The relative roles of local climate adaptation and phylogeny in determining leaf-out timing of temperate tree species

Directory of Open Access Journals (Sweden)

Elsa Desnoues

2017-12-01

Full Text Available Background Leaf out times of temperate forest trees are a prominent determinant of global carbon dynamics throughout the year. Abiotic cues of leaf emergence are well studied but investigation of the relative roles of shared evolutionary history (phylogeny and local adaptation to climate in determining the species-level responses to these cues is needed to better apprehend the effect of global change on leaf emergence. We explored the relative importance of phylogeny and climate in determining the innate leaf out phenology across the temperate biome. Methods We used an extensive dataset of leaf-out dates of 1126 temperate woody species grown in eight Northern Hemisphere common gardens. For these species, information on the native climate and phylogenetic position was collected. Using linear regression analyses, we examine the relative effect of climate variables and phylogeny on leaf out variation among species. Results Climate variables explained twice as much variation in leaf out timing as phylogenetic information, a process that was driven primarily by the complex interactive effects of multiple climate variables. Although the primary climate factors explaining species-level variation in leaf-out timing varied drastically across different families, our analyses reveal that local adaptation plays a stronger role than common evolutionary history in determining tree phenology across the temperate biome. Conclusions In the long-term, the direct effects of physiological adaptation to abiotic effects of climate change on forest phenology are likely to outweigh the indirect effects mediated through changes in tree species composition.

Staying cool: preadaptation to temperate climates required for colonising tropical alpine-like environments

Directory of Open Access Journals (Sweden)

Berit Gehrke

2018-04-01

Full Text Available Plant species tend to retain their ancestral ecology, responding to temporal, geographic and climatic changes by tracking suitable habitats rather than adapting to novel conditions. Nevertheless, transitions into different environments or biomes still seem to be common. Especially intriguing are the tropical alpine-like areas found on only the highest mountainous regions surrounded by tropical environments. Tropical mountains are hotspots of biodiversity, often with striking degrees of endemism at higher elevations. On these mountains, steep environmental gradients and high habitat heterogeneity within small spaces coincide with astounding species diversity of great conservation value. The analysis presented here shows that the importance of in situ speciation in tropical alpine-like areas has been underestimated. Additionally and contrary to widely held opinion, the impact of dispersal from other regions with alpine-like environments is relatively minor compared to that of immigration from other biomes with a temperate (but not alpine-like climate. This suggests that establishment in tropical alpine-like regions is favoured by preadaptation to a temperate, especially aseasonal, freezing regime such as the cool temperate climate regions in the Tropics. Furthermore, emigration out of an alpine-like environment is generally rare, suggesting that alpine-like environments – at least tropical ones – are species sinks.

The effects of climate stability on northern temperate forests

DEFF Research Database (Denmark)

Ma, Ziyu

2016-01-01

a small subset of phylogenetic lineages. For current climate change, I examined the broad-scale dynamics of climate-sensitive boreal forest on a decadal time scale. Using global remote sensing data and machine learning, I tested for associations between spatial patterns of tree cover change with possible...... drivers, i.e., climate anomalies, permafrost, fire, and human activities from years 2000 to 2010. The results showed tree cover change links to fire prevalence and rising temperature in permafrost zones, suggesting impacts of permafrost thawing on large-scale tree cover dynamics in the boreal zone...

Influence of climate change on the flowering of temperate fruit trees

Science.gov (United States)

Perez-Lopez, D.; Ruiz-Ramos, M.; Sánchez-Sánchez, E.; Centeno, A.; Prieto-Egido, I.; Lopez-de-la-Franca, N.

2012-04-01

It is well known that winter chilling is necessary for the flowering of temperate trees. The chilling requirement is a criterion for choosing a species or variety at a given location. Also chemistry products can be used for reducing the chilling-hours needs but make our production more expensive. This study first analysed the observed values of chilling hours for some representative agricultural locations in Spain for the last three decades and their projected changes under climate change scenarios. Usually the chilling is measured and calculated as chilling-hours, and different methods have been used to calculate them (e.g. Richarson et al., 1974 among others) according to the species considered. For our objective North Carolina method (Shaltout and Unrath, 1983) was applied for apples, Utah method (Richardson et al. 1974) for peach and grapevine and the approach used by De Melo-Abreu et al. (2004) for olive trees. The influence of climate change in temperate trees was studied by calculating projections of chilling-hours with climate data from Regional Climate Models (RCMs) at high resolution (25 km) from the European Project ENSEMBLES (http://www.ensembles-eu.org/). These projections will allow for analysing the modelled variations of chill-hours between 2nd half of 20C and 1st half of 21C at the study locations.

Future climate change is predicted to shift long-term persistence zones in the cold-temperate kelp Laminaria hyperborea.

Science.gov (United States)

Assis, Jorge; Lucas, Ana Vaz; Bárbara, Ignacio; Serrão, Ester Álvares

2016-02-01

Global climate change is shifting species distributions worldwide. At rear edges (warmer, low latitude range margins), the consequences of small variations in environmental conditions can be magnified, producing large negative effects on species ranges. A major outcome of shifts in distributions that only recently received attention is the potential to reduce the levels of intra-specific diversity and consequently the global evolutionary and adaptive capacity of species to face novel disturbances. This is particularly important for low dispersal marine species, such as kelps, that generally retain high and unique genetic diversity at rear ranges resulting from long-term persistence, while ranges shifts during climatic glacial/interglacial cycles. Using ecological niche modelling, we (1) infer the major environmental forces shaping the distribution of a cold-temperate kelp, Laminaria hyperborea (Gunnerus) Foslie, and we (2) predict the effect of past climate changes in shaping regions of long-term persistence (i.e., climatic refugia), where this species might hypothetically harbour higher genetic diversity given the absence of bottlenecks and local extinctions over the long term. We further (3) assessed the consequences of future climate for the fate of L. hyperborea using different scenarios of greenhouse gas emissions (RCP 2.6 and RCP 8.5). Results show NW Iberia, SW Ireland and W English Channel, Faroe Islands and S Iceland, as regions where L. hyperborea may have persisted during past climate extremes until present day. All predictions for the future showed expansions to northern territories coupled with the significant loss of suitable habitats at low latitude range margins, where long-term persistence was inferred (e.g., NW Iberia). This pattern was particularly evident in the most agressive scenario of climate change (RCP 8.5), likely driving major biodiversity loss, changes in ecosystem functioning and the impoverishment of the global gene pool of L

The tropicalization of temperate marine ecosystems: climate-mediated changes in herbivory and community phase shifts

Science.gov (United States)

Vergés, Adriana; Steinberg, Peter D.; Hay, Mark E.; Poore, Alistair G. B.; Campbell, Alexandra H.; Ballesteros, Enric; Heck, Kenneth L.; Booth, David J.; Coleman, Melinda A.; Feary, David A.; Figueira, Will; Langlois, Tim; Marzinelli, Ezequiel M.; Mizerek, Toni; Mumby, Peter J.; Nakamura, Yohei; Roughan, Moninya; van Sebille, Erik; Gupta, Alex Sen; Smale, Dan A.; Tomas, Fiona; Wernberg, Thomas; Wilson, Shaun K.

2014-01-01

Climate-driven changes in biotic interactions can profoundly alter ecological communities, particularly when they impact foundation species. In marine systems, changes in herbivory and the consequent loss of dominant habitat forming species can result in dramatic community phase shifts, such as from coral to macroalgal dominance when tropical fish herbivory decreases, and from algal forests to ‘barrens’ when temperate urchin grazing increases. Here, we propose a novel phase-shift away from macroalgal dominance caused by tropical herbivores extending their range into temperate regions. We argue that this phase shift is facilitated by poleward-flowing boundary currents that are creating ocean warming hotspots around the globe, enabling the range expansion of tropical species and increasing their grazing rates in temperate areas. Overgrazing of temperate macroalgae by tropical herbivorous fishes has already occurred in Japan and the Mediterranean. Emerging evidence suggests similar phenomena are occurring in other temperate regions, with increasing occurrence of tropical fishes on temperate reefs. PMID:25009065

Control of climate and litter quality on leaf litter decomposition in different climatic zones.

Science.gov (United States)

Zhang, Xinyue; Wang, Wei

2015-09-01

Climate and initial litter quality are the major factors influencing decomposition rates on large scales. We established a comprehensive database of terrestrial leaf litter decomposition, including 785 datasets, to examine the relationship between climate and litter quality and evaluate the factors controlling decomposition on a global scale, the arid and semi-arid (AS) zone, the humid middle and humid low (HL) latitude zones. Initial litter nitrogen (N) and phosphorus (P) concentration only increased with mean annual temperature (MAT) in the AS zone and decreased with mean annual precipitation (MAP) in the HL zone. Compared with nutrient content, MAT imposed less effect on initial litter lignin content than MAP. MAT were the most important decomposition driving factors on a global scale as well as in different climatic zones. MAP only significantly affected decomposition constants in AS zone. Although litter quality parameters also showed significant influence on decomposition, their importance was less than the climatic factors. Besides, different litter quality parameters exerted significant influence on decomposition in different climatic zones. Our results emphasized that climate consistently exerted important effects on decomposition constants across different climatic zones.

Climate signals derived from cell anatomy of Scots pine in NE Germany.

Science.gov (United States)

Liang, Wei; Heinrich, Ingo; Simard, Sonia; Helle, Gerhard; Liñán, Isabel Dorado; Heinken, Thilo

2013-08-01

Tree-ring chronologies of Pinus sylvestris L. from latitudinal and altitudinal limits of the species distribution have been widely used for climate reconstructions, but there are many sites within the temperate climate zone, as is the case in northeastern Germany, at which there is little evidence of a clear climate signal in the chronologies. In this study, we developed long chronologies of several cell structure variables (e.g., average lumen area and cell wall thickness) from P. sylvestris growing in northeastern Germany and investigated the influence of climate on ring widths and cell structure variables. We found significant correlations between cell structure variables and temperature, and between tree-ring width and relative humidity and vapor pressure, respectively, enabling the development of robust reconstructions from temperate sites that have not yet been realized. Moreover, it has been shown that it may not be necessary to detrend chronologies of cell structure variables and thus low-frequency climate signals may be retrieved from longer cell structure chronologies. The relatively extensive resource of archaeological material of P. sylvestris covering approximately the last millennium may now be useful for climate reconstructions in northeastern Germany and other sites in the temperate climate zone.

An atypical case of successful resuscitation of an accidental profound hypothermia patient, occurring in a temperate climate.

LENUS (Irish Health Repository)

Coleman, E

2010-03-01

Cases of accidental profound hypothermia occur most frequently in cold, northern climates. We describe an atypical case, occurring in a temperate climate, where a hypothermic cardiac-arrested patient was successfully resuscitated using extracorporeal circulation (ECC).

Groundwater flow modelling of periods with temperate climate conditions - Forsmark

Energy Technology Data Exchange (ETDEWEB)

Joyce, Steven; Simpson, Trevor; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter; Swan, David (Serco Technical Consulting Services (United Kingdom)); Marsic, Niko (Kemakta Konsult AB (Sweden)); Follin, Sven (SF GeoLogic AB (Sweden))

2010-11-15

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different climate conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report concerns the modelling of a repository at the Forsmark site during temperate conditions; i.e. from post-closure and throughout the temperate period up until the receding shoreline leaves the modelling domain at around 12,000 AD. The collation and implementation of onsite hydrogeological and hydrogeochemical data from previous reports are used in the construction of a hydrogeological base case (reference case conceptualisation) and then in an examination of various areas of uncertainty within the current understanding by a series of model variants. The hydrogeological base case models at three different scales, 'repository', 'site' and 'regional', make use of continuous porous medium (CPM), equivalent continuous porous medium (ECPM) and discrete fracture network (DFN) models. The use of hydrogeological models allow for the investigation of the groundwater flow from a deep disposal facility to the biosphere and for the calculation of performance measures that will provide an input to the site performance assessment. The focus of the study described in this report has been to perform numerical simulations of the hydrogeological system from post-closure and throughout the temperate period. Besides providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events

Climate change affects winter chill for temperate fruit and nut trees.

Science.gov (United States)

Luedeling, Eike; Girvetz, Evan H; Semenov, Mikhail A; Brown, Patrick H

2011-01-01

Temperate fruit and nut trees require adequate winter chill to produce economically viable yields. Global warming has the potential to reduce available winter chill and greatly impact crop yields. We estimated winter chill for two past (1975 and 2000) and 18 future scenarios (mid and end 21st century; 3 Global Climate Models [GCMs]; 3 greenhouse gas emissions [GHG] scenarios). For 4,293 weather stations around the world and GCM projections, Safe Winter Chill (SWC), the amount of winter chill that is exceeded in 90% of all years, was estimated for all scenarios using the "Dynamic Model" and interpolated globally. We found that SWC ranged between 0 and about 170 Chill Portions (CP) for all climate scenarios, but that the global distribution varied across scenarios. Warm regions are likely to experience severe reductions in available winter chill, potentially threatening production there. In contrast, SWC in most temperate growing regions is likely to remain relatively unchanged, and cold regions may even see an increase in SWC. Climate change impacts on SWC differed quantitatively among GCMs and GHG scenarios, with the highest GHG leading to losses up to 40 CP in warm regions, compared to 20 CP for the lowest GHG. The extent of projected changes in winter chill in many major growing regions of fruits and nuts indicates that growers of these commodities will likely experience problems in the future. Mitigation of climate change through reductions in greenhouse gas emissions can help reduce the impacts, however, adaption to changes will have to occur. To better prepare for likely impacts of climate change, efforts should be undertaken to breed tree cultivars for lower chilling requirements, to develop tools to cope with insufficient winter chill, and to better understand the temperature responses of tree crops.

Divergence of dominant factors in soil microbial communities and functions in forest ecosystems along a climatic gradient

Science.gov (United States)

Xu, Zhiwei; Yu, Guirui; Zhang, Xinyu; He, Nianpeng; Wang, Qiufeng; Wang, Shengzhong; Xu, Xiaofeng; Wang, Ruili; Zhao, Ning

2018-03-01

Soil microorganisms play an important role in regulating nutrient cycling in terrestrial ecosystems. Most of the studies conducted thus far have been confined to a single forest biome or have focused on one or two controlling factors, and few have dealt with the integrated effects of climate, vegetation, and soil substrate availability on soil microbial communities and functions among different forests. In this study, we used phospholipid-derived fatty acid (PLFA) analysis to investigate soil microbial community structure and extracellular enzymatic activities to evaluate the functional potential of soil microbes of different types of forests in three different climatic zones along the north-south transect in eastern China (NSTEC). Both climate and forest type had significant effects on soil enzyme activities and microbial communities with considerable interactive effects. Except for soil acid phosphatase (AP), the other three enzyme activities were much higher in the warm temperate zone than in the temperate and the subtropical climate zones. The soil total PLFAs and bacteria were much higher in the temperate zone than in the warm temperate and the subtropical zones. The soil β-glucosidase (BG) and N-acetylglucosaminidase (NAG) activities were highest in the coniferous forest. Except for the soil fungi and fungi-bacteria (F/B), the different groups of microbial PLFAs were much higher in the conifer broad-leaved mixed forests than in the coniferous forests and the broad-leaved forests. In general, soil enzyme activities and microbial PLFAs were higher in primary forests than in secondary forests in temperate and warm temperate regions. In the subtropical region, soil enzyme activities were lower in the primary forests than in the secondary forests and microbial PLFAs did not differ significantly between primary and secondary forests. Different compositions of the tree species may cause variations in soil microbial communities and enzyme activities. Our results

Retrofit with Interior Insulation on Solid Masonry Walls in Cool Temperate Climates

DEFF Research Database (Denmark)

Bjarløv, Søren Peter; Finken, G.R.; Odgaard, Tommy

2015-01-01

For historic buildings, where an alteration of the exterior façade is not wanted, interior insulation can be the solution to improve the indoor climate and reduce heat loss, but might also introduce moisture problems like condensation in the wall. Capillary active/hydrophilic insulation materials...... have been introduced to cope with the moisture problem. An extensive amount of calculations indicating where the challenges lie in the complex work with interior insulation in cool temperate climate has been carried out. In areas with high precipitation like Denmark, capillary active insulation may...

Climate-based seed zones for Mexico: guiding reforestation under observed and projected climate change

Science.gov (United States)

Dante Castellanos-Acuña; Kenneth W. Vance-Borland; J. Bradley St. Clair; Andreas Hamann; Javier López-Upton; Erika Gómez-Pineda; Juan Manuel Ortega-Rodríguez; Cuauhtémoc Sáenz-Romero

2018-01-01

Seed zones for forest tree species are a widely used tool in reforestation programs to ensure that seedlings are well adapted to their planting environments. Here, we propose a climate-based seed zone system for Mexico to address observed and projected climate change. The proposed seed zone classification is based on bands of climate variables often related to genetic...

Nonrandom community assembly and high temporal turnover promote regional coexistence in tropics but not temperate zone.

Science.gov (United States)

Freestone, Amy L; Inouye, Brian D

2015-01-01

A persistent challenge for ecologists is understanding the ecological mechanisms that maintain global patterns of biodiversity, particularly the latitudinal diversity gradient of peak species richness in the tropics. Spatial and temporal variation in community composition contribute to these patterns of biodiversity, but how this variation and its underlying processes change across latitude remains unresolved. Using a model system of sessile marine invertebrates across 25 degrees of latitude, from the temperate zone to the tropics, we tested the prediction that spatial and temporal patterns of taxonomic richness and composition, and the community assembly processes underlying these patterns, will differ across latitude. Specifically, we predicted that high beta diversity (spatial variation in composition) and high temporal turnover contribute to the high species richness of the tropics. Using a standardized experimental approach that controls for several confounding factors that hinder interpretation of prior studies, we present results that support our predictions. In the temperate zone, communities were more similar across spatial scales from centimeters to tens of kilometers and temporal scales up to one year than at lower latitudes. Since the patterns at northern latitudes were congruent with a null model, stochastic assembly processes are implicated. In contrast, the communities in the tropics were a dynamic spatial and temporal mosaic, with low similarity even across small spatial scales and high temporal turnover at both local and regional scales. Unlike the temperate zone, deterministic community assembly processes such as predation likely contributed to the high beta diversity in the tropics. Our results suggest that community assembly processes and temporal dynamics vary across latitude and help structure and maintain latitudinal patterns of diversity.

Social implications of residential demand response in cool temperate climates

International Nuclear Information System (INIS)

Darby, Sarah J.; McKenna, Eoghan

2012-01-01

Residential electrical demand response (DR) offers the prospect of reducing the environmental impact of electricity use, and also the supply costs. However, the relatively small loads and numerous actors imply a large effort: response ratio. Residential DR may be an essential part of future smart grids, but how viable is it in the short to medium term? This paper reviews some DR concepts, then evaluates the propositions that households in cool temperate climates will be in a position to contribute to grid flexibility within the next decade, and that that they will allow some automated load control. Examples of demand response from around the world are discussed in order to assess the main considerations for cool climates. Different tariff types and forms of control are assessed in terms of what is being asked of electricity users, with a focus on real-time pricing and direct load control in energy systems with increasingly distributed resources. The literature points to the significance of thermal loads, supply mix, demand-side infrastructure, market regulation, and the framing of risks and opportunities associated with DR. In concentrating on social aspects of residential demand response, the paper complements the body of work on technical and economic potential. - Highlights: ► Demand response implies major change in governance of electricity systems. ► Households in cool temperate climates can be flexible, mainly with thermal loads. ► DR requires simple tariffs, appropriate enabling technology, education, and feedback. ► Need to test consumer acceptance of DR in specific conditions. ► Introduce tariffs with technologies e.g., TOU tariff plus DLC with electric vehicles.

The northern limit of corals of the genus Acropora in temperate zones is determined by their resilience to cold bleaching.

Science.gov (United States)

Higuchi, Tomihiko; Agostini, Sylvain; Casareto, Beatriz Estela; Suzuki, Yoshimi; Yuyama, Ikuko

2015-12-18

The distribution of corals in Japan covers a wide range of latitudes, encompassing tropical to temperate zones. However, coral communities in temperate zones contain only a small subset of species. Among the parameters that determine the distribution of corals, temperature plays an important role. We tested the resilience to cold stress of three coral species belonging to the genus Acropora in incubation experiments. Acropora pruinosa, which is the northernmost of the three species, bleached at 13 °C, but recovered once temperatures were increased. The two other species, A. hyacinthus and A. solitaryensis, which has a more southerly range than A. pruinosa, died rapidly after bleaching at 13 °C. The physiological effects of cold bleaching on the corals included decreased rates of photosynthesis, respiration, and calcification, similar to the physiological effects observed with bleaching due to high temperature stress. Contrasting hot bleaching, no increases in antioxidant enzyme activities were observed, suggesting that reactive oxygen species play a less important role in bleaching under cold stress. These results confirmed the importance of resilience to cold stress in determining the distribution and northern limits of coral species, as cold events causing coral bleaching and high mortality occur regularly in temperate zones.

Prevalence and genetic variability of Plesiomonas shigelloides in temperate climate surface waters of the Pannonian Plain

Directory of Open Access Journals (Sweden)

Petrušić Milivoje

2018-01-01

Full Text Available Plesiomonas shigelloides, a Gram-negative bacterium and the causative agent of intestinal diseases and extraintestinal infections in humans and animals, is most frequently found in aquatic environments in tropical or subtropical areas. The present study was designed to establish the prevalence and genetic variability of P. shigelloides in surface waters (lakes, rivers, ponds, inlets and canals located in a temperate climate zone, namely the Pannonian Plain of the northern part of Serbia and southern part of Hungary. The strains were isolated directly by plating samples on inositol-brilliant green-bile agar with neutral red or phenol red as indicators. Our results indicate that phenol red effectively facilitates differentiation of P. shigelloides from other bacteria. A number of samples were enriched using alkaline peptone water broth, peptone inositolbile broth and tetrathionate broth. The recovery of the isolates was more successful with the first medium. Out of a total of 51 water samples collected from 28 different locations, 22 samples (43.1% were found positive for P. shigelloides. Among the 37 isolated strains, 34 were from lakes (Šatrinci, Ludaš, Panonija, Krivaja, Pecs, Kapetanski rit, Pavlovci, Kovacsszenaja, Dobrodol, Vranjaš, Borkovac, Hermann Otto, Sot, Šelevrenac, Zobnatica, Palić, Orfui, Jarkovci, Čonoplja and 3 were from rivers (Danube, Sava. The strains were identified by phenotypic characteristic or by the VITEK2 system and confirmed by PCR using 23S rRNA species-specific oligos. The strains showed a high genetic variability, displaying a variety of RAPD profiles. Our results reveal for the first time a high prevalence of genetically diverse P. shigelloides populations in surface waters located in the temperate climate of central and southeastern Europe. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. OI 172058

Temporary streams in temperate zones: recognizing, monitoring and restoring transitional aquatic-terrestrial ecosystems

OpenAIRE

Stubbington, Rachel; England, Judy; Wood, Paul J.; Sefton, Catherine E.M.

2017-01-01

Temporary streams are defined by periodic flow cessation, and may experience partial or complete loss of surface water. The ecology and hydrology of these transitional aquatic-terrestrial ecosystems have received unprecedented attention in recent years. Research has focussed on the arid, semi-arid, and Mediterranean regions in which temporary systems are the dominant stream type, and those in cooler, wetter temperate regions with an oceanic climate influence are also receiving increasing atte...

The role of clothing in thermal comfort: how people dress in a temperate and humid climate in Brazil

Directory of Open Access Journals (Sweden)

Renata De Vecchi

Full Text Available Abstract Thermal insulation from clothing is one of the most important input variables used to predict the thermal comfort of a building's occupants. This paper investigates the clothing pattern in buildings with different configurations located in a temperate and humid climate in Brazil. Occupants of two kinds of buildings (three offices and two university classrooms assessed their thermal environment through 'right-here-right-now' questionnaires, while at the same time indoor climatic measurements were carried out in situ (air temperature and radiant temperature, air speed and humidity. A total of 5,036 votes from 1,161 occupants were collected. Results suggest that the clothing values adopted by occupants inside buildings were influenced by: 1 climate and seasons of the year; 2 different configurations and indoor thermal conditions; and 3 occupants' age and gender. Significant intergenerational and gender differences were found, which might be explained by differences in metabolic rates and fashion. The results also indicate that there is a great opportunity to exceed the clothing interval of the thermal comfort zones proposed by international standards such as ASHRAE 55 (2013 - 0.5 to 1.0 clo - and thereby save energy from cooling and heating systems, without compromising the occupants' indoor thermal comfort.

Groundwater flow modelling of periods with temperate climate conditions - Laxemar

International Nuclear Information System (INIS)

Joyce, Steven; Simpson, Trevor; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter; Roberts, David; Swan, David; Gylling, Bjoern; Marsic, Niko; Rhen, Ingvar

2010-12-01

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report concerns the modelling of a repository at the Laxemar-Simpevarp site during temperate climate conditions as a comparison to corresponding modelling carried out for Forsmark /Joyce et al. 2010/. The collation and implementation of onsite hydrogeological and hydrogeochemical data from previous reports are used in the construction of a Hydrogeological base case (reference case conceptualisation) and then an examination of various areas of uncertainty within the current understanding by a series of model variants. The Hydrogeological base case models at three different scales, 'repository', 'site' and 'regional' make use of a discrete fracture network (DFN) and equivalent continuous porous medium (ECPM) models. The use of hydrogeological models allow for the investigation of the groundwater flow from a deep disposal facility to the biosphere and for the calculation of performance measures that will provide an input to the site performance assessment. The focus of the study described in this report has been to perform numerical simulations of the hydrogeological system from post-closure and throughout the temperate period up until the receding shoreline leaves the modelling domain at around 15,000 AD. Besides providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events

Groundwater flow modelling of periods with temperate climate conditions - Laxemar

Energy Technology Data Exchange (ETDEWEB)

Joyce, Steven; Simpson, Trevor; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter; Roberts, David; Swan, David (Serco Technical Consulting Services (United Kingdom)); Gylling, Bjoern; Marsic, Niko (Kemakta Konsult AB, Stockholm (Sweden)); Rhen, Ingvar (SWECO Environment AB, Falun (Sweden))

2010-12-15

As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report concerns the modelling of a repository at the Laxemar-Simpevarp site during temperate climate conditions as a comparison to corresponding modelling carried out for Forsmark /Joyce et al. 2010/. The collation and implementation of onsite hydrogeological and hydrogeochemical data from previous reports are used in the construction of a Hydrogeological base case (reference case conceptualisation) and then an examination of various areas of uncertainty within the current understanding by a series of model variants. The Hydrogeological base case models at three different scales, 'repository', 'site' and 'regional' make use of a discrete fracture network (DFN) and equivalent continuous porous medium (ECPM) models. The use of hydrogeological models allow for the investigation of the groundwater flow from a deep disposal facility to the biosphere and for the calculation of performance measures that will provide an input to the site performance assessment. The focus of the study described in this report has been to perform numerical simulations of the hydrogeological system from post-closure and throughout the temperate period up until the receding shoreline leaves the modelling domain at around 15,000 AD. Besides providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events

Suitability of close-to-nature silviculture for adapting temperate European forests to climate change

NARCIS (Netherlands)

Brang, P.; Spathelf, P.; Larsen, J.B.; Bauhus, J.; Boncina, A.; Mohren, G.M.J.

2014-01-01

In many parts of Europe, close-to-nature silviculture (CNS) has been widely advocated as being the best approach for managing forests to cope with future climate change. In this review, we identify and evaluate six principles for enhancing the adaptive capacity of European temperate forests in a

Impacts of climate change on paddy rice yield in a temperate climate.

Science.gov (United States)

Kim, Han-Yong; Ko, Jonghan; Kang, Suchel; Tenhunen, John

2013-02-01

The crop simulation model is a suitable tool for evaluating the potential impacts of climate change on crop production and on the environment. This study investigates the effects of climate change on paddy rice production in the temperate climate regions under the East Asian monsoon system using the CERES-Rice 4.0 crop simulation model. This model was first calibrated and validated for crop production under elevated CO2 and various temperature conditions. Data were obtained from experiments performed using a temperature gradient field chamber (TGFC) with a CO2 enrichment system installed at Chonnam National University in Gwangju, Korea in 2009 and 2010. Based on the empirical calibration and validation, the model was applied to deliver a simulated forecast of paddy rice production for the region, as well as for the other Japonica rice growing regions in East Asia, projecting for years 2050 and 2100. In these climate change projection simulations in Gwangju, Korea, the yield increases (+12.6 and + 22.0%) due to CO2 elevation were adjusted according to temperature increases showing variation dependent upon the cultivars, which resulted in significant yield decreases (-22.1% and -35.0%). The projected yields were determined to increase as latitude increases due to reduced temperature effects, showing the highest increase for any of the study locations (+24%) in Harbin, China. It appears that the potential negative impact on crop production may be mediated by appropriate cultivar selection and cultivation changes such as alteration of the planting date. Results reported in this study using the CERES-Rice 4.0 model demonstrate the promising potential for its further application in simulating the impacts of climate change on rice production from a local to a regional scale under the monsoon climate system. © 2012 Blackwell Publishing Ltd.

Assessment of projected climate change in the Carpathian Region using the Holdridge life zone system

Science.gov (United States)

Szelepcsényi, Zoltán; Breuer, Hajnalka; Kis, Anna; Pongrácz, Rita; Sümegi, Pál

2018-01-01

In this paper, expected changes in the spatial and altitudinal distribution patterns of Holdridge life zone (HLZ) types are analysed to assess the possible ecological impacts of future climate change for the Carpathian Region, by using 11 bias-corrected regional climate model simulations of temperature and precipitation. The distribution patterns of HLZ types are characterized by the relative extent, the mean centre and the altitudinal range. According to the applied projections, the following conclusions can be drawn: (a) the altitudinal ranges are likely to expand in the future, (b) the lower and upper altitudinal limits as well as the altitudinal midpoints may move to higher altitudes, (c) a northward shift is expected for most HLZ types and (d) the magnitudes of these shifts can even be multiples of those observed in the last century. Related to the northward shifts, the HLZ types warm temperate thorn steppe and subtropical dry forest can also appear in the southern segment of the target area. However, a large uncertainty in the estimated changes of precipitation patterns was indicated by the following: (a) the expected change in the coverage of the HLZ type cool temperate steppe is extremely uncertain because there is no consensus among the projections even in terms of the sign of the change (high inter-model variability) and (b) a significant trend in the westward/eastward shift is simulated just for some HLZ types (high temporal variability). Finally, it is important to emphasize that the uncertainty of our results is further enhanced by the fact that some important aspects (e.g. seasonality of climate variables, direct CO2 effect, etc.) cannot be considered in the estimating process.

Heat stress in cows at pasture and benefit of shade in a temperate climate region

Science.gov (United States)

Veissier, Isabelle; Van laer, Eva; Palme, Rupert; Moons, Christel P. H.; Ampe, Bart; Sonck, Bart; Andanson, Stéphane; Tuyttens, Frank A. M.

2017-11-01

Under temperate climates, cattle are often at pasture in summer and are not necessarily provided with shade. We aimed at evaluating in a temperate region (Belgium) to what extent cattle may suffer from heat stress (measured through body temperature, respiration rate and panting score, cortisol or its metabolites in milk, and feces on hot days) and at assessing the potential benefits of shade. During the summer of 2012, 20 cows were kept on pasture without access to shade. During the summer of 2011, ten cows had access to shade (young trees with shade cloth hung between them), whereas ten cows had no access. Climatic conditions were quantified by the Heat Load Index (HLI). In animals without access to shade respiration rates, panting scores, rectal temperatures, and milk cortisol concentrations increased as HLI increased in both 2011 and 2012. Fecal cortisol metabolites varied with HLI in 2011 only. When cattle had access to shade, their use of shade increased as the HLI increased. This effect was more pronounced during the last part of the summer, possibly due to better acquaintance with the shade construction. In this case, shade use increased to 65% at the highest HLI (79). Shade tempered the effects on respiration, rectal temperature, and fecal cortisol metabolites. Milk cortisol was not influenced by HLI for cows using shade for > 10% of the day. Therefore, even in temperate areas, cattle may suffer from heat when they are at pasture in summer and providing shade can reduce such stress.

Environmental Survival of Mycobacterium avium subsp. paratuberculosis in Different Climatic Zones of Eastern Australia

Science.gov (United States)

Begg, Douglas J.; Dhand, Navneet K.; Watt, Bruce; Whittington, Richard J.

2014-01-01

The duration of survival of both the S and C strains of Mycobacterium avium subsp. paratuberculosis in feces was quantified in contrasting climatic zones of New South Wales, Australia, and detailed environmental temperature data were collected. Known concentrations of S and C strains in feces placed on soil in polystyrene boxes were exposed to the environment with or without the provision of shade (70%) at Bathurst, Armidale, Condobolin, and Broken Hill, and subsamples taken every 2 weeks were cultured for the presence of M. avium subsp. paratuberculosis. The duration of survival ranged from a minimum of 1 week to a maximum of 16 weeks, and the provision of 70% shade was the most important factor in extending the survival time. The hazard of death for exposed compared to shaded samples was 20 and 9 times higher for the S and C strains, respectively. Site did not affect the survival of the C strain, but for the S strain, the hazard of death was 2.3 times higher at the two arid zone sites (Broken Hill and Condobolin) than at the two temperate zone sites (Bathurst and Armidale). Temperature measurements revealed maximum temperatures exceeding 60°C and large daily temperature ranges at the soil surface, particularly in exposed boxes. PMID:24463974

Ecophysiological and anatomical characteristics of the subtropical shrub Zanthoxylum acanthopodium (Rutaceae) in conditions of a temperate continental climate (Serbia)

DEFF Research Database (Denmark)

Rakic, Tamara; Sinzar-Sekulic, Jasmina; Filipovic, Biljana

2009-01-01

The evergreen shrub Zanthoxylum acanthopodium DC. (Rutaceae), originating from warm temperate and subtropical Asia, has existed successfully in the Jevremovac Botanical Garden in Belgrade for more than 80 years. The seasonal pattern of water management in leaves, electrolyte leakage, essential oil...... composition, and leaf anatomy were examined in order to understand the resistance and viability of this subtropical shrub in the temperate continental climate of Belgrade, Serbia....

Evolution of Diurnal Asymmetry of Surface Temperature over Different Climatic Zones

Science.gov (United States)

Rajendran, V.; C T, D.; Chakravorty, A.; AghaKouchak, A.

2016-12-01

The increase in drought, flood, diseases, crop failure etc. in the recent past has created an alarm amongst the researchers. One of the main reasons behind the intensification of these environmental hazards is the recent revelation of climate change, which is generally attributed to the human induced global warming, represented by an increase in global mean temperature. However, in order to formulate policies to mitigate and prevent the threats due to global warming, its key driving factors should be analysed at high spatial and temporal resolution. Diurnal Temperature Range (DTR) is one of the indicators of global warming. The study of the evolution of the DTR is crucial, since it affects agriculture, health, ecosystems, transport, etc. Recent studies reveal that diurnal asymmetry has decreased globally, whereas a few regional studies report a contradictory pattern and attributed them to localized feedback processes. However, an evident conclusion cannot be made using the linear trend approaches employed in the past studies and the evolution of diurnal asymmetry should be investigated using non-linear trend approach for better perception. Hence, the regional evolution of DTR trend has been analysed using the spatially-temporally Multidimensional Ensemble Empirical Mode Decomposition (MEEMD) method over India and observed a positive trend in over-all mean of DTR, while its rate of increase has declined in the recent decades. Further, the grids showing negative trend in DTR is observed in arid deserts and warm-temperate grasslands and positive trend over the west coast and sub-tropical forest in the North-East. This transition predominantly began from the west coast and is stretched with an increase in magnitude. These changes are more pronounced during winter and post-monsoon seasons, especially in the arid desert and warm-temperate grasslands, where the rate of increase in minimum temperature is higher than that of the maximum temperature. These analyses suggest

Intensity of Urban Heat Islands in Tropical and Temperate Climates

Directory of Open Access Journals (Sweden)

Margarete Cristiane de Costa Trindade Amorim

2017-12-01

Full Text Available Nowadays, most of the Earth’s population lives in urban areas. The replacement of vegetation by buildings and the general soil sealing, associated with human activity, lead to a rise in cities temperature, resulting in the formation of urban heat islands. This article aims to evaluate the intensity and the hourly maintenance of the atmospheric heat islands in two climates: one tropical (Presidente Prudente, Brazil and one temperate (Rennes, France throughout 2016. For this, air temperature and hourly averages were measured and calculated using both a HOBO datalogger (U23-002—protected under the same RS3 brand and weather stations Davis Vantage PRO 2. The daily evolution of the heat islands presented characteristics that varied according to the hours and seasons of the year. For both Rennes and Presidente Prudente, the largest magnitudes occurred overnight, being more greatly expressed in the tropical environment and during the driest months (winter in the tropical city and summer in the temperate one. The variability of synoptic conditions from one month to another also leads to a great heterogeneity of UHI intensity throughout the year.

基于主成分-聚类分析法的建筑节能气候区划%Further climatic zoning of building energy efficiency based on principal component analysis and cluster analysis

Institute of Scientific and Technical Information of China (English)

张慧玲; 付祥钊

2012-01-01

Taking HDD18, CDD26, average temperature of the coldest month, average temperature of the hottest month, solar radiation in winter, solar radiation in summer, humidity ratio in winter and humidity ratio in summer as division indexes based on the analysis of climate indexes impacting the building cooling and heating energy consumptions, applies the principal component analysis and cluster analysis to building energy efficiency climatic zoning of the 270 cities in China, which are divided into the severe-cold dry heat high-solar-radiation zone, severe-cold cool high-solar-radiation zone, severe-cold summer free zone, cold slight-hot zone, temperate-hot-humid zone, temperate-cool zone and raw hot-wet zone. Describes the main climatic characteristics and geographic distribution of the seven climate zones, and clarifies the key point of building energy efficiency and the appropriate technical strategies respectively.%通过分析影响建筑冷热耗量的气候指标,提出了以采暖度日数HDD18、空调度日数CDD26、最冷月平均温度、最热月平均温度、冬季太阳辐射热量、夏季太阳辐射热量、冬季含湿量和夏季含湿量8个气候指标作为建筑节能气候区划指标,采用主成分分析与聚类分析相结合的区划方法对我国270个城市进行了建筑节能气候区划,划分为严寒干热高辐区、严寒凉爽高辐区、严寒无夏区、寒冷微热区、温和炎热湿润区、温和凉爽区和阴冷湿热区,介绍了这7个气候区的主要气候特征和主要的地理范围,明确了各区的建筑节能重点和适宜的技术策略.

Simple model for daily evaporation from fallow tilled soil under spring conditions in a temperate climate.

NARCIS (Netherlands)

Boesten, J.J.T.I.; Stroosnijder, L.

1986-01-01

A simple parametric model is presented to estimate daily evaporation from fallow tilled soil under spring conditions in a temperate climate. In this model, cumulative actual evaporation during a drying cycle is directly proportional to the square root of cumulative potential evaporation. The model

Changes in autumn vegetation dormancy onset date and the climate controls across temperate ecosystems in China from 1982 to 2010.

Science.gov (United States)

Yang, Yuting; Guan, Huade; Shen, Miaogen; Liang, Wei; Jiang, Lei

2015-02-01

Vegetation phenology is a sensitive indicator of the dynamic response of terrestrial ecosystems to climate change. In this study, the spatiotemporal pattern of vegetation dormancy onset date (DOD) and its climate controls over temperate China were examined by analysing the satellite-derived normalized difference vegetation index and concurrent climate data from 1982 to 2010. Results show that preseason (May through October) air temperature is the primary climatic control of the DOD spatial pattern across temperate China, whereas preseason cumulative precipitation is dominantly associated with the DOD spatial pattern in relatively cold regions. Temporally, the average DOD over China's temperate ecosystems has delayed by 0.13 days per year during the past three decades. However, the delay trends are not continuous throughout the 29-year period. The DOD experienced the largest delay during the 1980s, but the delay trend slowed down or even reversed during the 1990s and 2000s. Our results also show that interannual variations in DOD are most significantly related with preseason mean temperature in most ecosystems, except for the desert ecosystem for which the variations in DOD are mainly regulated by preseason cumulative precipitation. Moreover, temperature also determines the spatial pattern of temperature sensitivity of DOD, which became significantly lower as temperature increased. On the other hand, the temperature sensitivity of DOD increases with increasing precipitation, especially in relatively dry areas (e.g. temperate grassland). This finding stresses the importance of hydrological control on the response of autumn phenology to changes in temperature, which must be accounted in current temperature-driven phenological models. © 2014 John Wiley & Sons Ltd.

Cytotoxic Meroterpenoids with Rare Skeletons from Psidium guajava Cultivated in Temperate Zone

Science.gov (United States)

Qin, Xu-Jie; Yan, Huan; Ni, Wei; Yu, Mu-Yuan; Khan, Afsar; Liu, Hui; Zhang, Hong-Xia; He, Li; Hao, Xiao-Jiang; di, Ying-Tong; Liu, Hai-Yang

2016-09-01

Three new meroterpenoids, guajavadials A-C (1-3), were isolated from Psidium guajava cultivated in temperate zone. Their structures were established by extensive spectroscopic evidence and electronic circular dichroism (ECD) calculations. Guajavadial A (1) represents a novel skeleton of the 3,5-diformylbenzyl phloroglucinol-coupled monoterpenoid, while guajavadials B (2) and C (3) are new adducts of the 3,5-diformylbenzyl phloroglucinol and a sesquiterpene with different coupling models. The plausible biosynthetic pathways as well as antimicrobial and cytotoxic activities of these meroterpenoids are also discussed. All these isolates exhibited moderate cytotoxicities against five human cancer cell lines, with 3 being most effective with an IC50 value of 3.54 μM toward SMMC-7721 cell lines.

Effect of different home-cooking methods on textural and nutritional properties of sweet potato genotypes grown in temperate climate conditions.

Science.gov (United States)

Nicoletto, Carlo; Vianello, Fabio; Sambo, Paolo

2018-01-01

The European Union (EU) market for sweet potato is small but is growing considerably and and has increased by 100% over the last 5 years. The cultivation of sweet potato in temperate climate conditions has not considered extensively and could be a new opportunity for the EU market. Healthy and qualitative traits of different sweet potato cultivars grown in temperate climate conditions were evaluated in accordance with four cooking methods. Traditional cultivars showed high hardness and adhesiveness values. The highest concentrations of sugars (especially maltose) and phenolic acids (caffeic and chlorogenic) were found in samples treated by boiling and steaming. High antioxidant activity was found in fried potatoes. Qualitative traits of sweet potatoes treated by microwaves did not report any significant variation compared to the control. Traditional and new sweet potato cultivars can be cultivated in temperate climate conditions and show interesting qualitative properties, especially as a result of the presence of antioxidant compounds. Concerning global quality, colored varieties expressed a better profile than traditional Italian ones and they are suitable for the European market, giving new opportunities for consumers and producers. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

On validation of the rain climatic zone designations for Nigeria

Science.gov (United States)

Obiyemi, O. O.; Ibiyemi, T. S.; Ojo, J. S.

2017-07-01

In this paper, validation of rain climatic zone classifications for Nigeria is presented based on global radio-climatic models by the International Telecommunication Union-Radiocommunication (ITU-R) and Crane. Rain rate estimates deduced from several ground-based measurements and those earlier estimated from the precipitation index on the Tropical Rain Measurement Mission (TRMM) were employed for the validation exercise. Although earlier classifications indicated that Nigeria falls into zones P, Q, N, and K for the ITU-R designations, and zones E and H for Crane's climatic zone designations, the results however confirmed that the rain climatic zones across Nigeria can only be classified into four, namely P, Q, M, and N for the ITU-R designations, while the designations by Crane exhibited only three zones, namely E, G, and H. The ITU-R classification was found to be more suitable for planning microwave and millimeter wave links across Nigeria. The research outcomes are vital in boosting the confidence level of system designers in using the ITU-R designations as presented in the map developed for the rain zone designations for estimating the attenuation induced by rain along satellite and terrestrial microwave links over Nigeria.

Development of climatic zones and passive solar design in Madagascar

International Nuclear Information System (INIS)

Rakoto-Joseph, O.; Garde, F.; David, M.; Adelard, L.; Randriamanantany, Z.A.

2009-01-01

Climate classification is extremely useful to design buildings for thermal comfort purposes. This paper presents the first work for a climate classification of Madagascar Island. This classification is based on the meteorological data measured in different cities of this country. Three major climatic zones are identified. Psychometric charts for the six urban areas of Madagascar are proposed, and suited passive solar designs related to each climate are briefly discussed. Finally, a total of three passive design zones have been identified and appropriate design strategies such as solar heating, natural ventilation, thermal mass are suggested for each zone. The specificity of this work is that: it is the first published survey on the climate classification and the passive solar designs for this developing country

Climate change implications in the northern coastal temperate rainforest of North America

Science.gov (United States)

Shanley, Colin S.; Pyare, Sanjay; Goldstein, Michael I.; Alaback, Paul B.; Albert, David M.; Beier, Colin M.; Brinkman, Todd J.; Edwards, Rick T.; Hood, Eran; MacKinnon, Andy; McPhee, Megan V.; Patterson, Trista; Suring, Lowell H.; Tallmon, David; Wipfli, Mark S.

