial improvements in the ability to label the origin and fate of greenhouse gases, and for studying the water and carbon cycle response to past climate changes, a high priority area for action identified by the Intergovernmental Panel on Climate Change (IPCC). Isotopes are also widely used as diagnostic variables for validation of models aimed at providing a prognosis of future environmental conditions. The International Atomic Energy Agency (IAEA) has long supported research and development of isotope applications for climate studies. The joint IAEA/WMO Global Network for Isotopes in Precipitation managed by the IAEA has for the last four decades provided the basic isotope data necessary for integrating stable oxygen and hydrogen isotopes in climate models. The IAEA has also sponsored co-ordinated research projects on Isotope Variations of Carbon Dioxide and other Trace Gases in the Atmosphere and Isotope-Aided Studies of Atmospheric Carbon Dioxide

Proceedings of the study of environmental change using isotope techniques

International Nuclear Information System (INIS)

2002-01-01

Global warming is acknowledged as a major crisis facing society today, principally due to anticipated impacts on the environment, and availability and distribution of water resources. Scientific understanding of recent human-induced climate change, as well as evaluation of potential mitigation strategies, is progressively being developed through studies of atmospheric greenhouse gases and modern water energy carbon cycling processes. These efforts have been advanced through study of past global climate changes to understand mechanisms that play a role in determining natural climate fluctuations observed in ice cores, lake and sea sediments, corals, paleo-groundwater, cave deposits, tree rings, and other archives. Predictive models incorporating natural and human-induced climate change processes contribute to a better appreciation for the sensitivity of climate to specific anthropogenic perturbations. Increasingly, isotopes are being integrated in climate change studies. For example, isotope methodologies offer substantial improvements in the ability to label the origin and fate of greenhouse gases, and for studying the water and carbon cycle response to past climate changes, a high priority area for action identified by the Intergovernmental Panel on Climate Change (IPCC). Isotopes are also widely used as diagnostic variables for validation of models aimed at providing a prognosis of future environmental conditions. The International Atomic Energy Agency (IAEA) has long supported research and development of isotope applications for climate studies. The joint IAEA/WMO Global Network for Isotopes in Precipitation managed by the IAEA has for the last four decades provided the basic isotope data necessary for integrating stable oxygen and hydrogen isotopes in climate models. The IAEA has also sponsored co-ordinated research projects on Isotope Variations of Carbon Dioxide and other Trace Gases in the Atmosphere and Isotope-Aided Studies of Atmospheric Carbon Dioxide

Stable isotope discrimination factors and between-tissue isotope comparisons for bone and skin from captive and wild green sea turtles (Chelonia mydas).

Science.gov (United States)

Turner Tomaszewicz, Calandra N; Seminoff, Jeffrey A; Price, Mike; Kurle, Carolyn M

2017-11-30

The ecological application of stable isotope analysis (SIA) relies on taxa- and tissue-specific stable carbon (Δ 13 C) and nitrogen (Δ 15 N) isotope discrimination factors, determined with captive animals reared on known diets for sufficient time to reflect dietary isotope ratios. However, captive studies often prohibit lethal sampling, are difficult with endangered species, and reflect conditions not experienced in the wild. We overcame these constraints and determined the Δ 13 C and Δ 15 N values for skin and cortical bone from green sea turtles (Chelonia mydas) that died in captivity and evaluated the utility of a mathematical approach to predict discrimination factors. Using stable carbon (δ 13 C values) and nitrogen (δ 15 N values) isotope ratios from captive and wild turtles, we established relationships between bone stable isotope (SI) ratios and those from skin, a non-lethally sampled tissue, to facilitate comparisons of SI ratios among studies using multiple tissues. The mean (±SD) Δ 13 C and Δ 15 N values (‰) between skin and bone from captive turtles and their diet (non-lipid-extracted) were 2.3 ± 0.3 and 4.1 ± 0.4 and 2.1 ± 0.6 and 5.1 ± 1.1, respectively. The mathematically predicted Δ 13 C and Δ 15 N values were similar (to within 1‰) to the experimentally derived values. The mean δ 15 N values from bone were higher than those from skin for captive (+1.0 ± 0.9‰) and wild (+0.8 ± 1.0‰) turtles; the mean δ 13 C values from bone were lower than those from skin for wild turtles (-0.6 ± 0.9‰), but the same as for captive turtles. We used linear regression equations to describe bone vs skin relationships and create bone-to-skin isotope conversion equations. For sea turtles, we provide the first (a) bone-diet SI discrimination factors, (b) comparison of SI ratios from individual-specific bone and skin, and (c) evaluation of the application of a mathematical approach to predict stable isotope discrimination factors. Our approach

Non-traditional Stable Isotope Systematics of Seafloor Hydrothermal Systems

Science.gov (United States)

Rouxel, O. J.