2015-01-01

We synthesized an expert review of climate change implications for hydroecological and terrestrial ecological systems in the northern coastal temperate rainforest of North America. Our synthesis is based on an analysis of projected temperature, precipitation, and snowfall stratified by eight biogeoclimatic provinces and three vegetation zones. Five IPCC CMIP5 global climate models (GCMs) and two representative concentration pathways (RCPs) are the basis for projections of mean annual temperature increasing from a current average (1961–1990) of 3.2 °C to 4.9–6.9 °C (5 GCM range; RCP4.5 scenario) or 6.4–8.7 °C (RCP8.5), mean annual precipitation increasing from 3130 mm to 3210–3400 mm (3–9 % increase) or 3320–3690 mm (6–18 % increase), and total precipitation as snow decreasing from 1200 mm to 940–720 mm (22–40 % decrease) or 720–500 mm (40–58 % decrease) by the 2080s (2071–2100; 30-year normal period). These projected changes are anticipated to result in a cascade of ecosystem-level effects including: increased frequency of flooding and rain-on-snow events; an elevated snowline and reduced snowpack; changes in the timing and magnitude of stream flow, freshwater thermal regimes, and riverine nutrient exports; shrinking alpine habitats; altitudinal and latitudinal expansion of lowland and subalpine forest types; shifts in suitable habitat boundaries for vegetation and wildlife communities; adverse effects on species with rare ecological niches or limited dispersibility; and shifts in anadromous salmon distribution and productivity. Our collaborative synthesis of potential impacts highlights the coupling of social and ecological systems that characterize the region as well as a number of major information gaps to help guide assessments of future conditions and adaptive capacity.

Impact of Climate Change on Temperate and Alpine Grasslands in China during 1982–2006

Directory of Open Access Journals (Sweden)

Xiangjin Shen

2015-01-01

Full Text Available Based on GIMMS NDVI and climate data from 1982 to 2006, this study analyzed the impact of climate change on grassland in China. During the growing season, there were significant effects of precipitation on the growth of all the grassland types (P<0.05, except for meadow vegetation. For the air temperatures, there existed asymmetrical effects of maximum temperature (Tmax and minimum temperature (Tmin on grassland vegetation, especially for the temperate grasslands and alpine steppe. The growing season NDVI correlated negatively with Tmax but positively with Tmin for temperate grasslands. Seasonally, these opposite effects were only observed in summer. For alpine steppe, the growing season NDVI correlated positively with Tmax but negatively with Tmin, and this pattern of asymmetrical responses was only obvious in spring and autumn. Under the background of global asymmetric warming, more attention should be paid to this asymmetric response of grassland vegetation to daytime and night-time warming, especially when we want to predict the productivity of China’s grasslands in the future.

Tree species distribution in temperate forests is more influenced by soil than by climate.

Science.gov (United States)

Walthert, Lorenz; Meier, Eliane Seraina

2017-11-01

Knowledge of the ecological requirements determining tree species distributions is a precondition for sustainable forest management. At present, the abiotic requirements and the relative importance of the different abiotic factors are still unclear for many temperate tree species. We therefore investigated the relative importance of climatic and edaphic factors for the abundance of 12 temperate tree species along environmental gradients. Our investigations are based on data from 1,075 forest stands across Switzerland including the cold-induced tree line of all studied species and the drought-induced range boundaries of several species. Four climatic and four edaphic predictors represented the important growth factors temperature, water supply, nutrient availability, and soil aeration. The climatic predictors were derived from the meteorological network of MeteoSwiss, and the edaphic predictors were available from soil profiles. Species cover abundances were recorded in field surveys. The explanatory power of the predictors was assessed by variation partitioning analyses with generalized linear models. For six of the 12 species, edaphic predictors were more important than climatic predictors in shaping species distribution. Over all species, abundances depended mainly on nutrient availability, followed by temperature, water supply, and soil aeration. The often co-occurring species responded similar to these growth factors. Drought turned out to be a determinant of the lower range boundary for some species. We conclude that over all 12 studied tree species, soil properties were more important than climate variables in shaping tree species distribution. The inclusion of appropriate soil variables in species distribution models allowed to better explain species' ecological niches. Moreover, our study revealed that the ecological requirements of tree species assessed in local field studies and in experiments are valid at larger scales across Switzerland.

Indiana bat summer maternity distribution: effects of current and future climates

Science.gov (United States)

Susan C. Loeb; Eric A. Winters

2013-01-01

Temperate zone bats may be more sensitive to climate change than other groups of mammals because many aspects of their ecology are closely linked to temperature. However, few studies have tried to predict the responses of bats to climate change. The Indiana bat (Myotis sodalis) is a federally listed endangered species that is found in the eastern...

Genetic structure of Leptopilina boulardi populations from different climatic zones of Iran

NARCIS (Netherlands)

Seyahooei, M.A.; van Alphen, J.J.M.; Kraaijeveld, K.

2011-01-01

Background The genetic structure of populations can be influenced by geographic isolation (including physical distance) and ecology. We examined these effects in Leptopilina boulardi, a parasitoid of Drosophila of African origin and widely distributed over temperate and (sub) tropical climates.

Hydrology and morphology of two river mouth regions (temperate Vistula Delta and subtropical Red River Delta

Directory of Open Access Journals (Sweden)

Zbigniew Pruszak

2005-09-01

Full Text Available The paper presents a comparative analysis of two different river mouths from two different geographical zones (subtropical and temperate climatic regions. One is the multi-branch and multi-spit mouth of the Red River on the Gulf of Tonkin (Vietnam, the other is the smaller delta of the river Vistula on a bay of the Baltic Sea (Poland. The analysis focuses on the similarities and differences in the hydrodynamics between these estuaries and the adjacent coastal zones, the features of sediment transport, and the long-term morphodynamics of the river outlets. Salinity and water level are also discussed, the latter also in the context of the anticipated global effect of accelerated sea level rise. The analysis shows that the climatic and environmental conditions associated with geographical zones give rise to fundamental differences in the generation and dynamic evolution of the river mouths.

Changes in the world rivers' discharge projected from an updated high resolution dataset of current and future climate zones

Science.gov (United States)

Santini, Monia; di Paola, Arianna

2015-12-01

In this paper, an updated global map of the current climate zoning and of its projections, according to the Köppen-Geiger classification, is first provided. The map at high horizontal resolution (0.5° × 0.5°), representative of the current (i.e. 1961-2005) conditions, is based on the Climate Research Unit dataset holding gridded series of historical observed temperature and precipitation, while projected conditions rely on the simulated series, for the same variables, by the General Circulation Model CMCC-CM. Modeled variables were corrected for their bias and then projections of climate zoning were generated for the medium term (2006-2050) and long term (2056-2100) future periods, under RCP 4.5 and RCP 8.5 emission scenarios. Results show that Equatorial and Arid climates will spread at the expenses of Snow and Polar climates, with the Warm Temperate experiencing more moderate increase. Maps of climate zones are valuable for a wide range of studies on climate change and its impacts, especially those regarding the water cycle that is strongly regulated by the combined conditions of precipitation and temperature. As example of large scale hydrological applications, in this work we tested and implemented a spatial statistical procedure, the geographically weighted regression among climate zones' surface and mean annual discharge (MAD) at hydrographic basin level, to quantify likely changes in MAD for the main world rivers monitored through the Global Runoff Data Center database. The selected river basins are representative of more than half of both global superficial freshwater resources and world's land area. Globally, a decrease in MAD is projected both in the medium term and long term, while spatial differences highlight how some areas require efforts to avoid consequences of amplified water scarcity, while other areas call for strategies to take the opportunity from the expected increase in water availability. Also the fluctuations of trends between the

Internal Flow Management in a Multi-Zone Climate Control Unit

NARCIS (Netherlands)

Persis, C. De; Jessen, J.J.; Izadi-Zamanabadi, R.; Schiøler, H.

2006-01-01

In this contribution, we examine a dynamic model describing the evolution of internal climate conditions in a closed environment partitioned into zones for which different climate conditions must be guaranteed. The zones are not separated, large air masses are exchanged among them, and the behavior

Internal flow management in a multi-zone climate control unit

DEFF Research Database (Denmark)

De Persis, C.; Jessen, Jan Jacob; Izadi-Zamanabadi, Roozbeh

2006-01-01

In this contribution, we examine a dynamic model describing the evolution of internal climate conditions in a closed environment partitioned into zones for which different climate conditions must be guaranteed. The zones are not separated, large air masses are exchanged among them, and the behavior...

A first approach to calculate BIOCLIM variables and climate zones for Antarctica

Science.gov (United States)

Wagner, Monika; Trutschnig, Wolfgang; Bathke, Arne C.; Ruprecht, Ulrike

2018-02-01

For testing the hypothesis that macroclimatological factors determine the occurrence, biodiversity, and species specificity of both symbiotic partners of Antarctic lecideoid lichens, we present a first approach for the computation of the full set of 19 BIOCLIM variables, as available at http://www.worldclim.org/ for all regions of the world with exception of Antarctica. Annual mean temperature (Bio 1) and annual precipitation (Bio 12) were chosen to define climate zones of the Antarctic continent and adjacent islands as required for ecological niche modeling (ENM). The zones are based on data for the years 2009-2015 which was obtained from the Antarctic Mesoscale Prediction System (AMPS) database of the Ohio State University. For both temperature and precipitation, two separate zonings were specified; temperature values were divided into 12 zones (named 1 to 12) and precipitation values into five (named A to E). By combining these two partitions, we defined climate zonings where each geographical point can be uniquely assigned to exactly one zone, which allows an immediate explicit interpretation. The soundness of the newly calculated climate zones was tested by comparison with already published data, which used only three zones defined on climate information from the literature. The newly defined climate zones result in a more precise assignment of species distribution to the single habitats. This study provides the basis for a more detailed continental-wide ENM using a comprehensive dataset of lichen specimens which are located within 21 different climate regions.

The impacts of climate change and disturbance on spatio-temporal trajectories of biodiversity in a temperate forest landscape.

Science.gov (United States)

Thom, Dominik; Rammer, Werner; Dirnböck, Thomas; Müller, Jörg; Kobler, Johannes; Katzensteiner, Klaus; Helm, Norbert; Seidl, Rupert

2017-02-01

1. The ongoing changes to climate challenge the conservation of forest biodiversity. Yet, in thermally limited systems, such as temperate forests, not all species groups might be affected negatively. Furthermore, simultaneous changes in the disturbance regime have the potential to mitigate climate-related impacts on forest species. Here, we (i) investigated the potential long-term effect of climate change on biodiversity in a mountain forest landscape, (ii) assessed the effects of different disturbance frequencies, severities and sizes and (iii) identified biodiversity hotspots at the landscape scale to facilitate conservation management. 2. We employed the model iLand to dynamically simulate the tree vegetation on 13 865 ha of the Kalkalpen National Park in Austria over 1000 years, and investigated 36 unique combinations of different disturbance and climate scenarios. We used simulated changes in tree cover and composition as well as projected temperature and precipitation to predict changes in the diversity of Araneae, Carabidae, ground vegetation, Hemiptera, Hymenoptera, Mollusca, saproxylic beetles, Symphyta and Syrphidae, using empirical response functions. 3. Our findings revealed widely varying responses of biodiversity indicators to climate change. Five indicators showed overall negative effects, with Carabidae, saproxylic beetles and tree species diversity projected to decrease by more than 33%. Six indicators responded positively to climate change, with Hymenoptera, Mollusca and Syrphidae diversity projected to increase more than twofold. 4. Disturbances were generally beneficial for the studied indicators of biodiversity. Our results indicated that increasing disturbance frequency and severity have a positive effect on biodiversity, while increasing disturbance size has a moderately negative effect. Spatial hotspots of biodiversity were currently found in low- to mid-elevation areas of the mountainous study landscape, but shifted to higher

Assessing the optimality of ASHRAE climate zones using high resolution meteorological data sets

Science.gov (United States)

Fils, P. D.; Kumar, J.; Collier, N.; Hoffman, F. M.; Xu, M.; Forbes, W.

2017-12-01

Energy consumed by built infrastructure constitutes a significant fraction of the nation's energy budget. According to 2015 US Energy Information Agency report, 41% of the energy used in the US was going to residential and commercial buildings. Additional research has shown that 32% of commercial building energy goes into heating and cooling the building. The American National Standards Institute and the American Society of Heating Refrigerating and Air-Conditioning Engineers Standard 90.1 provides climate zones for current state-of-practice since heating and cooling demands are strongly influenced by spatio-temporal weather variations. For this reason, we have been assessing the optimality of the climate zones using high resolution daily climate data from NASA's DAYMET database. We analyzed time series of meteorological data sets for all ASHRAE climate zones between 1980-2016 inclusively. We computed the mean, standard deviation, and other statistics for a set of meteorological variables (solar radiation, maximum and minimum temperature)within each zone. By plotting all the zonal statistics, we analyzed patterns and trends in those data over the past 36 years. We compared the means of each zone to its standard deviation to determine the range of spatial variability that exist within each zone. If the band around the mean is too large, it indicates that regions in the zone experience a wide range of weather conditions and perhaps a common set of building design guidelines would lead to a non-optimal energy consumption scenario. In this study we have observed a strong variation in the different climate zones. Some have shown consistent patterns in the past 36 years, indicating that the zone was well constructed, while others have greatly deviated from their mean indicating that the zone needs to be reconstructed. We also looked at redesigning the climate zones based on high resolution climate data. We are using building simulations models like EnergyPlus to develop

Edge effects enhance carbon uptake and its vulnerability to climate change in temperate broadleaf forests.

Science.gov (United States)

Reinmann, Andrew B; Hutyra, Lucy R

2017-01-03

Forest fragmentation is a ubiquitous, ongoing global phenomenon with profound impacts on the growing conditions of the world's remaining forest. The temperate broadleaf forest makes a large contribution to the global terrestrial carbon sink but is also the most heavily fragmented forest biome in the world. We use field measurements and geospatial analyses to characterize carbon dynamics in temperate broadleaf forest fragments. We show that forest growth and biomass increase by 89 ± 17% and 64 ± 12%, respectively, from the forest interior to edge, but ecosystem edge enhancements are not currently captured by models or approaches to quantifying regional C balance. To the extent that the findings from our research represent the forest of southern New England in the United States, we provide a preliminary estimate that edge growth enhancement could increase estimates of the region's carbon uptake and storage by 13 ± 3% and 10 ± 1%, respectively. However, we also find that forest growth near the edge declines three times faster than that in the interior in response to heat stress during the growing season. Using climate projections, we show that future heat stress could reduce the forest edge growth enhancement by one-third by the end of the century. These findings contrast studies of edge effects in the world's other major forest biomes and indicate that the strength of the temperate broadleaf forest carbon sink and its capacity to mitigate anthropogenic carbon emissions may be stronger, but also more sensitive to climate change than previous estimates suggest.

Climate-driven extinctions shape the phylogenetic structure of temperate tree floras.

Science.gov (United States)

Eiserhardt, Wolf L; Borchsenius, Finn; Plum, Christoffer M; Ordonez, Alejandro; Svenning, Jens-Christian

2015-03-01

When taxa go extinct, unique evolutionary history is lost. If extinction is selective, and the intrinsic vulnerabilities of taxa show phylogenetic signal, more evolutionary history may be lost than expected under random extinction. Under what conditions this occurs is insufficiently known. We show that late Cenozoic climate change induced phylogenetically selective regional extinction of northern temperate trees because of phylogenetic signal in cold tolerance, leading to significantly and substantially larger than random losses of phylogenetic diversity (PD). The surviving floras in regions that experienced stronger extinction are phylogenetically more clustered, indicating that non-random losses of PD are of increasing concern with increasing extinction severity. Using simulations, we show that a simple threshold model of survival given a physiological trait with phylogenetic signal reproduces our findings. Our results send a strong warning that we may expect future assemblages to be phylogenetically and possibly functionally depauperate if anthropogenic climate change affects taxa similarly. © 2015 John Wiley & Sons Ltd/CNRS.

Terminal zone glacial sediment transfer at a temperate overdeepened glacier system

Science.gov (United States)

Swift, D. A.; Cook, S. J.; Graham, D. J.; Midgley, N. G.; Fallick, A. E.; Storrar, R.; Toubes Rodrigo, M.; Evans, D. J. A.

2018-01-01

Continuity of sediment transfer through glacial systems is essential to maintain subglacial bedrock erosion, yet transfer at temperate glaciers with overdeepened beds, where subglacial fluvial sediment transport should be greatly limited by adverse slopes, remains poorly understood. Complex multiple transfer processes in temperate overdeepened systems has been indicated by the presence of large frontal moraine systems, supraglacial debris of mixed transport origin, thick basal ice sequences, and englacial thrusts and eskers. At Svínafellsjökull, thrusts comprising decimetre-thick debris-rich bands of stratified facies ice of basal origin, with a coarser size distribution and higher clast content than that observed in basal ice layers, contribute substantially to the transfer of subglacial material in the terminal zone. Entrainment and transfer of material occurs by simple shear along the upper surface of bands and by strain-induced deformation of stratified and firnified glacier ice below. Thrust material includes rounded and well-rounded clasts that are also striated, indicating that fluvial bedload is deposited as subglacial channels approach the overdeepening and then entrained along thrusts. Substantial transfer also occurs within basal ice, with facies type and debris content dependent on the hydrological connectedness of the adverse slope. A process model of transfer at glaciers with terminal overdeepenings is proposed, in which the geometry of the overdeepening influences spatial patterns of ice deformation, hydrology, and basal ice formation. We conclude that the significance of thrusting in maintaining sediment transfer continuity has likely been overlooked by glacier sediment budgets and glacial landscape evolution studies.

Spatial Heterogeneity of Climate Change Effects on Dominant Height of Larch Plantations in Northern and Northeastern China

Directory of Open Access Journals (Sweden)

Hao Zang

2016-07-01

Full Text Available Determining the response of dominant height growth to climate change is important for understanding adaption strategies. Based on 550 permanent plots from a national forest inventory and climate data across seven provinces and three climate zones, we developed a climate-sensitive dominant height growth model under a mixed-effects model framework. The mean temperature of the wettest quarter and precipitation of the wettest month were found to be statistically significant explanatory variables that markedly improved model performance. Generally, future climate change had a positive effect on stand dominant height in northern and northeastern China, but the effect showed high spatial variability linked to local climatic conditions. The range in dominant height difference between the current climate and three future BC-RCP scenarios would change from −0.61 m to 1.75 m (−6.9% to 13.5% during the period 2041–2060 and from −1.17 m to 3.28 m (−9.1% to 41.0% during the period 2061–2080 across provinces. The impacts of climate change on stand dominant height decreased as stand age increased. Forests in cold and warm temperate zones had a smaller decrease in dominant height, owing to climate change, compared with those in the mid temperate zone. Overall, future climate change could impact dominant height growth in northern and northeastern China. As spatial heterogeneity of climate change affects dominant height growth, locally specific mitigation measures should be considered in forest management.

Potential impacts of climate change on the built environment: ASHRAE climate zones, building codes and national energy efficiency

Energy Technology Data Exchange (ETDEWEB)

New, Joshua Ryan [ORNL; Kumar, Jitendra [ORNL; Hoffman, Forrest M. [ORNL

2017-10-01

Statement of the Problem: ASHRAE releases updates to 90.1 “Energy Standard for Buildings except Low-Rise Residential Buildings” every three years resulting in a 3.7%-17.3% increase in energy efficiency for buildings with each release. This is adopted by or informs building codes in nations across the globe, is the National Standard for the US, and individual states elect which release year of the standard they will enforce. These codes are built upon Standard 169 “Climatic Data for Building Design Standards,” the latest 2017 release of which defines climate zones based on 8, 118 weather stations throughout the world and data from the past 8-25 years. This data may not be indicative of the weather that new buildings built today, will see during their upcoming 30-120 year lifespan. Methodology & Theoretical Orientation: Using more modern, high-resolution datasets from climate satellites, IPCC climate models (PCM and HadGCM), high performance computing resources (Titan) and new capabilities for clustering and optimization the authors briefly analyzed different methods for redefining climate zones. Using bottom-up analysis of multiple meteorological variables which were the subject matter, experts selected as being important to energy consumption, rather than the heating/cooling degree days currently used. Findings: We analyzed the accuracy of redefined climate zones, compared to current climate zones and how the climate zones moved under different climate change scenarios, and quantified the accuracy of these methods on a local level, at a national scale for the US. Conclusion & Significance: There is likely to be a significant annual, national energy and cost (billions USD) savings that could be realized by adjusting climate zones to take into account anticipated trends or scenarios in regional weather patterns.

Biochar boosts tropical but not temperate crop yields

Science.gov (United States)

Jeffery, Simon; Abalos, Diego; Prodana, Marija; Catarina Bastos, Ana; van Groenigen, Jan Willem; Hungate, Bruce A.; Verheijen, Frank

2017-05-01

Applying biochar to soil is thought to have multiple benefits, from helping mitigate climate change [1, 2], to managing waste [3] to conserving soil [4]. Biochar is also widely assumed to boost crop yield [5, 6], but there is controversy regarding the extent and cause of any yield benefit [7]. Here we use a global-scale meta-analysis to show that biochar has, on average, no effect on crop yield in temperate latitudes, yet elicits a 25% average increase in yield in the tropics. In the tropics, biochar increased yield through liming and fertilization, consistent with the low soil pH, low fertility, and low fertilizer inputs typical of arable tropical soils. We also found that, in tropical soils, high-nutrient biochar inputs stimulated yield substantially more than low-nutrient biochar, further supporting the role of nutrient fertilization in the observed yield stimulation. In contrast, arable soils in temperate regions are moderate in pH, higher in fertility, and generally receive higher fertilizer inputs, leaving little room for additional benefits from biochar. Our findings demonstrate that the yield-stimulating effects of biochar are not universal, but may especially benefit agriculture in low-nutrient, acidic soils in the tropics. Biochar management in temperate zones should focus on potential non-yield benefits such as lime and fertilizer cost savings, greenhouse gas emissions control, and other ecosystem services.

Predicting tree biomass growth in the temperate-boreal ecotone: is tree size, age, competition or climate response most important?

Science.gov (United States)

Foster, Jane R.; Finley, Andrew O.; D'Amato, Anthony W.; Bradford, John B.; Banerjee, Sudipto

2016-01-01

As global temperatures rise, variation in annual climate is also changing, with unknown consequences for forest biomes. Growing forests have the ability to capture atmospheric CO2and thereby slow rising CO2 concentrations. Forests’ ongoing ability to sequester C depends on how tree communities respond to changes in climate variation. Much of what we know about tree and forest response to climate variation comes from tree-ring records. Yet typical tree-ring datasets and models do not capture the diversity of climate responses that exist within and among trees and species. We address this issue using a model that estimates individual tree response to climate variables while accounting for variation in individuals’ size, age, competitive status, and spatially structured latent covariates. Our model allows for inference about variance within and among species. We quantify how variables influence aboveground biomass growth of individual trees from a representative sample of 15 northern or southern tree species growing in a transition zone between boreal and temperate biomes. Individual trees varied in their growth response to fluctuating mean annual temperature and summer moisture stress. The variation among individuals within a species was wider than mean differences among species. The effects of mean temperature and summer moisture stress interacted, such that warm years produced positive responses to summer moisture availability and cool years produced negative responses. As climate models project significant increases in annual temperatures, growth of species likeAcer saccharum, Quercus rubra, and Picea glauca will vary more in response to summer moisture stress than in the past. The magnitude of biomass growth variation in response to annual climate was 92–95% smaller than responses to tree size and age. This means that measuring or predicting the physical structure of current and future forests could tell us more about future C dynamics than growth

Predicting tree biomass growth in the temperate-boreal ecotone: Is tree size, age, competition, or climate response most important?

Science.gov (United States)

Foster, Jane R; Finley, Andrew O; D'Amato, Anthony W; Bradford, John B; Banerjee, Sudipto

2016-06-01

As global temperatures rise, variation in annual climate is also changing, with unknown consequences for forest biomes. Growing forests have the ability to capture atmospheric CO2 and thereby slow rising CO2 concentrations. Forests' ongoing ability to sequester C depends on how tree communities respond to changes in climate variation. Much of what we know about tree and forest response to climate variation comes from tree-ring records. Yet typical tree-ring datasets and models do not capture the diversity of climate responses that exist within and among trees and species. We address this issue using a model that estimates individual tree response to climate variables while accounting for variation in individuals' size, age, competitive status, and spatially structured latent covariates. Our model allows for inference about variance within and among species. We quantify how variables influence aboveground biomass growth of individual trees from a representative sample of 15 northern or southern tree species growing in a transition zone between boreal and temperate biomes. Individual trees varied in their growth response to fluctuating mean annual temperature and summer moisture stress. The variation among individuals within a species was wider than mean differences among species. The effects of mean temperature and summer moisture stress interacted, such that warm years produced positive responses to summer moisture availability and cool years produced negative responses. As climate models project significant increases in annual temperatures, growth of species like Acer saccharum, Quercus rubra, and Picea glauca will vary more in response to summer moisture stress than in the past. The magnitude of biomass growth variation in response to annual climate was 92-95% smaller than responses to tree size and age. This means that measuring or predicting the physical structure of current and future forests could tell us more about future C dynamics than growth responses

Climate Change Literacy across the Critical Zone Observatory Network

Science.gov (United States)

Moore, A.; Derry, L. A.; Zabel, I.; Duggan-Haas, D.; Ross, R. M.

2017-12-01

Earth's Critical Zone extends from the top of the tree canopy to the base of the groundwater lens. Thus the Critical Zone is examined as a suite of interconnected systems and study of the CZ is inherently interdisciplinary. Climate change is an important driver of CZ processes. The US Critical Zone Observatory Network comprises nine observatories and a coordinating National Office. Educational programs and materials developed at each CZO and the National Office have been collected, reviewed, and presented on-line at the CZONO (criticalzone.org/national/education-outreach/resources). Because the CZOs are designed to observe and measure a suite of common parameters on varying geological substrates and within different ecological contexts, educational resources reflect the diversity of processes represented across the network. As climate change has a network-wide impact, the fundamental building blocks of climate change literacy are key elements in many activities within the CZONO resource collection. Carbon-cycle and hydrologic cycle processes are well-represented, with emphasis on human interactions with these resources, as well as the impact of extreme events and the changing climate. Current work on the resource collection focuses on connecting individual resources to "Teach Climate Science" project and the Teacher-Friendly Guide to Climate Change (teachclimatescience.wordpress.com). The Teacher-Friendly Guide is a manual for K-12 teachers that presents both the fundamentals of climate science alongside resources for effective teaching of this controversial topic. Using the reach of the CZO network we hope to disseminate effective climate literacy resources and support to the K-12 community.

Radiocarbon and stable carbon isotope compositions of chemically fractionated soil organic matter in a temperate-zone forest

International Nuclear Information System (INIS)

Koarashi, Jun; Iida, Takao; Asano, Tomohiro

2005-01-01

To better understand the role of soil organic matter in terrestrial carbon cycle, carbon isotope compositions in soil samples from a temperate-zone forest were measured for bulk, acid-insoluble and base-insoluble organic matter fractions separated by a chemical fractionation method. The measurements also made it possible to estimate indirectly radiocarbon ( 14 C) abundances of acid- and base-soluble organic matter fractions, through a mass balance of carbon among the fractions. The depth profiles of 14 C abundances showed that (1) bomb-derived 14 C has penetrated the first 16 cm mineral soil at least; (2) Δ 14 C values of acid-soluble organic matter fraction are considerably higher than those of other fractions; and (3) a significant amount of the bomb-derived 14 C has been preserved as the base-soluble organic matter around litter-mineral soil boundary. In contrast, no or little bomb-derived 14 C was observed for the base-insoluble fraction in all sampling depths, indicating that this recalcitrant fraction, accounting for approximately 15% of total carbon in this temperate-zone forest soil, plays a role as a long-term sink in the carbon cycle. These results suggest that bulk soil organic matter cannot provide a representative indicator as a source or a sink of carbon in soil, particularly on annual to decadal timescales

Evidence of climatic effects on soil, vegetation and landform in temperate forests of south-eastern Australia

Science.gov (United States)

Inbar, Assaf; Nyman, Petter; Lane, Patrick; Sheridan, Gary

2016-04-01

Water and radiation are unevenly distributed across the landscape due to variations in topography, which in turn causes water availability differences on the terrain according to elevation and aspect orientation. These differences in water availability can cause differential distribution of vegetation types and indirectly influence the development of soil and even landform, as expressed in hillslope asymmetry. While most of the research on the effects of climate on the vegetation and soil development and landscape evolution has been concentrated in drier semi-arid areas, temperate forested areas has been poorly studied, particularly in South Eastern Australia. This study uses soil profile descriptions and data on soil depth and landform across climatic gradients to explore the degrees to which coevolution of vegetation, soils and landform are controlled by radiative forcing and rainfall. Soil depth measurements were made on polar and equatorial facing hillslopes located at 3 sites along a climatic gradient (mean annual rainfall between 700 - 1800 mm yr-1) in the Victorian Highlands, where forest types range from dry open woodland to closed temperate rainforest. Profile descriptions were taken from soil pits dag on planar hillslopes (50 m from ridge), and samples were taken from each horizon for physical and chemical properties analysis. Hillslope asymmetry in different precipitation regimes of the study region was quantified from Digital Elevation Models (DEMs). Significant vegetation differences between aspects were noted in lower and intermediate rainfall sites, where polar facing aspects expressed higher overall biomass than the drier equatorial slope. Within the study domain, soil depth was strongly correlated with forest type and above ground biomass. Soil depths and chemical properties varied between topographic aspects and along the precipitation gradient, where wetter conditions facilitate deeper and more weathered soils. Furthermore, soil depths showed

Climatic zones of solar radiation of Galicia; Zonas climaticas de radiacion solar de Galicia

Energy Technology Data Exchange (ETDEWEB)

Vazquez, M.; Izquierdo, P.; Pose, M.; Prado, M. T.; Santos, J.

2008-07-01

The paper shows the results of a research on the solar radiation received in Galicia that allows assigning each one of the 315 Galician municipalities to one of the Climatic Zones of solar radiation, defined in the Spanish Building Technical Code (BTC). It is proposed to complete the assignment of climatic Zones in the BTC with a new zone, named Climatic Zone 0, with the objective to differentiate the geographical areas in Galicia with less than 3.4 kWh/m{sup 2}.day of yearly daily average solar radiation. The study is completed with the realization of a map of the Climate Zones of solar radiation of Galicia. (Author)

Comparison of atmosphere/aquatic environment concentration ratio of volatile chlorinated hydrocarbons between temperate regions and Antarctica.

Science.gov (United States)

Zoccolillo, Lelio; Amendola, Luca; Insogna, Susanna

2009-09-01

For the purpose of understanding the transport and deposition mechanisms and the air-water distribution of some volatile chlorinated hydrocarbons (VCHCs), their atmosphere/aquatic environment concentration ratio was evaluated. In addition, for the purpose of differentiating VCHC behaviour in a temperate climate from its behaviour in a polar climate, the atmosphere/aquatic environment concentration ratio evaluated in matrices from temperate zones was compared with the concentration ratio evaluated in Antarctic matrices. In order to perform air samplings also at rigid Antarctic temperatures, the sampling apparatus, consisting of a diaphragm pump and canisters, was suitably modified. Chloroform, 1,1,1-trichloroethane, tetrachloromethane, 1,1,2-trichloroethylene and tetrachloroethylene were measured in air, water and snow using specific techniques composed of a purpose-made cryofocusing-trap-injector (for air samples) and a modified purge-and-trap injector (for aqueous samples) coupled to a gas chromatograph with mass spectrometric detection operating in selected ion monitoring mode. The VCHCs were retrieved in all the investigated matrices, both Italian and Antarctic, with concentrations varying from tens to thousands of ng m(-3) in air and from digits to hundreds of ng kg(-1) in water and snow. The atmosphere/aquatic environment concentration ratios were always found to be lower than 1. In particular, the Italian air/water concentration ratios were smaller than the Antarctic ones, by reason of the higher atmospheric photochemical activity in temperate zones. On the other hand, the Antarctic air/snow concentration ratios proved to be largely in favour of snow with respect to the Italian ratios, thus corroborating the hypothesis of a more efficient VCHC deposition mechanism and accumulation on Antarctic snow.

Risk of severe climate change impact on the terrestrial biosphere

International Nuclear Information System (INIS)

Heyder, Ursula; Schaphoff, Sibyll; Gerten, Dieter; Lucht, Wolfgang

2011-01-01

The functioning of many ecosystems and their associated resilience could become severely compromised by climate change over the 21st century. We present a global risk analysis of terrestrial ecosystem changes based on an aggregate metric of joint changes in macroscopic ecosystem features including vegetation structure as well as carbon and water fluxes and stores. We apply this metric to global ecosystem simulations with a dynamic global vegetation model (LPJmL) under 58 WCRP CMIP3 climate change projections. Given the current knowledge of ecosystem processes and projected climate change patterns, we find that severe ecosystem changes cannot be excluded on any continent. They are likely to occur (in > 90% of the climate projections) in the boreal-temperate ecotone where heat and drought stress might lead to large-scale forest die-back, along boreal and mountainous tree lines where the temperature limitation will be alleviated, and in water-limited ecosystems where elevated atmospheric CO 2 concentration will lead to increased water use efficiency of photosynthesis. Considerable ecosystem changes can be expected above 3 K local temperature change in cold and tropical climates and above 4 K in the temperate zone. Sensitivity to temperature change increases with decreasing precipitation in tropical and temperate ecosystems. In summary, there is a risk of substantial restructuring of the global land biosphere on current trajectories of climate change.

Risk of severe climate change impact on the terrestrial biosphere

Energy Technology Data Exchange (ETDEWEB)

Heyder, Ursula; Schaphoff, Sibyll; Gerten, Dieter; Lucht, Wolfgang, E-mail: Ursula.Heyder@pik-potsdam.de, E-mail: Sibyll.Schaphoff@pik-potsdam.de [Potsdam Institute for Climate Impact Research, Telegraphenberg A62, 14473 Potsdam (Germany)

2011-07-15

The functioning of many ecosystems and their associated resilience could become severely compromised by climate change over the 21st century. We present a global risk analysis of terrestrial ecosystem changes based on an aggregate metric of joint changes in macroscopic ecosystem features including vegetation structure as well as carbon and water fluxes and stores. We apply this metric to global ecosystem simulations with a dynamic global vegetation model (LPJmL) under 58 WCRP CMIP3 climate change projections. Given the current knowledge of ecosystem processes and projected climate change patterns, we find that severe ecosystem changes cannot be excluded on any continent. They are likely to occur (in > 90% of the climate projections) in the boreal-temperate ecotone where heat and drought stress might lead to large-scale forest die-back, along boreal and mountainous tree lines where the temperature limitation will be alleviated, and in water-limited ecosystems where elevated atmospheric CO{sub 2} concentration will lead to increased water use efficiency of photosynthesis. Considerable ecosystem changes can be expected above 3 K local temperature change in cold and tropical climates and above 4 K in the temperate zone. Sensitivity to temperature change increases with decreasing precipitation in tropical and temperate ecosystems. In summary, there is a risk of substantial restructuring of the global land biosphere on current trajectories of climate change.

The effects of climate change on heating energy consumption of office buildings in different climate zones in China

Science.gov (United States)

Meng, Fanchao; Li, Mingcai; Cao, Jingfu; Li, Ji; Xiong, Mingming; Feng, Xiaomei; Ren, Guoyu

2017-06-01

Climate plays an important role in heating energy consumption owing to the direct relationship between space heating and changes in meteorological conditions. To quantify the impact, the Transient System Simulation Program software was used to simulate the heating loads of office buildings in Harbin, Tianjin, and Shanghai, representing three major climate zones (i.e., severe cold, cold, and hot summer and cold winter climate zones) in China during 1961-2010. Stepwise multiple linear regression was performed to determine the key climatic parameters influencing heating energy consumption. The results showed that dry bulb temperature (DBT) is the dominant climatic parameter affecting building heating loads in all three climate zones across China during the heating period at daily, monthly, and yearly scales (R 2 ≥ 0.86). With the continuous warming climate in winter over the past 50 years, heating loads decreased by 14.2, 7.2, and 7.1 W/m2 in Harbin, Tianjin, and Shanghai, respectively, indicating that the decreasing rate is more apparent in severe cold climate zone. When the DBT increases by 1 °C, the heating loads decrease by 253.1 W/m2 in Harbin, 177.2 W/m2 in Tianjin, and 126.4 W/m2 in Shanghai. These results suggest that the heating energy consumption can be well predicted by the regression models at different temporal scales in different climate conditions owing to the high determination coefficients. In addition, a greater decrease in heating energy consumption in northern severe cold and cold climate zones may efficiently promote the energy saving in these areas with high energy consumption for heating. Particularly, the likely future increase in temperatures should be considered in improving building energy efficiency.

Conference on the Rehabilitation of Severely Damaged Land and Freshwater Ecosystems in Temperate Zones

CERN Document Server

Woodman, M

1978-01-01

This volume contains the papers presented at a conference on "The rehabilitation of severely damaged land and freshwater eco­ systems in temperate zones", held at Reykjavik, Iceland, from 4th to 11th July, 1976. The meeting was held under the auspices of the Ecosciences Panel of the N.A.T.O. Science Committee, and the organising expenses and greater part of the expenses of the speakers and chairmen were provided by N.A.T.O. The scientific programme was planned by M. W. Holdgate and M. J. Woodman, in consultation with numerous colleagues, and especially with the Administrative Director of the Conference in Iceland, Dr. Sturla Fridriksson. Iceland proved a particularly suitable location for such a Conference. Geologically, it is one of the youngest countries 1n the world, owing its origin to the up-welling of volcanic rock along the spreading zone of the mid-Atlantic ridge within the past 20 million years. Its structure, northern oceanic situation, recent glaciation and continuing volcanic activity make it dis...

Simulating phenological shifts in French temperate forests under two climatic change scenarios and four driving global circulation models

Science.gov (United States)

Lebourgeois, François; Pierrat, Jean-Claude; Perez, Vincent; Piedallu, Christian; Cecchini, Sébastien; Ulrich, Erwin

2010-09-01

After modeling the large-scale climate response patterns of leaf unfolding, leaf coloring and growing season length of evergreen and deciduous French temperate trees, we predicted the effects of eight future climate scenarios on phenological events. We used the ground observations from 103 temperate forests (10 species and 3,708 trees) from the French Renecofor Network and for the period 1997-2006. We applied RandomForest algorithms to predict phenological events from climatic and ecological variables. With the resulting models, we drew maps of phenological events throughout France under present climate and under two climatic change scenarios (A2, B2) and four global circulation models (HadCM3, CGCM2, CSIRO2 and PCM). We compared current observations and predicted values for the periods 2041-2070 and 2071-2100. On average, spring development of oaks precedes that of beech, which precedes that of conifers. Annual cycles in budburst and leaf coloring are highly correlated with January, March-April and October-November weather conditions through temperature, global solar radiation or potential evapotranspiration depending on species. At the end of the twenty-first century, each model predicts earlier budburst (mean: 7 days) and later leaf coloring (mean: 13 days) leading to an average increase in the growing season of about 20 days (for oaks and beech stands). The A2-HadCM3 hypothesis leads to an increase of up to 30 days in many areas. As a consequence of higher predicted warming during autumn than during winter or spring, shifts in leaf coloring dates appear greater than trends in leaf unfolding. At a regional scale, highly differing climatic response patterns were observed.

Edge effects resulting from forest fragmentation enhance carbon uptake and its vulnerability to climate change in temperate broadleaf forests

Science.gov (United States)

Reinmann, A.; Hutyra, L.

2016-12-01

Forest fragmentation resulting from land use and land cover change is a ubiquitous, ongoing global phenomenon with profound impacts on the growing conditions of the world's remaining forest. However, our understanding of forest carbon dynamics and their response to climate largely comes from unfragmented forest systems, which presents an important mismatch between the landscapes we study and those we aim to characterize. The temperate broadleaf forest makes a large contribution to the global terrestrial carbon sink, but is also the most heavily fragmented forest biome in the world. We use field measurements and geospatial analyses to characterize carbon dynamics in temperate broadleaf forest fragments. We show that forest growth and biomass increase by 89 ± 17% and 64 ± 12%, respectively, from the forest interior to edge. These ecosystem edge enhancements are not currently captured by models or approaches to quantifying regional C balance, but across southern New England, USA it increases carbon uptake and storage by 12.5 ± 2.9% and 9.6 ± 1.4%, respectively. However, we also find that forest growth near the edge declines three times faster than in the interior in response to heat stress during the growing season. Using climate projections, we show that future heat stress could reduce the forest edge growth enhancement by one-third by the end of the century. These findings contrast studies of edge effects in the world's other major forest biomes and indicate that the strength of the temperate broadleaf forest carbon sink and its capacity to mitigate anthropogenic carbon emissions may be stronger, but also more sensitive to climate change than previous estimates suggest.

A Hybrid Method for Generation of Typical Meteorological Years for Different Climates of China

Directory of Open Access Journals (Sweden)

Haixiang Zang

2016-12-01

Full Text Available Since a representative dataset of the climatological features of a location is important for calculations relating to many fields, such as solar energy system, agriculture, meteorology and architecture, there is a need to investigate the methodology for generating a typical meteorological year (TMY. In this paper, a hybrid method with mixed treatment of selected results from the Danish method, the Festa-Ratto method, and the modified typical meteorological year method is proposed to determine typical meteorological years for 35 locations in six different climatic zones of China (Tropical Zone, Subtropical Zone, Warm Temperate Zone, Mid Temperate Zone, Cold Temperate Zone and Tibetan Plateau Zone. Measured weather data (air dry-bulb temperature, air relative humidity, wind speed, pressure, sunshine duration and global solar radiation, which cover the period of 1994–2015, are obtained and applied in the process of forming TMY. The TMY data and typical solar radiation data are investigated and analyzed in this study. It is found that the results of the hybrid method have better performance in terms of the long-term average measured data during the year than the other investigated methods. Moreover, the Gaussian process regression (GPR model is recommended to forecast the monthly mean solar radiation using the last 22 years (1994–2015 of measured data.

Climatic zoning for the calculation of the thermal demand of buildings in Extremadura (Spain)

Science.gov (United States)

Moral, Francisco J.; Pulido, Elena; Ruíz, Antonio; López, Fernando

2017-08-01

The present work reports on a methodology to assess the climatic severity of a particular geographic region as compared to specific information available in the current regulations. The viability for each of the 387 municipalities in the Autonomous Community of Extremadura (Spain) is analysed, making a distinction between those with reliable climate reports and those for which no such information is available. In the case study, although the weather conditions in Extremadura are quite homogeneous according to the Spanish Technical Building Code (STBC 2015) classification and most areas are associated to zone C4 (soft winters and hot summers), the southern area in the region is associated to zone D1, similar to the north of Spain, where winters and summers are cool, which does not coincide with the actual climate in the south of Extremadura. The general climatic homogeneity in Extremadura was also highlighted with the new procedure, predominating zone C4, but unexpected or unreal climatic zoning was not generated, giving place to a consistent spatial distribution of zones throughout the region. Consequently, the proposed method allows a more accurate climatic zoning of any region in agreement with the Spanish legislation on energy efficiency in buildings, which would enhance the setting of thermal demand rates according to the actual climatic characterisation of the area in which a particular municipality is located.

[Characteristics and adaptation of seasonal drought in southern China under the background of climate change. V. Seasonal drought characteristics division and assessment in southern China].

Science.gov (United States)

Huang, Wan-Hua; Sui, Yue; Yang, Xiao-Guang; Dai, Shu-Wei; Li, Mao-Song

2013-10-01

Zoning seasonal drought based on the study of drought characteristics can provide theoretical basis for formulating drought mitigation plans and improving disaster reduction technologies in different arid zones under global climate change. Based on the National standard of meteorological drought indices and agricultural drought indices and the 1959-2008 meteorological data from 268 meteorological stations in southern China, this paper analyzed the climatic background and distribution characteristics of seasonal drought in southern China, and made a three-level division of seasonal drought in this region by the methods of combining comprehensive factors and main factors, stepwise screening indices, comprehensive disaster analysis, and clustering analysis. The first-level division was with the annual aridity index and seasonal aridity index as the main indices and with the precipitation during entire year and main crop growing season as the auxiliary indices, dividing the southern China into four primary zones, including semi-arid zone, sub-humid zone, humid zone, and super-humid zone. On this basis, the four primary zones were subdivided into nine second-level zones, including one semi-arid area-temperate-cold semi-arid hilly area in Sichuan-Yunnan Plateau, three sub-humid areas of warm sub-humid area in the north of the Yangtze River, warm-tropical sub-humid area in South China, and temperate-cold sub-humid plateau area in Southwest China, three humid areas of temperate-tropical humid area in the Yangtze River Basin, warm-tropical humid area in South China, and warm humid hilly area in Southwest China, and two super-humid areas of warm-tropical super-humid area in South China and temperate-cold super-humid hilly area in the south of the Yangtze River and Southwest China. According to the frequency and intensity of multiple drought indices, the second-level zones were further divided into 29 third-level zones. The distribution of each seasonal drought zone was

Mapping urban climate zones and quantifying climate behaviors - An application on Toulouse urban area (France)

Energy Technology Data Exchange (ETDEWEB)

Houet, Thomas, E-mail: thomas.houet@univ-tlse2.fr [GEODE UMR 5602 CNRS, Universite de Toulouse, 5 allee Antonio Machado, 31058 Toulouse Cedex (France); Pigeon, Gregoire [Centre National de Recherches Meteorologiques, Meteo-France/CNRM-GAME, 42 avenue Coriolis, 31057 Toulouse Cedex (France)

2011-08-15

Facing the concern of the population to its environment and to climatic change, city planners are now considering the urban climate in their choices of planning. The use of climatic maps, such Urban Climate Zone-UCZ, is adapted for this kind of application. The objective of this paper is to demonstrate that the UCZ classification, integrated in the World Meteorological Organization guidelines, first can be automatically determined for sample areas and second is meaningful according to climatic variables. The analysis presented is applied on Toulouse urban area (France). Results show first that UCZ differentiate according to air and surface temperature. It has been possible to determine the membership of sample areas to an UCZ using landscape descriptors automatically computed with GIS and remote sensed data. It also emphasizes that climate behavior and magnitude of UCZ may vary from winter to summer. Finally we discuss the influence of climate data and scale of observation on UCZ mapping and climate characterization. - Highlights: > We proposed a method to map Urban Climate Zones and quantify their climate behaviors. > UCZ is an expert-based classification and is integrated in the WMO guidelines. > We classified 26 sample areas and quantified climate behaviors in winter/summer. > Results enhance urban heat islands and outskirts are surprisingly hottest in summer. > Influence of scale and climate data on UCZ mapping and climate evaluation is discussed. - This paper presents an automated approach to classify sample areas in a UCZ using landscape descriptors and demonstrate that climate behaviors of UCZ differ.

Climate variability and vadose zone controls on damping of transient recharge

Science.gov (United States)

Corona, Claudia R.; Gurdak, Jason J.; Dickinson, Jesse; Ferré, T.P.A.; Maurer, Edwin P.

2017-01-01

Increasing demand on groundwater resources motivates understanding of the controls on recharge dynamics so model predictions under current and future climate may improve. Here we address questions about the nonlinear behavior of flux variability in the vadose zone that may explain previously reported teleconnections between global-scale climate variability and fluctuations in groundwater levels. We use hundreds of HYDRUS-1D simulations in a sensitivity analysis approach to evaluate the damping depth of transient recharge over a range of periodic boundary conditions and vadose zone geometries and hydraulic parameters that are representative of aquifer systems of the conterminous United States (U.S). Although the models were parameterized based on U.S. aquifers, findings from this study are applicable elsewhere that have mean recharge rates between 3.65 and 730 mm yr–1. We find that mean infiltration flux, period of time varying infiltration, and hydraulic conductivity are statistically significant predictors of damping depth. The resulting framework explains why some periodic infiltration fluxes associated with climate variability dampen with depth in the vadose zone, resulting in steady-state recharge, while other periodic surface fluxes do not dampen with depth, resulting in transient recharge. We find that transient recharge in response to the climate variability patterns could be detected at the depths of water levels in most U.S. aquifers. Our findings indicate that the damping behavior of transient infiltration fluxes is linear across soil layers for a range of texture combinations. The implications are that relatively simple, homogeneous models of the vadose zone may provide reasonable estimates of the damping depth of climate-varying transient recharge in some complex, layered vadose zone profiles.

Foraging behavior, environmental parameters and nests development of Melipona colimana Ayala (Hymenoptera: Meliponini) in temperate climate of Jalisco, México.

Science.gov (United States)

Macías-Macías, J O; Tapia-Gonzalez, J M; Contreras-Escareño, F

2017-01-01

Melipona colimana Ayala is an endemic species inhabiting temperate forests of pine and oak of south of Jalisco in Mexico. During a year, it was recorded every 15 days foraging activity, environmental parameters and the development of colonies of M. colimana in its wild habitat. For five minutes every hour from 7:00 to 21:00, the bees that entered and left the hive and bringing pollen and resin were registered. Every hour the relative humidity, temperature, wind speed and light intensity was recorded and related to foraging activity. Additionally, the weight of the colonies recently transferred to wooden boxes, the number of brood combs, honey pots and pollen were registered. The time of beginning and ending of the foraging activity differs from the reports of stingless bees of tropical weather and the same happens with the pollen collection. The environmental parameters that affect other tropical stingless bees in the foraging activity also affect M. colimana in temperate climate. It was determined that the major activity season and the presence of more pollen pots in the colony is from November through February, for what it could be the best time of the year for the division and obtainance of new colonies, while the critical period of minor activity and pollen flow was during rainy season. These data may be useful for the future sustainable use of this species in temperate climate.

Variance analysis of forecasted streamflow maxima in a wet temperate climate

Science.gov (United States)

Al Aamery, Nabil; Fox, James F.; Snyder, Mark; Chandramouli, Chandra V.

2018-05-01

Coupling global climate models, hydrologic models and extreme value analysis provides a method to forecast streamflow maxima, however the elusive variance structure of the results hinders confidence in application. Directly correcting the bias of forecasts using the relative change between forecast and control simulations has been shown to marginalize hydrologic uncertainty, reduce model bias, and remove systematic variance when predicting mean monthly and mean annual streamflow, prompting our investigation for maxima streamflow. We assess the variance structure of streamflow maxima using realizations of emission scenario, global climate model type and project phase, downscaling methods, bias correction, extreme value methods, and hydrologic model inputs and parameterization. Results show that the relative change of streamflow maxima was not dependent on systematic variance from the annual maxima versus peak over threshold method applied, albeit we stress that researchers strictly adhere to rules from extreme value theory when applying the peak over threshold method. Regardless of which method is applied, extreme value model fitting does add variance to the projection, and the variance is an increasing function of the return period. Unlike the relative change of mean streamflow, results show that the variance of the maxima's relative change was dependent on all climate model factors tested as well as hydrologic model inputs and calibration. Ensemble projections forecast an increase of streamflow maxima for 2050 with pronounced forecast standard error, including an increase of +30(±21), +38(±34) and +51(±85)% for 2, 20 and 100 year streamflow events for the wet temperate region studied. The variance of maxima projections was dominated by climate model factors and extreme value analyses.

Tropical Agroecosystems: These habitats are misunderstood by the temperate zones, mismanaged by the tropics.

Science.gov (United States)

Janzen, D H

1973-12-21

I have listed some of the ways in which the lowland tropics are not such a warm and wonderful place for the farmer, some of the reasons why it may be unreasonable to expect him to cope with the problems, and some of the ways in which the temperate zones make his task more difficult. The tropics are very close to being a tragedy of the commons on a global scale (69, 103), and it is the temperate zone's shepherds and sheep who are among the greatest offenders (31). Given that the temperate zones have some limited amount of resources with which they are willing to repay the tropics, how can these resources best be spent? The first answer, without doubt, is education, and the incorporation of what is already known about the tropics into that education. Second should be the generation of secure psychological and physical resources for governments that show they are enthusiastic about the development of an SYTA. Third should be support of intensive research needed to generate the set of site-specific rules for specific, clearly identified SYTA's. The subject matter of youths' cultural programming is presumably determined by what they will need during the rest of their lives. A major component of this programming should be the teaching of the socioeconomic rules of a sustained-yield, nonexpanding economy, tuned to the concept of living within the carrying capacity of the country's or region's resources. Incorporating such a process into tropical school systems will cause a major upheaval, if for no other reason than that it will involve an evaluation of the country's resources, what standard of living is to be accepted by those living on them, and who is presently harvesting them. Of even greater impact, it will have to evaluate resources in terms of their ability to raise the standard of living by Y amount for X proportion of the people in the region, rather than in terms of their cash value on the world market. For such a change to be technologically successful, it will

Co-occurrence of viruses and mosquitoes at the vectors' optimal climate range: An underestimated risk to temperate regions?

Science.gov (United States)

Blagrove, Marcus S C; Caminade, Cyril; Waldmann, Elisabeth; Sutton, Elizabeth R; Wardeh, Maya; Baylis, Matthew

2017-06-01

Mosquito-borne viruses have been estimated to cause over 100 million cases of human disease annually. Many methodologies have been developed to help identify areas most at risk from transmission of these viruses. However, generally, these methodologies focus predominantly on the effects of climate on either the vectors or the pathogens they spread, and do not consider the dynamic interaction between the optimal conditions for both vector and virus. Here, we use a new approach that considers the complex interplay between the optimal temperature for virus transmission, and the optimal climate for the mosquito vectors. Using published geolocated data we identified temperature and rainfall ranges in which a number of mosquito vectors have been observed to co-occur with West Nile virus, dengue virus or chikungunya virus. We then investigated whether the optimal climate for co-occurrence of vector and virus varies between "warmer" and "cooler" adapted vectors for the same virus. We found that different mosquito vectors co-occur with the same virus at different temperatures, despite significant overlap in vector temperature ranges. Specifically, we found that co-occurrence correlates with the optimal climatic conditions for the respective vector; cooler-adapted mosquitoes tend to co-occur with the same virus in cooler conditions than their warmer-adapted counterparts. We conclude that mosquitoes appear to be most able to transmit virus in the mosquitoes' optimal climate range, and hypothesise that this may be due to proportionally over-extended vector longevity, and other increased fitness attributes, within this optimal range. These results suggest that the threat posed by vector-competent mosquito species indigenous to temperate regions may have been underestimated, whilst the threat arising from invasive tropical vectors moving to cooler temperate regions may be overestimated.

Can miscanthus C4 photosynthesis compete with festulolium C3 photosynthesis in a temperate climate?

DEFF Research Database (Denmark)

Jiao, Xiurong; Kørup, Kirsten; Andersen, Mathias Neumann

2017-01-01

Miscanthus, a perennial grass with C4 photosynthesis, is regarded as a promising energy crop due to its high biomass productivity. Compared with other C4 species, most miscanthus genotypes have high cold tolerances at 14 °C. However, in temperate climates, temperatures below 14 °C are common...... at each temperature level and still maintained photosynthesis after growing for a longer period at 6/4 °C. Only two of five measured miscanthus genotypes increased photosynthesis immediately after the temperature was raised again. The photosynthetic capacity of festulolium was significantly higher at 10...

Human-water interactions in Myanmar's Dry Zone under climate change

Science.gov (United States)

Taft, Linda; Evers, Mariele

2016-04-01

Understanding human-water interactions is particularly essential in countries where the economy and the people's well-being and income strongly depend on the availability and quality of sufficient water resources. Such a strong dependency on water is existent in Myanmar's Dry Zone located in the central Ayeyarwady River basin. In this area, rainfall is associated with high heterogeneity across space and time. Precipitation amounts in the Dry Zone (500-1000 mm annually) are generally less compared to other regions in Myanmar (up to 4000-6000 mm). Following the Global Climate Risk Index, Myanmar is one of the countries which were most affected by extreme weather events between 1994 and 2013. Severe drought periods e.g in the years 1997-1998, 2010 and 2014 led to crop failures and water shortage in the Dry Zone, where more than 14 mio people predominantly practice agriculture. Due to the high variability of rainfalls, farming is only possible with irrigation, mainly conducted by canal systems from the rivers and groundwater withdrawal. Myanmar is recently facing big challenges which result from comprehensive political and economic reforms since 2011. These may also include increasing water use by new industrial zones and urbanization. However, not only policy and economy modify the need for water. Variability of river runoff and changes in seasonality are expected as a result of climate change. The overarching goal of the study is to understand and increase the knowledge on human-water-climate interactions and to elaborate possible future scenarios for Myanmar's Dry Zone. It is not well studied yet how current and future climate change and increasing human impact will influence the country's abundant water resources including groundwater. Therefore, the first step of this study is to identify the major drivers within the central Ayeyarwady River basin. We are in the process of collecting and analyzing data sets and information including hydrologic and eco

Welding metallurgy of SA508 Cl II heat affected zones

International Nuclear Information System (INIS)

Alberry, P.J.; Lambert, J.A.

1982-01-01

A weld thermal simulation technique has been used to investigate the metallurgical response of SA508 class II material during welding. Dynamic Ac 1 and Ac 3 data, grain growth kinetics and continuous cooling transformation diagrams have been measured. The heat affected zone structure, grain size and precipitate distribution are described in terms of the weld thermal cycle experienced and compared with a weld heat affected zone. The as-welded hardness and tempering response of a range of possible heat affected zone structures has been established. The tempering effects of various weld thermal cycles are calculated from isothermal tempering data. The likely tempering effects during welding are estimated and compared with the tempering of actual welds during welding and in subsequent conventional post weld heat treatment. 16 figures, 6 tables

Parameter Estimation of Dynamic Multi-zone Models for Livestock Indoor Climate Control

DEFF Research Database (Denmark)

Wu, Zhuang; Stoustrup, Jakob; Heiselberg, Per

2008-01-01

, the livestock, the ventilation system and the building on the dynamic performance of indoor climate. Some significant parameters employed in the climate model as well as the airflow interaction between each conceptual zone are identified with the use of experimental time series data collected during spring......In this paper, a multi-zone modeling concept is proposed based on a simplified energy balance formulation to provide a better prediction of the indoor horizontal temperature variation inside the livestock building. The developed mathematical models reflect the influences from the weather...... and winter at a real scale livestock building in Denmark. The obtained comparative results between the measured data and the simulated output confirm that a very simple multi-zone model can capture the salient dynamical features of the climate dynamics which are needed for control purposes....

Modelling the occurrence of postflexion stages of a marine estuarine-dependent fish in temperate South African estuaries

Directory of Open Access Journals (Sweden)

Yanasivan Kisten

2017-03-01

Full Text Available The movement of postflexion larvae of marine estuarine-dependent species into estuaries is critical for the survival of fishes reliant on estuaries as nurseries. However, detailed studies focused on environmental variability experienced by postflexion larvae entering a range of estuary types under varying conditions are rare. This study assessed the in situ conditions (temperature, salinity and water clarity under which the southern African endemic fish Rhabdosargus holubi (Sparidae recruits into estuaries. Postflexion larvae were sampled in three biogeographic regions (cool temperate, warm temperate and subtropical boundary, which included three estuary types (permanently open estuaries (POEs, temporarily open/closed estuaries and estuarine lake systems on a seasonal basis, independent of each other. Rhabdosargus holubi larvae were more abundant in spring and summer, in POEs in the warm temperate region. Models predicted that higher larval occurrence in estuaries is a function of lower salinity (e.g. mesohaline zones of 5-17.9 salinity and lower water clarity (e.g. 0-0.2 Kd, light extinction coefficient, particularly for warm, temperate POEs. This re-emphasizes the importance of freshwater for optimal nursery functioning, which may be compromised by impoundments, abstraction and climate change in water-short countries like South Africa.

Ensembles-based predictions of climate change impacts on bioclimatic zones in Northeast Asia

Science.gov (United States)

Choi, Y.; Jeon, S. W.; Lim, C. H.; Ryu, J.

2017-12-01

Biodiversity is rapidly declining globally and efforts are needed to mitigate this continually increasing loss of species. Clustering of areas with similar habitats can be used to prioritize protected areas and distribute resources for the conservation of species, selection of representative sample areas for research, and evaluation of impacts due to environmental changes. In this study, Northeast Asia (NEA) was classified into 14 bioclimatic zones using statistical techniques, which are correlation analysis and principal component analysis (PCA), and the iterative self-organizing data analysis technique algorithm (ISODATA). Based on these bioclimatic classification, we predicted shift of bioclimatic zones due to climate change. The input variables include the current climatic data (1960-1990) and the future climatic data of the HadGEM2-AO model (RCP 4.5(2050, 2070) and 8.5(2050, 2070)) provided by WorldClim. Using these data, multi-modeling methods including maximum likelihood classification, random forest, and species distribution modelling have been used to project the impact of climate change on the spatial distribution of bioclimatic zones within NEA. The results of various models were compared and analyzed by overlapping each result. As the result, significant changes in bioclimatic conditions can be expected throughout the NEA by 2050s and 2070s. The overall zones moved upward and some zones were predicted to disappear. This analysis provides the basis for understanding potential impacts of climate change on biodiversity and ecosystem. Also, this could be used more effectively to support decision making on climate change adaptation.

Foraging behavior, environmental parameters and nests development of Melipona colimana Ayala (Hymenoptera: Meliponini in temperate climate of Jalisco, México

Directory of Open Access Journals (Sweden)

J. O. Macías-Macías

Full Text Available Abstract Melipona colimana Ayala is an endemic species inhabiting temperate forests of pine and oak of south of Jalisco in Mexico. During a year, it was recorded every 15 days foraging activity, environmental parameters and the development of colonies of M. colimana in its wild habitat. For five minutes every hour from 7:00 to 21:00, the bees that entered and left the hive and bringing pollen and resin were registered. Every hour the relative humidity, temperature, wind speed and light intensity was recorded and related to foraging activity. Additionally, the weight of the colonies recently transferred to wooden boxes, the number of brood combs, honey pots and pollen were registered. The time of beginning and ending of the foraging activity differs from the reports of stingless bees of tropical weather and the same happens with the pollen collection. The environmental parameters that affect other tropical stingless bees in the foraging activity also affect M. colimana in temperate climate. It was determined that the major activity season and the presence of more pollen pots in the colony is from November through February, for what it could be the best time of the year for the division and obtainance of new colonies, while the critical period of minor activity and pollen flow was during rainy season. These data may be useful for the future sustainable use of this species in temperate climate.

Ecosystems and climate interactions in the boreal zone of northern Eurasia

International Nuclear Information System (INIS)

Vygodskaya, N N; Groisman, P Ya; Tchebakova, N M; Kurbatova, J A; Panfyorov, O; Parfenova, E I; Sogachev, A F

2007-01-01

The climate system and terrestrial ecosystems interact as they change. In northern Eurasia these interactions are especially strong, span all spatial and timescales, and thus have become the subject of an international program: the Northern Eurasia Earth Science Partnership Initiative (NEESPI). Without trying to cover all areas of these interactions, this paper introduces three examples of the principal micrometeorological, mesometeorological and subcontinental feedbacks that control climate-terrestrial ecosystem interactions in the boreal zone of northern Eurasia. Positive and negative feedbacks of forest paludification, of windthrow, and of climate-forced displacement of vegetation zones are presented. Moreover the interplay of different scale feedbacks, the multi-faceted nature of ecosystems-climate interactions and their potential to affect the global Earth system are shown. It is concluded that, without a synergetic modeling approach that integrates all major feedbacks and relationships between terrestrial ecosystems and climate, reliable projections of environmental change in northern Eurasia are impossible, which will also bring into question the accuracy of global change projections

A distributed control algorithm for internal flow management in a multi-zone climate unit

NARCIS (Netherlands)

Persis, C. De; Jessen, J.J.; Izadi-Zamanabadi, R.; Schiøler, H.

2008-01-01

We examine a distributed control problem for internal flow management in a multi-zone climate unit. The problem consists of guaranteeing prescribed indoor climate conditions in a cascade connection of an arbitrarily large number of communicating zones, in which air masses are exchanged to redirect

Economic analysis of hybrid power systems (PV/diesel) in different climatic zones of Tamil Nadu

International Nuclear Information System (INIS)

Suresh Kumar, U.; Manoharan, P.S.

2014-01-01

Highlights: • Investigation on economic feasibility of PV/diesel system in various climatic zones. • HOMER is used to solve economic feasibility analysis. • By the sensitivity analysis, the net present cost is reduced. • Optimum climatic zone in Tamil Nadu, India is recommended. - Abstract: With the increasing threat to environment and the fast depleting fossil fuel resources, hybrid power systems consisting of two or more renewable energy sources such as solar PV, wind, biomass, ocean thermal-with or without the back up of diesel generator have come to the forefront. These hybrid systems are normally integrated with battery banks for total reliability; such systems have brought about better quality of life in remote areas of developing economics. The remote areas in the state of Tamil Nadu in India possess excellent renewable energy sources. These areas fall under different climatic zones, are sparsely populated and are in the process of development. Though these areas are connected to the grid, Tamil Nadu grid is not stable; it is currently experiencing 40% short fall in generation. Thus grid power is available to these remote areas only for 10 h a day and even when available, there are voltage frequency problems. This paper analyses the economic feasibility of installing and operating hybrid systems in these areas. The areas are divided into different climatic zones and the hybrid system economy is analyzed for each climatic zone on the basis of NPC (net present cost), consumption of diesel and renewable fraction for all climate zones. The analysis indicates that the interior climatic zone – the area would be the optimum climatic zone to install HPS PV/diesel. The sensitivity analysis proves that the NPC of such a system can be reduced. It is suggested that due to high initial cost, government subsidy is necessary to adopt the system on a large scale. Such a profit will encourage development of renewable energy utilization and bring about rapid

Fluctuations in the East Asian monsoon recorded by pollen assemblages in sediments from the Japan Sea off the southwestern coast of Hokkaido, Japan, from 4.3 Ma to the present

Science.gov (United States)

Igarashi, Yaeko; Irino, Tomohisa; Sawada, Ken; Song, Lu; Furota, Satoshi

2018-04-01

We reconstructed fluctuations in the East Asian monsoon and vegetation in the Japan Sea region since the middle Pliocene based on pollen data obtained from sediments collected by the Integrated Ocean Drilling Program off the southwestern coast of northern Japan. Taxodiaceae conifers Metasequoia and Cryptomeria and Sciadopityacere conifer Sciadopitys are excellent indicators of a humid climate during the monsoon. The pollen temperature index (Tp) can be used as a proxy for relative air temperature. Based on changes in vegetation and reconstructed climate over a period of 4.3 Ma, we classified the sediment sequence into six pollen zones. From 4.3 to 3.8 Ma (Zone 1), the climate fluctuated between cool/moist and warm/moist climatic conditions. Vegetation changed between warm temperate mixed forest and cool temperate conifer forest. The Neogene type tree Carya recovered under a warm/moist climate. The period from 3.8 to 2.5 Ma (Zone 2) was characterized by increased Metasequoia pollen concentration. Warm temperate mixed forest vegetation developed under a cool/moist climate. The period from 2.5 to 2.2 Ma (Zone 3) was characterized by an abrupt increase in Metasequoia and/or Cryptomeria pollen and a decrease in warm broadleaf tree pollen, indicating a cool/humid climate. The Zone 4 period (2.2-1.7 Ma) was characterized by a decrease in Metasequoia and/or Cryptomeria pollen and an increase in cool temperate conifer Picea and Tsuga pollen, indicating a cool/moist climate. The period from 1.7 to 0.3 Ma (Zone 5) was characterized by orbital-scale climate fluctuations. Cycles of abrupt increases and decreases in Cryptomeria and Picea pollen and in Tp values indicated changes between warm/humid and cold/dry climates. The alpine fern Selaginella selaginoides appeared as of 1.6 Ma. Vegetation alternated among warm mixed, cool mixed, and cool temperate conifer forests. Zone 6 (0.3 Ma to present) was characterized by a decrease in Cryptomeria pollen. The warm temperate broadleaf

Species distribution models contribute to determine the effect of climate and interspecific interactions in moving hybrid zones.

Science.gov (United States)

Engler, J O; Rödder, D; Elle, O; Hochkirch, A; Secondi, J

2013-11-01

Climate is a major factor delimiting species' distributions. However, biotic interactions may also be prominent in shaping geographical ranges, especially for parapatric species forming hybrid zones. Determining the relative effect of each factor and their interaction of the contact zone location has been difficult due to the lack of broad scale environmental data. Recent developments in species distribution modelling (SDM) now allow disentangling the relative contributions of climate and species' interactions in hybrid zones and their responses to future climate change. We investigated the moving hybrid zone between the breeding ranges of two parapatric passerines in Europe. We conducted SDMs representing the climatic conditions during the breeding season. Our results show a large mismatch between the realized and potential distributions of the two species, suggesting that interspecific interactions, not climate, account for the present location of the contact zone. The SDM scenarios show that the southerly distributed species, Hippolais polyglotta, might lose large parts of its southern distribution under climate change, but a similar gain of novel habitat along the hybrid zone seems unlikely, because interactions with the other species (H. icterina) constrain its range expansion. Thus, whenever biotic interactions limit range expansion, species may become 'trapped' if range loss due to climate change is faster than the movement of the contact zone. An increasing number of moving hybrid zones are being reported, but the proximate causes of movement often remain unclear. In a global context of climate change, we call for more interest in their interactions with climate change. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

Analysis of Global Solar Irradiance over Climatic Zones in Nigeria for Solar Energy Applications

Directory of Open Access Journals (Sweden)

Adekunle Ayodotun Osinowo

2015-01-01

Full Text Available Satellite derived solar irradiance over 25 locations in the 5 climatic zones of Nigeria (tropical rainforest TRF, Guinea savannah GS, Sahel savannah SHS, Sudan savannah SUS, and Mangrove swamp forest MSF was analyzed. To justify its use, the satellite data was tested for goodness of agreement with ground measured solar radiation data using 26-year mean monthly and daily data over 16 locations in the 5 climatic zones. The well-known R2, RMSE, MBE, and MPE statistical tests were used and good agreement was found. The 25 locations were grouped into the 5 climatic zones. Frequency distribution of global solar irradiance was done for each of the climatic zones. This showed that 46.88%, and 40.6% of the number of days (9794 over TRF and MSF, respectively, had irradiation within the range of 15.01–20.01 MJ/m2/day. For the GS, SHS, and SUS, 46.19%, 55.84% and 58.53% of the days had total irradiation within the range of 20.01–25.01 MJ/m2/day, respectively. Generally, in all the climatic zones, coefficients of variation of solar radiation were high and mean values were low in July and August. Contour maps showed that high and low values of global solar irradiance and clearness index were observed in the Northern and Southern locations of Nigeria, respectively.

Marine Biodiversity in Temperate Western Australia: Multi-Taxon Surveys of Minden and Roe Reefs

Directory of Open Access Journals (Sweden)

Zoe Richards

2016-03-01

Full Text Available A growing body of evidence indicates that temperate marine ecosystems are being tropicalised due to the poleward extension of tropical species. Such climate mediated changes in species distribution patterns have the potential to profoundly alter temperate communities, as this advance can serve to push temperate taxa, many of which are southern Australian endemics, southward. These changes can lead to cascading effects for the biodiversity and function of coastal ecosystems, including contraction of ranges/habitats of sensitive cool water species. Hence there is growing concern for the future of Australia’s temperate marine biodiversity. Here we examine the diversity and abundance of marine flora and fauna at two reefs near Perth’s metropolitan area—Minden Reef and Roe Reef. We report the presence of 427 species of marine flora and fauna from eight taxon groups occurring in the Perth metropolitan area; at least three species of which appear to be new to science. Our data also extends the known range of 15 species, and in numerous instances, thousands of kilometres south from the Kimberley or Pilbara and verifies that tropicalisation of reef communities in the Perth metropolitan area is occurring. We report the presence of 24 species endemic to south-west Australia that may be at risk of range contractions with continued ocean warming. The results of these surveys add to our knowledge of local nearshore marine environments in the Perth metropolitan area and support the growing body of evidence that indicates a diverse and regionally significant marine fauna occurs in temperate Western Australia. Regular, repeated survey work across seasons is important in order to thoroughly document the status of marine biodiversity in this significant transition zone.

Plants for passive cooling. A preliminary investigation of the use of plants for passive cooling in temperate humid climates

Energy Technology Data Exchange (ETDEWEB)

Spirn, A W; Santos, A N; Johnson, D A; Harder, L B; Rios, M W

1981-04-01

The potential of vegetation for cooling small, detached residential and commercial structures in temperate, humid climates is discussed. The results of the research are documented, a critical review of the literature is given, and a brief review of energy transfer processes is presented. A checklist of design objectives for passive cooling, a demonstration of design applications, and a palette of selected plant species suitable for passive cooling are included.

Holocene millennial/centennial-scale multiproxy cyclicity in temperate eastern Australian estuary sediments

Science.gov (United States)

Skilbeck, C. Gregory; Rolph, Timothy C.; Hill, Natalie; Woods, Jonathan; Wilkens, Roy H.

2005-05-01

We have undertaken a comparative study of down-core variation in multiproxy palaeoclimate data (magnetic susceptibility, calcium carbonate content and total organic carbon) from two coastal water bodies (Myall and Tuggerah Lakes) in temperate eastern Australia to identify local, regional and global-forcing factors within Holocene estuarine sediments. The two lakes lie within the same temperate climate zone adjacent to the Tasman Sea, but are not part of the same catchment and drain different geological provinces. One is essentially a freshwater coastal lake whereas the other is a brackish back-barrier lagoon. Despite these differences, data from two sites in each of the two lakes have allowed us to investigate and compare cyclicity in otherwise uniform, single facies sediments within the frequency range of 200-2000 years, limited by the sedimentation rate within the lakes and our sample requirements. We have auto- and cross-correlated strong periodicities at 360 years, 500-530 years, 270-290 years, 420-450 years and 210 years, and subordinate periods of 650 years, 1200-1400 years and 1800 years. Our thesis is that climate is the only regionally available mechanism available to control common millennial and centennial scale cyclicity in these sediments, given the geographical and other differences. However, regional climate may not be the dominant effect at any single time and either location. Within the range of frequency spectral peaks we have identified, several fall within known long-term periodical fluctuations of sun spot activity; however, feedback loops associated with short-term orbital variation, such as Dansgaard-Oeschger cycles, and the relationship between these and palaeo-ENSO variation, are also possible contributors. Copyright

Climate change effects on runoff, catchment phosphorus loading and lake ecological state, and potential adaptations.

Science.gov (United States)

Jeppesen, Erik; Kronvang, Brian; Meerhoff, Mariana; Søndergaard, Martin; Hansen, Kristina M; Andersen, Hans E; Lauridsen, Torben L; Liboriussen, Lone; Beklioglu, Meryem; Ozen, Arda; Olesen, Jørgen E

2009-01-01

Climate change may have profound effects on phosphorus (P) transport in streams and on lake eutrophication. Phosphorus loading from land to streams is expected to increase in northern temperate coastal regions due to higher winter rainfall and to a decline in warm temperate and arid climates. Model results suggest a 3.3 to 16.5% increase within the next 100 yr in the P loading of Danish streams depending on soil type and region. In lakes, higher eutrophication can be expected, reinforced by temperature-mediated higher P release from the sediment. Furthermore, a shift in fish community structure toward small and abundant plankti-benthivorous fish enhances predator control of zooplankton, resulting in higher phytoplankton biomass. Data from Danish lakes indicate increased chlorophyll a and phytoplankton biomass, higher dominance of dinophytes and cyanobacteria (most notably of nitrogen fixing forms), but lower abundance of diatoms and chrysophytes, reduced size of copepods and cladocerans, and a tendency to reduced zooplankton biomass and zooplankton:phytoplankton biomass ratio when lakes warm. Higher P concentrations are also seen in warm arid lakes despite reduced external loading due to increased evapotranspiration and reduced inflow. Therefore, the critical loading for good ecological state in lakes has to be lowered in a future warmer climate. This calls for adaptation measures, which in the northern temperate zone should include improved P cycling in agriculture, reduced loading from point sources, and (re)-establishment of wetlands and riparian buffer zones. In the arid Southern Europe, restrictions on human use of water are also needed, not least on irrigation.

Land use strategies to mitigate climate change in carbon dense temperate forests

Science.gov (United States)

Hudiburg, Tara W.; Berner, Logan T.; Kent, Jeffrey J.; Buotte, Polly C.; Harmon, Mark E.

2018-01-01

Strategies to mitigate carbon dioxide emissions through forestry activities have been proposed, but ecosystem process-based integration of climate change, enhanced CO2, disturbance from fire, and management actions at regional scales are extremely limited. Here, we examine the relative merits of afforestation, reforestation, management changes, and harvest residue bioenergy use in the Pacific Northwest. This region represents some of the highest carbon density forests in the world, which can store carbon in trees for 800 y or more. Oregon’s net ecosystem carbon balance (NECB) was equivalent to 72% of total emissions in 2011–2015. By 2100, simulations show increased net carbon uptake with little change in wildfires. Reforestation, afforestation, lengthened harvest cycles on private lands, and restricting harvest on public lands increase NECB 56% by 2100, with the latter two actions contributing the most. Resultant cobenefits included water availability and biodiversity, primarily from increased forest area, age, and species diversity. Converting 127,000 ha of irrigated grass crops to native forests could decrease irrigation demand by 233 billion m3⋅y−1. Utilizing harvest residues for bioenergy production instead of leaving them in forests to decompose increased emissions in the short-term (50 y), reducing mitigation effectiveness. Increasing forest carbon on public lands reduced emissions compared with storage in wood products because the residence time is more than twice that of wood products. Hence, temperate forests with high carbon densities and lower vulnerability to mortality have substantial potential for reducing forest sector emissions. Our analysis framework provides a template for assessments in other temperate regions. PMID:29555758

Simulation of whole building coupled hygrothermal-airflow transfer in different climates

International Nuclear Information System (INIS)

Qin Menghao; Walton, George; Belarbi, Rafik; Allard, Francis

2011-01-01

The coupled heat, air and moisture transfer between building envelopes and indoor air is complicated, and has a significant influence on the indoor environment and the energy performance of buildings. In the paper, a model for predicting coupled multi-zone hygrothermal-airflow transfer is presented. Both heat and moisture transfer in the building envelope and multi-zone indoor airflow are simultaneously considered; their interactions are modeled. The coupled system model is implemented into Matlab-Simulink, and is validated by using a series of testing tools and experiments. The new program is applied to investigate the moisture transfer effect on indoor air humidity and building energy consumption in different climates (hot-humid, temperate and hot-dry climates). The results show that not accounting for hygrothermal effects in modeling will result in overestimation of energy costs for hot and humid climate situations and possible over sizing of plant leading to inefficient operation.

Oceanic temperate forest versus warm temperate rainforest: a reply to Grubb et al. (2017)

DEFF Research Database (Denmark)

McGlone, Matt S.; Buitenwerf, Robert; Richardson, Sarah J.

2017-01-01

Grubb et al. (2017) point out that we (McGlone et al. 2016) erroneously stated that the definition of warm temperate rain forest (WTRF; Grubb et al. 2013) was based in part on climatic criteria. We apologise: their text made clear that this was not the case. However, they go on to say that they ‘...

Organic matter flow in the food web at a temperate heath under multifactorial climate change

DEFF Research Database (Denmark)

Andresen, Louise C.; Konestabo, Heidi S.; Maraldo, Kristine

2011-01-01

climate change factors (elevated CO2, increased temperature and drought) were investigated in a full factorial field experiment at a temperate heathland location. The combined effect of biotic and abiotic factors on nitrogen and carbon flows was traced in plant root → litter → microbe → detritivore....../omnivore → predator food‐web for one year after amendment with 15N13C2‐glycine. Isotope ratio mass spectrometry (IRMS) measurement of 15N/14N and 13C/12C in soil extracts and functional ecosystem compartments revealed that the recovery of 15N sometimes decreased through the chain of consumption, with the largest...

Hot wire TIG temper bead welding for nuclear repairs

International Nuclear Information System (INIS)

Lambert, J.A.; Gilston, P.F.

1989-08-01

A preliminary assessment has been carried out to determine the suitability of the hot wire tungsten inert gas (TIG) welding process for the repair of thick section, ferritic steel nuclear pressure vessels. The objective has been to identify a hot wire TIG temper bead procedure, suitable for repairs without post weld heat treatment. This procedure involves depositing two weld layers with carefully selected welding parameters such that overlapping thermal cycles produce a refined and tempered heat affected zone, HAZ, microstructure. (author)

Downscaling NASA Climatological Data to Produce Detailed Climate Zone Maps

Science.gov (United States)

Chandler, William S.; Hoell, James M.; Westberg, David J.; Whitlock, Charles H.; Zhang, Taiping; Stackhouse, P. W.

2011-01-01

The design of energy efficient sustainable buildings is heavily dependent on accurate long-term and near real-time local weather data. To varying degrees the current meteorological networks over the globe have been used to provide these data albeit often from sites far removed from the desired location. The national need is for access to weather and solar resource data accurate enough to use to develop preliminary building designs within a short proposal time limit, usually within 60 days. The NASA Prediction Of Worldwide Energy Resource (POWER) project was established by NASA to provide industry friendly access to globally distributed solar and meteorological data. As a result, the POWER web site (power.larc.nasa.gov) now provides global information on many renewable energy parameters and several buildings-related items but at a relatively coarse resolution. This paper describes a method of downscaling NASA atmospheric assimilation model results to higher resolution and maps those parameters to produce building climate zone maps using estimates of temperature and precipitation. The distribution of climate zones for North America with an emphasis on the Pacific Northwest for just one year shows very good correspondence to the currently defined distribution. The method has the potential to provide a consistent procedure for deriving climate zone information on a global basis that can be assessed for variability and updated more regularly.

Phase structures and morphologies of tempered CA6NM stainless steel welded by hybrid laser-arc process

Energy Technology Data Exchange (ETDEWEB)

Mirakhorli, F., E-mail: Fatemeh.mirakhorli.1@ens.etsmtl.ca [École de Technologie Supérieure, Montréal, Québec H3C 1K3 (Canada); National Research Council Canada – Aerospace, Montréal, Québec H3T 2B2 (Canada); Cao, X., E-mail: Xinjin.cao@cnrc-nrc.gc.ca [National Research Council Canada – Aerospace, Montréal, Québec H3T 2B2 (Canada); Pham, X-T., E-mail: Tan.pham@etsmtl.ca [École de Technologie Supérieure, Montréal, Québec H3C 1K3 (Canada); Wanjara, P., E-mail: Priti.wanjara@cnrc-nrc.gc.ca [National Research Council Canada – Aerospace, Montréal, Québec H3T 2B2 (Canada); Fihey, J.L., E-mail: jean-luc.fihey@etsmtl.ca [École de Technologie Supérieure, Montréal, Québec H3C 1K3 (Canada)

2017-01-15

The post-weld tempered microstructure of hybrid laser-arc welded CA6NM, a cast low carbon martensitic stainless steel, was investigated. The microstructural evolutions from the fusion zone to the base metal were characterized in detail using optical microscopy, scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD) and microhardness techniques. The fusion zone, in its post-weld tempered condition, consisted of tempered lath martensite, residual delta-ferrite with various morphologies, reversed austenite and chromium carbides. The reversed austenite, which can be detected through both EBSD and XRD techniques, was found to be finely dispersed along the martensite lath boundaries, particularly at triple junctions. Based on the EBSD analysis, the orientation relationship between the reversed austenite and the adjacent martensite laths seemed to follow the Kurdjumov-Sachs (K-S) model. The results also revealed the presence of the reversed austenite in the different regions of the heat affected zone after post-weld tempering. The microindentation hardness distribution was measured, and correlated to the evolution of the corresponding microstructure across the welds. - Highlights: •The EBSD analysis was performed on hybrid laser-arc welded CA6NM. •The FZ consisted of tempered lath martensite, reversed austenite, carbides and δ ferrite after tempering. •The reversed γ was formed along the α′ lath boundaries, particularly at triple junctions.

Genomic Analyses Reveal Demographic History and Temperate Adaptation of the Newly Discovered Honey Bee Subspecies Apis mellifera sinisxinyuan n. ssp.

Science.gov (United States)

Chen, Chao; Liu, Zhiguang; Pan, Qi; Chen, Xiao; Wang, Huihua; Guo, Haikun; Liu, Shidong; Lu, Hongfeng; Tian, Shilin; Li, Ruiqiang; Shi, Wei

2016-05-01

Studying the genetic signatures of climate-driven selection can produce insights into local adaptation and the potential impacts of climate change on populations. The honey bee (Apis mellifera) is an interesting species to study local adaptation because it originated in tropical/subtropical climatic regions and subsequently spread into temperate regions. However, little is known about the genetic basis of its adaptation to temperate climates. Here, we resequenced the whole genomes of ten individual bees from a newly discovered population in temperate China and downloaded resequenced data from 35 individuals from other populations. We found that the new population is an undescribed subspecies in the M-lineage of A. mellifera (Apis mellifera sinisxinyuan). Analyses of population history show that long-term global temperature has strongly influenced the demographic history of A. m. sinisxinyuan and its divergence from other subspecies. Further analyses comparing temperate and tropical populations identified several candidate genes related to fat body and the Hippo signaling pathway that are potentially involved in adaptation to temperate climates. Our results provide insights into the demographic history of the newly discovered A. m. sinisxinyuan, as well as the genetic basis of adaptation of A. mellifera to temperate climates at the genomic level. These findings will facilitate the selective breeding of A. mellifera to improve the survival of overwintering colonies. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Revisions of the Fish Invasiveness Screening Kit (FISK) for its application in warmer climatic zones, with particular reference to peninsular Florida.

Science.gov (United States)

Lawson, Larry L; Hill, Jeffrey E; Vilizzi, Lorenzo; Hardin, Scott; Copp, Gordon H

2013-08-01

The initial version (v1) of the Fish Invasiveness Scoring Kit (FISK) was adapted from the Weed Risk Assessment of Pheloung, Williams, and Halloy to assess the potential invasiveness of nonnative freshwater fishes in the United Kingdom. Published applications of FISK v1 have been primarily in temperate-zone countries (Belgium, Belarus, and Japan), so the specificity of this screening tool to that climatic zone was not noted until attempts were made to apply it in peninsular Florida. To remedy this shortcoming, the questions and guidance notes of FISK v1 were reviewed and revised to improve clarity and extend its applicability to broader climatic regions, resulting in changes to 36 of the 49 questions. In addition, upgrades were made to the software architecture of FISK to improve overall computational speed as well as graphical user interface flexibility and friendliness. We demonstrate the process of screening a fish species using FISK v2 in a realistic management scenario by assessing the Barcoo grunter Scortum barcoo (Terapontidae), a species whose management concerns are related to its potential use for aquaponics in Florida. The FISK v2 screening of Barcoo grunter placed the species into the lower range of medium risk (score = 5), suggesting it is a permissible species for use in Florida under current nonnative species regulations. Screening of the Barcoo grunter illustrates the usefulness of FISK v2 as a proactive tool serving to inform risk management decisions, but the low level of confidence associated with the assessment highlighted a dearth of critical information on this species. © 2012 Society for Risk Analysis.

Land use strategies to mitigate climate change in carbon dense temperate forests.

Science.gov (United States)

Law, Beverly E; Hudiburg, Tara W; Berner, Logan T; Kent, Jeffrey J; Buotte, Polly C; Harmon, Mark E

2018-04-03

Strategies to mitigate carbon dioxide emissions through forestry activities have been proposed, but ecosystem process-based integration of climate change, enhanced CO 2 , disturbance from fire, and management actions at regional scales are extremely limited. Here, we examine the relative merits of afforestation, reforestation, management changes, and harvest residue bioenergy use in the Pacific Northwest. This region represents some of the highest carbon density forests in the world, which can store carbon in trees for 800 y or more. Oregon's net ecosystem carbon balance (NECB) was equivalent to 72% of total emissions in 2011-2015. By 2100, simulations show increased net carbon uptake with little change in wildfires. Reforestation, afforestation, lengthened harvest cycles on private lands, and restricting harvest on public lands increase NECB 56% by 2100, with the latter two actions contributing the most. Resultant cobenefits included water availability and biodiversity, primarily from increased forest area, age, and species diversity. Converting 127,000 ha of irrigated grass crops to native forests could decrease irrigation demand by 233 billion m 3 ⋅y -1 Utilizing harvest residues for bioenergy production instead of leaving them in forests to decompose increased emissions in the short-term (50 y), reducing mitigation effectiveness. Increasing forest carbon on public lands reduced emissions compared with storage in wood products because the residence time is more than twice that of wood products. Hence, temperate forests with high carbon densities and lower vulnerability to mortality have substantial potential for reducing forest sector emissions. Our analysis framework provides a template for assessments in other temperate regions. Copyright © 2018 the Author(s). Published by PNAS.

Seroprevalence of Capripoxvirus infection in sheep and goats among different agro-climatic zones of Odisha, India.

Science.gov (United States)

Hota, Abhishek; Biswal, Sangram; Sahoo, Niranjana; Venkatesan, Gnanavel; Arya, Sargam; Kumar, Amit; Ramakrishnan, Muthannan Andavar; Pandey, Awadh Bihari; Rout, Manoranjan

2018-01-01

The study was undertaken to assess the prevalence of antibodies to Capripoxviruses among small ruminants of Odisha, India. A total of 500 random serum samples collected from 214 sheep and 286 goats across 10 agro-climatic zones of Odisha, were screened using whole virus antigen-based indirect ELISA for antibodies against Capripoxviruses. Results were analyzed by suitable statistical methods. Screening of 500 serum samples showed seropositivity of 8.88% and 31.47% in sheep and goats, respectively, for Capripoxviruses. The prevalence rate according to agro-climatic zone ranged from 0% (North Eastern coastal plain zone) to 48.57% (North central plateau zone) for goat pox, and 0% (Western undulating zone and North central plateau) to 22.22% (South Eastern ghat zone) for sheep pox. The difference in prevalence rates among the various agro-climatic zones was statistically significant (ppox and Dhenkanal (80%) for goat pox. The study revealed serological evidence of Capripoxvirus infection in sheep and goat populations in the study area, in the absence of vaccination. Systematic investigation, monitoring, and reporting of outbreaks are necessary to devise control strategies.