2009-05-01

Seafloor hydrothermal activity at mid-ocean ridges is one of the fundamental processes controlling the chemistry of the oceans and the altered oceanic crust. Past studies have demonstrated the complexity and diversity of seafloor hydrothermal systems and have highlighted the importance of subsurface environments in controlling the composition of hydrothermal fluids and mineralization types. Traditionally, the behavior of metals in seafloor hydrothermal systems have been investigated by integrating results from laboratory studies, theoretical models, mineralogy and fluid and mineral chemistry. Isotope ratios of various metals and metalloids, such as Fe, Cu, Zn, Se, Cd and Sb have recently provided new approaches for the study of seafloor hydrothermal systems. Despite these initial investigations, the cause of the isotopic variability of these elements remains poorly constrained. We have little understanding of the isotope variations between vent types (black or white smokers) as well as the influence of source rock composition (basalt, felsic or ultrabasic rocks) and alteration types. Here, I will review and present new results of metal isotope systematics of seafloor hydrothermal systems, in particular: (1) determination of empirical isotope fractionation factors for Zn, Fe and Cu-isotopes through isotopic analysis of mono-mineralic sulfide grains lining the internal chimney wall in contact with hydrothermal fluid; (2) comparison of Fe- and Cu-isotope signatures of vent fluids from mid- oceanic and back-arc hydrothermal fields, spanning wide ranges of pH, temperature, metal concentrations and contributions of magmatic fluids enriched in SO2. Ultimately, the use of complementary non-traditional stable isotope systems may help identify and constrain the complex interactions between fluids,minerals, and organisms in seafloor hydrothermal systems.

Applied systems ecology: models, data, and statistical methods

Energy Technology Data Exchange (ETDEWEB)

Eberhardt, L L

1976-01-01

In this report, systems ecology is largely equated to mathematical or computer simulation modelling. The need for models in ecology stems from the necessity to have an integrative device for the diversity of ecological data, much of which is observational, rather than experimental, as well as from the present lack of a theoretical structure for ecology. Different objectives in applied studies require specialized methods. The best predictive devices may be regression equations, often non-linear in form, extracted from much more detailed models. A variety of statistical aspects of modelling, including sampling, are discussed. Several aspects of population dynamics and food-chain kinetics are described, and it is suggested that the two presently separated approaches should be combined into a single theoretical framework. It is concluded that future efforts in systems ecology should emphasize actual data and statistical methods, as well as modelling.

Feeding ecology of Rhabdosargus holubi (family Sparidae) in multiple vegetated refugia of selected warm temperate estuaries in South Africa

Science.gov (United States)

Nel, L.; Strydom, N. A.; Perissinotto, R.; Adams, J. B.; Lemley, D. A.

2017-10-01

Estuarine marine-dependent species, such as Rhabdosargus holubi, depend greatly on structured sheltered environments and important feeding areas provided by estuaries. In this study, we investigate the ecological feeding niches of the estuarine marine-dependent sparid, R. holubi, by using conventional stomach contents and stable isotope methods (δ13C and δ15N signatures). The study has been carried out in five temperate estuaries in order to understand how fish feed in multiple intertidal vegetated habitats. These habitats included the submerged seagrass, Zostera capensis, and both previously unexplored small intertidal cord grass, Spartina maritima, and the common reed, Phragmites australis. The diet varied amongst habitats, estuaries and fish sizes and data consistently confirmed their omnivorous diet relating to ontogenetic niche shifts. Stomach contents revealed the importance of benthic prey within both the S. maritima and P. australis habitats in the absence of large intertidal vegetation, available during low tides. Similarly, isotopic mixing models showed that R. holubi from these habitats have a greater isotopic niche compared to the Z. capensis habitat, due to their limited availability during the falling tide, suggesting migration between available habitats. Stable isotopes confirmed that R. holubi actively feeds on the epiphytic algae (especially diatoms) covering the leaves and stalks of plant matter, as supported by Bayesian mixing models. These findings add to the current knowledge regarding habitat partitioning in multiple aquatic vegetation types critical to fish ecology and the effective management and conservation of estuaries.

Carbon isotopes in the ocean model of the Community Earth System Model (CESM1

Directory of Open Access Journals (Sweden)

A. Jahn

2015-08-01

Full Text Available Carbon isotopes in the ocean are frequently used as paleoclimate proxies and as present-day geochemical ocean tracers. In order to allow a more direct comparison of climate model results with this large and currently underutilized data set, we added a carbon isotope module to the ocean model of the Community Earth System Model (CESM, containing the cycling of the stable isotope 13C and the radioactive isotope 14C. We implemented the 14C tracer in two ways: in the "abiotic" case, the 14C tracer is only subject to air–sea gas exchange, physical transport, and radioactive decay, while in the "biotic" version, the 14C additionally follows the 13C tracer through all biogeochemical and ecological processes. Thus, the abiotic 14C tracer can be run without the ecosystem module, requiring significantly fewer computational resources. The carbon isotope module calculates the carbon isotopic fractionation during gas exchange, photosynthesis, and calcium carbonate formation, while any subsequent biological process such as remineralization as well as any external inputs are assumed to occur without fractionation. Given the uncertainty associated with the biological fractionation during photosynthesis, we implemented and tested three parameterizations of different complexity. Compared to present-day observations, the model is able to simulate the oceanic 14C bomb uptake and the 13C Suess effect reasonably well compared to observations and other model studies. At the same time, the carbon isotopes reveal biases in the physical model, for example, too sluggish ventilation of the deep Pacific Ocean.