Microstructure and Mechanical Properties of Laser Clad and Post-cladding Tempered AISI H13 Tool Steel

Science.gov (United States)

Telasang, Gururaj; Dutta Majumdar, Jyotsna; Wasekar, Nitin; Padmanabham, G.; Manna, Indranil

2015-05-01

This study reports a detailed investigation of the microstructure and mechanical properties (wear resistance and tensile strength) of hardened and tempered AISI H13 tool steel substrate following laser cladding with AISI H13 tool steel powder in as-clad and after post-cladding conventional bulk isothermal tempering [at 823 K (550 °C) for 2 hours] heat treatment. Laser cladding was carried out on AISI H13 tool steel substrate using a 6 kW continuous wave diode laser coupled with fiber delivering an energy density of 133 J/mm2 and equipped with a co-axial powder feeding nozzle capable of feeding powder at the rate of 13.3 × 10-3 g/mm2. Laser clad zone comprises martensite, retained austenite, and carbides, and measures an average hardness of 600 to 650 VHN. Subsequent isothermal tempering converted the microstructure into one with tempered martensite and uniform dispersion of carbides with a hardness of 550 to 650 VHN. Interestingly, laser cladding introduced residual compressive stress of 670 ± 15 MPa, which reduces to 580 ± 20 MPa following isothermal tempering. Micro-tensile testing with specimens machined from the clad zone across or transverse to cladding direction showed high strength but failure in brittle mode. On the other hand, similar testing with samples sectioned from the clad zone parallel or longitudinal to the direction of laser cladding prior to and after post-cladding tempering recorded lower strength but ductile failure with 4.7 and 8 pct elongation, respectively. Wear resistance of the laser surface clad and post-cladding tempered samples (evaluated by fretting wear testing) registered superior performance as compared to that of conventional hardened and tempered AISI H13 tool steel.

Methane Ebullition in Temperate Hydropower Reservoirs and Implications for US Policy on Greenhouse Gas Emissions.

Science.gov (United States)

Miller, Benjamin L; Arntzen, Evan V; Goldman, Amy E; Richmond, Marshall C

2017-10-01

The United States is home to 2198 dams actively used for hydropower production. With the December 2015 consensus adoption of the United Nations Framework Convention on Climate Change Paris Agreement, it is important to accurately quantify anthropogenic greenhouse gas emissions. Methane ebullition, or methane bubbles originating from river or lake sediments, has been shown to account for nearly all methane emissions from tropical hydropower reservoirs to the atmosphere. However, distinct ebullitive methane fluxes have been studied in comparatively few temperate hydropower reservoirs globally. This study measures ebullitive and diffusive methane fluxes from two eastern Washington reservoirs, and synthesizes existing studies of methane ebullition in temperate, boreal, and tropical hydropower reservoirs. Ebullition comprises nearly all methane emissions (>97%) from this study's two eastern Washington hydropower reservoirs to the atmosphere. Summer methane ebullition from these reservoirs was higher than ebullition in six southeastern U.S. hydropower reservoirs, however it was similar to temperate reservoirs in other parts of the world. Our literature synthesis suggests that methane ebullition from temperate hydropower reservoirs can be seasonally elevated compared to tropical climates, however annual emissions are likely to be higher within tropical climates, emphasizing the possible range of methane ebullition fluxes and the need for the further study of temperate reservoirs. Possible future changes to the Intergovernmental Panel on Climate Change and UNFCCC guidelines for national greenhouse gas inventories highlights the need for accurate assessment of reservoir emissions.

Methane Ebullition in Temperate Hydropower Reservoirs and Implications for US Policy on Greenhouse Gas Emissions

Science.gov (United States)

Miller, Benjamin L.; Arntzen, Evan V.; Goldman, Amy E.; Richmond, Marshall C.

2017-10-01

The United States is home to 2198 dams actively used for hydropower production. With the December 2015 consensus adoption of the United Nations Framework Convention on Climate Change Paris Agreement, it is important to accurately quantify anthropogenic greenhouse gas emissions. Methane ebullition, or methane bubbles originating from river or lake sediments, has been shown to account for nearly all methane emissions from tropical hydropower reservoirs to the atmosphere. However, distinct ebullitive methane fluxes have been studied in comparatively few temperate hydropower reservoirs globally. This study measures ebullitive and diffusive methane fluxes from two eastern Washington reservoirs, and synthesizes existing studies of methane ebullition in temperate, boreal, and tropical hydropower reservoirs. Ebullition comprises nearly all methane emissions (>97%) from this study's two eastern Washington hydropower reservoirs to the atmosphere. Summer methane ebullition from these reservoirs was higher than ebullition in six southeastern U.S. hydropower reservoirs, however it was similar to temperate reservoirs in other parts of the world. Our literature synthesis suggests that methane ebullition from temperate hydropower reservoirs can be seasonally elevated compared to tropical climates, however annual emissions are likely to be higher within tropical climates, emphasizing the possible range of methane ebullition fluxes and the need for the further study of temperate reservoirs. Possible future changes to the Intergovernmental Panel on Climate Change and UNFCCC guidelines for national greenhouse gas inventories highlights the need for accurate assessment of reservoir emissions.

Northward migrating trees establish in treefall gaps at the northern limit of the temperate-boreal ecotone, Ontario, Canada.

Science.gov (United States)

Leithead, Mark D; Anand, Madhur; Silva, Lucas C R

2010-12-01

Climate change is expected to promote migration of species. In ecotones, areas of ecological tension, disturbances may provide opportunities for some migrating species to establish in otherwise competitive environments. The size of and time since disturbance may determine the establishment ability of these species. We investigated gap dynamics of an old-growth red pine (Pinus resinosa Sol. ex Aiton) forest in the Great Lakes-St. Lawrence forest in northern Ontario, Canada, a transition zone between temperate and boreal forest. We investigated the effects of gaps of different sizes and ages on tree species abundance and basal area. Our results show that tree species from the temperate forest further south, such as red maple (Acer rubrum L.), red oak (Quercus rubra L.), and white pine (Pinus strobus L.), establish more often in large, old gaps; however, tree species that have more northern distributions, such as black spruce (Picea mariana Mill.), paper birch (Betula papyrifera Marsh.), and red pine show no difference in establishment ability with gap size or age. These differences in composition could not be attributed to autogenic succession. We conclude that treefall gaps in this forest facilitate the establishment of northward migrating species, potentially providing a pathway for future forest migration in response to recent changes in climate.

Climate Change Impacts on the Mediterranean Coastal Zones

International Nuclear Information System (INIS)

Brochier, F.; Ramieri, E.

2001-04-01

The main objective of this paper is to highlight the potential impacts of changes in climatic conditions and in related variables, which could affect coastal areas, as well as to identify potential response measures which could reduce the vulnerability of coastal systems and enhance their adaptability. Attention will be focused on the Mediterranean basin which is in the climate change context, a zone of great interest and of recent concern at the world scale by some features: strong ocean-atmosphere-land interactions; contrast between the small size of the sea and its significant role in the global climate system; possibility to use it at a scaled down model for the monitoring of environmental and climate evolution; critical environmental conditions of some areas and high human pressure; and strong geographical, socio-economic and climatic contrasts. The first section provides an introduction to the climate change issue, the past trends and the projections of future climate at the global scale. The second section presents the main features of the Mediterranean basin and some relevant regional projections of future climatic variables. The third section focuses on the main likely impacts on the Mediterranean coasts. Different coastal systems - such as islands, deltas, estuaries, coastal wetlands and coastal cities - and different climate change impacts - such as inundation, increased flooding, salinisation, salt water intrusion, desertification, and increased erosion - are addressed in this section. Finally the last section brings some conclusions and identify some strategies of adaptations and directions for future research aimed at improving our ability to predict and assess the local impacts of climate change in the region

Mechanism of Secondary Hardening in Rapid Tempering of Dual-Phase Steel

Science.gov (United States)

Saha, Dulal Chandra; Nayak, Sashank S.; Biro, Elliot; Gerlich, Adrian P.; Zhou, Y.

2014-12-01

Dual-phase steel with ferrite-martensite-bainite microstructure exhibited secondary hardening in the subcritical heat affected zone during fiber laser welding. Rapid isothermal tempering conducted in a Gleeble simulator also indicated occurrence of secondary hardening at 773 K (500 °C), as confirmed by plotting the tempered hardness against the Holloman-Jaffe parameter. Isothermally tempered specimens were characterized by analytic transmission electron microscopy and high-angle annular dark-field imaging. The cementite (Fe3C) and TiC located in the bainite phase of DP steel decomposed upon rapid tempering to form needle-shaped Mo2C (aspect ratio ranging from 10 to 25) and plate-shaped M4C3 carbides giving rise to secondary hardening. Precipitation of these thermodynamically stable and coherent carbides promoted the hardening phenomenon. However, complex carbides were only seen in the tempered bainite and were not detected in the tempered martensite. The martensite phase decomposed into ferrite and spherical Fe3C, and interlath-retained austenite decomposed into ferrite and elongated carbide.

Relation of Chlorophyll Fluorescence Sensitive Reflectance Ratios to Carbon FluxMeasurements ofMontanne Grassland and Norway Spruce Forest Ecosystems in the Temperate Zone

Czech Academy of Sciences Publication Activity Database

Ač, Alexander; Malenovský, Z.; Urban, Otmar; Hanuš, Jan; Zitová, Martina; Navrátil, M.; Vráblová, M.; Olejníčková, Julie; Špunda, V.; Marek, Michal V.

2012-01-01

Roč. 2012, č. 2012 (2012), s. 1-13 ISSN 1537-744X R&D Projects: GA MŽP(CZ) SP/2D1/70/08; GA MŽP(CZ) SP/2D1/93/07; GA MŠk(CZ) LM2010007; GA MŠk(CZ) ED1.1.00/02.0073 Institutional research plan: CEZ:AV0Z60870520 Keywords : Chlorophyll fluorescence * carbon flux * forest ecosystems * Norway Spruce * temperate zone Subject RIV: EH - Ecology, Behaviour Impact factor: 1.730, year: 2012

Integration of climatic indices in an objective probabilistic model for establishing and mapping viticultural climatic zones in a region

Science.gov (United States)

Moral, Francisco J.; Rebollo, Francisco J.; Paniagua, Luis L.; García, Abelardo; Honorio, Fulgencio

2016-05-01

Different climatic indices have been proposed to determine the wine suitability in a region. Some of them are related to the air temperature, but the hydric component of climate should also be considered which, in turn, is influenced by the precipitation during the different stages of the grapevine growing and ripening periods. In this study, we propose using the information obtained from ten climatic indices [heliothermal index (HI), cool night index (CI), dryness index (DI), growing season temperature (GST), the Winkler index (WI), September mean thermal amplitude (MTA), annual precipitation (AP), precipitation during flowering (PDF), precipitation before flowering (PBF), and summer precipitation (SP)] as inputs in an objective and probabilistic model, the Rasch model, with the aim of integrating the individual effects of them, obtaining the climate data that summarize all main climatic indices, which could influence on wine suitability from a climate viewpoint, and utilizing the Rasch measures to generate homogeneous climatic zones. The use of the Rasch model to estimate viticultural climatic suitability constitutes a new application of great practical importance, enabling to rationally determine locations in a region where high viticultural potential exists and establishing a ranking of the climatic indices which exerts an important influence on wine suitability in a region. Furthermore, from the measures of viticultural climatic suitability at some locations, estimates can be computed using a geostatistical algorithm, and these estimates can be utilized to map viticultural climatic zones in a region. To illustrate the process, an application to Extremadura, southwestern Spain, is shown.

Hair coat properties of donkeys, mules and horses in a temperate climate.

Science.gov (United States)

Osthaus, B; Proops, L; Long, S; Bell, N; Hayday, K; Burden, F

2018-05-01

There are clear differences between donkeys and horses in their evolutionary history, physiology, behaviour and husbandry needs. Donkeys are often kept in climates that they are not adapted to and as such may suffer impaired welfare unless protection from the elements is provided. To compare some of the hair coat properties of donkeys, mules and horses living outside, throughout the year, in the temperate climate of the UK. Longitudinal study. Hair samples were taken from 42 animals: 18 donkeys (4 females, 14 males), 16 horses (6 females, 10 males) and eight mules (5 females, 3 males), in March, June, September and December. The weight, length and width of hair were measured, across the four seasons, as indicators of the hair coat insulation properties. Donkeys' hair coats do not significantly differ across the seasons. All three measurements of the insulation properties of the hair samples indicate that donkeys do not grow a winter coat and that their hair coat was significantly lighter, shorter and thinner than that of horses and mules in winter. In contrast, the hair coats of horses changed significantly between seasons, growing thicker in winter. The measurements cover only a limited range of features that contribute to the thermoregulation of an animal. Further research is needed to assess shelter preferences by behavioural measures, and absolute heat loss via thermoimaging. Donkeys, and to a lesser extent mules, appear not to be as adapted to colder, wet climates as horses, and may therefore require additional protection from the elements, such as access to a wind and waterproof shelter, in order for their welfare needs to be met. © 2017 The Authors. Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.

Impact of mild heat stress on dry matter intake, milk yield and milk composition in mid-lactation Holstein dairy cows in a temperate climate.

Science.gov (United States)

Gorniak, Tobias; Meyer, Ulrich; Südekum, Karl-Heinz; Dänicke, Sven

2014-01-01

The aim of the present study was to evaluate the impact of summer temperatures in a temperate climate on mid-lactation Holstein dairy cows. Therefore, a data set was examined comprising five trials with dairy cows conducted at the experimental station of the Friedrich-Loeffler-Institute in Braunschweig, Germany. The temperature-humidity index (THI) was calculated using temperature and humidity data from the barns recorded between January 2010 and July 2012. By using a generalised additive mixed model, the impact of increasing THI on dry matter intake, milk yield and milk composition was evaluated. Dry matter intake and milk yield decreased when THI rose above 60, whilst water intake increased in a linear manner beyond THI 30. Furthermore, milk protein and milk fat content decreased continuously with increasing THI. The present results revealed that heat stress exists in Lower Saxony, Germany. However, further research is necessary to describe the mode of action of heat stress. Especially, mild heat stress has to be investigated in more detail and appropriate heat stress thresholds for temperate climates have to be developed.

Teaching climate science within the transdisciplinary framework of Critical Zone science

Science.gov (United States)

White, T. S.; Wymore, A.; Dere, A. L. D.; Washburne, J. C.; Hoffman, A.; Conklin, M. H.

2017-12-01

During the past decade a new realm of Earth surface and environmental science has evolved, Critical Zone (CZ) science. The CZ is the outermost layer of the continents spanning from the top of the vegetation canopy down to the bottom of the fresh groundwater zone. CZ science integrates across many disciplines and cross cutting concepts, including climate science, and much progress has been made by the CZ community to develop educational curricula - descriptions of the climate science aspects of two of those follows. An interdisciplinary team of CZ scientists developed an undergraduate course entitled "Introduction to CZ science". The semester-long course is modular, has been tested in multiple university settings, and the content is available online. A primary tenet of the course is that to achieve environmental sustainability, society must understand the CZ system, the natural processes and services of the CZ that are of value to society, and how those processes operate with and without the presence of humanity. A fundamental concept in the course is that the fluxes of water, C, energy, reactive gases, particulates and nutrients throughout the CZ are directly and indirectly related to climatic phenomenon and processes. Units on land-atmosphere interactions, weathering, and water budgets highlight the connection between CZ science and climate science, and are augmented by learning activities that consider climate links to soil development and landscape evolution. An online open-source course entitled "Earth 530: Earth Surface Processes in the Critical Zone'" is offered as part of The Pennsylvania State University's Masters of Education in Earth Sciences program. The course is designed to educate teachers interested in incorporating CZ science into their classrooms, though it is usable by anyone with a basic understanding of Earth surface and environmental science. Earth 530 introduces students to knowledge needed to understand the CZ through integration of

Effect of climate warming on the annual terrestrial net ecosystem CO2 exchange globally in the boreal and temperate regions.

Science.gov (United States)

Zhang, Zhiyuan; Zhang, Renduo; Cescatti, Alessandro; Wohlfahrt, Georg; Buchmann, Nina; Zhu, Juan; Chen, Guanhong; Moyano, Fernando; Pumpanen, Jukka; Hirano, Takashi; Takagi, Kentaro; Merbold, Lutz

2017-06-08

The net ecosystem CO 2 exchange is the result of the imbalance between the assimilation process (gross primary production, GPP) and ecosystem respiration (RE). The aim of this study was to investigate temperature sensitivities of these processes and the effect of climate warming on the annual terrestrial net ecosystem CO 2 exchange globally in the boreal and temperate regions. A database of 403 site-years of ecosystem flux data at 101 sites in the world was collected and analyzed. Temperature sensitivities of rates of RE and GPP were quantified with Q 10 , defined as the increase of RE (or GPP) rates with a temperature rise of 10 °C. Results showed that on the annual time scale, the intrinsic temperature sensitivity of GPP (Q 10sG ) was higher than or equivalent to the intrinsic temperature sensitivity of RE (Q 10sR ). Q 10sG was negatively correlated to the mean annual temperature (MAT), whereas Q 10sR was independent of MAT. The analysis of the current temperature sensitivities and net ecosystem production suggested that temperature rise might enhance the CO 2 sink of terrestrial ecosystems both in the boreal and temperate regions. In addition, ecosystems in these regions with different plant functional types should sequester more CO 2 with climate warming.

Prey type and foraging ecology of Sanderlings Calidris alba in different climate zones: are tropical areas more favourable than temperate sites?

Directory of Open Access Journals (Sweden)

Kirsten Grond

2015-08-01

Full Text Available Sanderlings (Calidris alba are long-distance migratory shorebirds with a non-breeding range that spans temperate and tropical coastal habitats. Breeding in the High Arctic combined with non-breeding seasons in the tropics necessitate long migrations, which are energetically demanding. On an annual basis, the higher energy expenditures during migration might pay off if food availability in the tropics is higher than at temperate latitudes. We compared foraging behaviour of birds at a north temperate and a tropical non-breeding site in the Netherlands and Ghana, respectively. In both cases the birds used similar habitats (open beaches, and experienced similar periods of daylight, which enabled us to compare food abundance and availability, and behavioural time budgets and food intake. During the non-breeding season, Sanderlings in the Netherlands spent 79% of their day foraging; in Ghana birds spent only 38% of the daytime period foraging and the largest proportion of their time resting (58%. The main prey item in the Netherlands was the soft-bodied polychaete Scolelepis squamata, while Sanderlings in Ghana fed almost exclusively on the bivalve Donax pulchellus, which they swallowed whole and crushed internally. Average availability of polychaete worms in the Netherlands was 7.4 g ash free dry mass (AFDM m−2, which was one tenth of the 77.1 g AFDM m−2 estimated for the beach in Ghana. In the tropical environment of Ghana the Sanderlings combined relatively low energy requirements with high prey intake rates (1.64 mg opposed to 0.13 mg AFDM s−1 for Ghana and the Netherlands respectively. Although this may suggest that the Ghana beaches are the most favourable environment, processing the hard-shelled bivalve (D. pulchellus which is the staple food could be costly. The large amount of daytime spent resting in Ghana may be indicative of the time needed to process the shell fragments, rather than indicate rest.

Seroprevalence of Capripoxvirus infection in sheep and goats among different agro-climatic zones of Odisha, India

Directory of Open Access Journals (Sweden)

Abhishek Hota

2018-01-01

Full Text Available Aim: The study was undertaken to assess the prevalence of antibodies to Capripoxviruses among small ruminants of Odisha, India. Materials and Methods: A total of 500 random serum samples collected from 214 sheep and 286 goats across 10 agro-climatic zones of Odisha, were screened using whole virus antigen-based indirect ELISA for antibodies against Capripoxviruses. Results were analyzed by suitable statistical methods. Results: Screening of 500 serum samples showed seropositivity of 8.88% and 31.47% in sheep and goats, respectively, for Capripoxviruses. The prevalence rate according to agro-climatic zone ranged from 0% (North Eastern coastal plain zone to 48.57% (North central plateau zone for goat pox, and 0% (Western undulating zone and North central plateau to 22.22% (South Eastern ghat zone for sheep pox. The difference in prevalence rates among the various agro-climatic zones was statistically significant (p<0.05 for goats, but not for sheep. Antibody prevalence rates among various districts were recorded to be the highest in Jagatsinghpur (30% for sheep pox and Dhenkanal (80% for goat pox. Conclusion: The study revealed serological evidence of Capripoxvirus infection in sheep and goat populations in the study area, in the absence of vaccination. Systematic investigation, monitoring, and reporting of outbreaks are necessary to devise control strategies.

Urban local climate zone mapping and apply in urban environment study

Science.gov (United States)

He, Shan; Zhang, Yunwei; Zhang, Jili

2018-02-01

The city’s local climate zone (LCZ) was considered to be a powerful tool for urban climate mapping. But for cities in different countries and regions, the LCZ division methods and results were different, thus targeted researches should be performed. In the current work, a LCZ mapping method was proposed, which is convenient in operation and city planning oriented. In this proposed method, the local climate zoning types were adjusted firstly, according to the characteristics of Chinese city, that more tall buildings and high density. Then the classification method proposed by WUDAPT based on remote sensing data was performed on Xi’an city, as an example, for LCZ mapping. Combined with the city road network, a reasonable expression of the dividing results was provided, to adapt to the characteristics in city planning that land parcels are usually recognized as the basic unit. The proposed method was validated against the actual land use and construction data that surveyed in Xi’an, with results indicating the feasibility of the proposed method for urban LCZ mapping in China.

Urban field classification by "local climate zones" in a medium-sized Central European city: the case of Olomouc (Czech Republic)

Science.gov (United States)

Lehnert, Michal; Geletič, Jan; Husák, Jan; Vysoudil, Miroslav

2015-11-01

The stations of the Metropolitan Station Network in Olomouc (Czech Republic) were assigned to local climatic zones, and the temperature characteristics of the stations were compared. The classification of local climatic zones represents an up-to-date concept for the unification of the characterization of the neighborhoods of climate research sites. This study is one of the first to provide a classification of existing stations within local climate zones. Using a combination of GIS-based analyses and field research, the values of geometric and surface cover properties were calculated, and the stations were subsequently classified into the local climate zones. It turned out that the classification of local climatic zones can be efficiently used for representative documentation of the neighborhood of the climate stations. To achieve a full standardization of the description of the neighborhood of a station, the classification procedures, including the methods used for the processing of spatial data and methods used for the indication of specific local characteristics, must be also standardized. Although the main patterns of temperature differences between the stations with a compact rise, those with an open rise and the stations with no rise or sparsely built areas were evident; the air temperature also showed considerable differences within particular zones. These differences were largely caused by various geometric layout of development and by unstandardized placement of the stations. For the direct comparison of temperatures between zones, particularly those stations which have been placed in such a way that they are as representative as possible for the zone in question should be used in further research.

Tempered fractional calculus

Energy Technology Data Exchange (ETDEWEB)

Sabzikar, Farzad, E-mail: sabzika2@stt.msu.edu [Department of Statistics and Probability, Michigan State University, East Lansing, MI 48823 (United States); Meerschaert, Mark M., E-mail: mcubed@stt.msu.edu [Department of Statistics and Probability, Michigan State University, East Lansing, MI 48823 (United States); Chen, Jinghua, E-mail: cjhdzdz@163.com [School of Sciences, Jimei University, Xiamen, Fujian, 361021 (China)

2015-07-15

Fractional derivatives and integrals are convolutions with a power law. Multiplying by an exponential factor leads to tempered fractional derivatives and integrals. Tempered fractional diffusion equations, where the usual second derivative in space is replaced by a tempered fractional derivative, govern the limits of random walk models with an exponentially tempered power law jump distribution. The limiting tempered stable probability densities exhibit semi-heavy tails, which are commonly observed in finance. Tempered power law waiting times lead to tempered fractional time derivatives, which have proven useful in geophysics. The tempered fractional derivative or integral of a Brownian motion, called a tempered fractional Brownian motion, can exhibit semi-long range dependence. The increments of this process, called tempered fractional Gaussian noise, provide a useful new stochastic model for wind speed data. A tempered fractional difference forms the basis for numerical methods to solve tempered fractional diffusion equations, and it also provides a useful new correlation model in time series.

Tempered fractional calculus

Science.gov (United States)

Sabzikar, Farzad; Meerschaert, Mark M.; Chen, Jinghua

2015-07-01

Fractional derivatives and integrals are convolutions with a power law. Multiplying by an exponential factor leads to tempered fractional derivatives and integrals. Tempered fractional diffusion equations, where the usual second derivative in space is replaced by a tempered fractional derivative, govern the limits of random walk models with an exponentially tempered power law jump distribution. The limiting tempered stable probability densities exhibit semi-heavy tails, which are commonly observed in finance. Tempered power law waiting times lead to tempered fractional time derivatives, which have proven useful in geophysics. The tempered fractional derivative or integral of a Brownian motion, called a tempered fractional Brownian motion, can exhibit semi-long range dependence. The increments of this process, called tempered fractional Gaussian noise, provide a useful new stochastic model for wind speed data. A tempered fractional difference forms the basis for numerical methods to solve tempered fractional diffusion equations, and it also provides a useful new correlation model in time series.

Tempered fractional calculus

International Nuclear Information System (INIS)

Sabzikar, Farzad; Meerschaert, Mark M.; Chen, Jinghua

2015-01-01

Fractional derivatives and integrals are convolutions with a power law. Multiplying by an exponential factor leads to tempered fractional derivatives and integrals. Tempered fractional diffusion equations, where the usual second derivative in space is replaced by a tempered fractional derivative, govern the limits of random walk models with an exponentially tempered power law jump distribution. The limiting tempered stable probability densities exhibit semi-heavy tails, which are commonly observed in finance. Tempered power law waiting times lead to tempered fractional time derivatives, which have proven useful in geophysics. The tempered fractional derivative or integral of a Brownian motion, called a tempered fractional Brownian motion, can exhibit semi-long range dependence. The increments of this process, called tempered fractional Gaussian noise, provide a useful new stochastic model for wind speed data. A tempered fractional difference forms the basis for numerical methods to solve tempered fractional diffusion equations, and it also provides a useful new correlation model in time series

Ocean cleaning stations under a changing climate: biological responses of tropical and temperate fish-cleaner shrimp to global warming.

Science.gov (United States)

Rosa, Rui; Lopes, Ana Rita; Pimentel, Marta; Faleiro, Filipa; Baptista, Miguel; Trübenbach, Katja; Narciso, Luis; Dionísio, Gisela; Pegado, Maria Rita; Repolho, Tiago; Calado, Ricardo; Diniz, Mário

2014-10-01

Cleaning symbioses play an important role in the health of certain coastal marine communities. These interspecific associations often occur at specific sites (cleaning stations) where a cleaner organism (commonly a fish or shrimp) removes ectoparasites/damaged tissue from a 'client' (a larger cooperating fish). At present, the potential impact of climate change on the fitness of cleaner organisms remains unknown. This study investigated the physiological and biochemical responses of tropical (Lysmata amboinensis) and temperate (L. seticaudata) cleaner shrimp to global warming. Specifically, thermal limits (CTMax), metabolic rates, thermal sensitivity, heat shock response (HSR), lipid peroxidation [malondialdehyde (MDA) concentration], lactate levels, antioxidant (GST, SOD and catalase) and digestive enzyme activities (trypsin and alkaline phosphatase) at current and warming (+3 °C) temperature conditions. In contrast to the temperate species, CTMax values decreased significantly from current (24-27 °C) to warming temperature conditions (30 °C) for the tropical shrimp, where metabolic thermal sensitivity was affected and the HSR was significantly reduced. MDA levels in tropical shrimp increased dramatically, indicating extreme cellular lipid peroxidation, which was not observed in the temperate shrimp. Lactate levels, GST and SOD activities were significantly enhanced within the muscle tissue of the tropical species. Digestive enzyme activities in the hepatopancreas of both species were significantly decreased by warmer temperatures. Our data suggest that the tropical cleaner shrimp will be more vulnerable to global warming than the temperate Lysmata seticaudata; the latter evolved in a relatively unstable environment with seasonal thermal variations that may have conferred greater adaptive plasticity. Thus, tropical cleaning symbioses may be challenged at a greater degree by warming-related anthropogenic forcing, with potential cascading effects on the health

Does climate undermine subjective well-being? A 58-nation study

NARCIS (Netherlands)

Fischer, Ronald; Van de Vliert, Evert

The authors test predictions from climato-economic theories of culture that climate and wealth interact in their influence on psychological processes. Demanding climates (defined as colder than temperate and hotter than temperate climates) create potential threats for humans. If these demands can be

Riparian buffer zones as pesticide filters of no-till crops.

Science.gov (United States)

Aguiar, Terencio R; Bortolozo, F R; Hansel, F A; Rasera, K; Ferreira, M T

2015-07-01

Several studies have pointed to the potential benefits of riparian vegetation as buffer zones for agricultural and industrial pollutants harmful to aquatic ecosystems. However, other studies have called into question its use as an ecological filter, questioning the widths and conditions for which they are effective as a filter. In this work, we have investigated the buffering capacity of the riparian one to retain pesticides in the water-saturated zone, on 27 sites composed by riparian buffer zones with different vegetation structure (woody, shrubs, or grass vegetation) and width (12, 36, and 60 m). Five pesticides were analyzed. The effectiveness of the filtering was largely influenced by the width and vegetation type of the buffer zone. In general, decreasing pesticide removal followed in this order wood > shrubs > grass. The 60 m woody buffer zone was the most effective in the removal of all the pesticides. Only atrazine was detected in this case (0.3 μg L(-1)). Furthermore, a linear correlation (R (2) > 0.97) was observed in their removal for all compounds and buffer zones studied. Thus, preserving the woody vegetation in the riparian zone is important for watershed management and groundwater quality in the no-tillage system in temperate climate.

Forests tend to cool the land surface in the temperate zone: An analysis of the mechanisms controlling radiometric surface temperature change in managed temperate ecosystems

Science.gov (United States)

Stoy, P. C.; Katul, G. G.; Juang, J.; Siqueira, M. B.; Novick, K. A.; Essery, R.; Dore, S.; Kolb, T. E.; Montes-Helu, M. C.; Scott, R. L.

2010-12-01

Vegetation is an important control on the surface energy balance and thereby surface temperature. Boreal forests and arctic shrubs are thought to warm the land surface by absorbing more radiation than the vegetation they replace. The surface temperatures of tropical forests tend to be cooler than deforested landscapes due to enhanced evapotranspiration. The effects of reforestation on surface temperature change in the temperate zone is less-certain, but recent modeling efforts suggest forests have a global warming effect. We quantified the mechanisms driving radiometric surface changes following landcover changes using paired ecosystem case studies from the Ameriflux database with energy balance models of varying complexity. Results confirm previous findings that deciduous and coniferous forests in the southeastern U.S. are ca. 1 °C cooler than an adjacent field on an annual basis because aerodynamic/ecophysiological cooling of 2-3 °C outweighs an albedo-related warming of stand-replacing ponderosa pine fire was ca. 1 °C warmer than unburned stands because a 1.5 °C aerodynamic warming offset a slight surface cooling due to greater albedo and soil heat flux. An ecosystem dominated by mesquite shrub encroachment was nearly 2 °C warmer than a native grassland ecosystem as aerodynamic and albedo-related warming outweighed a small cooling effect due to changes in soil heat flux. The forested ecosystems in these case studies are documented to have higher carbon uptake than the non-forested systems. Results suggest that temperate forests tend to cool the land surface and suggest that previous model-based findings that forests warm the Earth’s surface globally should be reconsidered.Changes to radiometric surface temperature (K) following changes in vegetation using paired ecosystem case studies C4 grassland and shrub ecosystem surface temperatures were adjusted for differences in air temperature across sites.

The CARMENES Search for Exoplanets around M Dwarfs: A Low-mass Planet in the Temperate Zone of the Nearby K2-18

Science.gov (United States)

Sarkis, Paula; Henning, Thomas; Kürster, Martin; Trifonov, Trifon; Zechmeister, Mathias; Tal-Or, Lev; Anglada-Escudé, Guillem; Hatzes, Artie P.; Lafarga, Marina; Dreizler, Stefan; Ribas, Ignasi; Caballero, José A.; Reiners, Ansgar; Mallonn, Matthias; Morales, Juan C.; Kaminski, Adrian; Aceituno, Jesús; Amado, Pedro J.; Béjar, Victor J. S.; Hagen, Hans-Jürgen; Jeffers, Sandra; Quirrenbach, Andreas; Launhardt, Ralf; Marvin, Christopher; Montes, David

2018-06-01

K2-18 is a nearby M2.5 dwarf, located at 34 pc and hosting a transiting planet that was first discovered by the K2 mission and later confirmed with Spitzer Space Telescope observations. With a radius of ∼2 R ⊕ and an orbital period of ∼33 days, the planet lies in the temperate zone of its host star and receives stellar irradiation similar to that of Earth. Here we perform radial velocity follow-up observations with the visual channel of CARMENES with the goal of determining the mass and density of the planet. We measure a planetary semi-amplitude of K b ∼ 3.5 {{m}} {{{s}}}-1 and a mass of M b ∼ 9 M ⊕, yielding a bulk density around {ρ }b∼ 4 {{g}} {cm}}-3. This indicates a low-mass planet with a composition consistent with a solid core and a volatile-rich envelope. A signal at 9 days was recently reported using radial velocity measurements taken with the HARPS spectrograph. This was interpreted as being due to a second planet. We see a weaker, time- and wavelength-dependent signal in the CARMENES data set and thus favor stellar activity for its origin. K2-18 b joins the growing group of low-mass planets detected in the temperate zone of M dwarfs. The brightness of the host star in the near-infrared makes the system a good target for detailed atmospheric studies with the James Webb Space Telescope.

Predicting impacts of climate change on the aboveground carbon sequestration rate of a temperate forest in northeastern China.

Science.gov (United States)

Ma, Jun; Hu, Yuanman; Bu, Rencang; Chang, Yu; Deng, Huawei; Qin, Qin

2014-01-01

The aboveground carbon sequestration rate (ACSR) reflects the influence of climate change on forest dynamics. To reveal the long-term effects of climate change on forest succession and carbon sequestration, a forest landscape succession and disturbance model (LANDIS Pro7.0) was used to simulate the ACSR of a temperate forest at the community and species levels in northeastern China based on both current and predicted climatic data. On the community level, the ACSR of mixed Korean pine hardwood forests and mixed larch hardwood forests, fluctuated during the entire simulation, while a large decline of ACSR emerged in interim of simulation in spruce-fir forest and aspen-white birch forests, respectively. On the species level, the ACSR of all conifers declined greatly around 2070s except for Korean pine. The ACSR of dominant hardwoods in the Lesser Khingan Mountains area, such as Manchurian ash, Amur cork, black elm, and ribbed birch fluctuated with broad ranges, respectively. Pioneer species experienced a sharp decline around 2080s, and they would finally disappear in the simulation. The differences of the ACSR among various climates were mainly identified in mixed Korean pine hardwood forests, in all conifers, and in a few hardwoods in the last quarter of simulation. These results indicate that climate warming can influence the ACSR in the Lesser Khingan Mountains area, and the largest impact commonly emerged in the A2 scenario. The ACSR of coniferous species experienced higher impact by climate change than that of deciduous species.

Effects of Environmental Factors on the Disinfection Performance of a Wastewater Stabilization Pond Operated in a Temperate Climate

Directory of Open Access Journals (Sweden)

Lei Liu

2015-12-01

Full Text Available Treatment in a wastewater stabilization pond (WSP relies on natural purification processes, which can be sensitive to both location and climate. This study investigated the effects of three environmental factors, pH, dissolved oxygen (DO and temperature, on disinfection efficiency in a WSP system consisting of three facultative cells, and operated in a temperate climate region, in Eastern Ontario, Canada. Indicator organism (Escherichia coli (E. coli removal in WSP systems is driven by a combination of different factors. Elevated pH and DO concentrations, which are attributed to the presence of algae, are important factors for effective disinfection. Therefore, the presence of algae in natural wastewater treatment systems can contribute appreciably to disinfection. Consequently, based on algal concentrations, removal efficiencies of pathogenic microorganisms during wastewater treatment over the course of a year can be highly variable, where higher removal efficiencies would be expected in summer and fall seasons.

Fish but Not Macroinvertebrates Promote Trophic Cascading Effects in High Density Submersed Plant Experimental Lake Food Webs in Two Contrasting Climate Regions

Directory of Open Access Journals (Sweden)

Carlos Iglesias

2017-07-01

Full Text Available Predators play a key role in the functioning of shallow lakes. Differences between the response of temperate and subtropical systems to fish predation have been proposed, but experimental evidence is scarce. To elucidate cascading effects produced by predators in contrasting climatic zones, we conducted a mesocosm experiment in three pairs of lakes in Uruguay and Denmark. We used two typical planktivorous-omnivorous fish species (Jenynsia multidentata + Cnesterodon decemmaculatus and Gasterosteus aculeatus + Perca fluviatilis and one littoral omnivorous-predatory macroinvertebrate (Palaemonetes argentinus and Gammarus lacustris, alone and combined, in numbers resembling natural densities. Fish predation on zooplankton increased phytoplankton biomass in both climate zones, whereas the effects of predatory macroinvertebrates on zooplankton and phytoplankton were not significant in either climate zone. Macroinvertebrates (that freely colonized the sampling devices were diminished by fish in both climate areas; however, periphyton biomass did not vary among treatments. Our experiments demonstrated that fish affected the structure of both planktonic and littoral herbivorous communities in both climate regions, with a visible positive cascading effect on phytoplankton biomass, but no effects on periphyton. Altogether, fish impacts appeared to be a strong driver of turbid water conditions in shallow lakes regardless of climatic zone by indirectly contributing to increasing phytoplankton biomass.

A guideline for sizing Photovoltaic panels across different climatic zones in Burkina Faso

International Nuclear Information System (INIS)

Waongo, M; Koalaga, Z; Zougmore, F

2012-01-01

In many developing countries a long time series of solar radiation measurements are not often available. This is due to the cost, maintenance and calibration requirements of measuring devices. Consequently, the use of solar energy by Photovoltaic (PV) conversion copes with the choice and the optimization of the PV system. This work concerned the analysis of climate parameters strongly influencing the Photovoltaic (PV) systems energy production and the simulation of an ideal system based on a single PV module. Estimation and analysis of time series of climate parameters covered a set of six weather stations with respect to the three climatic zones in Burkina Faso (BF), over 38 years. The analysis showed that the solar irradiation in BF lies between 3 kWh/m 2 /day and 7.5 kWh/m 2 /day. The highest values of the solar irradiation are measured in the Northern part of the country while lowest values are measured in the Southern part. Daily mean temperature for all weather stations was greater than the Standard Test Condition (STC) temperature (25°C) over a long period of the year. Information on solar irradiation and temperature is fundamental for PV systems sizing process. For PV performance evaluation, a simulation is carried out using an ideal system composed of a single PV module from TENESOL Company. This simulation is performed for three classes of climatic conditions 'Mean situation', 'Adverse situation', and 'Beneficial situation', and evaluated for six sitesacross BF. The results revealed intra-annual and spatial variability of Maximum Power (MP). Across BF, MP varied between 60 W/day and 190 W/day in Sahelian zone, between 65 W/day and 185 W/day in soudano-sahelian zone, and between 67 W/day and 208 W/day in Soudanian zone. MP intra-annual variability is higher during the period July-August, mainly for 'Beneficial situation'. The negative effect of temperature on PV energy production is specially amplified in Sahelian zone due to its highest temperatures

Impact of global warming on the geobotanic zones: an experiment with a statistical-dynamical climate model

Energy Technology Data Exchange (ETDEWEB)

Franchito, Sergio H.; Brahmananda Rao, V. [Instituto Nacional de Pesquisas Espaciais, Centro de Ciencia do Sistema Terrestre, CCST, Sau Paulo, SP (Brazil); Moraes, E.C. [Instituto Nacional de Pesquisas Espaciais, Divisao de Sensoriamento Remoto, DSR, Sau Paulo, SP (Brazil)

2011-11-15

In this study, a zonally-averaged statistical climate model (SDM) is used to investigate the impact of global warming on the distribution of the geobotanic zones over the globe. The model includes a parameterization of the biogeophysical feedback mechanism that links the state of surface to the atmosphere (a bidirectional interaction between vegetation and climate). In the control experiment (simulation of the present-day climate) the geobotanic state is well simulated by the model, so that the distribution of the geobotanic zones over the globe shows a very good agreement with the observed ones. The impact of global warming on the distribution of the geobotanic zones is investigated considering the increase of CO{sub 2} concentration for the B1, A2 and A1FI scenarios. The results showed that the geobotanic zones over the entire earth can be modified in future due to global warming. Expansion of subtropical desert and semi-desert zones in the Northern and Southern Hemispheres, retreat of glaciers and sea-ice, with the Arctic region being particularly affected and a reduction of the tropical rainforest and boreal forest can occur due to the increase of the greenhouse gases concentration. The effects were more pronounced in the A1FI and A2 scenarios compared with the B1 scenario. The SDM results confirm IPCC AR4 projections of future climate and are consistent with simulations of more complex GCMs, reinforcing the necessity of the mitigation of climate change associated to global warming. (orig.)

Northward shift of the agricultural climate zone under 21st-century global climate change.

Science.gov (United States)

King, Myron; Altdorff, Daniel; Li, Pengfei; Galagedara, Lakshman; Holden, Joseph; Unc, Adrian

2018-05-21

As agricultural regions are threatened by climate change, warming of high latitude regions and increasing food demands may lead to northward expansion of global agriculture. While socio-economic demands and edaphic conditions may govern the expansion, climate is a key limiting factor. Extant literature on future crop projections considers established agricultural regions and is mainly temperature based. We employed growing degree days (GDD), as the physiological link between temperature and crop growth, to assess the global northward shift of agricultural climate zones under 21 st -century climate change. Using ClimGen scenarios for seven global climate models (GCMs), based on greenhouse gas (GHG) emissions and transient GHGs, we delineated the future extent of GDD areas, feasible for small cereals, and assessed the projected changes in rainfall and potential evapotranspiration. By 2099, roughly 76% (55% to 89%) of the boreal region might reach crop feasible GDD conditions, compared to the current 32%. The leading edge of the feasible GDD will shift northwards up to 1200 km by 2099 while the altitudinal shift remains marginal. However, most of the newly gained areas are associated with highly seasonal and monthly variations in climatic water balances, a critical component of any future land-use and management decisions.

Climate change-induced vegetation shifts lead to more ecological droughts despite projected rainfall increases in many global temperate drylands.

Science.gov (United States)

Tietjen, Britta; Schlaepfer, Daniel R; Bradford, John B; Lauenroth, William K; Hall, Sonia A; Duniway, Michael C; Hochstrasser, Tamara; Jia, Gensuo; Munson, Seth M; Pyke, David A; Wilson, Scott D

2017-07-01

Drylands occur worldwide and are particularly vulnerable to climate change because dryland ecosystems depend directly on soil water availability that may become increasingly limited as temperatures rise. Climate change will both directly impact soil water availability and change plant biomass, with resulting indirect feedbacks on soil moisture. Thus, the net impact of direct and indirect climate change effects on soil moisture requires better understanding. We used the ecohydrological simulation model SOILWAT at sites from temperate dryland ecosystems around the globe to disentangle the contributions of direct climate change effects and of additional indirect, climate change-induced changes in vegetation on soil water availability. We simulated current and future climate conditions projected by 16 GCMs under RCP 4.5 and RCP 8.5 for the end of the century. We determined shifts in water availability due to climate change alone and due to combined changes of climate and the growth form and biomass of vegetation. Vegetation change will mostly exacerbate low soil water availability in regions already expected to suffer from negative direct impacts of climate change (with the two RCP scenarios giving us qualitatively similar effects). By contrast, in regions that will likely experience increased water availability due to climate change alone, vegetation changes will counteract these increases due to increased water losses by interception. In only a small minority of locations, climate change-induced vegetation changes may lead to a net increase in water availability. These results suggest that changes in vegetation in response to climate change may exacerbate drought conditions and may dampen the effects of increased precipitation, that is, leading to more ecological droughts despite higher precipitation in some regions. Our results underscore the value of considering indirect effects of climate change on vegetation when assessing future soil moisture conditions in water

Climate change-induced vegetation shifts lead to more ecological droughts despite projected rainfall increases in many global temperate drylands

Science.gov (United States)

Tietjen, Britta; Schlaepfer, Daniel R.; Bradford, John B.; Laurenroth, William K.; Hall, Sonia A.; Duniway, Michael C.; Hochstrasser, Tamara; Jia, Gensuo; Munson, Seth M.; Pyke, David A.; Wilson, Scott D.

2017-01-01

Drylands occur world-wide and are particularly vulnerable to climate change since dryland ecosystems depend directly on soil water availability that may become increasingly limited as temperatures rise. Climate change will both directly impact soil water availability, and also change plant biomass, with resulting indirect feedbacks on soil moisture. Thus, the net impact of direct and indirect climate change effects on soil moisture requires better understanding.We used the ecohydrological simulation model SOILWAT at sites from temperate dryland ecosystems around the globe to disentangle the contributions of direct climate change effects and of additional indirect, climate change-induced changes in vegetation on soil water availability. We simulated current and future climate conditions projected by 16 GCMs under RCP 4.5 and RCP 8.5 for the end of the century. We determined shifts in water availability due to climate change alone and due to combined changes of climate and the growth form and biomass of vegetation.Vegetation change will mostly exacerbate low soil water availability in regions already expected to suffer from negative direct impacts of climate change (with the two RCP scenarios giving us qualitatively similar effects). By contrast, in regions that will likely experience increased water availability due to climate change alone, vegetation changes will counteract these increases due to increased water losses by interception. In only a small minority of locations, climate change induced vegetation changes may lead to a net increase in water availability. These results suggest that changes in vegetation in response to climate change may exacerbate drought conditions and may dampen the effects of increased precipitation, i.e. leading to more ecological droughts despite higher precipitation in some regions. Our results underscore the value of considering indirect effects of climate change on vegetation when assessing future soil moisture conditions in water

Effects of brood pheromone (SuperBoost) on consumption of protein supplement and growth of honey bee (Hymenoptera: Apidae) colonies during fall in a northern temperate climate.

Science.gov (United States)

Sagili, Ramesh R; Breece, Carolyn R

2012-08-01

Honey bee, Apis mellifera L. (Hymenoptera: Apidae), nutrition is vital for colony growth and maintenance of a robust immune system. Brood rearing in honey bee colonies is highly dependent on protein availability. Beekeepers in general provide protein supplement to colonies during periods of pollen dearth. Honey bee brood pheromone is a blend of methyl and ethyl fatty acid esters extractable from cuticle of honey bee larvae that communicates the presence of larvae in a colony. Honey bee brood pheromone has been shown to increase protein supplement consumption and growth of honey bee colonies in a subtropical winter climate. Here, we tested the hypothesis that synthetic brood pheromone (SuperBoost) has the potential to increase protein supplement consumption during fall in a temperate climate and thus increase colony growth. The experiments were conducted in two locations in Oregon during September and October 2009. In both the experiments, colonies receiving brood pheromone treatment consumed significantly higher protein supplement and had greater brood area and adult bees than controls. Results from this study suggest that synthetic brood pheromone may be used to stimulate honey bee colony growth by stimulating protein supplement consumption during fall in a northern temperate climate, when majority of the beekeepers feed protein supplement to their colonies.

Internal strains after recovery of hardness in tempered martensitic steels for fusion reactors

Science.gov (United States)

Brunelli, L.; Gondi, P.; Montanari, R.; Coppola, R.

1991-03-01

After tempering, with recovery of hardness, MANET steels present internal strains; these residual strains increase with quenching rate prior to tempering, and they remain after prolonged tempering times. On account of their persistence, after thermal treatments which lead to low dislocation and sub-boundary densities, the possibility has been considered that the high swelling resistance of MANET is connected with these centres of strain, probably connected with the formation, in ferrite, of Cr-enriched and contiguous Cr-depleted zones which may act as sinks for interstitials. Comparative observations on the internal strain behaviour of cold worked 316L stainless steel appear consistent with this possibility.

Water runoff vs modern climatic warming in mountainous cryolithic zone in North-East Russia

Science.gov (United States)

Glotov, V. E.; Glotova, L. P.

2018-01-01

The article presents the results of studying the effects of current climatic warming for both surface and subsurface water runoffs in North-East Russia, where the Main Watershed of the Earth separates it into the Arctic and Pacific continental slopes. The process of climatic warming is testified by continuous weather records during 80-100 years and longer periods. Over the Arctic slope and in the northern areas of the Pacific slope, climatic warming results in a decline in a total runoff of rivers whereas the ground-water recharge becomes greater in winter low-level conditions. In the southern Pacific slope and in the Sea of Okhotsk basin, the effect of climatic warming is an overall increase in total runoff including its subsurface constituents. We believe these peculiar characters of river runoff there to be related to the cryolithic zone environments. Over the Arctic slope and the northern Pacific slope, where cryolithic zone is continuous, the total runoff has its subsurface constituent as basically resulting from discharge of ground waters hosted in seasonally thawing rocks. Warmer climatic conditions favor growth of vegetation that needs more water for the processes of evapotranspiration and evaporation from rocky surfaces in summer seasons. In the Sea of Okhotsk basin, where the cryolithic zone is discontinuous, not only ground waters in seasonally thawing layers, but also continuous taliks and subpermafrost waters participate in processes of river recharges. As a result, a greater biological productivity of vegetation cover does not have any effect on ground-water supply and river recharge processes. If a steady climate warming is provided, a continuous cryolithic zone can presumably degrade into a discontinuous and then into an island-type permafrost layer. Under such a scenario, there will be a general increase in the total runoff and its subsurface constituent. From geoecological viewpoints, a greater runoff will have quite positive effects, whereas some

The interaction between freezing tolerance and phenology in temperate deciduous trees

Directory of Open Access Journals (Sweden)

Yann eVitasse

2014-10-01

Full Text Available Temperate climates are defined by a distinct temperature seasonality with large and often unpredictable weather during any of the four seasons. To thrive in such climates, trees have to withstand a cold winter and the stochastic occurrence of freeze events during any time of the year. The physiological mechanisms trees adopt to escape, avoid and tolerate freezing temperatures include a cold acclimation in autumn, a dormancy period during winter (leafless in deciduous trees, and the maintenance of a certain freezing tolerance during dehardening in early spring. The change from one phase to the next is mediated by complex interactions between temperature and photoperiod. This review aims at providing an overview of the interplay between phenology of leaves and species-specific freezing resistance. First, we address the long-term evolutionary responses that enabled temperate trees to tolerate certain low temperature extremes. We provide evidence that short term acclimation of freezing resistance plays a crucial role both in dormant and active buds, including re-acclimation to cold conditions following warm spells. This ability declines to almost zero during leaf emergence. Second, we show that the risk that native temperate trees encounter freeze injuries is low and is confined to spring and underline that this risk might be altered by climate warming depending on species-specific phenological responses to environmental cues.

Predicting Impacts of Climate Change on the Aboveground Carbon Sequestration Rate of a Temperate Forest in Northeastern China

Science.gov (United States)

Ma, Jun; Hu, Yuanman; Bu, Rencang; Chang, Yu; Deng, Huawei; Qin, Qin

2014-01-01

The aboveground carbon sequestration rate (ACSR) reflects the influence of climate change on forest dynamics. To reveal the long-term effects of climate change on forest succession and carbon sequestration, a forest landscape succession and disturbance model (LANDIS Pro7.0) was used to simulate the ACSR of a temperate forest at the community and species levels in northeastern China based on both current and predicted climatic data. On the community level, the ACSR of mixed Korean pine hardwood forests and mixed larch hardwood forests, fluctuated during the entire simulation, while a large decline of ACSR emerged in interim of simulation in spruce-fir forest and aspen-white birch forests, respectively. On the species level, the ACSR of all conifers declined greatly around 2070s except for Korean pine. The ACSR of dominant hardwoods in the Lesser Khingan Mountains area, such as Manchurian ash, Amur cork, black elm, and ribbed birch fluctuated with broad ranges, respectively. Pioneer species experienced a sharp decline around 2080s, and they would finally disappear in the simulation. The differences of the ACSR among various climates were mainly identified in mixed Korean pine hardwood forests, in all conifers, and in a few hardwoods in the last quarter of simulation. These results indicate that climate warming can influence the ACSR in the Lesser Khingan Mountains area, and the largest impact commonly emerged in the A2 scenario. The ACSR of coniferous species experienced higher impact by climate change than that of deciduous species. PMID:24763409

Predicting impacts of climate change on the aboveground carbon sequestration rate of a temperate forest in northeastern China.

Directory of Open Access Journals (Sweden)

Jun Ma

Full Text Available The aboveground carbon sequestration rate (ACSR reflects the influence of climate change on forest dynamics. To reveal the long-term effects of climate change on forest succession and carbon sequestration, a forest landscape succession and disturbance model (LANDIS Pro7.0 was used to simulate the ACSR of a temperate forest at the community and species levels in northeastern China based on both current and predicted climatic data. On the community level, the ACSR of mixed Korean pine hardwood forests and mixed larch hardwood forests, fluctuated during the entire simulation, while a large decline of ACSR emerged in interim of simulation in spruce-fir forest and aspen-white birch forests, respectively. On the species level, the ACSR of all conifers declined greatly around 2070s except for Korean pine. The ACSR of dominant hardwoods in the Lesser Khingan Mountains area, such as Manchurian ash, Amur cork, black elm, and ribbed birch fluctuated with broad ranges, respectively. Pioneer species experienced a sharp decline around 2080s, and they would finally disappear in the simulation. The differences of the ACSR among various climates were mainly identified in mixed Korean pine hardwood forests, in all conifers, and in a few hardwoods in the last quarter of simulation. These results indicate that climate warming can influence the ACSR in the Lesser Khingan Mountains area, and the largest impact commonly emerged in the A2 scenario. The ACSR of coniferous species experienced higher impact by climate change than that of deciduous species.

The Climate Change Vulnerability and Risk Management Matrix for the Coastal Zone of The Gambia

Directory of Open Access Journals (Sweden)

Joshua Amuzu

2018-02-01

Full Text Available Global Climate Change is one of the dire challenges facing the international community today. Coastal zones are vulnerable to its impacts. An effective approach with long-term prospects in addressing climate change impacts is it’s mainstreaming into development agenda of sectoral policies. A comprehensive risk and vulnerability assessment is a pre-requisite to ensure that the right adaptive response is taken for effective integration into developmental plans. The objective of this study is to evaluate and prioritize risks, vulnerability and adaptation issues of current and anticipated impacts of climate change on the coastal zone of The Gambia. The study will also give a methodological contribution for assessing risks, vulnerability and adaptation from the sub-national to local levels. The relevance of this study will be to create a link between the sub-national and local levels in order to facilitate the integration and mainstreaming of climate change into sectoral and local policies for more climate-resilient communities. This will aid in the promotion of strategic investment of constrained developmental resources to actualize successfully dynamic coping strategies, elude ‘maladaptation’ and less compelling responsive measures. A purposive expert sampling technique was used in selecting respondents for the study. The findings of the study reveal that by the end of the 21st century, the climatic variables likely to have the highest impact on the coastal zone of The Gambia are ‘increased flood severity’ and ‘increased temperature’. The coastal zone of The Gambia showed a high vulnerability to these climate change variables. The suggested adaptive response in addressing the impacts of increased flood intensity in the study area includes; improving regulations for restricting agriculture and livestock grazing activities to improve land cover; strengthening of early-warning systems, among others. The suggested adaptive response in

Correlation Between Intercritical Heat-Affected Zone and Type IV Creep Damage Zone in Grade 91 Steel

Science.gov (United States)

Wang, Yiyu; Kannan, Rangasayee; Li, Leijun

2018-04-01

A soft zone in Cr-Mo steel weldments has been reported to accompany the infamous Type IV cracking, the highly localized creep damage in the heat-affected zone of creep-resistant steels. However, the microstructural features and formation mechanism of this soft zone are not well understood. In this study, using microhardness profiling and microstructural verification, the initial soft zone in the as-welded condition was identified to be located in the intercritical heat-affected zone of P91 steel weldments. It has a mixed structure, consisting of Cr-rich re-austenitized prior austenite grains and fine Cr-depleted, tempered martensite grains retained from the base metal. The presence of these further-tempered retained grains, originating from the base metal, is directly responsible for the hardness reduction of the identified soft zone in the as-welded condition. The identified soft zone exhibits a high location consistency at three thermal stages. Local chemistry analysis and thermodynamic calculation show that the lower chromium concentrations inside these retained grains thermodynamically decrease their potentials for austenitic transformation during welding. Heterogeneous grain growth is observed in the soft zone during postweld heat treatment. The mismatch of strengths between the weak Cr-depleted grains and strong Cr-rich grains enhances the creep damage. Local deformation of the weaker Cr-depleted grains accelerates the formation of creep cavities.

Rainfall variability and drought characteristics in two agro-climatic zones: An assessment of climate change challenges in Africa.

Science.gov (United States)

Ayanlade, Ayansina; Radeny, Maren; Morton, John F; Muchaba, Tabitha

2018-07-15

This paper examines drought characteristics as an evidence of climate change in two agro-climatic zones of Nigeria and farmers' climate change perceptions of impacts and adaptation strategies. The results show high spatial and temporal rainfall variability for the stations. Consequently, there are several anomalies in rainfall in recent years but much more in the locations around the Guinea savanna. The inter-station and seasonality statistics reveal less variable and wetter early growing seasons and late growing seasons in the Rainforest zone, and more variable and drier growing seasons in other stations. The probability (p) of dry spells exceeding 3, 5 and 10 consecutive days is very high with 0.62≤p≥0.8 in all the stations, though, the p-values for 10day spells drop below 0.6 in Ibadan and Osogbo. The results further show that rainfall is much more reliable from the month of May until July with the coefficient of variance for rainy days 0.30), though CV-RD appears higher in the month of August for all the stations. It is apparent that farmers' perceptions of drought fundamentally mirror climatic patterns from historical weather data. The study concludes that the adaptation facilities and equipment, hybrids of crops and animals are to be provided to farmers, at a subsidized price by the government, for them to cope with the current condition of climate change. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Local Climate Zones Classification to Urban Planning in the Mega City of São Paulo - SP, Brazil

Science.gov (United States)

Gonçalves Santos, Rafael; Saraiva Lopes, António Manuel; Prata-Shimomura, Alessandra

2017-04-01

Local Climate Zones Classification to Urban Planning in the Mega city of São Paulo - SP, Brazil Tropical megacities have presented a strong trend in growing urban. Urban management in megacities has as one of the biggest challenges is the lack of integration of urban climate and urban planning to promote ecologically smart cities. Local Climatic Zones (LCZs) are considered as important and recognized tool for urban climate management. Classes are local in scale, climatic in nature, and zonal in representation. They can be understood as regions of uniform surface cover, structure, material and human activity that have to a unique climate response. As an initial tool to promote urban climate planning, LCZs represent a simple composition of different land coverages (buildings, vegetation, soils, rock, roads and water). LCZs are divided in 17 classes, they are based on surface cover (built fraction, soil moisture, albedo), surface structure (sky view factor, roughness height) and cultural activity (anthropogenic heat flux). The aim of this study is the application of the LCZs classification system in the megacity of São Paulo, Brazil. Located at a latitude of 23° 21' and longitude 46° 44' near to the Tropic of Capricorn, presenting humid subtropical climate (Cfa) with diversified topographies. The megacity of São Paulo currently concentrates 11.890.000 inhabitants is characterized by large urban conglomerates with impermeable surfaces and high verticalization, having as result high urban heat island intensity. The result indicates predominance in urban zones of Compact low-rise, Compact Mid-rise, Compact High-rise and Open Low-rise. Non-urban regions are mainly covered by dense vegetation and water. The LCZs classification system promotes significant advantages for climate sensitive urban planning in the megacity of São Paulo. They offers new perspectives to the management of temperature and urban ventilation and allows the formulation of urban planning

Can behaviour buffer the impacts of climate change on an arid-zone ...

African Journals Online (AJOL)

Can behaviour buffer the impacts of climate change on an arid-zone bird? ... These could include reduced opportunity for foraging, breeding or territorial defence, each ... We investigated patterns of microclimate use and foraging behaviour by ...

The impact of climate change on future land-use in a coastal zone planning context

DEFF Research Database (Denmark)

Hansen, Henning Sten

2008-01-01

Climate change has received much attention during the last decennium and especially various mitigation and adaptation strategies. Particularly the coastal zone will feel the consequences of climate change and the associated effects like sea level rise, increased storminess and flooding. Thus...

Invasion of the tropical earthworm Pontoscolex corethrurus (Rhinodrilidae, Oligochaeta in temperate grasslands

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Diana Ortiz-Gamino

2016-10-01

Full Text Available The tropical earthworm Pontoscolex corethrurus (Rhinodrilidae, Oligochaeta presents a broad distribution (e.g., 56 countries from four continents. It is generally assumed that temperature appears to limit the success of tropical exotic species in temperate climates. However, the distribution range of this species could advance towards higher elevations (with lower temperatures where no tropical species currently occur. The aim of this study was to evaluate the soil and climatic variables that could be closely associated with the distribution of P. corethrurus in four sites along an altitudinal gradient in central Veracruz, Mexico. We predicted that the distribution of P. corethrurus would be more related to climate variables than edaphic parameters. Five sampling points (in the grassland were established at each of four sites along an altitudinal gradient: Laguna Verde (LV, La Concepción (LC, Naolinco (NA and Acatlán (AC at 11–55, 992–1,025, 1,550–1,619 y 1,772–1,800 masl, respectively. The climate ranged from tropical to temperate along the altitudinal gradient. Ten earthworm species (5 Neotropical, 4 Palearctic and 1 Nearctic were found along the gradient, belonging to three families (Rhinodrilidae, Megascolecide and Lumbricidae. Soil properties showed a significant association (positive for Ngrass, pH, permanent wilting point, organic matter and P; and negative for Total N, K and water-holding capacity with the abundance of the earthworm community. Also there seems to be a relationship between climate and earthworm distribution along the altitudinal gradient. P. corethrurus was recorded at tropical (LV and LC and temperate sites (NA along the altitudinal gradient. Our results reveal that soil fertility determines the abundance of earthworms and site (climate can act as a barrier to their migration. Further research is needed to determine the genetic structure and lineages of P. corethrurus along altitudinal gradients.

Thermal tolerance ranges and climate variability : A comparison between bivalves from differing climates

NARCIS (Netherlands)

Compton, Tanya J.; Rijkenberg, Micha J. A.; Drent, Jan; Piersma, Theunis

2007-01-01

The climate variability hypothesis proposes that in variable temperate climates poikilothermic animals have wide thermal tolerance windows, whereas in constant tropical climates they have small thermal tolerance windows. In this study we quantified and compared the upper and lower lethal thermal

Quantifying the relevance of adaptive thermal comfort models in moderate thermal climate zones

Energy Technology Data Exchange (ETDEWEB)

Hoof, Joost van; Hensen, Jan L.M. [Faculty of Architecture, Building and Planning, Technische Universiteit Eindhoven, Vertigo 6.18, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2007-01-15

Standards governing thermal comfort evaluation are on a constant cycle of revision and public review. One of the main topics being discussed in the latest round was the introduction of an adaptive thermal comfort model, which now forms an optional part of ASHRAE Standard 55. Also on a national level, adaptive thermal comfort guidelines come into being, such as in the Netherlands. This paper discusses two implementations of the adaptive comfort model in terms of usability and energy use for moderate maritime climate zones by means of literature study, a case study comprising temperature measurements, and building performance simulation. It is concluded that for moderate climate zones the adaptive model is only applicable during summer months, and can reduce energy for naturally conditioned buildings. However, the adaptive thermal comfort model has very limited application potential for such climates. Additionally we suggest a temperature parameter with a gradual course to replace the mean monthly outdoor air temperature to avoid step changes in optimum comfort temperatures. (author)

Plant nutrient mobilization in temperate heathland responds to elevated CO2, temperature and drought

DEFF Research Database (Denmark)

Andresen, Louise C.; Michelsen, Anders; Jonasson, Sven

2010-01-01

Temperate terrestrial ecosystems are currently exposed to increased atmospheric CO2 and progressive climatic changes with increased temperature and periodical drought. We here present results from a field experiment, where the effects of these three main climate change related factors...... decreased in response to drought. These complex changes in availability and release of nutrients from soil organic matter turnover and mineralization in response to elevated CO2 and climate change may influence the future plant carbon sequestration and species composition at temperate heathlands....... in Deschampsia soil, and microbial immobilization of N and P decreased in warmed Calluna soil. Warming tended to increase microbial N and P in Calluna but not in Deschampsia soil in fall, and more microbial C was accumulated under drought in Calluna soil. The effects of warming were often counteracted or erased...

The Climate Range Expansion of Aedes albopictus (Diptera: Culicidae) in Asia Inferred From the Distribution of Albopictus Subgroup Species of Aedes (Stegomyia).

Science.gov (United States)

Mogi, M; Armbruster, P A; Tuno, N; Aranda, C; Yong, H S

2017-11-07

We compared climatic distribution ranges between Aedes albopictus (Skuse) (Diptera: Culicidae) and the five wild (nondomesticated) species of Albopictus Subgroup of Scutellaris Group of Aedes (Stegomyia) in southern Asia. Distribution sites of the wild species concentrate in seasonal forest and savannah climate zones in India, Indochina, and southern China. The distribution of Ae. albopictus is broader than the wild species under 1) tropical rain-forest climate, 2) steppe and temperate savannah climate, and 3) continental climate with large seasonal temperature variation (hot summer and cold winter) at temperate lowlands (northernmost sites 40°N in Ae. albopictus vs 32°N in the wild species). However, the distribution of Ae. albopictus is more limited at tropical and subtropical highlands where the climate is cool but less continental (small seasonal variation, mild summer, and winter). We discuss a possibility that the broader climate ranges of Ae. albopictus are ecological or eco-evolutionary consequences of adaptation to human habitats. We also propose a general scenario for the origin, dispersal, and adaptation of Ae. albopictus in Asia as a hypothesis for future research. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Plant molecular phylogeography in China and adjacent regions: Tracing the genetic imprints of Quaternary climate and environmental change in the world's most diverse temperate flora.

Science.gov (United States)

Qiu, Ying-Xiong; Fu, Cheng-Xing; Comes, Hans Peter

2011-04-01

The Sino-Japanese Floristic Region (SJFR) of East Asia harbors the most diverse of the world's temperate flora, and was the most important glacial refuge for its Tertiary representatives ('relics') throughout Quaternary ice-age cycles. A steadily increasing number of phylogeographic studies in the SJFR of mainland China and adjacent areas, including the Qinghai-Tibetan-Plateau (QTP) and Sino-Himalayan region, have documented the population histories of temperate plant species in these regions. Here we review this current literature that challenges the oft-stated view of the SJFR as a glacial sanctuary for temperate plants, instead revealing profound effects of Quaternary changes in climate, topography, and/or sea level on the current genetic structure of such organisms. There are three recurrent phylogeographic scenarios identified by different case studies that broadly agree with longstanding biogeographic or palaeo-ecological hypotheses: (i) postglacial re-colonization of the QTP from (south-)eastern glacial refugia; (ii) population isolation and endemic species formation in Southwest China due to tectonic shifts and river course dynamics; and (iii) long-term isolation and species survival in multiple localized refugia of (warm-)temperate deciduous forest habitats in subtropical (Central/East/South) China. However, in four additional instances, phylogeographic findings seem to conflict with a priori predictions raised by palaeo-data, suggesting instead: (iv) glacial in situ survival of some hardy alpine herbs and forest trees on the QTP platform itself; (v) long-term refugial isolation of (warm-)temperate evergreen taxa in subtropical China; (vi) 'cryptic' glacial survival of (cool-)temperate deciduous forest trees in North China; and (vii) unexpectedly deep (Late Tertiary/early-to-mid Pleistocene) allopatric-vicariant differentiation of disjunct lineages in the East China-Japan-Korea region due to past sea transgressions. We discuss these and other consequences

Prediction of spatial patterns of collapsed pipes in loess-derived soils in a temperate humid climate using logistic regression

Science.gov (United States)

Verachtert, E.; Den Eeckhaut, M. Van; Poesen, J.; Govers, G.; Deckers, J.

2011-07-01

Soil piping (tunnel erosion) has been recognised as an important erosion process in collapsible loess-derived soils of temperate humid climates, which can cause collapse of the topsoil and formation of discontinuous gullies. Information about the spatial patterns of collapsed pipes and regional models describing these patterns is still limited. Therefore, this study aims at better understanding the factors controlling the spatial distribution and predicting pipe collapse. A dataset with parcels suffering from collapsed pipes (n = 560) and parcels without collapsed pipes was obtained through a regional survey in a 236 km² study area in the Flemish Ardennes (Belgium). Logistic regression was applied to find the best model describing the relationship between the presence/absence of a collapsed pipe and a set of independent explanatory variables (i.e. slope gradient, drainage area, distance-to-thalweg, curvature, aspect, soil type and lithology). Special attention was paid to the selection procedure of the grid cells without collapsed pipes. Apart from the first piping susceptibility map created by logistic regression modelling, a second map was made based on topographical thresholds of slope gradient and upslope drainage area. The logistic regression model allowed identification of the most important factors controlling pipe collapse. Pipes are much more likely to occur when a topographical threshold depending on both slope gradient and upslope area is exceeded in zones with a sufficient water supply (due to topographical convergence and/or the presence of a clay-rich lithology). On the other hand, the use of slope-area thresholds only results in reasonable predictions of piping susceptibility, with minimum information.

Climate change effects on nitrogen loading from cultivated catchments in Europe: implications for nitrogen retention, ecological state of lakes and adaptation

DEFF Research Database (Denmark)

Jeppesen, Erik; Kronvang, Brian; Olesen, Jørgen E

2011-01-01

and changes in cropping patterns. Scenario (IPCC, A2) analyses using a number of models of various complexity for Danish streams and lakes suggest an increase in runoff and N transport on an annual basis (higher during winter and typically lower during summer) in streams, a slight increase in N concentrations...... shifts from clear to turbid in a warmer North European temperate climate. However, it must be emphasised that the prediction of N transport and thus effects is uncertain as the prediction of regional precipitation and changes in land-use is uncertain. By contrast, N loading is expected to decline in warm...... agricultural practices for reducing the loss of nutrients to surface waters, to improve sewage treatment and to reduce the storm-water nutrient runoff. In north temperate zones adaptations may also include re-establishment of artificial and natural wetlands, introduction of riparian buffer zones and re...

How soil water storage moderates climate changes effects on transpiration, across the different climates of the Critical Zone Observatories

Science.gov (United States)

Heckman, C.; Tague, C.

2017-12-01

While the demand side of transpiration is predicted to increase under a warmer climate, actual evapotranspiration (AET) will be moderated by the supply of water available to vegetation. A key question to ask is how will plant accessible water storage capacity (PAWSC) affect the partitioning of precipitation between AET and runoff. Our results indicate that whether AET increases or decreases, and how much, is significantly based upon interactions between PAWSC and characteristics of precipitation such as the amount, frequency, and skew as well the partitioning between rain and snow. In snow dominated climates, if PAWSC cannot make up for the loss of storage as snowpack then AET could decrease, and in rain dominated climates, PAWSC could significantly limit the increase in AET. These results highlight the importance of critical zone research: constraining PAWSC is critical in predicting not only the magnitude but also the direction of the change in AET with climate warming. Due to the highly heterogeneous nature of PAWSC and the difficulty of measuring it across large scales, we use a well-tested hydrologic model to estimate the impacts from a range of PAWSC on the partitioning of precipitation between runoff and AET. We completed this analysis for the range of precipitation and vegetation characteristics found across 9 of the Critical Zone Observatories.

Responses of Winter Wheat Yields to Warming-Mediated Vernalization Variations Across Temperate Europe

Directory of Open Access Journals (Sweden)

Xiuchen Wu

2017-10-01

Full Text Available Rapid climate warming, with much higher warming rates in winter and spring, could affect the vernalization fulfillment, a critical process for induction of crop reproductive growth and consequent grain filling in temperate winter crops. However, regional observational evidence of the effects of historical warming-mediated vernalization variations on temperate winter crop yields is lacking. Here, we statistically quantified the interannual sensitivity of winter wheat yields to vernalization degree days (VDD during 1975–2009 and its spatial relationship with multi-year mean VDD over temperate Europe (TE, using EUROSTAT crop yield statistics, observed and simulated crop phenology data and gridded daily climate data. Our results revealed a pervasively positive interannual sensitivity of winter wheat yields to variations in VDD (γVDD over TE, with a mean γVDD of 2.8 ± 1.5 kg ha−1 VDD−1. We revealed a significant (p < 0.05 negative exponential relationship between γVDD and multi-year mean VDD for winter wheat across TE, with higher γVDD in winter wheat planting areas with lower multi-year mean VDD. Our findings shed light on potential vulnerability of winter wheat yields to warming-mediated vernalization variations over TE, particularly considering a likely future warmer climate.

Effects of Atlantic warm pool variability over climate of South America tropical transition zone

Science.gov (United States)

Ricaurte Villota, Constanza; Romero-Rodríguez, Deisy; Andrés Ordoñez-Zuñiga, Silvio; Murcia-Riaño, Magnolia; Coca-Domínguez, Oswaldo

2016-04-01

Colombia is located in the northwestern corner of South America in a climatically complex region due to the influence processes modulators of climate both the Pacific and Atlantic region, becoming in a transition zone between phenomena of northern and southern hemisphere. Variations in the climatic conditions of this region, especially rainfall, have been attributed to the influence of the El Nino Southern Oscillation (ENSO), but little is known about the interaction within Atlantic Ocean and specifically Caribbean Sea with the environmental conditions of this region. In this work We studied the influence of the Atlantic Warm Pool (AWP) on the Colombian Caribbean (CC) climate using data of Sea Surface Temperature (SST) between 1900 - 2014 from ERSST V4, compared with in situ data SIMAC (National System for Coral Reef Monitoring in Colombia - INVEMAR), rainfall between 1953-2013 of meteorological stations located at main airports in the Colombian Caribbean zone, administered by IDEAM, and winds data between 2003 - 2014 from WindSat sensor. The parameters analyzed showed spatial differences throughout the study area. SST anomalies, representing the variability of the AWP, showed to be associated with Multidecadal Atlantic Oscillation (AMO) and with the index of sea surface temperature of the North-tropical Atlantic (NTA), the variations was on 3 to 5 years on the ENSO scale and of approximately 11 years possibly related to solar cycles. Rainfall anomalies in the central and northern CC respond to changes in SST, while in the south zone these are not fully engage and show a high relationship with the ENSO. Finally, the winds also respond to changes in SST and showed a signal approximately 90 days possibly related to the Madden-Julian Oscillation, whose intensity depends on the CC region being analyzed. The results confirm that region is a transition zone in which operate several forcing, the variability of climate conditions is difficult to attribute only one, as ENSO

Tropical and Highland Temperate Forest Plantations in Mexico: Pathways for Climate Change Mitigation and Ecosystem Services Delivery

Directory of Open Access Journals (Sweden)

Vidal Guerra-De la Cruz

2017-12-01

Full Text Available Forest plantations are a possible way of increasing forest productivity in temperate and tropical forests, and therefore also increasing above- and belowground carbon pools. In the context of climate change, monospecific plantations might become an alternative to mitigate global warming; however, their contribution to the structural complexity, complementarity, and biodiversity of forests has not been addressed. Mixed forest plantations can ensure that objectives of climate change mitigation are met through carbon sequestration, while also delivering anticipated ecosystem services (e.g., nutrient cycling, erosion control, and wildlife habitat. However, mixed forest plantations pose considerable operational challenges and research opportunities. For example, it is essential to know how many species or functional traits are necessary to deliver a set of benefits, or what mixture of species and densities are key to maintaining productive plantations and delivering multiple ecosystem services. At the same time, the establishment of forest plantations in Mexico should not be motivated solely by timber production. Forest plantations should also increase carbon sequestration, maintain biodiversity, and provide other ecosystem services. This article analyzes some matters that affect the development of planted forests in the Mexican national context, and presents alternatives for forest resources management through the recommendation of mixed forest plantations as a means of contributing to climate change mitigation and the delivery of ecosystem services.

Estimating Climate Trends: Application to United States Plant Hardiness Zones

Directory of Open Access Journals (Sweden)

Nir Y. Krakauer

2012-01-01

Full Text Available The United States Department of Agriculture classifies plant hardiness zones based on mean annual minimum temperatures over some past period (currently 1976–2005. Since temperatures are changing, these values may benefit from updating. I outline a multistep methodology involving imputation of missing station values, geostatistical interpolation, and time series smoothing to update a climate variable’s expected value compared to a climatology period and apply it to estimating annual minimum temperature change over the coterminous United States. I show using hindcast experiments that trend estimation gives more accurate predictions of minimum temperatures 1-2 years in advance compared to the previous 30 years’ mean alone. I find that annual minimum temperature increased roughly 2.5 times faster than mean temperature (~2.0 K versus ~0.8 K since 1970, and is already an average of 1.2  0.5 K (regionally up to ~2 K above the 1976–2005 mean, so that much of the country belongs to warmer hardiness zones compared to the current map. The methods developed may also be applied to estimate changes in other climate variables and geographic regions.

Effects of Climatic Region on Peritonitis Risk, Microbiology, Treatment, and Outcomes: a Multicenter Registry Study

Science.gov (United States)

Cho, Yeoungjee; Badve, Sunil V.; Hawley, Carmel M.; McDonald, Stephen P.; Brown, Fiona G.; Boudville, Neil; Wiggins, Kathryn J.; Bannister, Kym M.; Clayton, Philip; Johnson, David W.

2013-01-01

♦ Background: The impact of climatic variations on peritoneal dialysis (PD)-related peritonitis has not been studied in detail. The aim of the current study was to determine whether various climatic zones influenced the probability of occurrence or the clinical outcomes of peritonitis. ♦ Methods: Using ANZDATA registry data, the study in cluded all Australian patients receiving PD between 1 October 2003 and 31 December 2008. Climatic regions were defined according to the Köppen classification. ♦ Results: The overall peritonitis rate was 0.59 episodes per patient-year. Most of the patients lived in Temperate regions (65%), with others residing in Subtropical (26%), Tropical (6%), and Other climatic regions (Desert, 0.6%; Grassland, 2.3%). Compared with patients in Temperate regions, those in Tropical regions demonstrated significantly higher overall peritonitis rates and a shorter time to a first peritonitis episode [adjusted hazard ratio: 1.15; 95% confidence interval (CI): 1.01 to 1.31]. Culture-negative peritonitis was significantly less likely in Tropical regions [adjusted odds ratio (OR): 0.42; 95% CI: 0.25 to 0.73]; its occurrence in Subtropical and Other regions was comparable to that in Temperate regions. Fungal peritonitis was independently associated with Tropical regions (OR: 2.18; 95% CI: 1.22 to 3.90) and Other regions (OR: 3.46; 95% CI: 1.73 to 6.91), where rates of antifungal prophylaxis were also lower. Outcomes after first peritonitis episodes were comparable in all groups. ♦ Conclusions: Tropical regions were associated with a higher overall peritonitis rate (including fungal peritonitis) and a shorter time to a first peritonitis episode. Augmented peritonitis prophylactic measures such as antifungal therapy and exit-site care should be considered in PD patients residing in Tropical climates. PMID:22942270

Can temperate insects take the heat? A case study of the physiological and behavioural responses in a common ant, Iridomyrmex purpureus (Formicidae), with potential climate change.

Science.gov (United States)

Andrew, Nigel R; Hart, Robert A; Jung, Myung-Pyo; Hemmings, Zac; Terblanche, John S

2013-09-01

Insects in temperate regions are predicted to be at low risk of climate change relative to tropical species. However, these assumptions have generally been poorly examined in all regions, and such forecasting fails to account for microclimatic variation and behavioural optimisation. Here, we test how a population of the dominant ant species, Iridomyrmex purpureus, from temperate Australia responds to thermal stress. We show that ants regularly forage for short periods (minutes) at soil temperatures well above their upper thermal limits (upper lethal temperature = 45.8 ± 1.3°C; CT(max) = 46.1°C) determined over slightly longer periods (hours) and do not show any signs of a classic thermal performance curve in voluntary locomotion across soil surface temperatures of 18.6-57°C (equating to a body temperature of 24.5-43.1°C). Although ants were present all year round, and dynamically altered several aspects of their thermal biology to cope with low temperatures and seasonal variation, temperature-dependence of running speed remained invariant and ants were unable to elevate high temperature tolerance using plastic responses. Measurements of microclimate temperature were higher than ant body temperatures during the hottest part of the day, but exhibited a stronger relationship with each other than air temperatures from the closest weather station. Generally close associations of ant activity and performance with microclimatic conditions, possibly to maximise foraging times, suggest I. purpureus displays highly opportunistic thermal responses and readily adjusts behaviour to cope with high trail temperatures. Increasing frequency or duration of high temperatures is therefore likely to result in an immediate reduction in foraging efficiency. In summary, these results suggest that (1) soil-dwelling temperate insect populations may be at higher risks of thermal stress with increased frequency or duration of high temperatures resulting from climate change than

Assessing the Effects of Climate on Global Fluvial Discharge Variability

Science.gov (United States)

Hansford, M. R.; Plink-Bjorklund, P.

2017-12-01

Plink-Bjorklund (2015) established the link between precipitation seasonality and river discharge variability in the monsoon domain and subtropical rivers (see also Leier et al, 2005; Fielding et al., 2009), resulting in distinct morphodynamic processes and a sedimentary record distinct from perennial precipitation zone in tropical rainforest zone and mid latitudes. This study further develops our understanding of discharge variability using a modern global river database created with data from the Global Runoff Data Centre (GRDC). The database consists of daily discharge for 595 river stations and examines them using a series of discharge variability indexes (DVI) on different temporal scales to examine how discharge variability occurs in river systems around the globe. These indexes examine discharge of individual days and monthly averages that allows for comparison of river systems against each other, regardless of size of the river. Comparing river discharge patterns in seven climate zones (arid, cold, humid subtropics, monsoonal, polar, rainforest, and temperate) based off the Koppen-Geiger climate classifications reveals a first order climatic control on discharge patterns and correspondingly sediment transport. Four groupings of discharge patterns emerge when coming climate zones and DVI: persistent, moderate, seasonal, and erratic. This dataset has incredible predictive power about the nature of discharge in fluvial systems around the world. These seasonal effects on surface water supply affects river morphodynamics and sedimentation on a wide timeframe, ranging from large single events to an inter-annual or even decadal timeframe. The resulting sedimentary deposits lead to differences in fluvial architecture on a range of depositional scales from sedimentary structures and bedforms to channel complex systems. These differences are important to accurately model for several reasons, ranging from stratigraphic and paleoenviromental reconstructions to more

Forests in a water limited world under climate change

International Nuclear Information System (INIS)

Mátyás, Csaba; Sun, Ge

2014-01-01

The debate on ecological and climatic benefits of planted forests at the sensitive dry edge of the closed forest belt (i.e. at the ‘xeric limits’) is still unresolved. Forests sequester atmospheric carbon dioxide, accumulate biomass, control water erosion and dust storms, reduce river sedimentation, and mitigate small floods. However, planting trees in areas previously dominated by grassland or cropland can dramatically alter the energy and water balances at multiple scales. The forest/grassland transition zone is especially vulnerable to projected drastic temperature and precipitation shifts and growing extremes due to its high ecohydrological sensitivity. We investigated some of the relevant aspects of the ecological and climatic role of forests and potential impacts of climate change at the dryland margins of the temperate-continental zone using case studies from China, the United States and SE Europe (Hungary). We found that, contrary to popular expectations, the effects of forest cover on regional climate might be limited and the influence of forestation on water resources might be negative. Planted forests generally reduce stream flow and lower groundwater table level because of higher water use than previous land cover types. Increased evaporation potential due to global warming and/or extreme drought events is likely to reduce areas that are appropriate for tree growth and forest establishment. Ecologically conscious forest management and forestation planning should be adjusted to the local, projected hydrologic and climatic conditions, and should also consider non-forest alternative land uses. (paper)

Relative Linkages of Stream Dissolved Oxygen with the Climatic, Hydrological, and Biogeochemical Drivers across the East Coast of U.S.A.

Science.gov (United States)

Abdul-Aziz, O. I.; Ahmed, S.

2017-12-01

Dissolved oxygen (DO) is a key indicator of stream water quality and ecosystem health. However, the temporal dynamics of stream DO is controlled by a multitude of interacting environmental drivers. The relative linkages of stream DO with the relevant environmental drivers were determined in this study across the U.S. East Coast by employing a systematic data analytics approach. The study analyzed temporal data for 51 water quality monitoring stations from USGS NWIS and EPA STORET databases. Principal component analysis and factor analysis, along with Pearson's correlation analysis, were applied to identify the interrelationships and unravel latent patterns among DO and the environmental drivers. Power law based partial least squares regression models with a bootstarp Monte-Carlo procedure (1000 iterations) were developed to reliably estimate the environmental linkages of DO by resolving multicollinearity. Based on the similarity of dominant drivers, the streams were categorized into three distinct environmental regimes. Stream DO in the northern part of temperate zone (e.g., northeast coast) had the strongest linkage with water temperature; suggesting an environmental regime with dominant climatic control. However, stream DO in the tropical zones (e.g., southeast Florida) was mostly driven by pH; indicating an environmental regime likely controlled by redox chemistry. Further, a transitional regime was found between the temperate and tropical zones, where stream DO was controlled by both water temperature and pH. The results suggested a strong effect of the climatic gradient (temperate to tropical) on stream DO along the East Coast. The identified environmental regimes and the regime-specific relative linkages provided new information on the dominant controls of coastal stream water quality dynamics. The findings would guide the planning and management of coastal stream water quality and ecosystem health across the U.S. East Coast and around the world.

Implications of climate change (global warming) for the healthcare system.

Science.gov (United States)

Raffa, R B; Eltoukhy, N S; Raffa, K F

2012-10-01

Temperature-sensitive pathogenic species and their vectors and hosts are emerging in previously colder regions as a consequence of several factors, including global warming. As a result, an increasing number of people will be exposed to pathogens against which they have not previously needed defences. We illustrate this with a specific example of recent emergence of Cryptococcus gattii infections in more temperate climates. The outbreaks in more temperate climates of the highly virulent--but usually tropically restricted--C. gattii is illustrative of an anticipated growing challenge for the healthcare system. There is a need for preparedness by healthcare professionals in anticipation and for management of such outbreaks, including other infections whose recent increased prevalence in temperate climates can be at least partly associated with global warming. (Re)emergence of temperature-sensitive pathogenic species in more temperate climates will present new challenges for healthcare systems. Preparation for outbreaks should precede their occurrence. © 2012 Blackwell Publishing Ltd.

Analyzing the Implications of Climate Data on Plant Hardiness Zones for Green Infrastructure Planning: Case Study of Knoxville, Tennessee and Surrounding Region

Energy Technology Data Exchange (ETDEWEB)

Sylvester, Linda M [ORNL; Omitaomu, Olufemi A [ORNL; Parish, Esther S [ORNL

2016-07-01

Downscaled climate data for Knoxville, Tennessee and the surrounding region were used to investigate future changing Plant Hardiness Zones due to climate change. The methodology used is the same as the US Department of Agriculture (USDA), well-known for their creation of the standard Plant Hardiness Zone map used by gardeners and planners. USDA data were calculated from observed daily data for 1976–2005. The modeled climate data for the past is daily data from 1980-2005 and the future data is projected for 2025–2050. The average of all the modeled annual extreme minimums for each time period of interest was calculated. Each 1 km raster cell was placed into zone categories based on temperature, using the same criteria and categories of the USDA. The individual models vary between suggesting little change to the Plant Hardiness Zones to suggesting Knoxville moves into the next two Hardiness Zones. But overall, the models suggest moving into the next warmer Zone. USDA currently has the Knoxville area categorized as Zone 7a. None of the Zones calculated from the climate data models placed Knoxville in Zone 7a for the similar time period. The models placed Knoxville in a cooler Hardiness Zone and projected the area to increase to Zone 7. The modeled temperature data appears to be slightly cooler than the actual temperature data and this may explain the zone discrepancy. However, overall Knoxville is projected to increase to the next warmer Zone. As the modeled data has Knoxville, overall, moving from Zone 6 to Zone 7, it can be inferred that Knoxville, Tennessee may increase from their current Zone 7 to Zone 8.

Economic feasibility of biochar application to soils in temperate climate regions

Science.gov (United States)

Soja, Gerhard; Bücker, Jannis; Gunczy, Stefan; Kitzler, Barbara; Klinglmüller, Michaela; Kloss, Stefanie; Watzinger, Andrea; Wimmer, Bernhard; Zechmeister-Boltenstern, Sophie; Zehetner, Franz

2014-05-01

The findings that fertility improvements in tropical soils have been successfully mediated by biochar applications have caused wide-spread interest to use biochar as a soil amendment also for soils in temperate climate regions. But these soils in intensively cultivated regions are not always as acidic or sandy as the tropical Ferralsols where biochar is most effective. Therefore it is not self-evident that different soil characteristics allow biochar to display the same benefits if site-specific demands for the optimal organic soil amendment are not considered. This study pursued the objective to study the extent of benefits that biochar could provide for crops on two typical Austrian agricultural soils in a two-year field experiment. An economic evaluation assessed the local biochar production costs and compared them with the value of the observed biochar benefits. From a business economic viewpoint, currently high costs of biochar are not balanced by only moderate increases in crop yields and thus agricultural revenues. Improved water retention due to biochar, however, might justify biochar as an adaptation measure to global warming, especially when considering beside business economic aspects also overall economic aspects. When not assuming total crop failures but only increased soil fertility, even an inclusion of avoided social (=societal) costs by sequestering carbon and thereby helping to mitigate climate change do not economically justify the application of biochar. Price of biochar would need to decrease by at least 40 % to achieve a break-even from the overall economic viewpoint (if optimistic assumptions about the social value of sequestered carbon are applied; at pessimistic assumptions price for biochar must decrease even more in order to break even). When applying an alternative type of soil treatment of using modified biochar but avoiding additional N-fertilization, a similar picture arises: Social benefits due to avoided N-fertilization and

ZoneLib

DEFF Research Database (Denmark)

Jessen, Jan Jacob; Schiøler, Henrik

2006-01-01

We present a dynamic model for climate in a livestock building divided into a number of zones, and a corresponding modular Simulink library (ZoneLib). While most literature in this area consider air flow as a control parameter we show how to model climate dynamics using actual control signals...... development of ZoneLib....

The Influence of Weather Anomalies on Mercury Cycling in the Marine Coastal Zone of the Southern Baltic-Future Perspective.

Science.gov (United States)

Bełdowska, Magdalena

2015-01-01

Despite the decreased emission loads of mercury, historical deposits of this metal in various compartments of the environment may become an additional diffuse source in the future. Global climate change manifests itself in the temperate zone in several ways: warmer winters, shorter icing periods, increased precipitation and heightened frequency of extreme events such as strong gales and floods, all of which cause disturbances in the rate and direction of mercury biogeochemical cycling. The present study was conducted at two sites, Oslonino and Gdynia Orlowo (both in the coastal zone of the Gulf of Gdansk), from which samples were collected once a month between January 2012 and December 2012. In the Southern Baltic region, climate changes can certainly enhance coast to basin fluxes of mercury and the transfer of bioavailable forms of this metal to the food web. They may also, in the future, contribute to uncontrollable increases of mercury in the seawater.

Hardness prediction of HAZ in temper bead welding by non-consistent layer technique

International Nuclear Information System (INIS)

Yu, Lina; Saida, Kazuyoshi; Mochizuki, Masahito; Kameyama, Masashi; Chigusa, Naoki; Nishimoto, Kazutoshi

2014-01-01

Based on the experimentally obtained hardness database, the neural network-based hardness prediction system of heat affect zone (HAZ) in temper bead welding by Consistent Layer (CSL) technique has been constructed by the authors. However in practical operation, CSL technique is sometimes difficult to perform because of difficulty of the precise heat input controlling, and in such case non-CSL techniques are mainly used in the actual repair process. Therefore in the present study, the neural network-based hardness prediction system of HAZ in temper bead welding by non-CSL techniques has been constructed through thermal cycle simplification, from the view of engineering. The hardness distribution in HAZ with non-CSL techniques was calculated based on the thermal cycles numerically obtained by finite element method. The experimental result has shown that the predicted hardness is in good accordance with the measured ones. It follows that the currently proposed method is effective for estimating the tempering effect during temper bead welding by non-CSL techniques. (author)

Modification of Low-Alloy Steel Surface by High-Temperature Gas Nitriding Plus Tempering

Science.gov (United States)

Jiao, Dongling; Li, Minsong; Ding, Hongzhen; Qiu, Wanqi; Luo, Chengping

2018-02-01

The low-alloy steel was nitrided in a pure NH3 gas atmosphere at 640 660 °C for 2 h, i.e., high-temperature gas nitriding (HTGN), followed by tempering at 225 °C, which can produce a high property surface coating without brittle compound (white) layer. The steel was also plasma nitriding for comparison. The composition, microstructure and microhardness of the nitrided and tempered specimens were examined, and their tribological behavior investigated. The results showed that the as-gas-nitrided layer consisted of a white layer composed of FeN0.095 phase (nitrided austenite) and a diffusional zone underneath the white layer. After tempering, the white layer was decomposed to a nano-sized (α-Fe + γ'-Fe4N + retained austenite) bainitic microstructure with a high hardness of 1150HV/25 g. Wear test results showed that the wear resistance and wear coefficient yielded by the complex HTGN plus tempering were considerably higher and lower, respectively, than those produced by the conventional plasma nitriding.

Data on experiments result of three identical huts with shape-stabilized phase change materials in Japanese temperate climate

Directory of Open Access Journals (Sweden)

Hyun Bae Kim

2018-04-01

Full Text Available The data in this article are the experimental results of three identical huts (Hut A, B and C, which were examined by using varying shape-stabilized PCMs (SSPCMs sheet levels under natural and heating conditions in winter of Chiba prefecture where Japanese temperate climate. The SSPCMs sheet established the melting and solidification-temperature ranged at 19–26 °C were used. In Hut A, no SSPCM sheets were applied; in Hut B, four layers of SSPCM sheets were applied to the floor; in Hut C, one layer of SSPCM was applied to the floor, walls, and ceilings. The data provide information on the application of SSPCM sheets to improve indoor stabilization and the heating load reduction effects.

[Climate- and vector-borne diseases

DEFF Research Database (Denmark)

Bygbjerg, I.C.; Schioler, K.L.; Konradsen, F.

2009-01-01

The predicted changes in climate have raised concerns that vector-borne diseases may emerge or expand in tempered regions. Malaria, leishmaniasis and tick-borne illnesses are discussed in terms of climate change and their endemic potential, especially in Denmark. While climate may play an important...

Effect of reservoir zones and hedging factor dynamism on reservoir adaptive capacity for climate change impacts

Science.gov (United States)

Adeloye, Adebayo J.; Soundharajan, Bankaru-Swamy

2018-06-01

When based on the zones of available water in storage, hedging has traditionally used a single hedged zone and a constant rationing ratio for constraining supply during droughts. Given the usual seasonality of reservoir inflows, it is also possible that hedging could feature multiple hedged zones and temporally varying rationing ratios but very few studies addressing this have been reported especially in relation to adaptation to projected climate change. This study developed and tested Genetic Algorithms (GA) optimised zone-based operating policies of various configurations using data for the Pong reservoir, Himachal Pradesh, India. The results show that hedging does lessen vulnerability, which dropped from ≥ 60 % without hedging to below 25 % with the single stage hedging. More complex hedging policies, e.g. two stage and/or temporally varying rationing ratios only produced marginal improvements in performance. All this shows that water hedging policies do not have to be overly complex to effectively offset reservoir vulnerability caused by water shortage resulting from e.g. projected climate change.

Determinação por cromatografia gasosa de açúcares em frutíferas de clima temperado Gas chromatography determination of sugars in temperate-zone fruit trees

Directory of Open Access Journals (Sweden)

Alexandre Couto Rodrigues

2005-04-01

Full Text Available As frutíferas de clima temperado apresentam o fenômeno da dormência. Na saída da dormência, há a conversão do amido para açúcares solúveis, como substrato para a retomada de crescimento na primavera. Visando à maior compreensão da fisiologia das plantas em respostas a eventos, como as variações climáticas, estresses e problemas de adaptação, desenvolveu-se este trabalho, no Laboratório de Fisiologia Vegetal da Embrapa Clima Temperado, com o objetivo de descrever uma metodologia para a determinação das concentrações dos açúcares solúveis (frutose, sorbitol, alfa-glicose, beta-glicose e sacarose, em tecidos vegetais de frutíferas, via cromatografia gasosa. O cromatógrafo utilizado para as análises dos açúcares por essa metodologia é o GAS CHROMATOGRAPH e a coluna do tipo Packed Column J. K. de 3,2mm de diâmetro por 2m de comprimento, empacotada com Silicone SE-52 Uniport HP 80/100 mesh. Através da cromatografia gasosa, obtêm-se eficiência e resolução cromatográfica, para análises de açúcares solúveis, sendo, desta forma, vantajoso e executável esse tipo de análise pelo método descrito.The temperate-zone deciduous fruit trees present the phenomenon of dormancy. In that period, there is the conversion of the starch in soluble sugars, as substratum for the resumption of growth in the spring. Seeking to better understanding the physiology of the plants in answers to events as the climatic variations, stresses and adaptation problems, this study was done in the Laboratory of Crop Physiology of Embrapa Temperate Climate, with the objective of describing a methodology for determination of concentrations of the soluble sugars (fructose, sorbitol, alpha-glucose, beta-glucose and sucrose, in tissues of fruit tree, through gaseous chromatography. The chromatograph used for the analyses of the sugars was the GAS CHROMATOGRAPH with the column of the type Packed Column J. K. of 3,2mm of diameter for 2m of length

Climate change impact on groundwater levels in the Guarani Aquifer outcrop zone

Science.gov (United States)

Melo, D. D.; Wendland, E.

2013-12-01

The unsustainable use of groundwater in many countries might cause water availability restrictions in the future. Such issue is likely to worsen due to predicted climate changes for the incoming decades. As numerous studies suggest, aquifers recharge rates will be affected as a result of climate change. The Guarani Aquifer System (GAS) is one of the most important transboundary aquifer in the world, providing drinkable water for millions of people in four South American countries (Brazil, Argentina, Uruguay and Paraguay). Considering the GAS relevance and how its recharge rates might be altered by climatic conditions anomalies, the objective of this work is to assess possible climate changes impacts on groundwater levels in this aquifer outcrop zone. Global Climate Models' (GCM) outputs were used as inputs in a transient flux groundwater model created using the software SPA (Simulation of Process in Aquifers), enabling groundwater table fluctuation to be evaluated under distinct climatic scenarios. Six monitoring wells, located in a representative basin (Ribeirão da Onça basin) inside a GAS outcrop zone (ROB), provided water table measurements between 2004 and 2011 to calibrate the groundwater model. Using observed climatic data, a water budget method was applied to estimate recharge in different types of land uses. Statistically downscaled future climate scenarios were used as inputs for that same recharge model, which provided data for running SPA under those scenarios. The results show that most of the GCMs used here predict temperature arises over 275,15 K and major monthly rainfall mean changes to take place in the dry season. During wet seasons, those means might experience around 50% decrease. The transient model results indicate that water table variations, derived from around 70% of the climate scenarios, would vary below those measured between 2004 and 2011. Among the thirteen GCMs considered in this work, only four of them predicted more extreme

Regional analysis of ground and above-ground climate. Part I. Regional suitability of earth-tempering practices: summary and conclusions. Part II. Bioclimatic data

Energy Technology Data Exchange (ETDEWEB)

Labs, K.

The regional suitability of underground construction as a climate-control technique is discussed with reference to (1) a bioclimatic analysis of long-term weather data for 29 locations in the United States to determine appropriate above-ground climate-control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dewpoint ground temperature comparisons for identifying the relative likelihood of condensation, from one region to another. It is concluded that the suitability of earth tempering as a practice and of specific earth-sheltered design stereotypes varies geographically. While the subsurface almost always provides a thermal advantage on its own terms when compared to above-ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate-control techniques. Also contained in the report are reviews of above- and below-ground climate mapping schemes related to human comfort and architectural design, and a detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 29 locations in the United States. 3 references, 12 figures, 14 tables.

Spatial variability and potential impacts of climate change on flood and debris flow hazard zone mapping and implications for risk management

Directory of Open Access Journals (Sweden)

H. Staffler

2008-06-01

Full Text Available The main goals of this study were to identify the alpine torrent catchments that are sensitive to climatic changes and to assess the robustness of the methods for the elaboration of flood and debris flow hazard zone maps to specific effects of climate changes. In this study, a procedure for the identification and localization of torrent catchments in which the climate scenarios will modify the hazard situation was developed. In two case studies, the impacts of a potential increase of precipitation intensities to the delimited hazard zones were studied.

The identification and localization of the torrent and river catchments, where unfavourable changes in the hazard situation occur, could eliminate speculative and unnecessary measures against the impacts of climate changes like a general enlargement of hazard zones or a general over dimensioning of protection structures for the whole territory. The results showed a high spatial variability of the sensitivity of catchments to climate changes. In sensitive catchments, the sediment management in alpine torrents will meet future challenges due to a higher rate for sediment removal from retention basins. The case studies showed a remarkable increase of the areas affected by floods and debris flow when considering possible future precipitation intensities in hazard mapping. But, the calculated increase in extent of future hazard zones lay within the uncertainty of the methods used today for the delimitation of the hazard zones. Thus, the consideration of the uncertainties laying in the methods for the elaboration of hazard zone maps in the torrent and river catchments sensitive to climate changes would provide a useful instrument for the consideration of potential future climate conditions. The study demonstrated that weak points in protection structures in future will become more important in risk management activities.

From species sensitivity to hypoxia to effect factors modelling in life cycle impact assessment (LCIA)

DEFF Research Database (Denmark)

Cosme, Nuno Miguel Dias; Hauschild, Michael Zwicky

’s sensitivity in five climate zone (polar, subpolar, temperate, subtropical, tropical). Species Sensitivity Distribution (SSD) curves combining DO concentrations and Potentially Affected Fractions (PAF) of species were plotted to estimate hazard concentrations (HC50LOEL) per climate zone, and Effect Factors (EF...

Rainfall distribution and change detection across climatic zones in Nigeria

OpenAIRE

Stephen Bunmi Ogungbenro; Tobi Eniolu Morakinyo

2014-01-01

Nigerian agriculture is mainly rain-fed and basically dependent on the vagaries of weather especially rainfall. Nigeria today has about forty-four (44) weather observation stations which provide measurement of rainfall amount for different locations across the country. Hence, this study investigates change detection in rainfall pattern over each climatic zone of Nigeria. Data were collected for 90 years (1910–1999) period for all the weather observation stations in Nigeria, while a subdivisio...

Evaluating Thermal Comfort in a Naturally Conditioned Office in a Temperate Climate Zone

Directory of Open Access Journals (Sweden)

Andrés Gallardo

2016-07-01

Full Text Available This study aims to determine the optimal approach for evaluating thermal comfort in an office that uses natural ventilation as the main conditioning strategy; the office is located in Quito-Ecuador. The performance of the adaptive model included in CEN Standard EN15251 and the traditional PMV model are compared with reports of thermal environment satisfaction surveys presented simultaneously to all occupants of the office to determine which of the two comfort models is most suitable to evaluate the thermal environment. The results indicate that office occupants have developed some degree of adaptation to the climatic conditions of the city where the office is located (which only demands heating operation, and tend to accept and even prefer lower operative temperatures than those considered optimum by applying the PMV model. This is an indication that occupants of naturally conditioned buildings are usually able to match their comfort temperature to their normal environment. Therefore, the application of the adaptive model included in CEN Standard EN15251 seems like the optimal approach for evaluating thermal comfort in naturally conditioned buildings, because it takes into consideration the adaptive principle that indicates that if a change occurs such as to produce discomfort, people tend to react in ways which restore their comfort.

Design Optimization of a Small-Scale Polygeneration Energy System in Different Climate Zones in Iran

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Sara Ghaem Sigarchian

2018-05-01

Full Text Available Design and performance of polygeneration energy systems are highly influenced by several variables, including the climate zone, which can affect the load profile as well as the availability of renewable energy sources. To investigate the effects, in this study, the design of a polygeneration system for identical residential buildings that are located in three different climate zones in Iran has been investigated. To perform the study, a model has previously developed by the author is used. The performance of the polygeneration system in terms of energy, economy and environment were compared to each other. The results show significant energetic and environmental benefits of the implementation of polygeneration systems in Iran, especially in the building that is located in a hot climate, with a high cooling demand and a low heating demand. Optimal polygeneration system for an identical building has achieved a 27% carbon dioxide emission reduction in the cold climate, while this value is around 41% in the hot climate. However, when considering the price of electricity and gas in the current energy market in Iran, none of the systems are feasible and financial support mechanisms or other incentives are required to promote the application of decentralized polygeneration energy systems.

CANDIDATE PLANETS IN THE HABITABLE ZONES OF KEPLER STARS

International Nuclear Information System (INIS)

Gaidos, Eric

2013-01-01

A key goal of the Kepler mission is the discovery of Earth-size transiting planets in ''habitable zones'' where stellar irradiance maintains a temperate climate on an Earth-like planet. Robust estimates of planet radius and irradiance require accurate stellar parameters, but most Kepler systems are faint, making spectroscopy difficult and prioritization of targets desirable. The parameters of 2035 host stars were estimated by Bayesian analysis and the probabilities p HZ that 2738 candidate or confirmed planets orbit in the habitable zone were calculated. Dartmouth Stellar Evolution Program models were compared to photometry from the Kepler Input Catalog, priors for stellar mass, age, metallicity and distance, and planet transit duration. The analysis yielded probability density functions for calculating confidence intervals of planet radius and stellar irradiance, as well as p HZ . Sixty-two planets have p HZ > 0.5 and a most probable stellar irradiance within habitable zone limits. Fourteen of these have radii less than twice the Earth; the objects most resembling Earth in terms of radius and irradiance are KOIs 2626.01 and 3010.01, which orbit late K/M-type dwarf stars. The fraction of Kepler dwarf stars with Earth-size planets in the habitable zone (η ⊕ ) is 0.46, with a 95% confidence interval of 0.31-0.64. Parallaxes from the Gaia mission will reduce uncertainties by more than a factor of five and permit definitive assignments of transiting planets to the habitable zones of Kepler stars.

Cover crops mitigate direct greenhouse gases balance but reduce drainage under climate change scenarios in temperate climate with dry summers.

Science.gov (United States)

Tribouillois, Hélène; Constantin, Julie; Justes, Eric

2018-02-14

Cover crops provide ecosystem services such as storing atmospheric carbon in soils after incorporation of their residues. Cover crops also influence soil water balance, which can be an issue in temperate climates with dry summers as for example in southern France and Europe. As a consequence, it is necessary to understand cover crops' long-term influence on greenhouse gases (GHG) and water balances to assess their potential to mitigate climate change in arable cropping systems. We used the previously calibrated and validated soil-crop model STICS to simulate scenarios of cover crop introduction to assess their influence on rainfed and irrigated cropping systems and crop rotations distributed among five contrasted sites in southern France from 2007 to 2052. Our results showed that cover crops can improve mean direct GHG balance by 315 kg CO 2 e ha -1  year -1 in the long term compared to that of bare soil. This was due mainly to an increase in carbon storage in the soil despite a slight increase in N 2 O emissions which can be compensated by adapting fertilization. Cover crops also influence the water balance by reducing mean annual drainage by 20 mm/year but increasing mean annual evapotranspiration by 20 mm/year compared to those of bare soil. Using cover crops to improve the GHG balance may help to mitigate climate change by decreasing CO 2 e emitted in cropping systems which can represent a decrease from 4.5% to 9% of annual GHG emissions of the French agriculture and forestry sector. However, if not well managed, they also could create water management issues in watersheds with shallow groundwater. Relationships between cover crop biomass and its influence on several variables such as drainage, carbon sequestration, and GHG emissions could be used to extend our results to other conditions to assess the cover crops' influence in a wider range of areas. © 2018 John Wiley & Sons Ltd.

Disaggregating Tropical Disease Prevalence by Climatic and Vegetative Zones within Tropical West Africa.

Science.gov (United States)

Beckley, Carl S; Shaban, Salisu; Palmer, Guy H; Hudak, Andrew T; Noh, Susan M; Futse, James E

2016-01-01

Tropical infectious disease prevalence is dependent on many socio-cultural determinants. However, rainfall and temperature frequently underlie overall prevalence, particularly for vector-borne diseases. As a result these diseases have increased prevalence in tropical as compared to temperate regions. Specific to tropical Africa, the tendency to incorrectly infer that tropical diseases are uniformly prevalent has been partially overcome with solid epidemiologic data. This finer resolution data is important in multiple contexts, including understanding risk, predictive value in disease diagnosis, and population immunity. We hypothesized that within the context of a tropical climate, vector-borne pathogen prevalence would significantly differ according to zonal differences in rainfall, temperature, relative humidity and vegetation condition. We then determined if these environmental data were predictive of pathogen prevalence. First we determined the prevalence of three major pathogens of cattle, Anaplasma marginale, Babesia bigemina and Theileria spp, in the three vegetation zones where cattle are predominantly raised in Ghana: Guinea savannah, semi-deciduous forest, and coastal savannah. The prevalence of A. marginale was 63%, 26% for Theileria spp and 2% for B. bigemina. A. marginale and Theileria spp. were significantly more prevalent in the coastal savannah as compared to either the Guinea savanna or the semi-deciduous forest, supporting acceptance of the first hypothesis. To test the predictive power of environmental variables, the data over a three year period were considered in best subsets multiple linear regression models predicting prevalence of each pathogen. Corrected Akaike Information Criteria (AICc) were assigned to the alternative models to compare their utility. Competitive models for each response were averaged using AICc weights. Rainfall was most predictive of pathogen prevalence, and EVI also contributed to A. marginale and B. bigemina prevalence

Disaggregating Tropical Disease Prevalence by Climatic and Vegetative Zones within Tropical West Africa.

Directory of Open Access Journals (Sweden)

Carl S Beckley

Full Text Available Tropical infectious disease prevalence is dependent on many socio-cultural determinants. However, rainfall and temperature frequently underlie overall prevalence, particularly for vector-borne diseases. As a result these diseases have increased prevalence in tropical as compared to temperate regions. Specific to tropical Africa, the tendency to incorrectly infer that tropical diseases are uniformly prevalent has been partially overcome with solid epidemiologic data. This finer resolution data is important in multiple contexts, including understanding risk, predictive value in disease diagnosis, and population immunity. We hypothesized that within the context of a tropical climate, vector-borne pathogen prevalence would significantly differ according to zonal differences in rainfall, temperature, relative humidity and vegetation condition. We then determined if these environmental data were predictive of pathogen prevalence. First we determined the prevalence of three major pathogens of cattle, Anaplasma marginale, Babesia bigemina and Theileria spp, in the three vegetation zones where cattle are predominantly raised in Ghana: Guinea savannah, semi-deciduous forest, and coastal savannah. The prevalence of A. marginale was 63%, 26% for Theileria spp and 2% for B. bigemina. A. marginale and Theileria spp. were significantly more prevalent in the coastal savannah as compared to either the Guinea savanna or the semi-deciduous forest, supporting acceptance of the first hypothesis. To test the predictive power of environmental variables, the data over a three year period were considered in best subsets multiple linear regression models predicting prevalence of each pathogen. Corrected Akaike Information Criteria (AICc were assigned to the alternative models to compare their utility. Competitive models for each response were averaged using AICc weights. Rainfall was most predictive of pathogen prevalence, and EVI also contributed to A. marginale and B

The effects of warming and nitrogen addition on soil nitrogen cycling in a temperate grassland, northeastern China.

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Lin-Na Ma

Full Text Available Both climate warming and atmospheric nitrogen (N deposition are predicted to affect soil N cycling in terrestrial biomes over the next century. However, the interactive effects of warming and N deposition on soil N mineralization in temperate grasslands are poorly understood.A field manipulation experiment was conducted to examine the effects of warming and N addition on soil N cycling in a temperate grassland of northeastern China from 2007 to 2009. Soil samples were incubated at a constant temperature and moisture, from samples collected in the field. The results showed that both warming and N addition significantly stimulated soil net N mineralization rate and net nitrification rate. Combined warming and N addition caused an interactive effect on N mineralization, which could be explained by the relative shift of soil microbial community structure because of fungal biomass increase and strong plant uptake of added N due to warming. Irrespective of strong intra- and inter-annual variations in soil N mineralization, the responses of N mineralization to warming and N addition did not change during the three growing seasons, suggesting independence of warming and N responses of N mineralization from precipitation variations in the temperate grassland.Interactions between climate warming and N deposition on soil N cycling were significant. These findings will improve our understanding on the response of soil N cycling to the simultaneous climate change drivers in temperate grassland ecosystem.

Impacts of short-term heatwaves on sun-induced chlorophyll fluorescence(SiF) in temperate tree species

Science.gov (United States)

Wang, F.; Gu, L.; Guha, A.; Han, J.; Warren, J.

2017-12-01

The current projections for global climate change forecast an increase in the intensity and frequency of extreme climatic events, such as droughts and short-term heat waves. Understanding the effects of short-term heat wave on photosynthesis process is of critical importance to predict global impacts of extreme weather event on vegetation. The diurnal and seasonal characteristics of SIF emitted from natural vegetation, e.g., forest and crop, have been studied at the ecosystem-scale, regional-scale and global-scale. However, the detailed response of SIF from different plant species under extremely weather event, especially short-term heat wave, have not been reported. The purpose of this study was to study the response of solar-induced chlorophyll fluorescence, gas exchange and continuous fluorescence at leaf scale for different temperate tree species. The short-term heatwave experiment was conducted using plant growth chamber (CMP6050, Conviron Inc., Canada). We developed an advanced spectral fitting method to obtain the plant SIF in the plant growth chamber. We compared SIF variation among different wavelength and chlorophyll difference among four temperate tree species. The diurnal variation of SIF signals at leaf-scales for temperate tree species are different under heat stress. The SIF response at leaf-scales and their difference for four temperate tree species are different during a cycle of short-term heatwave stress. We infer that SIF be used as a measure of heat tolerance for temperate tree species.

Diversity and abundance of photosynthetic sponges in temperate Western Australia

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Brümmer Franz

2009-02-01

Full Text Available Abstract Background Photosynthetic sponges are important components of reef ecosystems around the world, but are poorly understood. It is often assumed that temperate regions have low diversity and abundance of photosynthetic sponges, but to date no studies have investigated this question. The aim of this study was to compare the percentages of photosynthetic sponges in temperate Western Australia (WA with previously published data on tropical regions, and to determine the abundance and diversity of these associations in a range of temperate environments. Results We sampled sponges on 5 m belt transects to determine the percentage of photosynthetic sponges and identified at least one representative of each group of symbionts using 16S rDNA sequencing together with microscopy techniques. Our results demonstrate that photosynthetic sponges are abundant in temperate WA, with an average of 63% of sponge individuals hosting high levels of photosynthetic symbionts and 11% with low to medium levels. These percentages of photosynthetic sponges are comparable to those found on tropical reefs and may have important implications for ecosystem function on temperate reefs in other areas of the world. A diverse range of symbionts sometimes occurred within a small geographic area, including the three "big" cyanobacterial clades, Oscillatoria spongeliae, "Candidatus Synechococcus spongiarum" and Synechocystis species, and it appears that these clades all occur in a wide range of sponges. Additionally, spongin-permeating red algae occurred in at least 7 sponge species. This study provides the first investigation of the molecular phylogeny of rhodophyte symbionts in sponges. Conclusion Photosynthetic sponges are abundant and diverse in temperate WA, with comparable percentages of photosynthetic to non-photosynthetic sponges to tropical zones. It appears that there are three common generalist clades of cyanobacterial symbionts of sponges which occur in a wide

Trichinella in arctic, subarctic and temperate regions

DEFF Research Database (Denmark)

Kapel, C. M O

1997-01-01

The transmission and occurrence of Trichinella spp according to the zoogeography of different climatic conditions, socioeconomy and human activity are discussed. Comparing arctic, subarctic and temperate regions, it appears that the species of Trichinella present, the composition of the fauna...... and the human activity are all very important interacting factors affecting epidemiology. In Greenland, where only sylvatic trichinellosis is present, the high prevalence in wildlife appears closely connected with polar bear hunting. In the Scandinavian countries, the prevalence of both sylvatic and domestic...

Soil quality differences in a mature alley cropping system in temperate North America

Science.gov (United States)

Alley cropping in agroforestry practices has been shown to improve soil quality, however information on long-term effects (>10 years) of alley cropping on soils in the temperate zone is very limited. The objective of this study was to examine effects of management, landscape, and soil depth on soil...

Drought timing and local climate determine the sensitivity of eastern temperate forests to drought.

Science.gov (United States)

D'Orangeville, Loïc; Maxwell, Justin; Kneeshaw, Daniel; Pederson, Neil; Duchesne, Louis; Logan, Travis; Houle, Daniel; Arseneault, Dominique; Beier, Colin M; Bishop, Daniel A; Druckenbrod, Daniel; Fraver, Shawn; Girard, François; Halman, Joshua; Hansen, Chris; Hart, Justin L; Hartmann, Henrik; Kaye, Margot; Leblanc, David; Manzoni, Stefano; Ouimet, Rock; Rayback, Shelly; Rollinson, Christine R; Phillips, Richard P

2018-02-20

Projected changes in temperature and drought regime are likely to reduce carbon (C) storage in forests, thereby amplifying rates of climate change. While such reductions are often presumed to be greatest in semi-arid forests that experience widespread tree mortality, the consequences of drought may also be important in temperate mesic forests of Eastern North America (ENA) if tree growth is significantly curtailed by drought. Investigations of the environmental conditions that determine drought sensitivity are critically needed to accurately predict ecosystem feedbacks to climate change. We matched site factors with the growth responses to drought of 10,753 trees across mesic forests of ENA, representing 24 species and 346 stands, to determine the broad-scale drivers of drought sensitivity for the dominant trees in ENA. Here we show that two factors-the timing of drought, and the atmospheric demand for water (i.e., local potential evapotranspiration; PET)-are stronger drivers of drought sensitivity than soil and stand characteristics. Drought-induced reductions in tree growth were greatest when the droughts occurred during early-season peaks in radial growth, especially for trees growing in the warmest, driest regions (i.e., highest PET). Further, mean species trait values (rooting depth and ψ 50 ) were poor predictors of drought sensitivity, as intraspecific variation in sensitivity was equal to or greater than interspecific variation in 17 of 24 species. From a general circulation model ensemble, we find that future increases in early-season PET may exacerbate these effects, and potentially offset gains in C uptake and storage in ENA owing to other global change factors. © 2018 John Wiley & Sons Ltd.

Comparing the sensitivity of permafrost and marine gas hydrate to climate warming

International Nuclear Information System (INIS)

Taylor, A.E.; Dallimore, S.R.; Hyndman, R.D.; Wright, F.

2005-01-01

The sensitivity of Arctic subpermafrost gas hydrate at the Mallik borehole was compared to temperate marine gas hydrate located offshore southwestern Canada. In particular, a finite element geothermal model was used to determine the sensitivity to the end of the ice age, and contemporary climate warming of a 30 m thick methane hydrate layer lying at the base of a gas hydrate stability zone prior to 13.5 kiloannum (ka) before present (BP). It was suggested that the 30 m gas-hydrate-bearing layer would have disappeared by now, according to the thermal signal alone. However, the same gas-hydrate-bearing layer underlying permafrost would persist until at least 4 ka after present, even with contemporary climate warming. The longer time for subpermafrost gas hydrate comes from the thawing pore ice at the base of permafrost, at the expense of dissociation of the deeper gas hydrate. The dissociation of underlying gas hydrate from climate surface warming is buffered by the overlying permafrost

The Need for Temperance

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Karl Inge Tangen

2015-11-01

Full Text Available This article explores how temperance as a virtue relates to organizational leadership. The study begins with a short survey of classical Greek and Christian notions of temperance before proceeding to ex-plore temperance in relation to self-leadership, visionary and strategic leadership, and relational lead-ership. The final part of the article offers reflections on how temperance might be cultivated from a theological perspective. Temperance is understood not only as sound thinking but also as embodied self-control and active patience. On the level of self-leadership, it is argued that temperance enables the leader to establish forms of integrity that protect the leader’s self from chaos and destruction. Moreover, temperance may also nurture focused visionary leadership that accepts ethical limits and has an eye to the common good. The study also suggests that organizations should cultivate a culture of strategic discipline that is capable of realizing such visions. On the interpersonal level, temperance is viewed as critical in terms of enabling leaders to treat co-workers with respect and wisdom and han-dle conflict with consideration. Finally, is argued that that the cultivation of temperance is not a one-way street from the inside to the outside or a subordination of feelings to reason but rather a very complex process that includes interpersonal humility, finds vision in an encounter with the good, and yet remains a personal responsibility.

Chilling and heat requirements for flowering in temperate fruit trees.

Science.gov (United States)

Guo, Liang; Dai, Junhu; Ranjitkar, Sailesh; Yu, Haiying; Xu, Jianchu; Luedeling, Eike

2014-08-01

Climate change has affected the rates of chilling and heat accumulation, which are vital for flowering and production, in temperate fruit trees, but few studies have been conducted in the cold-winter climates of East Asia. To evaluate tree responses to variation in chill and heat accumulation rates, partial least squares regression was used to correlate first flowering dates of chestnut (Castanea mollissima Blume) and jujube (Zizyphus jujube Mill.) in Beijing, China, with daily chill and heat accumulation between 1963 and 2008. The Dynamic Model and the Growing Degree Hour Model were used to convert daily records of minimum and maximum temperature into horticulturally meaningful metrics. Regression analyses identified the chilling and forcing periods for chestnut and jujube. The forcing periods started when half the chilling requirements were fulfilled. Over the past 50 years, heat accumulation during tree dormancy increased significantly, while chill accumulation remained relatively stable for both species. Heat accumulation was the main driver of bloom timing, with effects of variation in chill accumulation negligible in Beijing’s cold-winter climate. It does not seem likely that reductions in chill will have a major effect on the studied species in Beijing in the near future. Such problems are much more likely for trees grown in locations that are substantially warmer than their native habitats, such as temperate species in the subtropics and tropics.

Chilling and heat requirements for flowering in temperate fruit trees

Science.gov (United States)

Guo, Liang; Dai, Junhu; Ranjitkar, Sailesh; Yu, Haiying; Xu, Jianchu; Luedeling, Eike

2014-08-01

Climate change has affected the rates of chilling and heat accumulation, which are vital for flowering and production, in temperate fruit trees, but few studies have been conducted in the cold-winter climates of East Asia. To evaluate tree responses to variation in chill and heat accumulation rates, partial least squares regression was used to correlate first flowering dates of chestnut ( Castanea mollissima Blume) and jujube ( Zizyphus jujube Mill.) in Beijing, China, with daily chill and heat accumulation between 1963 and 2008. The Dynamic Model and the Growing Degree Hour Model were used to convert daily records of minimum and maximum temperature into horticulturally meaningful metrics. Regression analyses identified the chilling and forcing periods for chestnut and jujube. The forcing periods started when half the chilling requirements were fulfilled. Over the past 50 years, heat accumulation during tree dormancy increased significantly, while chill accumulation remained relatively stable for both species. Heat accumulation was the main driver of bloom timing, with effects of variation in chill accumulation negligible in Beijing's cold-winter climate. It does not seem likely that reductions in chill will have a major effect on the studied species in Beijing in the near future. Such problems are much more likely for trees grown in locations that are substantially warmer than their native habitats, such as temperate species in the subtropics and tropics.

Variation in carbon storage and its distribution by stand age and forest type in boreal and temperate forests in northeastern China.

Science.gov (United States)

Wei, Yawei; Li, Maihe; Chen, Hua; Lewis, Bernard J; Yu, Dapao; Zhou, Li; Zhou, Wangming; Fang, Xiangmin; Zhao, Wei; Dai, Limin

2013-01-01

The northeastern forest region of China is an important component of total temperate and boreal forests in the northern hemisphere. But how carbon (C) pool size and distribution varies among tree, understory, forest floor and soil components, and across stand ages remains unclear. To address this knowledge gap, we selected three major temperate and two major boreal forest types in northeastern (NE) China. Within both forest zones, we focused on four stand age classes (young, mid-aged, mature and over-mature). Results showed that total C storage was greater in temperate than in boreal forests, and greater in older than in younger stands. Tree biomass C was the main C component, and its contribution to the total forest C storage increased with increasing stand age. It ranged from 27.7% in young to 62.8% in over-mature stands in boreal forests and from 26.5% in young to 72.8% in over-mature stands in temperate forests. Results from both forest zones thus confirm the large biomass C storage capacity of old-growth forests. Tree biomass C was influenced by forest zone, stand age, and forest type. Soil C contribution to total forest C storage ranged from 62.5% in young to 30.1% in over-mature stands in boreal and from 70.1% in young to 26.0% in over-mature in temperate forests. Thus soil C storage is a major C pool in forests of NE China. On the other hand, understory and forest floor C jointly contained less than 13% and forests respectively, and thus play a minor role in total forest C storage in NE China.

Suitability Analysis and Projected Climate Change Impact on Banana and Coffee Production Zones in Nepal

Science.gov (United States)

Sujakhu, Nani M.; Merz, Juerg; Kindt, Roeland; Xu, Jianchu; Matin, Mir A.; Ali, Mostafa; Zomer, Robert J.

2016-01-01

The Government of Nepal has identified opportunities in agricultural commercialization, responding to a growing internal demand and expansion of export markets to reduce the immense trade deficit. Several cash crops, including coffee and bananas, have been identified in the recently approved Agriculture Development Strategy. Both of these crops have encouraged smallholder farmers to convert their subsistence farming practices to more commercial cultivation. Identification of suitable agro-ecological zones and understanding climate-related issues are important for improved production and livelihoods of smallholder farmers. Here, the suitability of coffee and banana crops is analyzed for different agro-ecological zones represented by Global Environmental Stratification (GEnS). Future shifts in these suitability zones are also predicted. Plantation sites in Nepal were geo-referenced and used as input in species distribution modelling. The multi-model ensemble model suggests that climate change will reduce the suitable growing area for coffee by about 72% across the selected emission scenarios from now to 2050. Impacts are low for banana growing, with a reduction in suitability by about 16% by 2050. Bananas show a lot of potential for playing an important role in Nepal as a sustainable crop in the context of climate change, as this study indicates that the amount of area suited to banana growing will grow by 40% by 2050. Based on our analysis we recommend possible new locations for coffee plantations and one method for mitigating climate change-related problems on existing plantations. These findings are expected to support planning and policy dialogue for mitigation and support better informed and scientifically based decision-making relating to these two crops. PMID:27689354

Soil quality indicators of a mature alley-cropping agroforestry system in temperate North America

Science.gov (United States)

Although agroforestry practices are believed to improve soil quality, reports on long-term effects of alley cropping on soils within agroforestry in the temperate zone are limited. The objective of this study was to examine effects of management, landscape, and soil depth of an established agrofores...

Thermal Regime of A Deep Temperate Lake and Its Response to Climate Change: Lake Kuttara, Japan

Directory of Open Access Journals (Sweden)

Kazuhisa A. Chikita

2018-02-01

Full Text Available A deep temperate lake, Lake Kuttara, Hokkaido, Japan (148 m deep at maximum was completely ice-covered every winter in the 20th century. However, ice-free conditions of the lake over winter occurred three times in the 21st century, which is probably due to global warming. In order to understand how thermal regime of the lake responds to climate change, a change in lake mean water temperature from the heat storage change was calculated by integrating observed water temperature over water depths and by numerical calculation of heat budget components based on hydrometeorological data. As a result, a temporal variation of lake mean water temperature from the heat budget calculation was very reasonable to that from the observed water temperature (determination coefficient R2 = 0.969. The lowest lake mean temperature for non-freeze was then evaluated at −1.87 °C, referring to the zero level at 6.80 °C. The 1978–2017 data at a meteorological station near Kuttara indicated that there are significant (less than 5% level long-term trends for air temperature (+0.024 °C/year and wind speed (−0.010 m/s/year. In order to evaluate the effects of climate change on freeze-up patterns, a sensitivity analysis was carried out for the calculated lake mean water temperature. It is noted that, after two decades, the lake could be ice-free once per every two years.

Analysis of yield and plant traits of oilseed rape (Brassica napus L. cultivated in temperate region in light of the possibilities of sowing in arid areas

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Tadeusz Zając

2016-12-01

Full Text Available This work is a review of selected literature on the species of Brassica with the greatest economic significance. Oilseed rape (Brassica napus ssp. oleifera currently ranks third worldwide among oilseed crops used for oil production and is the most important in the temperate zone. The manifold uses of rape include not only human consumption of oil, but also the use of post-extraction meal to feed livestock as well as industrial applications as a source of bioenergy or cellulose. The improvement in the economic position of rape among crop plants is also due to the doubling of its yield between 1970 and 2009; the average annual increase in seed yield worldwide was 27 kg ha−1 yr−1. The yield level in Europe exceeds the average yields achieved in the world, particularly in Asia. Recently, the cultivation of oilseed rape was started on a relatively large acreage in Iran where the yield amounted 2.1 t ha−1, exceeding the yields of China and India. In Poland, the acreage of oilseed rape cultivation between 1965 and 2013 increased 3–4 times, and during this period the annual increase in seed yield was 29 kg ha−1 yr−1. Under the field conditions of the temperate climate zone, winter oilseed rape yield is mainly determined by agro-climatic conditions during the growing period, the level of nitrogen fertilization, and the production potential of varieties, which is currently highest in hybrids. There is a noticeable tendency of hybrids towards formation of more siliques by individual oilseed plants. Different production categories of plants appear in a rape crop. Semi-dwarf varieties of winter rapeseed are distinguished by greater silique density, particularly on the main shoot. Moreover, these hybrids are characterized by faster growth of the root system, which enables them to take up nitrogen from the soil more efficiently.

Possible responses of northern peatlands to climate change in the zone of discontinuous permafrost, Manitoba, Canada

Energy Technology Data Exchange (ETDEWEB)

Bubier, J L [New Hampshire Univ., Durham, NH (United States). Inst. for the Study of Earth, Oceans, and Space; Moore, T R [McGill Univ., Montreal (Canada). Geography Dept.

1997-12-31

More than half of the world`s peatlands occur in the boreal zone (45 - 60 deg C N. lat), a region which global climate models predict will experience large changes in temperature and precipitation with increasing atmospheric CO{sub 2} concentrations. The northern part of the boreal zone is characterised by discontinuous permafrost, an area that is particularly sensitive to climate change with the possible degradation and thawing of frozen peat. Peatlands are large sources of atmospheric methane (CH{sub 4}), an important greenhouse gas. Yet few measurements of methane have been conducted in discontinuous permafrost environments. As part of the Boreal Ecosystem-Atmosphere Study (BOREAS), CH{sub 4} flux was measured in a diverse peatland complex (bogs, fens, peat plateaus, and collapse scars), representing the complete range of temperature, moisture, and plant community gradients found in northern peatlands. The measurement period May to September 1994 was one of the warmest and driest seasons on record, which provided an opportunity to observe the short-term responses of different parts of the peatland ecosystem to a warmer and drier climate as an analog to predicted climate change in the region. (5 refs.)

Possible responses of northern peatlands to climate change in the zone of discontinuous permafrost, Manitoba, Canada

Energy Technology Data Exchange (ETDEWEB)

Bubier, J.L. [New Hampshire Univ., Durham, NH (United States). Inst. for the Study of Earth, Oceans, and Space; Moore, T.R. [McGill Univ., Montreal (Canada). Geography Dept.

1996-12-31

More than half of the world`s peatlands occur in the boreal zone (45 - 60 deg C N. lat), a region which global climate models predict will experience large changes in temperature and precipitation with increasing atmospheric CO{sub 2} concentrations. The northern part of the boreal zone is characterised by discontinuous permafrost, an area that is particularly sensitive to climate change with the possible degradation and thawing of frozen peat. Peatlands are large sources of atmospheric methane (CH{sub 4}), an important greenhouse gas. Yet few measurements of methane have been conducted in discontinuous permafrost environments. As part of the Boreal Ecosystem-Atmosphere Study (BOREAS), CH{sub 4} flux was measured in a diverse peatland complex (bogs, fens, peat plateaus, and collapse scars), representing the complete range of temperature, moisture, and plant community gradients found in northern peatlands. The measurement period May to September 1994 was one of the warmest and driest seasons on record, which provided an opportunity to observe the short-term responses of different parts of the peatland ecosystem to a warmer and drier climate as an analog to predicted climate change in the region. (5 refs.)

Database of Low-e Storm Window Energy Performance across U.S. Climate Zones

Energy Technology Data Exchange (ETDEWEB)

Culp, Thomas D.; Cort, Katherine A.

2014-09-04

This is an update of a report that describes process, assumptions, and modeling results produced Create a Database of U.S. Climate-Based Analysis for Low-E Storm Windows. The scope of the overall effort is to develop a database of energy savings and cost effectiveness of low-E storm windows in residential homes across a broad range of U.S. climates using the National Energy Audit Tool (NEAT) and RESFEN model calculations. This report includes a summary of the results, NEAT and RESFEN background, methodology, and input assumptions, and an appendix with detailed results and assumptions by cliamte zone.

Ecological traps in shallow coastal waters-Potential effect of heat-waves in tropical and temperate organisms.

Directory of Open Access Journals (Sweden)

Catarina Vinagre

Full Text Available Mortality of fish has been reported in tide pools during warm days. That means that tide pools are potential ecological traps for coastal organisms, which happen when environmental changes cause maladaptive habitat selection. Heat-waves are predicted to increase in intensity, duration and frequency, making it relevant to investigate the role of tide pools as traps for coastal organisms. However, heat waves can also lead to acclimatization. If organisms undergo acclimatization prior to being trapped in tide pools, their survival chances may increase. Common tide pool species (46 species in total were collected at a tropical and a temperate area and their upper thermal limits estimated. They were maintained for 10 days at their mean summer sea surface temperature +3°C, mimicking a heat-wave. Their upper thermal limits were estimated again, after this acclimation period, to calculate each species' acclimation response. The upper thermal limits of the organisms were compared to the temperatures attained by tide pool waters to investigate if 1 tide pools could be considered ecological traps and 2 if the increase in upper thermal limits elicited by the acclimation period could make the organisms less vulnerable to this threat. Tropical tide pools were found to be ecological traps for an important number of common coastal species, given that they can attain temperatures higher than the upper thermal limits of most of those species. Tide pools are not ecological traps in temperate zones. Tropical species have higher thermal limits than temperate species, but lower acclimation response, that does not allow them to survive the maximum habitat temperature of tropical tide pools. This way, tropical coastal organisms seem to be, not only more vulnerable to climate warming per se, but also to an increase in the ecological trap effect of tide pools.

Energy Savings of Low-E Storm Windows and Panels across US Climate Zones

Energy Technology Data Exchange (ETDEWEB)

Culp, Thomas D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cort, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-10-01

This report builds off of previous modeling work related to low-e storm windows used to create a "Database of U.S. Climate-Based Analysis for Low-E Storm Windows." This work updates similar studies using new fuel costs and examining the separate contributions of reduced air leakage and reduced coefficients of overall heat transfer and solar heat gain. In this report we examine the energy savings and cost effectiveness of low-E storm windows in residential homes across a broad range of U.S. climates, excluding the impact from infiltration reductions, which tend to vary using the National Energy Audit Tool (NEAT) and RESFEN model calculations. This report includes a summary of the results, NEAT and RESFEN background, methodology, and input assumptions, and an appendix with detailed results and assumptions by climate zone.

Potential for thermal tolerance to mediate climate change effects on three members of a cool temperate lizard genus, Niveoscincus.

Science.gov (United States)

Caldwell, Amanda J; While, Geoffrey M; Beeton, Nicholas J; Wapstra, Erik

2015-08-01

Climatic changes are predicted to be greater in higher latitude and mountainous regions but species specific impacts are difficult to predict. This is partly due to inter-specific variance in the physiological traits which mediate environmental temperature effects at the organismal level. We examined variation in the critical thermal minimum (CTmin), critical thermal maximum (CTmax) and evaporative water loss rates (EWL) of a widespread lowland (Niveoscincus ocellatus) and two range restricted highland (N. microlepidotus and N. greeni) members of a cool temperate Tasmanian lizard genus. The widespread lowland species had significantly higher CTmin and CTmax and significantly lower EWL than both highland species. Implications of inter-specific variation in thermal tolerance for activity were examined under contemporary and future climate change scenarios. Instances of air temperatures below CTmin were predicted to decline in frequency for the widespread lowland and both highland species. Air temperatures of high altitude sites were not predicted to exceed the CTmax of either highland species throughout the 21st century. In contrast, the widespread lowland species is predicted to experience air temperatures in excess of CTmax on 1 or 2 days by three of six global circulation models from 2068-2096. To estimate climate change effects on activity we reran the thermal tolerance models using minimum and maximum temperatures selected for activity. A net gain in available activity time was predicted under climate change for all three species; while air temperatures were predicted to exceed maximum temperatures selected for activity with increasing frequency, the change was not as great as the predicted decline in air temperatures below minimum temperatures selected for activity. We hypothesise that the major effect of rising air temperatures under climate change is an increase in available activity period for both the widespread lowland and highland species. The

Short-term utilization of carbon by the soil microbial community under future climatic conditions in a temperate heathland

DEFF Research Database (Denmark)

Reinsch, Sabine; Michelsen, Anders; Sárossy, Zsuzsa

2014-01-01

An in-situ13C pulse-labeling experiment was carried out in a temperate heath/grassland to study the impacts of elevated CO2 concentration (510ppm), prolonged summer droughts (annual exclusion of 7.6±0.8%) and increased temperature (~1°C) on belowground carbon (C) utilization. Recently assimilated C...... (13C from the pulse-label) was traced into roots, soil and microbial biomass 1, 2 and 8 days after pulse-labeling. The importance of the microbial community in C utilization was investigated using 13C enrichment patterns in different microbial functional groups on the basis of phospholipid fatty acid...... (PLFA) biomarker profiles. Climate treatments did not affect microbial abundance in soil or rhizosphere fractions in terms of total PLFA-C concentration. Elevated CO2 significantly reduced the abundance of gram-negative bacteria (17:0cy), but did not affect the abundance of decomposers (fungi...

Coastal zone

International Nuclear Information System (INIS)

2002-01-01

The report entitled Climate Change Impacts and Adaptation : A Canadian Perspective, presents a summary of research regarding the impacts of climate change on key sectors over the past five years as it relates to Canada. This chapter on the coastal zone focuses on the impact of climate change on Canada's marine and Great Lakes coasts with tips on how to deal with the impacts associated with climate change in sensitive environments. This report is aimed at the sectors that will be most affected by adaptation decisions in the coastal zone, including fisheries, tourism, transportation and water resources. The impact of climate change in the coastal zone may include changes in water levels, wave patterns, storm surges, and thickness of seasonal ice cover. The Intergovernmental Panel on Climate Change projects global average sea level will rise between 9 and 88 centimetres between 1990 to 2100, but not all areas of Canada will experience the same rate of future sea level change. The main physical impact would be shoreline change that could result in a range of biophysical and socio-economic impacts, some beneficial, some negative. The report focuses on issues related to infrastructure and communities in coastal regions. It is noted that appropriate human adaptation will play a vital role in reducing the extent of potential impacts by decreasing the vulnerability of average zone to climate change. The 3 main trends in coastal adaptation include: (1) increase in soft protection, retreat and accommodation, (2) reliance on technology such as geographic information systems to manage information, and (3) awareness of the need for coastal adaptation that is appropriate for local conditions. 61 refs., 7 figs

Phylogeography of Japanese encephalitis virus: genotype is associated with climate.

Directory of Open Access Journals (Sweden)

Amy J Schuh

Full Text Available The circulation of vector-borne zoonotic viruses is largely determined by the overlap in the geographical distributions of virus-competent vectors and reservoir hosts. What is less clear are the factors influencing the distribution of virus-specific lineages. Japanese encephalitis virus (JEV is the most important etiologic agent of epidemic encephalitis worldwide, and is primarily maintained between vertebrate reservoir hosts (avian and swine and culicine mosquitoes. There are five genotypes of JEV: GI-V. In recent years, GI has displaced GIII as the dominant JEV genotype and GV has re-emerged after almost 60 years of undetected virus circulation. JEV is found throughout most of Asia, extending from maritime Siberia in the north to Australia in the south, and as far as Pakistan to the west and Saipan to the east. Transmission of JEV in temperate zones is epidemic with the majority of cases occurring in summer months, while transmission in tropical zones is endemic and occurs year-round at lower rates. To test the hypothesis that viruses circulating in these two geographical zones are genetically distinct, we applied Bayesian phylogeographic, categorical data analysis and phylogeny-trait association test techniques to the largest JEV dataset compiled to date, representing the envelope (E gene of 487 isolates collected from 12 countries over 75 years. We demonstrated that GIII and the recently emerged GI-b are temperate genotypes likely maintained year-round in northern latitudes, while GI-a and GII are tropical genotypes likely maintained primarily through mosquito-avian and mosquito-swine transmission cycles. This study represents a new paradigm directly linking viral molecular evolution and climate.

STUDY THE MORPHOLOGY OF ASIMINA TRILOBA (L. DUNAL FRUITS AND SEEDS OBTAINED IN THE TRANSYLVANIA REGION OF ROMANIA

Directory of Open Access Journals (Sweden)

Beatrice Agneta Szilagyi

2016-07-01

Full Text Available The fruit tree Asimina triloba (L. Dunal originates in the temperate zones of North America. Its fruits are edible and have great nutritional value. The fruits' commercial potential contributes to a growing demand for information about this plant in Romania. A series of morphological observations were performed on the fruits and seeds of Asimina plants adapted to the temperate climate of the Transylvania zone of Romania.

Development and Climate Change in Uruguay. Focus on Coastal Zones, Agriculture and Forestry

International Nuclear Information System (INIS)

Agrawala, S.; Moehner, A.; Gagnon-Lebrun, F.; Van Aalst, M.; Smith, J.; Hagenstad, M.; Baethgen, W.E.; Martino, D.L.; Lorenzo, E.

2004-01-01

This document is an output from the OECD Development and Climate Change project, an activity jointly overseen by the EPOC Working Party on Global and Structural Policies (WPGSP), and the DAC Network on Environment and Development Co-operation (ENVIRONET). The overall objective of the project is to provide guidance on how to mainstream responses to climate change within economic development planning and assistance policies, with natural resource management as an overarching theme. This report presents the integrated case study for Tanzania carried out under an OECD project on Development and Climate Change. This report presents the integrated case study for Uruguay carried out under an OECD project on Development and Climate Change. The report is structured around a three-tiered framework. First, recent climate trends and climate change scenarios for Uruguay are assessed and key sectoral impacts are identified and ranked along multiple indicators to establish priorities for adaptation. Second, donor portfolios are analyzed to examine the proportion of development assistance activities affected by climate risks. A desk analysis of donor strategies and project documents as well as national plans is conducted to assess the degree of attention to climate change concerns in development planning and assistance. Third, an in-depth analysis is conducted for adaptation in coastal zones as well as for mainstreaming carbonsequestration within the agriculture and forestry sectors

Constraints on Climate and Habitability for Earth-like Exoplanets Determined from a General Circulation Model

International Nuclear Information System (INIS)

Wolf, Eric T.; Toon, Owen B.; Shields, Aomawa L.; Kopparapu, Ravi K.; Haqq-Misra, Jacob

2017-01-01

Conventional definitions of habitability require abundant liquid surface water to exist continuously over geologic timescales. Water in each of its thermodynamic phases interacts with solar and thermal radiation and is the cause for strong climatic feedbacks. Thus, assessments of the habitable zone require models to include a complete treatment of the hydrological cycle over geologic time. Here, we use the Community Atmosphere Model from the National Center for Atmospheric Research to study the evolution of climate for an Earth-like planet at constant CO 2 , under a wide range of stellar fluxes from F-, G-, and K-dwarf main sequence stars. Around each star we find four stable climate states defined by mutually exclusive global mean surface temperatures ( T s ); snowball ( T s ≤ 235 K), waterbelt (235 K ≤ T s ≤ 250 K), temperate (275 K ≤ T s ≤ 315 K), and moist greenhouse ( T s ≥ 330 K). Each is separated by abrupt climatic transitions. Waterbelt, temperate, and cooler moist greenhouse climates can maintain open-ocean against both sea ice albedo and hydrogen escape processes respectively, and thus constitute habitable worlds. We consider the warmest possible habitable planet as having T s ∼ 355 K, at which point diffusion limited water-loss could remove an Earth ocean in ∼1 Gyr. Without long timescale regulation of non-condensable greenhouse species at Earth-like temperatures and pressures, such as CO 2 , habitability can be maintained for an upper limit of ∼2.2, ∼2.4, and ∼4.7 Gyr around F-, G-, and K-dwarf stars respectively, due to main sequence brightening.

Constraints on Climate and Habitability for Earth-like Exoplanets Determined from a General Circulation Model

Energy Technology Data Exchange (ETDEWEB)

Wolf, Eric T.; Toon, Owen B. [Laboratory for Atmospheric and Space Physics, Department of Atmospheric and Oceanic Sciences, University of Colorado, Boulder, CO (United States); Shields, Aomawa L. [University of California, Irvine, Department of Physics and Astronomy, 4129 Frederick Reines Hall, Irvine, CA 92697 (United States); Kopparapu, Ravi K.; Haqq-Misra, Jacob, E-mail: eric.wolf@colorado.edu [NASA Astrobiology Institute' s Virtual Planetary Laboratory, P.O. Box 351580, Seattle, WA 98195 (United States)

2017-03-10

Conventional definitions of habitability require abundant liquid surface water to exist continuously over geologic timescales. Water in each of its thermodynamic phases interacts with solar and thermal radiation and is the cause for strong climatic feedbacks. Thus, assessments of the habitable zone require models to include a complete treatment of the hydrological cycle over geologic time. Here, we use the Community Atmosphere Model from the National Center for Atmospheric Research to study the evolution of climate for an Earth-like planet at constant CO{sub 2}, under a wide range of stellar fluxes from F-, G-, and K-dwarf main sequence stars. Around each star we find four stable climate states defined by mutually exclusive global mean surface temperatures ( T {sub s}); snowball ( T {sub s} ≤ 235 K), waterbelt (235 K ≤ T {sub s} ≤ 250 K), temperate (275 K ≤ T {sub s} ≤ 315 K), and moist greenhouse ( T {sub s} ≥ 330 K). Each is separated by abrupt climatic transitions. Waterbelt, temperate, and cooler moist greenhouse climates can maintain open-ocean against both sea ice albedo and hydrogen escape processes respectively, and thus constitute habitable worlds. We consider the warmest possible habitable planet as having T {sub s} ∼ 355 K, at which point diffusion limited water-loss could remove an Earth ocean in ∼1 Gyr. Without long timescale regulation of non-condensable greenhouse species at Earth-like temperatures and pressures, such as CO{sub 2}, habitability can be maintained for an upper limit of ∼2.2, ∼2.4, and ∼4.7 Gyr around F-, G-, and K-dwarf stars respectively, due to main sequence brightening.

Field observations of climbing behavior and seed predation by adult ground beetles (Coleoptera: Carabidae) in a lowland area of the temperate zone.

Science.gov (United States)

Sasakawa, Kôji

2010-10-01

Granivory is a specialized food habit in the predominantly carnivorous beetle family Carabidae. Most studies of carabid granivory have been conducted under laboratory conditions; thus, our knowledge of the feeding ecology of granivorous carabids in the field is insufficient. I conducted field observations of climbing behavior and seed predation by adult carabids in a lowland area of eastern Japan, from early October to late November in 2008. This is the first systematic field observation of the feeding ecology of granivorous carabids in the temperate zone. In total, 176 carabid individuals of 11 species were observed, with 108 individuals feeding on plant seeds/flowers. Each carabid species was primarily observed feeding on a particular plant species. Frequently observed combinations were: Amara gigantea Motschulsky on Humulus scandens (Loureiro) Merrill (Moraceae) seed, Amara lucens Baliani on Artemisia indica Willdenow (Asteraceae) flower, and Amara macronota (Solsky) and Harpalus (Pseudoophonus) spp. on Digitaria ciliaris (Retzius) Koeler (Poaceae) seed. In all but one species, the sex ratio of individuals observed feeding was female-biased. In Am. gigantea and Am. macronota, a larger proportion of females than males ate seeds. In the three Amara species, copulations on plants, with the female feeding on its seeds/flowers, were often observed. These observations may indicate that, whereas females climb onto plants to feed on seeds, males climb to seek females for copulation rather than forage. Because granivorous carabids play important roles as weed-control agents in temperate agro-ecosystems, the present results would provide valuable basic information for future studies on this subject.

World temperate fruit production: characteristics and challenges

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Jorge B. Retamales

2011-10-01

Full Text Available In the last 30 years world population has increased 70% but per capita global fruit consumption is only 20% higher. Even though tropical and temperate fruit have similar contributions to the 50 kg/person/year of US consumption of fresh fruit, in the last 30 years this has been slightly greater for temperate fruit. Within fruit consumption, the largest expansion has been for organic fruit which increased more than 50% in the 2002-2006 period. The largest expansion of area planted in the 1996-2006 has been for kiwi (29% and blueberries (20%, while apples (-24% and sour cherries (-13% have had the largest reductions. Nearly 50% of the total global volume of fruit is produced by 5 countries: China, USA, Brazil, Italy and Spain. The main producer (China accounts for 23% of the total. While the main exporters are Spain, USA and Italy, the main importers are Germany, Russia and UK. Demands for the industry have evolved towards quality, food safety and traceability. The industry faces higher productions costs (labor, energy, agrichemicals. The retailers are moving towards consolidation while the customers are changing preferences (food for health. In this context there is greater pressure on growers, processors and retailers. Emerging issues are labor supply, climate change, water availability and sustainability. Recent developments in precision agriculture, molecular biology, phenomics, crop modelling and post harvest physiology should increase yields and quality, and reduce costs for temperate fruit production around the world.

Time-temperature equivalence in Martensite tempering

Energy Technology Data Exchange (ETDEWEB)

Hackenberg, Robert E. [Los Alamos National Laboratory; Thomas, Grant A. [CSM; Speer, John G. [CSM; Matlock, David K. [CSM; Krauss, George [CSM

2008-06-16

The relationship between time and temperature is of great consequence in many materials-related processes including the tempering of martensite. In 1945, Hollomon and Jaffe quantified the 'degree of tempering' as a function of both tempering time, t, and tempering temperature, T, using the expression, T(log t + c). Here, c is thought to be a material constant and appears to decrease linearly with increasing carbon content. The Hollomon-Jaffe tempering parameter is frequently cited in the literature. This work reviews the original derivation of the tempering parameter concept, and presents the use of the characteristics diffusion distance as an alternative time-temperature relationship during martensite tempering. During the tempering of martensite, interstitial carbon atoms diffuse to form carbides. In addition, austenite decomposes, dislocations and grain boundaries rearrange, associated with iron self diffusion. Since these are all diffusional processes, it is reasonable to expect the degree of tempering to relate to the extent of diffusion.

A common framework for greenhouse gas assessment protocols in temperate agroforestry systems: Connecting via GRACEnet

Science.gov (United States)

Agroforestry systems offer many ecosystem benefits, but such systems have previously been marginalized in temperate environments due to overriding economic goals and perceived management complexity. In view of adaptation to a changing climate, agroforestry systems offer advantages that require quan...

Appropriate welding conditions of temper bead weld repair for SQV2A pressure vessel steel

International Nuclear Information System (INIS)

Mizuno, R.; Matsuda, F.; Brziak, P.; Lomozik, M.

2004-01-01

Temper bead welding technique is one of the most important repair welding methods for large structures for which it is difficult to perform the specified post weld heat treatment. In this study, appropriate temper bead welding conditions to improve the characteristics of heat affected zone (HAZ) are studied using pressure vessel steel SQV2A corresponding to ASTM A533 Type B Class 1. Thermal/mechanical simulator is employed to give specimens welding thermal cycles from single to quadruple cycle. Charpy absorbed energy and hardness of simulated CGHAZ by first cycle were degraded as compared with base metal. Improvability of these degradations by subsequent cycles is discussed and appropriate temper bead thermal cycles are clarified. When the peak temperature lower than Ac1 and near Ac1 in the second thermal cycle is applied to CGAHZ by first thermal cycle, the characteristics of CGHAZ improve enough. When the other peak temperatures (that is, higher than Ac1) in the second thermal cycle are applied to the CGHAZ, third or more thermal cycle temper bead process should be applied to improve the properties. Appropriate weld condition ranges are selected based on the above results. The validity of the selected ranges is verified by the temper bead welding test. (orig.)

Evaluation of factors affecting soil carbon sequestration services of stormwater wet retention ponds in varying climate zones.

Science.gov (United States)

Merriman, L S; Moore, T L C; Wang, J W; Osmond, D L; Al-Rubaei, A M; Smolek, A P; Blecken, G T; Viklander, M; Hunt, W F

2017-04-01

The carbon sequestration services of stormwater wet retention ponds were investigated in four different climates: U.S., Northern Sweden, Southern Sweden, and Singapore, representing a range of annual mean temperatures, growing season lengths and rainfall depths: geographic factors that were not statistically compared, but have great effect on carbon (C) accumulation. A chronosequence was used to estimate C accumulations rates; C accumulation and decomposition rates were not directly measured. C accumulated significantly over time in vegetated shallow water areas (0-30cm) in the USA (78.4gCm -2 yr -1 ), in vegetated temporary inundation zones in Sweden (75.8gCm -2 yr -1 ), and in all ponds in Singapore (135gCm -2 yr -1 ). Vegetative production appeared to exert a stronger influence on relative C accumulation rates than decomposition. Comparing among the four climatic zones, the effects of increasing rainfall and growing season lengths (vegetative production) outweighed the effects of higher temperature on decomposition rates. Littoral vegetation was a significant source to the soil C pool relative to C sources draining from watersheds. Establishment of vegetation in the shallow water zones of retention ponds is vital to providing a C source to the soil. Thus, the width of littoral shelves containing this vegetation along the perimeter may be increased if C sequestration is a design goal. This assessment establishes that stormwater wet retention ponds can sequester C across different climate zones with generally annual rainfall and lengths of growing season being important general factors for C accumulation. Copyright © 2017 Elsevier B.V. All rights reserved.

Interspecific variation in total phenolic content in temperate brown algae

Directory of Open Access Journals (Sweden)

Anna Maria Mannino

2017-09-01

Full Text Available Marine algae synthesize secondary metabolites such as polyphenols that function as defense and protection mechanisms. Among brown algae, Fucales and Dictyotales (Phaeophyceae contain the highest levels of phenolic compounds, mainly phlorotannins, that play multiple roles. Four temperate brown algae (Cystoseira amentacea, Cystoseira compressa, Dictyopteris polypodioides and Padina pavonica were studied for total phenolic contents. Total phenolic content was determined colorimetrically with the Folin-Ciocalteu reagent. Significant differences in total phenolic content were observed between leathery and sheetlike algae and also within each morphological group. Among the four species, the sheet-like alga D. polypodioides, living in the upper infralittoral zone, showed the highest concentration of phenolic compounds. These results are in agreement with the hypothesis that total phenolic content in temperate brown algae is influenced by a combination of several factors, such as growth form, depth, and exposition to solar radiation.

Holocene climate variability and oceanographic changes off western South Africa

Science.gov (United States)

Zhao, Xueqin; Dupont, Lydie; E Meadows, Michael; Schefuß, Enno; Bouimetarhan, Ilham; Wefer, Gerold

2017-04-01

South Africa is located at a critical transition zone between subtropical and warm-temperate climate zones influenced by the Indian and Atlantic oceans. Presently, the seasonal changes of atmospheric and oceanic systems induce a pronounced rainfall seasonality comprised of two different rainfall zones over South Africa. How did this seasonality develop during the Holocene? To obtain a better understanding of how South African climates have evolved during the Holocene, we conduct a comprehensive spatial-temporal approach including pollen and dinoflagellate cyst records from marine sediment samples retrieved from the Namaqualand mudbelt, a Holocene terrigenous mud deposit on the shelf of western South Africa. The representation of different vegetation communities in western South Africa is assessed through pollen analysis of surface sediments. This approach allows for climate reconstructions of the summer rainfall zone (SRZ) using Group 1 (Poaceae, Cyperaceae, Phragmites-type and Typha) and winter rainfall zone (WRZ) using Group 2 (Restionaceae, Ericaceae, Anthospermum, Stoebe/Elytropappus-type, Cliffortia, Passerina, Artemisia-type and Pentzia-type) from a single marine archive. The fossil pollen data from gravity core GeoB8331-4 indicate contrasting climate patterns in the SRZ and WRZ especially during the early and middle Holocene. The rainfall amount in the SRZ is dominated by insolation forcing, while in the WRZ it is mainly attributed to the latitudinal position of the southern westerlies. Dinoflagellate cyst data show significantly different oceanographic conditions associated with climate changes on land. High percentages of autotrophic taxa like Operculodinium centrocarpum and Spiniferites spp. indicate warm and stratified conditions during the early Holocene, suggesting reduced upwelling. In contrast, the middle Holocene is characterized by a strong increase in heterotrophic taxa in particular Lejeunecysta paratenella and Echinidinium spp., indicating cool

Altitudinal variation in soil organic carbon stock in coniferous subtropical and broadleaf temperate forests in Garhwal Himalaya

Directory of Open Access Journals (Sweden)

Kumar Munesh

2009-08-01

Full Text Available Abstract Background The Himalayan zones, with dense forest vegetation, cover a fifth part of India and store a third part of the country reserves of soil organic carbon (SOC. However, the details of altitudinal distribution of these carbon stocks, which are vulnerable to forest management and climate change impacts, are not well known. Results This article reports the results of measuring the stocks of SOC along altitudinal gradients. The study was carried out in the coniferous subtropical and broadleaf temperate forests of Garhwal Himalaya. The stocks of SOC were found to be decreasing with altitude: from 185.6 to 160.8 t C ha-1 and from 141.6 to 124.8 t C ha-1 in temperature (Quercus leucotrichophora and subtropical (Pinus roxburghii forests, respectively. Conclusion The results of this study lead to conclusion that the ability of soil to stabilize soil organic matter depends negatively on altitude and call for comprehensive theoretical explanation

Evapotranspiration and soil moisture dynamics in a temperate grassland ecosystem in Inner Mongolia China

Science.gov (United States)

L. Hao; Ge Sun; Yongqiang Liu; G. S. Zhou; J. H.   Wan;  L. B. Zhang; J. L. Niu; Y. H. Sang;  J. J He

2015-01-01

Precipitation, evapotranspiration (ET), and soil moisture are the key controls for the productivity and functioning of temperate grassland ecosystems in Inner Mongolia, northern China. Quantifying the soil moisture dynamics and water balances in the grasslands is essential to sustainable grassland management under global climate change. We...

Climate variability and environmental stress in the Sudan-Sahel zone of West Africa.

Science.gov (United States)

Mertz, Ole; D'haen, Sarah; Maiga, Abdou; Moussa, Ibrahim Bouzou; Barbier, Bruno; Diouf, Awa; Diallo, Drissa; Da, Evariste Dapola; Dabi, Daniel

2012-06-01

Environmental change in the Sudan-Sahel region of West Africa (SSWA) has been much debated since the droughts of the 1970s. In this article we assess climate variability and environmental stress in the region. Households in Senegal, Mali, Burkina Faso, Niger, and Nigeria were asked about climatic changes and their perceptions were compared across north-south and west-east rainfall gradients. More than 80% of all households found that rainfall had decreased, especially in the wettest areas. Increases in wind speeds and temperature were perceived by an overall 60-80% of households. Contrary to household perceptions, observed rainfall patterns showed an increasing trend over the past 20 years. However, August rainfall declined, and could therefore potentially explain the contrasting negative household perceptions of rainfall trends. Most households reported degradation of soils, water resources, vegetation, and fauna, but more so in the 500-900 mm zones. Adaptation measures to counter environmental degradation included use of manure, reforestation, soil and water conservation, and protection of fauna and vegetation. The results raise concerns for future environmental management in the region, especially in the 500-900 mm zones and the western part of SSWA.

Crop residue management in arable cropping systems under a temperate climate. Part 2: Soil physical properties and crop production. A review

Directory of Open Access Journals (Sweden)

Hiel, MP.

2016-01-01

Full Text Available Introduction. Residues of previous crops provide a valuable amount of organic matter that can be used either to restore soil fertility or for external use. A better understanding of the impact of crop residue management on the soil-water-plant system is needed in order to manage agricultural land sustainably. This review focuses on soil physical aspects related to crop residue management, and specifically on the link between soil structure and hydraulic properties and its impact on crop production. Literature. Conservation practices, including crop residue retention and non-conventional tillage, can enhance soil health by improving aggregate stability. In this case, water infiltration is facilitated, resulting in an increase in plant water availability. Conservation practices, however, do not systematically lead to higher water availability for the plant. The influence of crop residue management on crop production is still unclear; in some cases, crop production is enhanced by residue retention, but in others crop residues can reduce crop yield. Conclusions. In this review we discuss the diverse and contrasting effects of crop residue management on soil physical properties and crop production under a temperate climate. The review highlights the importance of environmental factors such as soil type and local climatic conditions, highlighting the need to perform field studies on crop residue management and relate them to specific pedo-climatic contexts.

Factors influencing smallholder farmers' behavioural intention towards adaptation to climate change in transitional climatic zones: A case study of Hwedza District in Zimbabwe.

Science.gov (United States)

Zamasiya, Byron; Nyikahadzoi, Kefasi; Mukamuri, Billy Billiard

2017-08-01

This paper examines factors influencing behavioural change among smallholder farmers towards adaptation to climate change in transitional climatic zones of Africa, specifically, Hwedza District in Zimbabwe. Data for this study were collected from 400 randomly-selected smallholder farmers, using a structured questionnaire, focus group discussions and key informant interviews. The study used an ordered logit model to examine the factors that influence smallholder farmers' behavioural intention towards adaptation to climate change. Results from the study show that the gender of the household head, access to extension services on crop and livestock production, access to climate information, membership to social groups and experiencing a drought have a positive influence on farmers' attitude towards adaptation to climate change and variability. The study concluded that although the majority of smallholder farmers perceive that the climate is changing, they continue to habour negative attitudes towards prescribed climate change adaptation techniques. This study recommends more education on climate change, as well as adaptation strategies for both agricultural extension workers and farmers. This can be complemented by disseminating timely climate information through extension officers and farmers' groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ecosystem-level changes that may be expected in a changing global climate - a British Columbia perspective. [Canada - British Columbia

Energy Technology Data Exchange (ETDEWEB)

Kimmins, J.P.; Lavender, D.P. (Univ. of British Columbia, Vancouver, BC (Canada). Dept. of Forest Science)

1992-08-01

British Columbia is a vast province encompassing a wide latitudinal and elevational range. Four of the five major classes of climate in the world are found in British Columbia, where prevailing westerly winds from the Pacific and a series of north-south mountain ranges have produced widely differing local climates. The predicted global warming may result in the migration of species and communities upslope and toward the north, but the heterogenous nature of the present landscape suggests that such migration may not be as pronounced as that likely to occur in regions of Canada with less relief. Effects of climatic warming on long-lived temperate zone trees include possible increased frost damage in early spring; reduced seed production; increased insect and disease incidence; increased damage to forests by wildfire; and, in the warmer parts of coastal British Columbia, a winter climate too warm to satisfy the chilling requirements of some perennial plants.

RURAL FARMERS’ PERCEPTION OF CLIMATE CHANGE IN CENTRAL AGRICULTURAL ZONE OF DELTA STATE, NIGERIA

Directory of Open Access Journals (Sweden)

A.U. Ofuoku

2011-10-01

Full Text Available Farmer perception of their environment is a factor of climate change. Adaptation to climate change requires farmers to realize that the climate has changed and they must identify useful adaptations and implement them. This study analyzed the per-ception of climate change among rural farmers in central agri-cultural zone of Delta State, Nigeria. Climate change studies often assume certain adaptations and minimal examination of how, when, why, and conditions under which adaptations usually take place in any economic and social systems. The study was conducted by survey method on 131 respondents using struc-tured interview schedule and questionnaire. Data were analyzed with descriptive statistics and linear regression model to test that education, gender, and farming experience influenced farmers’ perception of climate change. The results showed that the farmers were aware of climate change. The identified causes of climate change were ranging from intensified agriculture, population explosion, increased use of fossil fuel, loss of in-digenous know practice to gas flaring. The effects of climate change on crops and livestocks were also identified by the rural farmers. Many of the farmers adapted to climate change by planting trees, carrying out soil conservation practice, changing planting dates, using different crop varieties, installing fans in livestock pens, and applying irrigation. Almost half of them did not adapt to climate change. The linear regression analysis revealed that education, gender, and farming experience influ-enced farmers’ perception of climate change. The major barriers to adaptation to climate change included lack of information, lack of money, and inadequate land.

Coastal Wetland Ecosystem Responses to Climate Change: the Role of Macroclimatic Drivers along the Northern Gulf of Mexico

Science.gov (United States)

Osland, M. J.; Enwright, N.; Day, R. H.; Gabler, C. A.; Stagg, C. L.; From, A. S.

2014-12-01

Across the globe, macroclimatic drivers greatly influence coastal wetland ecosystem structure and function. However, changing macroclimatic conditions are rarely incorporated into coastal wetland vulnerability assessments. Here, we quantify the influence of macroclimatic drivers upon coastal wetland ecosystems along the Northern Gulf of Mexico (NGOM) coast. From a global perspective, the NGOM coast provides several excellent opportunities to examine the effects of climate change upon coastal wetlands. The abundant coastal wetland ecosystems in the region span two major climatic gradients: (1) a winter temperature gradient that crosses temperate to tropical climatic zones; and (2) a precipitation gradient that crosses humid to semi-arid zones. We present analyses where we used geospatial data (historical climate, hydrology, and coastal wetland coverage) and field data (soil, elevation, and plant community composition and structure) to quantify climate-mediated ecological transitions. We identified winter climate and precipitation-based thresholds that separate mangrove forests from salt marshes and vegetated wetlands from unvegetated wetlands, respectively. We used simple distribution and abundance models to evaluate the potential ecological effects of alternative future climate change scenarios. Our results illustrate and quantify the importance of macroclimatic drivers and indicate that climate change could result in landscape-scale changes in coastal wetland ecosystem structure and function. These macroclimate-mediated ecological changes could affect the supply of some ecosystem goods and services as well as the resilience of these ecosystems to stressors, including accelerated sea level rise. Collectively, our findings highlight the importance of incorporating macroclimatic drivers within future-focused coastal wetland vulnerability assessments.

The Species Richness of Vascular Plants and Amphibia in Major Plant Communities in Temperate to Tropical Australia: Relationship with Annual Biomass Production

International Nuclear Information System (INIS)

Specht, R. L.; Tyler, M.J.

2010-01-01

Aerodynamic fluxes (frictional, thermal, evaporative) in the atmosphere as it flows over and through a plant community determine the Foliage Projective Covers and eco-morphological attributes of new leaves developed annually in overstorey and understorey strata. The number of leaves produced on vertical foliage shoots depends on available soil water and nutrients, also ambient temperature, during this short growth season. Stem density (number of stems per hectare) and species richness (number of species per hectare) in the overstorey of major Floristic Groups are correlated with annual shoot growth (ASG, t ha-1) in that stratum. Species richness in the overstorey increases in the climatic gradient from the arid to the humid zone as well as with increasing air temperatures (about 10 degree C) from temperate to tropical Australia. Species richness in the understorey is highest in plant communities in temperate Australia, decreasing in the temperature gradient towards the tropics. As with other major plant and animal groups within an ecosystem, the species richness of Amphibia is correlated with the amount of solar energy fixed (per annum) by the major plant formation in the regional photosynthetic potential determined by the foliage shoots (ASG, t ha-1) produced annually in the overstorey.

The Species Richness of Vascular Plants and Amphibia in Major Plant Communities in Temperate to Tropical Australia: Relationship with Annual Biomass Production

Directory of Open Access Journals (Sweden)

R. L. Specht

2010-01-01

Full Text Available Aerodynamic fluxes (frictional, thermal, evaporative in the atmosphere as it flows over and through a plant community determine the Foliage Projective Covers and eco-morphological attributes of new leaves developed annually in overstorey and understorey strata. The number of leaves produced on vertical foliage shoots depends on available soil water and nutrients, also ambient temperature, during this short growth season. Stem density (number of stems per hectare and species richness (number of species per hectare in the overstorey of major Floristic Groups are correlated with annual shoot growth (ASG, t ha−1 in that stratum. Species richness in the overstorey increases in the climatic gradient from the arid to the humid zone as well as with increasing air temperatures (about 10oC from temperate to tropical Australia. Species richness in the understorey is highest in plant communities in temperate Australia, decreasing in the temperature gradient towards the tropics. As with other major plant and animal groups within an ecosystem, the species richness of Amphibia is correlated with the amount of solar energy fixed (per annum by the major plant formation in the region—a photosynthetic potential determined by the foliage shoots (ASG, t ha−1 produced annually in the overstorey.

IDENTIFYING LOCAL SCALE CLIMATE ZONES OF URBAN HEAT ISLAND FROM HJ-1B SATELLITE DATA USING SELF-ORGANIZING MAPS

Directory of Open Access Journals (Sweden)

C. Z. Wei

2016-10-01

Full Text Available With the increasing acceleration of urbanization, the degeneration of the environment and the Urban Heat Island (UHI has attracted more and more attention. Quantitative delineation of UHI has become crucial for a better understanding of the interregional interaction between urbanization processes and the urban environment system. First of all, our study used medium resolution Chinese satellite data-HJ-1B as the Earth Observation data source to derive parameters, including the percentage of Impervious Surface Areas, Land Surface Temperature, Land Surface Albedo, Normalized Differential Vegetation Index, and object edge detector indicators (Mean of Inner Border, Mean of Outer border in the city of Guangzhou, China. Secondly, in order to establish a model to delineate the local climate zones of UHI, we used the Principal Component Analysis to explore the correlations between all these parameters, and estimate their contributions to the principal components of UHI zones. Finally, depending on the results of the PCA, we chose the most suitable parameters to classify the urban climate zones based on a Self-Organization Map (SOM. The results show that all six parameters are closely correlated with each other and have a high percentage of cumulative (95% in the first two principal components. Therefore, the SOM algorithm automatically categorized the city of Guangzhou into five classes of UHI zones using these six spectral, structural and climate parameters as inputs. UHI zones have distinguishable physical characteristics, and could potentially help to provide the basis and decision support for further sustainable urban planning.

Vascular plant species richness along environmental gradients in a cool temperate to sub-alpine mountainous zone in central Japan.

Science.gov (United States)

Tsujino, Riyou; Yumoto, Takakazu

2013-03-01

In order to clarify how vegetation types change along the environmental gradients in a cool temperate to sub-alpine mountainous zone and the determinant factors that define plant species richness, we established 360 plots (each 4 × 10 m) within which the vegetation type, species richness, elevation, topographic position index (TPI), slope inclination, and ground light index (GLI) of the natural vegetation were surveyed. Mean elevation, TPI, slope inclination, and GLI differed across vegetation types. Tree species richness was negatively correlated with elevation, whereas fern and herb species richness were positively correlated. Tree species richness was greater in the upper slope area than the lower slope area, whereas fern and herb species richness were greater in the lower slope area. Ferns and trees species richness were smaller in the open canopy, whereas herb species richness was greater in the open canopy. Vegetation types were determined firstly by elevation and secondary by topographic configurations, such as topographic position, and slope inclination. Elevation and topography were the most important factors affecting plant richness, but the most influential variables differed among plant life-form groups. Moreover, the species richness responses to these environmental gradients greatly differed among ferns, herbs, and trees.

Analysis of Solar Chimneys in Different Climate Zones - Case of Social Housing in Ecuador

Science.gov (United States)

Godoy-Vaca, Luis; Almaguer, Manuel; Martínez-Gómez, Javier; Lobato, Andrea; Palme, Massimo

2017-10-01

The aim of this research is to simulate the performance of a solar chimney located in different macro-zones in Ecuador. The proposed solar chimney model was simulated using a python script in order to predict the temperature distribution and the mass flow over time. The results obtained were firstly compared with experimental data for dry-warm climate. Then, the model was evaluated and tested in real weather conditions: dry-warm, moist-warm and rainy-cold. In addition, the assumed chimney dimensions were chosen according to the literature for the studied conditions. In spite of evaluating the best nightly ventilation, different chimney wall materials were tested: solid brick, common brick and reinforced concrete. The results showed that concrete in a dry-warm climate, a metallic layer on the gap with solid brick in a moist-warm climate and reinforced concrete in a rainy cold climate used for the absorbent wall improve the thermal inertia of the social housing.

Climate Change and Coastal Zones. An Overview of the State-of-the-Art on Regional and Local Vulnerability Assessment

International Nuclear Information System (INIS)

Sterr, H.; Klein, R.J.T.; Reese, S.

2000-06-01

This paper provides an overview of the latest developments in methodologies for assessing the vulnerability of coastal zones to climate change at regional and local scales. The focus of vulnerability assessment in coastal zones used to be on erosion and land loss due to sea-level rise. Methodologies now increasingly consider the wide range of climate and impact variables that play a part in determining coastal vulnerability, as well as non-climatic developments. The paper presents a conceptual framework for vulnerability assessment that identifies a number of system components that can be considered determinants of vulnerability. It then goes on to outline a number of steps that are required for the actual assessment of coastal vulnerability, such as scenario development, data collection and impact assessment. The approach is illustrated using a regional and local case study in Germany

Improving modelled impacts on the flowering of temperate fruit trees in the Iberian Peninsula of climate change projections for 21st century

Science.gov (United States)

Ruiz-Ramos, Margarita; Pérez-Lopez, David; Sánchez-Sánchez, Enrique; Centeno, Ana; Dosio, Alessandro; Lopez-de-la-Franca, Noelia

2013-04-01

Flowering of temperate trees needs winter chilling, being the specific requirements dependent on the variety. This work studied the trend and changes of values of chilling hours for some representative agricultural locations in Spain for the last three decades and their projected changes under climate change scenarios. According to our previous results (Pérez-López et al., 2012), areas traditionally producing fruit as the Ebro (NE of Spain) or Guadalquivir (SO) valleys, Murcia (SE) and Extremadura (SO) could have a major cold reduction of chill-hours. This would drive a change of varieties or species and may enhance the use of chemicals to complete the needs of chill hours for flowering. However, these results showed high uncertainty, partly due to the bias of the climate data used, generated by Regional Climate Models. The chilling hours were calculated with different methods according to the species considered: North Carolina method (Shaltout and Unrath, 1983) was used for apples, Utah method (Richardson et al. 1974) for peach and grapevine and the approach used by De Melo-Abreu et al. (2004) for olive trees. The climate data used as inputs were the results of numerical simulations obtained from a group of regional climate models at high resolution (25 km) from the European Project ENSEMBLES (http://www.ensembles-eu.org/) first bias corrected for temperatures and precipitation (Dosio and Paruolo, 2011; Dosio et al., 2012). This work aims to improve the impact projections obtained in Pérez-López et al. (2012). For this purpose, variation of chill-hours between 2nd half of 20th century and 1st half of 21st century at the study locations were recalculated considering 1) a feedback in the dates in which the chilling hours are calculated, to take into account the shift of phenological dates, and 2) substituting the original ENSEMBLES data set of climate used in Pérez-López et al. (2012) by the bias corrected data set. Calculations for the 2nd half of 20th

Migration of heavy natural radionuclides in a humid climatic zone

International Nuclear Information System (INIS)

Titaeva, N.A.; Alexakhin, R.M.; Taskaev, A.I.; Maslov, V.I.

1980-01-01

Regularities and biochemical peculiarities of the migrations of heavy natural radionuclides in the environment are examined, with special reference to two regions in a humid climatic zone representing natural patterns of radionuclide distribution and to four plots artificially contaminated with high levels of natural radioactivity more than 20 years previously. It was determined that the migration of thorium, uranium, and radium isotopes through the rock-water-soil-plant system is dependent on many physiochemical properties of these radionuclides, their compounds, and the local environment. Isotopic activity ratios provide a useful tool for studying the direction of radionuclide migration and its influence on observed distribution patterns

Potential evapotranspiration trend analysis for different climatic zones in Khyber Pakhtunkhwa, Pakistan

International Nuclear Information System (INIS)

Nazeer, M.

2012-01-01

Estimation of potential evapotranspiration (ETo) plays a significant role in the study of water resources management. The study was conducted to investigate the change in potential evapotranspiration value during the past three decade in three diverse climatic zones of Khyber Pakhtunkhwa, Pakistan. Three Districts of Khyber Pakhtunkhwa, Pakistan (Chitral, Peshawar and D. I. Khan) were selected based on their climatic diversity. Thirty years climatic data (1981-2010) obtained from Pakistan Metrological Department, Islamabad and Agriculture Research Institute, Peshawar was used. Potential evapotranspiration was determined for three decades separately, as well as on mean monthly basis. World Meteorological Organization (WMO) technique was used for trend analysis. Results revealed highest ETo in D. I. Khan followed by Peshawar and Chitral. However, in the summer months ETo value was found highest in Chitral as compared to other selected Districts. Trend analysis results showed that decrease in ETo trend was observed in all the selected Districts with the passage of time. It can be concluded that ETo values decreased as compared to past in all the selected Districts without any discrimination of physical geography and location. (author)

Climate change, cranes, and temperate floodplain ecosystems

Science.gov (United States)

King, Sammy L.

2010-01-01

Floodplain ecosystems provide important habitat to cranes globally. Lateral, longitudinal, vertical, and temporal hydrologic connectivity in rivers is essential to maintaining the functions and values of these systems. Agricultural development, flood control, water diversions, dams, and other anthropogenic activities have greatly affected hydrologic connectivity of river systems worldwide and altered the functional capacity of these systems. Although the specific effects of climate change in any given area are unknown, increased intensity and frequency of flooding and droughts and increased air and water temperatures are among many potential effects that can act synergistically with existing human modifications in these systems to create even greater challenges in maintaining ecosystem productivity. In this paper, I review basic hydrologic and geomorphic processes of river systems and use three North American rivers (Guadalupe, Platte, and Rio Grande) that are important to cranes as case studies to illustrate the challenges facing managers tasked with balancing the needs of cranes and people in the face of an uncertain climatic future. Each river system has unique natural and anthropogenic characteristics that will affect conservation strategies. Mitigating the effects of climate change on river systems necessitates an understanding of river/floodplain/landscape linkages, which include people and their laws as well as existing floodplain ecosystem conditions.

Optimal control and performance of photovoltachromic switchable glazing for building integration in temperate climates

International Nuclear Information System (INIS)

Favoino, Fabio; Fiorito, Francesco; Cannavale, Alessandro; Ranzi, Gianluca; Overend, Mauro

2016-01-01

Highlights: • The features and properties of photovoltachromic switchable glazing are presented. • The different possible control strategies for the switchable glazing are presented. • Thermal and daylight performance are co-simulated for rule-based and optimal control. • A novel building performance simulation framework is developed for this aim. • Switchable glazing performance is compared for different controls and climates. - Abstract: The development of adaptive building envelope technologies, and particularly of switchable glazing, can make significant contributions to decarbonisation targets. It is therefore essential to quantify their effect on building energy use and indoor environmental quality when integrated into buildings. The evaluation of their performance presents new challenges when compared to conventional “static” building envelope systems, as they require design and control aspects to be evaluated together, which are also mutually interrelated across thermal and visual physical domains. This paper addresses these challenges by presenting a novel simulation framework for the performance evaluation of responsive building envelope technologies and, particularly, of switchable glazing. This is achieved by integrating a building energy simulation tool and a lighting simulation one, in a control optimisation framework to simulate advanced control of adaptive building envelopes. The performance of a photovoltachromic glazing is evaluated according to building energy use, Useful Daylight Illuminance, glare risk and load profile matching indicators for a sun oriented office building in different temperate climates. The original architecture of photovoltachromic cell provides an automatic control of its transparency as a function of incoming solar irradiance. However, to fully explore the building integration potential of photovoltachromic technology, different control strategies are evaluated, from passive and simple rule based controls, to

Evaluating climate variability and management impacts on carbon dynamics of a temperate forest using a variety of techniques

Science.gov (United States)

Arain, M. A.

2015-12-01

Climate variability, extreme weather events, forest age and management history impacts carbon sequestration in forest ecosystems. A variety of measurement techniques such as eddy covariance, dendrochronology, automatic soil CO2 chambers and remote sensing are employed fully understand forest carbon dynamics. Here, we present carbon flux measurements from 2003-2014 in a 76-year old managed temperate pine ((-Pinus strobus L.) forest, near Lake Erie in southern Ontario, Canada. Forest was partially thinned (30% tree harvested) in 1983 and 2012. The thinning in 2012 did not significantly impact carbon fluxes as post-thinning fluxes were within the range of inter-annual variability. Mean annual post-thinning (2012-2104) gross ecosystem productivity (GEP) measure by the eddy covariance technique was 1518 ± 78 g C m-2 year-1 as compared to pre-thinning (2003-2011) GEP of 1384 ± 121 g C m-2·year-1. Over the same period, mean post-thinning net ecosystem productivity (NEP) was 185 ± 75 g C m-2 year-1 as compared to post-thinning NEP of 180 ± 70 g C m-2 year-1, indicating that pre-thinning NEP was not significantly different than post-thinning NEP. Only post-thinning mean annual ecosystem respiration (Re; 1322 ± 54 g C m-2 year-1) was higher than pre-thinning Re (1195 ± 101 g C m-2 year-1). Soil CO2 efflux measurements showed similar trends. We also evaluated the impacts of climate variability and management regime on the full life cycle of the forest using annual radial tree-ring growths from 15 trees and compared them with historical climate (temperature and precipitation) data. While the annual growth rates displayed weak correlation with long-term climatic records, the growth was generally reduced during years with extreme drought (-36% of mean annual precipitation) and extreme temperature variability (±0.6 - 1.0°C). Overall, forest was more sensitive to management regime than climate variability. It showed higher growth stress during low light condition after

Comparisons of invasive plants in southern Africa originating from southern temperate, northern temperate and tropical regions

Directory of Open Access Journals (Sweden)

L. Henderson

2006-08-01

Full Text Available A subset of invasive alien plant species in southern Africa was analysed in terms of their history of introduction, rate of spread, countries/region of origin, taxonomy, growth forms, cultivated uses, weed status and current distribution in southern Africa, and comparisons made of those originating from south of the tropic of Capricorn, north of the tropic of Cancer and from the tropics. The subset of 233 species, belonging to 58 families, includes all important declared species and some potentially important species. Almost as many species originate from temperate regions (112 as from the tropics (121. Most southern temperate species came from Australia (28/36, most tropical species from tropical America (92/121 and most northern temperate species from Europe (including the Mediterranean and Asia (58/76. Transformers account for 33% of  all species. More transformers are of tropical origin (36 than of northern temperate (24 and southern temperate origin (18. However. 50% of southern temperate species are transformers, compared to 32% of northern temperate and 29% of tropical species. Southern temperate transformer species are mainly woody trees and shrubs that were established on a grand scale as silvicultural crops, barriers (hedges, windbreaks and screens and cover/binders. Most aquatics, herbs, climbers and succulent shrubs an. trom the tropics. Ornamentals are the single largest category of plants from all three regions, the tropics having contributed twice as many species as temperate regions.

Fueling incubation : Differential use of body stores in Arctic and temperate-breeding Barnacle Geese (Branta leucopsis)

NARCIS (Netherlands)

Eichhorn, Goetz; van der Jeugd, Henk P.; Meijer, Harro A. J.; Drent, Rudolf H.

We compared the use of body stores in breeding Barnacle Geese (Branta leucopsis) in traditional Arctic colonies in the Barents Sea with that in recently established temperate-zone breeding colonies in the Baltic Sea and North Sea by studying female body-mass loss and use of fat and protein stores

Effects of climate variability and functional changes on carbon cycling in a temperate deciduous forest

Energy Technology Data Exchange (ETDEWEB)

Wu, Jian

2013-03-15

Temperate forests are globally important carbon (C) stocks and sinks. A decadal (1997-2009) trend of increasing C uptake has been observed in an intensively studied temperate deciduous forest, Soroe (Zealand, Denmark). This gave the impetus to investigate the factors controlling the C cycling and the fundamental processes at work in this type of ecosystem. The major objectives of this study were to (1) evaluate to what extent and at what temporal scales, direct climatic variability and functional changes (e.g. changes in the structure or physiological properties) regulate the interannual variability (IAV) in the ecosystem C balance; (2) provide a synthesis of the ecosystem C budget at this site and (3) investigate whether terrestrial ecosystem models can dynamically simulate the trend of increasing C uptake. Data driven analysis, semi-empirical and process-based modelling experiments were performed in a series of studies in order to provide a complete assessment of the carbon storage and allocation within the ecosystem and clarify the mechanisms responsible for the observed variability and trend in the ecosystem C fluxes. Combining all independently estimated ecosystem carbon budget (ECB) datasets and other calculated ECB components based on mass balance equations, a synthesis of the carbon cycling was performed. The results showed that this temperature deciduous forest was moderately productive with both high rates of gross primary production and ecosystem respiration. Approximately 62% of the gross assimilated carbon was respired by the living plants, while 21% was contributed to the soil as litter production, the latter balancing the total heterotrophic respiration. The remaining 17% was either stored in the plants (mainly as aboveground biomass) or removed from the system as wood production. In general, the ECB component datasets were consistent after the cross-checking. This, together with their characterized uncertainties, can be used in model data fusion

Piping dynamics in mid-altitude mountains under a temperate climate: the Bieszczady Mts., the Eastern Carpathians

Science.gov (United States)

Bernatek-Jakiel, Anita; Jakiel, Michał; Krzemień, Kazimierz

2017-04-01

Soil erosion is caused not only by overland flow, but also by subsurface flow. Piping which is a process of mechanical removal of soil particles by concentrated subsurface flow is frequently being overlooked and not accounted for in soil erosion studies. However, it seems that it is far more widespread than it has often been supposed. Furthermore, our knowledge about piping dynamics and its quantification currently relies on a limited number of data available for mainly loess-mantled areas and marl badlands. Therefore, this research aims to recognize piping dynamics in mid-altitude mountains under a temperate climate, where piping occurs in Cambisols, not previously considered as piping-prone soils. The survey was carried out in the Bereźnica Wyżna catchment (305 ha), in the Bieszczady Mts. (the Eastern Carpathians, Poland), where 188 collapsed pipes were mapped. The research was based on the monitoring of selected piping systems located within grasslands (1971-1974, 2013-2016). The development of piping systems is mainly induced by the elongation of pipes and creation of new collapses (closed depressions and sinkholes), rather than by the enlargement of existing piping forms, or the deepening of pipes. It draws attention to the role of dense vegetation (grasslands) in the delay of pipe collapses and, also, to the boundary of pipe development (soil-bedrock interface). The obtained results reveal an episodic, and even stochastic nature of piping activity, expressed by varied one-year and short-term (3 years) erosion rates, and pipe elongation. Changes in soil loss vary significantly between different years (up to 27.36 t ha-1 y-1), reaching the rate of 1.34 t ha-1 y-1 for the 45-year study period. The elongation of pipes also differs, from no changes to 36 m during one year. The results indicate that soil loss due to piping can cause high soil loss even in highly vegetated lands (grasslands), which are generally considered as areas without a significant erosion

Aridity changes in the temperate-Mediterranean transition of the Andes since ad 1346 reconstructed from tree-rings

Energy Technology Data Exchange (ETDEWEB)

Christie, Duncan A.; Quesne, Carlos le [Universidad Austral de Chile, Laboratorio de Dendrocronologia, Facultad de Ciencias Forestales y Recursos Naturales, Valdivia (Chile); Boninsegna, Jose A.; Morales, Mariano S.; Villalba, Ricardo [Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales, IANIGLA, Departamento de Dendrocronologia e Historia Ambiental, Mendoza (Argentina); Cleaveland, Malcolm K.; Stahle, David W. [University of Arkansas Fayetteville, Tree-Ring Laboratory, Department of Geosciences, Fayetteville, AR (United States); Lara, Antonio [Universidad Austral de Chile, Laboratorio de Dendrocronologia, Facultad de Ciencias Forestales y Recursos Naturales, Valdivia (Chile); Universidad Austral de Chile, Forest Ecosystem Services under Climatic Fluctuations (Forecos), Valdivia (Chile); Mudelsee, Manfred [Climate Risk Analysis, Hanover (Germany); Alfred Wegener Institute for Polar and Marine Research, Bremerhaven (Germany)

2011-04-15

The Andes Cordillera acts as regional ''Water Towers'' for several countries and encompasses a wide range of ecosystems and climates. Several hydroclimatic changes have been described for portions of the Andes during recent years, including glacier retreat, negative precipitation trends, an elevation rise in the 0 isotherm, and changes in regional streamflow regimes. The Temperate-Mediterranean transition (TMT) zone of the Andes (35.5 -39.5 S) is particularly at risk to climate change because it is a biodiversity hotspot with heavy human population pressure on water resources. In this paper we utilize a new tree-ring network of Austrocedrus chilensis to reconstruct past variations in regional moisture in the TMT of the Andes by means of the Palmer Drought Severity Index (PDSI). The reconstruction covers the past 657 years and captures interannual to decadal scales of variability in late spring-early summer PDSI. These changes are related to the north-south oscillations in moisture conditions between the Mediterranean and Temperate climates of the Andes as a consequence of the latitudinal position of the storm tracks forced by large-scale circulation modes. Kernel estimation of occurrence rates reveals an unprecedented increment of severe and extreme drought events during the last century in the context of the previous six centuries. Moisture conditions in our study region are linked to tropical and high-latitude ocean-atmospheric forcing, with PDSI positively related to Nino-3.4 SST during spring and strongly negatively correlated with the Antarctic Oscillation (AAO) during summer. Geopotential anomaly maps at 500-hPa show that extreme dry years are tightly associated with negative height anomalies in the Ross-Amundsen Seas, in concordance with the strong negative relationship between PDSI and AAO. The twentieth century increase in extreme drought events in the TMT may not be related to ENSO but to the positive AAO trend during late-spring and

Classification of Snowfall Events and Their Effect on Canopy Interception Efficiency in a Temperate Montane Forest.

Science.gov (United States)

Roth, T. R.; Nolin, A. W.

2015-12-01

Forest canopies intercept as much as 60% of snowfall in maritime environments, while processes of sublimation and melt can reduce the amount of snow transferred from the canopy to the ground. This research examines canopy interception efficiency (CIE) as a function of forest and event-scale snowfall characteristics. We use a 4-year dataset of continuous meteorological measurements and monthly snow surveys from the Forest Elevation Snow Transect (ForEST) network that has forested and open sites at three elevations spanning the rain-snow transition zone to the upper seasonal snow zone. Over 150 individual storms were classified by forest and storm type characteristics (e.g. forest density, vegetation type, air temperature, snowfall amount, storm duration, wind speed, and storm direction). The between-site comparisons showed that, as expected, CIE was highest for the lower elevation (warmer) sites with higher forest density compared with the higher elevation sites where storm temperatures were colder, trees were smaller and forests were less dense. Within-site comparisons based on storm type show that this classification system can be used to predict CIE.Our results suggest that the coupling of forest type and storm type information can improve estimates of canopy interception. Understanding the effects of temperature and storm type in temperate montane forests is also valuable for future estimates of canopy interception under a warming climate.

Predicting Plant-Accessible Water in the Critical Zone: Mountain Ecosystems in a Mediterranean Climate

Science.gov (United States)

Klos, P. Z.; Goulden, M.; Riebe, C. S.; Tague, C.; O'Geen, A. T.; Flinchum, B. A.; Safeeq, M.; Conklin, M. H.; Hart, S. C.; Asefaw Berhe, A.; Hartsough, P. C.; Holbrook, S.; Bales, R. C.

2017-12-01

Enhanced understanding of subsurface water storage, and the below-ground architecture and processes that create it, will advance our ability to predict how the impacts of climate change - including drought, forest mortality, wildland fire, and strained water security - will take form in the decades to come. Previous research has examined the importance of plant-accessible water in soil, but in upland landscapes within Mediterranean climates the soil is often only the upper extent of subsurface water storage. We draw insights from both this previous research and a case study of the Southern Sierra Critical Zone Observatory to: define attributes of subsurface storage, review observed patterns in its distribution, highlight nested methods for its estimation across scales, and showcase the fundamental processes controlling its formation. We observe that forest ecosystems at our sites subsist on lasting plant-accessible stores of subsurface water during the summer dry period and during multi-year droughts. This indicates that trees in these forest ecosystems are rooted deeply in the weathered, highly porous saprolite, which reaches up to 10-20 m beneath the surface. This confirms the importance of large volumes of subsurface water in supporting ecosystem resistance to climate and landscape change across a range of spatiotemporal scales. This research enhances the ability to predict the extent of deep subsurface storage across landscapes; aiding in the advancement of both critical zone science and the management of natural resources emanating from similar mountain ecosystems worldwide.

Adaptive root foraging strategies along a boreal–temperate forest gradient

Czech Academy of Sciences Publication Activity Database

Ostonen, I.; Truu, M.; Helmisaari, H.-S.; Lukač, M.; Borken, W.; Vanguelova, H.; Godbold, Douglas; Löhmus, K.; Zang, U.; Tedersoo, L.; Preem, J.-K.; Rosenvald, K.; Aosaar, J.; Armolaitis, K.; Frey, J.; Kabral, N.; Kukumägi, M.; Leppälammi-Kujansuu, J.; Lindroos, A.-J.; Merila, P.; Napa, Ü.; Nöjd, P.; Parts, K.; Uri, V.; Varik, M.; Truu, J.

2017-01-01

Roč. 215, č. 3 (2017), s. 977-991 ISSN 0028-646X EU Projects: European Commission(XE) 315982; European Commission(XE) 315982; European Commission(XE) 90/E38 Institutional support: RVO:67179843 Keywords : boreal and temperate forests * climate gradient * ectomycorrhizal (EcM) mycelium * fine and ectomycorrhizal root biomass * root foraging * root morphology * soil and rhizosphere bacteria * soil C * N ratio Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 7.330, year: 2016

Tropical Malaysians and temperate Koreans exhibit significant differences in sweating sensitivity in response to iontophoretically administered acetylcholine

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Lee, Jeong-Beom; Bae, Jun-Sang; Matsumoto, Takaaki; Yang, Hun-Mo; Min, Young-Ki

2009-03-01

Natives of the tropics are able to tolerate high ambient temperatures. This results from their long-term residence in hot and often humid tropical climates. This study was designed to compare the peripheral mechanisms of thermal sweating in tropical natives with that of their temperate counterparts. Fifty-five healthy male subjects including 20 native Koreans who live in the temperate Korean climate (Temperate-N) and 35 native tropical Malaysian men that have lived all of their lives in Malaysia (Tropical-N) were enrolled in this study after providing written informed consent to participate. Quantitative sudomotor axon reflex testing after iontophoresis (2 mA for 5 min) with 10% acetylcholine (ACh) was used to determine directly activated (DIR) and axon reflex-mediated (AXR) sweating during ACh iontophoresis. The sweat rate, activated sweat gland density, sweat gland output per single gland activated, and oral and skin temperature changes were measured. The sweat onset time of AXR (nicotinic-receptor-mediated) was 56 s shorter in the Temperate-N than in the Tropical-N subjects ( P < 0.0001). The nicotinic-receptor-mediated sweating activity AXR (1), and the muscarinic-receptor-mediated sweating activity DIR, in terms of sweat volume, were 103% and 59% higher in the Temperate-N compared to the Tropical-N subjects ( P < 0.0001). The Temperate-N group also had a 17.8% ( P < 0.0001) higher active sweat gland density, 35.4% higher sweat output per gland, 0.24°C higher resting oral temperature, and 0.62°C higher resting forearm skin temperature compared to the Tropical-N subjects ( P < 0.01). ACh iontophoresis did not influence oral temperature, but increased skin temperature near where the ACh was administered, in both groups. These results suggest that suppressed thermal sweating in the Tropical-N subjects was, at least in part, due to suppressed sweat gland sensitivity to ACh through both recruitment of active sweat glands and the sweat gland output per each gland

Seasonal and inter-annual variability of the net ecosystem CO2 exchange of a temperate mountain grassland: effects of climate and management.

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Wohlfahrt, Georg; Hammerle, Albin; Haslwanter, Alois; Bahn, Michael; Tappeiner, Ulrike; Cernusca, Alexander

2008-04-27

The role and relative importance of climate and cutting for the seasonal and inter-annual variability of the net ecosystem CO 2 (NEE) of a temperate mountain grassland was investigated. Eddy covariance CO 2 flux data and associated measurements of the green area index and the major environmental driving forces acquired during 2001-2006 at the study site Neustift (Austria) were analyzed. Driven by three cutting events per year which kept the investigated grassland in a stage of vigorous growth, the seasonal variability of NEE was primarily modulated by gross primary productivity (GPP). The role of environmental parameters in modulating the seasonal variability of NEE was obscured by the strong response of GPP to changes in the amount of green area, as well as the cutting-mediated decoupling of phenological development and the seasonal course of climate drivers. None of the climate and management metrics examined was able to explain the inter-annual variability of annual NEE. This is thought to result from (1) a high covariance between GPP and ecosystem respiration (R eco ) at the annual time scale which results in a comparatively small inter-annual variation of NEE, (2) compensating effects between carbon exchange during and outside the management period, and (3) changes in the biotic response to rather than the climate variables per se. GPP was more important in modulating inter-annual variations in NEE in spring and before the first and second cut, while R eco explained a larger fraction of the inter-annual variability of NEE during the remaining, in particular the post-cut, periods.

Agro-climatic zoning of Jatropha curcas as a subside for crop planning and implementation in Brazil.

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Yamada, Eliane S M; Sentelhas, Paulo C

2014-11-01

As jatropha (Jatropha curcas L.) is a recent crop in Brazil, the studies for defining its suitability for different regions are not yet available, even considering the promises about this plant as of high potential for marginal zones where poor soils and dry climate occur. Based on that, the present study had as objective to characterize the climatic conditions of jatropha's center of origin in Central America for establishing its climatic requirements and to develop the agro-climatic zoning for this crop for some Brazilian regions where, according to the literature, it would be suitable. For classifying the climatic conditions of the jatropha's center of origin, climate data from 123 weather stations located in Mexico (93) and in Guatemala (30) were used. These data were input for Thornthwaite and Mather's climatological water balance for determining the annual water deficiency (WD) and water surplus (WS) of each location, considering a soil water-holding capacity (SWHC) of 100 mm. Mean annual temperature (T m), WD, and WS data were organized in histograms for defining the limits of suitability for jatropha cultivation. The results showed that the suitable range of T m for jatropha cultivation is between 23 and 27 °C. T m between 15 and 22.9 °C and between 27.1 and 28 °C were classified as marginal by thermal deficiency and excess, respectively. T m below 15 °C and above 28 °C were considered as unsuitable for jatropha cultivation, respectively, by risk of frosts and physiological disturbs. For WD, suitability for rain-fed jatropha cultivation was considered when its value is below 360 mm, while between 361 and 720 mm is considered as marginal and over 720 mm unsuitable. The same order of suitability was also defined for WS, with the following limits: suitable for WS up to 1,200 mm; marginal for WS between 1,201 and 2,400 mm, and unsuitable for WS above 2,400 mm. For the crop zoning, the criteria previously defined were applied to 1,814 climate stations in

Emerging Forms of Climate Protection Governance: Urban Initiatives in the European Union

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Rosenthal, J. K.; Brunner, E.

2006-12-01

Changes in climate patterns are expected to pose increasing challenges for cities in the following decades, with adverse impacts on urban populations currently stressed by poverty, health and economic inequities. Simultaneously, a strong global trend towards urbanization of poverty exists, with increased challenges for local governments to protect and sustain the well-being of growing cities. In the context of these two overarching trends, interdisciplinary research at the city scale is prioritized for understanding the social impacts of climate change and variability and for the evaluation of strategies in the built environment that might serve as adaptive and mitigative responses to climate change. Urban managers, and transnational networks of municipalities and non-state actors, have taken an increasingly active role in climate protection, through research, policies, programs and agreements on adaptation and mitigation strategies. Concerns for urban impacts of climate change include the potential increase in frequency and intensity of damaging extreme weather events, such as heat waves, hurricanes, heavy rainfall or drought, and coastal flooding and erosion, and potentially adverse impacts on infrastructure, energy systems, and public health. Higher average summertime temperatures in temperate zone cities are also associated with environmental and public health liabilities such as decreased air quality and increased peak electrical demand. We review municipal climate protection programs, generally categorized as approaches based on technological innovation (e.g., new materials); changes in behavior and public education (e.g., use of cooling centers); and improvements in urban design (e.g., zoning for mixed land-use; the use of water, vegetation and plazas to reduce the urban heat island effect). Climate protection initiatives in three European cities are assessed within the context of the global collective efforts enacted by the Kyoto Protocol and United Nations

Climate Shifts and the Role of Nano Structured Particles in the Atmosphere

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Ursem, W.N.J.

2015-01-01

A global net sum equilibrium in heat exchange is a fact and thus a global climate change doesn’t exist, but climate shifts in climate cells, especially in the northern temperate cell, do. The global climate has been ever since homeostatic, and has recuperated far huger climate impacts in the past.

The interactive effects of soil transplant into colder regions and cropping on soil microbiology and biogeochemistry.

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Liu, Shanshan; Wang, Feng; Xue, Kai; Sun, Bo; Zhang, Yuguang; He, Zhili; Van Nostrand, Joy D; Zhou, Jizhong; Yang, Yunfeng

2015-03-01

Soil transplant into warmer regions has been shown to alter soil microbiology. In contrast, little is known about the effects of soil transplant into colder regions, albeit that climate cooling has solicited attention in recent years. To address this question, we transplanted bare fallow soil over large transects from southern China (subtropical climate zone) to central (warm temperate climate zone) and northern China (cold temperate climate zone). After an adaptation period of 4 years, soil nitrogen components, microbial biomass and community structures were altered. However, the effects of soil transplant on microbial communities were dampened by maize cropping, unveiling a negative interaction between cropping and transplant. Further statistical analyses with Canonical correspondence analysis and Mantel tests unveiled annual average temperature, relative humidity, aboveground biomass, soil pH and NH4 (+) -N content as environmental attributes closely correlated with microbial functional structures. In addition, average abundances of amoA-AOA (ammonia-oxidizing archaea) and amoA-AOB (ammonia-oxidizing bacteria) genes were significantly (P Microbiology and John Wiley & Sons Ltd.

Adaptive root foraging strategies along a boreal-temperate forest gradient.

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Ostonen, Ivika; Truu, Marika; Helmisaari, Heljä-Sisko; Lukac, Martin; Borken, Werner; Vanguelova, Elena; Godbold, Douglas L; Lõhmus, Krista; Zang, Ulrich; Tedersoo, Leho; Preem, Jens-Konrad; Rosenvald, Katrin; Aosaar, Jürgen; Armolaitis, Kęstutis; Frey, Jane; Kabral, Naima; Kukumägi, Mai; Leppälammi-Kujansuu, Jaana; Lindroos, Antti-Jussi; Merilä, Päivi; Napa, Ülle; Nöjd, Pekka; Parts, Kaarin; Uri, Veiko; Varik, Mats; Truu, Jaak

2017-08-01

The tree root-mycorhizosphere plays a key role in resource uptake, but also in the adaptation of forests to changing environments. The adaptive foraging mechanisms of ectomycorrhizal (EcM) and fine roots of Picea abies, Pinus sylvestris and Betula pendula were evaluated along a gradient from temperate to subarctic boreal forest (38 sites between latitudes 48°N and 69°N) in Europe. Variables describing tree resource uptake structures and processes (absorptive fine root biomass and morphology, nitrogen (N) concentration in absorptive roots, extramatrical mycelium (EMM) biomass, community structure of root-associated EcM fungi, soil and rhizosphere bacteria) were used to analyse relationships between root system functional traits and climate, soil and stand characteristics. Absorptive fine root biomass per stand basal area increased significantly from temperate to boreal forests, coinciding with longer and thinner root tips with higher tissue density, smaller EMM biomass per root length and a shift in soil microbial community structure. The soil carbon (C) : N ratio was found to explain most of the variability in absorptive fine root and EMM biomass, root tissue density, N concentration and rhizosphere bacterial community structure. We suggest a concept of absorptive fine root foraging strategies involving both qualitative and quantitative changes in the root-mycorrhiza-bacteria continuum along climate and soil C : N gradients. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Climate and Vegetation Effects on Temperate Mountain Forest Evapotranspiration

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Current forest composition may be resilient to typical climatic variability; however, climate trends, combined with projected changes in species composition, may increase tree vulnerability to water stress. A shift in forest composition toward tree species with higher water use h...

Early stages of formation and dispersal of the temperate flora in the Boreal region

International Nuclear Information System (INIS)

Budantsev, L.Y.

1992-01-01

The thesis of this review is that the composition of a flora can be understood only as a process, or separate stage, in the context of migration in time and space of various floristic assemblages and their isolation, as induced by transformation of continental and ocean shapes, changes in climate, and the environment as a whole. Thus the formation of geofloras of the past was influenced by gradually changing environments that determined the spread, patterning, and spatial differentiation of floras and their evolution. Parallel to the more commonly-seen names of eras-Paleozoic, Mesozoic, and Cenozoic-we can speak of the Paleophytic, Mesophytic, and Cenophytic eras. Eras defined in these two ways (by faunistic or by floristic criteria) do not completely coincide. Generally, changes in the flora have, necessarily, preceded changes in the fauna. It is the Cenophytic with which this review is mostly concerned, the era of Angiosperm dominance. The movement of early subtropical and warm temperate floras in the Early Cenophytic, followed by temperate or even boreal floras, as the climate changes, is traced in detail

The geology of selected peat-forming environments in temperate and tropical latitudes

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Cameron, C.C.; Palmer, C.A.; Esterle, J.S.

1990-01-01

We studied peat in several geologic and climatic settings: (1) a glaciated terrain in cold-temperate Maine and Minnesota, U.S.A.; (2) an island in a temperate maritime climate in the Atlantic Ocean off the coast of Maine, U.S.A., where sea level is rising rapidly and changing the environment of peat accumulation; (3) swamps along the warm-temperate U.S. Atlantic and Gulf Coastal Plains, where sea level has changed often, thus creating sites for accumulation; and (4) in a tropical climate along the coast of Sarawak, Malaysia, and the delta of the Batang Hari River, Sumatra, Indonesia (Figs. 1 and 2). With the exception of the deposits on the Atlantic and Gulf Coastal Plains, most of the deposits described are domed bogs in which peat accumulation continued above the surface of the surrounding soil. The bogs of the U.S. Atlantic and Gulf Coastal Plains have almost level surfaces. All domed bogs are not entirely ombrotrophic (watered only from precipitation); multidomed bogs that rise from irregular or hilly surfaces may be crossed by streams that supply water to the bogs. The geologic processes or organic sedimentation, namely terrestrialization and paludification, are similar in all peat deposits considered here. Differences in geomorphology affecting the quantity and that quality of peat that has ash contents of less than 25%, which are desirable for commercial purposes, depend chiefly on: (1) high humidity, which is favorable to luxuriant growth of peat-forming vegetation; (2) a depositional setting that permits extensive accumulation relatively free from inorganic contamination from sea water and streams and from dust and volcanic ash; and (3) a stable regional water table that controls the rate of decomposition under aerobic conditions and protects the deposit against the ravages of fire. Differences in peat textures are due to the type of vegetation and to the degree of decomposition. The rate of decomposition is largely the result of the amount of oxidation

Acidity and origin of dissolved organic carbon in different vegetation zones

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Hruška, Jakub; Oulehle, Filip; Myška, Oldřích; Chuman, Tomáš

2016-04-01

The acid/base character of aquatic dissolved organic carbon (DOC) has been studied intensively during recent decades with regard to the role of DOC in stream water acidity and the balance between natural acidity and anthropogenic acidification. Recently, DOC has been shown to play an important role in preindustrial surface waters. Studies focused on the acid/base properties of DOC have been carried out in mainly in Europe and North America and paint a conflicting picture. Some studies reported large differences in acid base properties, sometimes between quite similar and nearby localities, or between seasons at the same site. Other studies, however, found similar acid/base properties in waters from a variety of sites, sometimes far from each other as well as stable acid/base properties at the same site through different seasons or runoff events. Site density of DOC (amount of carboxylic groups per milligram of DOC) and SUVA was measured for streams (or small tundra ponds respectively) from the tundra in northern Alaska, boreal zone of Sweden, western Czech Republic (temperate region), and tropical Congo rain forest in central Africa. At least 10 samples from each region were taken from surface waters during the growing season. Titration of carboxylic groups after proton saturation on cation-exchange resin was used for site density determination. Despite very different climatic and vegetation properties and internal variation within a region, there was no statistically significant difference among regions for site density (it varied between 10.2-10.5 ueq/mg DOC) as well as for SUVA (tested by ANOVA). Results suggest that different vegetation and climate produced generally the same DOC in respect of acid/base character and SUVA. It also suggests that use of the one analytical technique was more important than differences between climatic zones itself.

Microevolution of European temperate oaks in response to environmental changes.

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Kremer, Antoine

2016-01-01

This review reconstructs microevolutionary processes that allowed long-lived species as temperate oaks (Quercus petraea and Q. robur) to cope with climate change since the last glacial maximum, by assembling insights from complementary synchronic and allochronic approaches. Paleobotanical and genetic investigations show that oaks migrated at larger velocities than expected, thanks to long-distance rare events and most likely human interferences. Hybridization was a key mechanism accelerating migration and enhancing species succession. Common garden experiments and genome wide association studies demonstrated that diversifying selection across large environmental gradients contributed to rapid local adaptation. Finally the review explores how lessons taken from past evolutionary scenarios may help to predict future responses of oaks to ongoing climate change. Copyright © 2016. Published by Elsevier SAS.

Climate variability and environmental stress in the Sudan-Sahel zone of West Africa

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Mertz, Ole; D'haen, Sarah Ann Lise; Maiga, Abdou

2012-01-01

Environmental change in the Sudan-Sahel region of West Africa (SSWA) has been much debated since the droughts of the 1970s. In this article we assess climate variability and environmental stress in the region. Households in Senegal, Mali, Burkina Faso, Niger, and Nigeria were asked about climatic...... to household perceptions, observed rainfall patterns showed an increasing trend over the past 20 years. However, August rainfall declined, and could therefore potentially explain the contrasting negative household perceptions of rainfall trends. Most households reported degradation of soils, water resources......, vegetation, and fauna, but more so in the 500–900 mm zones. Adaptation measures to counter environmental degradation included use of manure, reforestation, soil and water conservation, and protection of fauna and vegetation. The results raise concerns for future environmental management in the region...

Impact of global warming on performance of ground source heat pumps in US climate zones

International Nuclear Information System (INIS)

Shen, Pengyuan; Lukes, Jennifer R.

2015-01-01

Highlights: • Used morphing method to have downscaled hourly local weather data from GCM. • Selected representative cities in different climate zones in the US for case study on GSHP performance. • Used hourly building simulation tools (eQuest and TRNSYS) to project GSHP performance in future. • Analysis on GSHP performance in 2050 for both residential and office building in the US are conducted. - Abstract: Ground source heat pumps (GSHP) have attracted increasing attention because of their high energy efficiencies. The aim of this paper is to study the performance of (GSHP) in future climate conditions (2040–2069) by using projected future hourly weather data of selected representative cities in the US to estimate future ground temperature change. The projected hourly weather data and estimated ground temperatures are input to an hourly simulation tool (TRNSYS and eQuest for this research), which provides reliable coupling of GSHP system and building performance. The simulation results show that global warming will decrease the energy efficiency of GSHP in US residential buildings because a rise in inlet and outlet water temperature is predicted for GSHP systems during the cooling season and because buildings will become more cooling dominated in the future. For office buildings, although the cooling performance of GSHP will not drop significantly under future climate, the overall energy efficiency for the system will decrease due to the increasing energy consumption of the ground loop pump. In the future, considering the significant ground heat imbalance for GSHP operation, GSHP will become less competitive both economically and technically than it is now in the context of US climate zones

Plasmodium vivax populations revisited: mitochondrial genomes of temperate strains in Asia suggest ancient population expansion

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Miao Miao

2012-02-01

Full Text Available Abstract Background Plasmodium vivax is the most widely distributed human malaria parasite outside of Africa, and its range extends well into the temperate zones. Previous studies provided evidence for vivax population differentiation, but temperate vivax parasites were not well represented in these analyses. Here we address this deficit by using complete mitochondrial (mt genome sequences to elucidate the broad genetic diversity and population structure of P. vivax from temperate regions in East and Southeast Asia. Results From the complete mtDNA sequences of 99 clinical samples collected in China, Myanmar and Korea, a total of 30 different haplotypes were identified from 26 polymorphic sites. Significant differentiation between different East and Southeast Asian parasite populations was observed except for the comparison between populations from Korea and southern China. Haplotype patterns and structure diversity analysis showed coexistence of two different groups in East Asia, which were genetically related to the Southeast Asian population and Myanmar population, respectively. The demographic history of P. vivax, examined using neutrality tests and mismatch distribution analyses, revealed population expansion events across the entire P. vivax range and the Myanmar population. Bayesian skyline analysis further supported the occurrence of ancient P. vivax population expansion. Conclusions This study provided further resolution of the population structure and evolution of P. vivax, especially in temperate/warm-temperate endemic areas of Asia. The results revealed divergence of the P. vivax populations in temperate regions of China and Korea from other populations. Multiple analyses confirmed ancient population expansion of this parasite. The extensive genetic diversity of the P. vivax populations is consistent with phenotypic plasticity of the parasites, which has implications for malaria control.

Effects of Climate on Co-evolution of Weathering Profiles and Hillscapes

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Anderson, R. S.; Rajaram, H.; Anderson, S. P.

2017-12-01

Considerable debate revolves around the relative importance of rock type, tectonics, and climate in creating the architecture of the critical zone. It has recently been proposed that differences in the depths and patterns of weathering between landscapes in Colorado's Front Range and South Carolina's piedmont can be attributed to the state of stress in the rock imposed by the magnitude and orientation the regional stresses with respect to the ridgelines (St. Claire et al., 2016). We argue for the importance of the climate, and in particular, in temperate regions, the amount of recharge. We employ numerical models of hillslope evolution between bounding erosional channels, in which the degree of rock weathering governs the rate of transformation of rock to soil. As the water table drapes between the stream channels, fresh rock is brought into the weathering zone at a rate governed by the rate of incision of the channels. We track the chemical weathering of rock, represented by alteration of feldspar to clays, which in turn requires calculation of the concentration of reactive species in the water along hydrologic flow paths. We present results from analytic solutions to the flow field in which travel times can be efficiently assessed. Below the water table, flow paths are hyperbolic, taking on considerable lateral components as they veer toward the bounding channels that serve as drains to the hillslope. We find that if water is far from equilibrium with respect to weatherable minerals at the water table, as occurs in wet, slowly-eroding landscapes, deep weathering can occur well below the water table to levels approximating the base of the bounding channels. In dry climates, on the other hand, the weathering zone is limited to a shallow surface - parallel layer. These models capture the essence of the observed differences in depth to fresh rock in both wet and dry climates without appeal to the state of stress in the rock.

Winter warming delays dormancy release, advances budburst, alters carbohydrate metabolism and reduces yield in a temperate shrub

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Pagter, Majken; Andersen, Uffe Brandt; Andersen, Lillie

2015-01-01

Global climate models predict an increase in the mean surface air temperature, with a disproportionate increase during winter. Since temperature is a major driver of phenological events in temperate woody perennials, warming is likely to induce changes in a range of these events. We investigated ...

Does climate undermine subjective well-being? A 58-nation study.

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Fischer, Ronald; Van de Vliert, Evert

2011-08-01

The authors test predictions from climato-economic theories of culture that climate and wealth interact in their influence on psychological processes. Demanding climates (defined as colder than temperate and hotter than temperate climates) create potential threats for humans. If these demands can be met by available economic resources, individuals experience challenging opportunities for self-expression and personal growth and consequently will report lowest levels of ill-being. If threatening climatic demands cannot be met by resources, resulting levels of reported ill-being will be highest. These predictions are confirmed in nation-level means of health complaints, burnout, anxiety, and depression across 58 societies. Climate, wealth, and their interaction together account for 35% of the variation in overall subjective ill-being, even when controlling for known predictors of subjective well-being. Further investigations of the process suggest that cultural individualism does not mediate these effects, but subjective well-being may function as a mediator of the impact of ecological variables on ill-being.

Potential climate change impacts on temperate forest ecosystem processes

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Peters, Emily B.; Wythers, Kirk R.; Zhang, Shuxia; Bradford, John B.; Reich, Peter B.

2013-01-01

Large changes in atmospheric CO2, temperature and precipitation are predicted by 2100, yet the long-term consequences for carbon, water, and nitrogen cycling in forests are poorly understood. We applied the PnET-CN ecosystem model to compare the long-term effects of changing climate and atmospheric CO2 on productivity, evapotranspiration, runoff, and net nitrogen mineralization in current Great Lakes forest types. We used two statistically downscaled climate projections, PCM B1 (warmer and wetter) and GFDL A1FI (hotter and drier), to represent two potential future climate and atmospheric CO2 scenarios. To separate the effects of climate and CO2, we ran PnET-CN including and excluding the CO2 routine. Our results suggest that, with rising CO2 and without changes in forest type, average regional productivity could increase from 67% to 142%, changes in evapotranspiration could range from –3% to +6%, runoff could increase from 2% to 22%, and net N mineralization could increase 10% to 12%. Ecosystem responses varied geographically and by forest type. Increased productivity was almost entirely driven by CO2 fertilization effects, rather than by temperature or precipitation (model runs holding CO2 constant showed stable or declining productivity). The relative importance of edaphic and climatic spatial drivers of productivity varied over time, suggesting that productivity in Great Lakes forests may switch from being temperature to water limited by the end of the century.

Nitrogen cycling in heathland ecosystems and effects of climate change

DEFF Research Database (Denmark)

Andresen, Louise Christoffersen

Terrestrial ecosystems are currently exposed to climatic and air quality changes with increased atmospheric CO2, increased temperature and periodical droughts. At a temperate heath site this was investigated in a unique full factorial in situ experiment (CLIMAITE). The climate change treatments...

Climate change and their consequences on coastal zone of Ain el Turck in Oran

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Mohammed Tewfik Bouroumi

2017-12-01

Full Text Available Algeria does not escape the problem of the climate change, its geographical position in zone of transition, and its dry and semi-arid climate, in fact a very vulnerable space. In Algeria, approximately two thirds of the population is concentrated on the coast which represents only 4 % of the territory. The Mediterranean coast, in particular in Algeria, is subjected to pressures: financial stakes, climatic risks, pollutions and conservation of the water. It is on the basis of the critical and objective report with regard to a wild urbanization of the Algerian coast as well as the influence of the demographic pressure that the choice of the search for this article was held. This publication has for objective to raise (to draw up a current situation (inventory of fixtures of the sector of the environment in Algeria and to present through the case of the coastal city of Oran the consequences of climate change. We propose, to review the situation through the case of the municipality of Ain El Türck, by basing itself on data relative to the evolution of the temperatures and the sea level.

Predicting Future Seed Sourcing of Platycladus orientalis (L. for Future Climates Using Climate Niche Models

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Xian-Ge Hu

2017-12-01

Full Text Available Climate niche modeling has been widely used to assess the impact of climate change on forest trees at the species level. However, geographically divergent tree populations are expected to respond differently to climate change. Considering intraspecific local adaptation in modeling species responses to climate change will thus improve the credibility and usefulness of climate niche models, particularly for genetic resources management. In this study, we used five Platycladus orientalis (L. seed zones (Northwestern; Northern; Central; Southern; and Subtropical covering the entire species range in China. A climate niche model was developed and used to project the suitable climatic conditions for each of the five seed zones for current and various future climate scenarios (Representative Concentration Pathways: RCP2.6, RCP4.5, RCP6.0, and RCP8.5. Our results indicated that the Subtropical seed zone would show consistent reduction for all climate change scenarios. The remaining seed zones, however, would experience various degrees of expansion in suitable habitat relative to their current geographic distributions. Most of the seed zones would gain suitable habitats at their northern distribution margins and higher latitudes. Thus, we recommend adjusting the current forest management strategies to mitigate the negative impacts of climate change.

Seasonality of temperate forest photosynthesis and daytime respiration.

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Wehr, R; Munger, J W; McManus, J B; Nelson, D D; Zahniser, M S; Davidson, E A; Wofsy, S C; Saleska, S R

2016-06-30

Terrestrial ecosystems currently offset one-quarter of anthropogenic carbon dioxide (CO2) emissions because of a slight imbalance between global terrestrial photosynthesis and respiration. Understanding what controls these two biological fluxes is therefore crucial to predicting climate change. Yet there is no way of directly measuring the photosynthesis or daytime respiration of a whole ecosystem of interacting organisms; instead, these fluxes are generally inferred from measurements of net ecosystem-atmosphere CO2 exchange (NEE), in a way that is based on assumed ecosystem-scale responses to the environment. The consequent view of temperate deciduous forests (an important CO2 sink) is that, first, ecosystem respiration is greater during the day than at night; and second, ecosystem photosynthetic light-use efficiency peaks after leaf expansion in spring and then declines, presumably because of leaf ageing or water stress. This view has underlain the development of terrestrial biosphere models used in climate prediction and of remote sensing indices of global biosphere productivity. Here, we use new isotopic instrumentation to determine ecosystem photosynthesis and daytime respiration in a temperate deciduous forest over a three-year period. We find that ecosystem respiration is lower during the day than at night-the first robust evidence of the inhibition of leaf respiration by light at the ecosystem scale. Because they do not capture this effect, standard approaches overestimate ecosystem photosynthesis and daytime respiration in the first half of the growing season at our site, and inaccurately portray ecosystem photosynthetic light-use efficiency. These findings revise our understanding of forest-atmosphere carbon exchange, and provide a basis for investigating how leaf-level physiological dynamics manifest at the canopy scale in other ecosystems.

Global analysis of threat status reveals higher extinction risk in tropical than in temperate bird sister species

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Reif Jiří

2016-06-01

Full Text Available Given increasing pressures upon biodiversity, identification of species’ traits related to elevated extinction risk is useful for more efficient allocation of limited resources for nature conservation. Despite its need, such a global analysis was lacking in the case of birds. Therefore, we performed this exercise for avian sister species using information about their global extinction risk from IUCN Red List. We focused on 113 pairs of sister species, each containing a threatened and an unthreatened species to factor out the effects of common evolutionary history on the revealed relationship. We collected data on five traits with expected relationships to species’ extinction risk based on previous studies performed at regional or national levels: breeding habitat (recognizing forest, grassland, wetland and oceanic species, latitudinal range position (temperate and tropics species, migration strategy (migratory and resident species, diet (carnivorous, insectivorous, herbivorous and omnivorous species and body mass. We related the extinction risk using IUCN threat level categories to species’ traits using generalised linear mixed effects models expecting lower risk for forest, temperate, omnivorous and smaller-bodied species. Our expectation was confirmed only in the case of latitudinal range position, as we revealed higher threat level for tropical than for temperate species. This relationship was robust to different methods of threat level expression and cannot be explained by a simple association of high bird species richness with the tropical zone. Instead, it seems that tropical species are more threatened because of their intrinsic characteristics such as slow life histories, adaptations to stable environments and small geographic ranges. These characteristics are obviously disadvantageous in conditions of current human-induced environmental perturbations. Moreover, given the absence of habitat effects, our study indicates that such

Policy frameworks for adaptation to climate change in coastal zones. The case of the Gulf of Mexico

International Nuclear Information System (INIS)

Levina, E.; Jacob, J.S.; Ramos Bustillos, L.E.; Ortiz, I.

2007-05-01

This paper is the third in a series of AIXG (Annex I Expert Group on the United Nations Framework Convention on Climate Change (UNFCCC)) papers that analyse the roles that national policy frameworks of various sectors play in adaptation to climate change. Adaptation to climate change is unlikely to be a standalone process. It occurs within the existing sectoral and cross-sectoral policy frameworks, including legal provisions, institutional structures, policies and management practices, and is supported by the available information tools. The previous two papers focused on the water sector. The aim of this paper is to identify and analyse policy frameworks that are important for facilitating adaptation to climate change impacts in coastal zones. The paper is based on the analysis of the Gulf of Mexico. Two countries, the US and Mexico, are examined, with a focus on two aspects of coastal zones: wetlands and built environment. Next to these two sectors attention is paid to four components that construct policy frameworks, namely legal framework, institutional landscape, policies and management tools, and information. Following a brief introduction of the Gulf of Mexico region, its physical and economic characteristics, the paper takes a look at current climatic conditions and trends in the Gulf region and expected climate change impacts and the key vulnerabilities of the region to these changes (Section 2). The rational for the scope and focus of the sectoral analysis presented in this paper can also be found in Section 2. Section 3 focuses on the analysis of policy frameworks that govern wetlands in the US and Mexico and their links with adaptation. Section 4 focuses on the analysis of policy frameworks that govern the development of human settlements, and adaptation to climate change. Sections 3 and 4 follow a structure similar to the one that was used for the two previous papers on policy frameworks for adaptation in the water sector. Both sections examine

[Climate- and vector-borne diseases

DEFF Research Database (Denmark)

Bygbjerg, I.C.; Schioler, K.L.; Konradsen, F.

2009-01-01

The predicted changes in climate have raised concerns that vector-borne diseases may emerge or expand in tempered regions. Malaria, leishmaniasis and tick-borne illnesses are discussed in terms of climate change and their endemic potential, especially in Denmark. While climate may play an important...... role in disease patterns, it is evident that transmission potential is governed by a complex of factors, including socio-economy, health-care capacity and ecology. In Denmark, malaria and leishmaniasis are unlikely to become public health problems, whereas the potential for tick-borne illnesses may...

Common garden comparison of the leaf-out phenology of woody species from different native climates, combined with herbarium records, forecasts long-term change.

Science.gov (United States)

Zohner, Constantin M; Renner, Susanne S

2014-08-01

A well-timed phenology is essential for plant growth and reproduction, but species-specific phenological strategies are still poorly understood. Here, we use a common garden approach to compare biannual leaf-out data for 495 woody species growing outdoors in Munich, 90% of them not native to that climate regime. For three species, data were augmented by herbarium dates for 140-year-long time series. We further meta-analysed 107 temperate-zone woody species in which leaf-out cues have been studied, half of them also monitored here. Southern climate-adapted species flushed significantly later than natives, and photoperiod- and chilling- sensitive species all flushed late. The herbarium method revealed the extent of species-specific climate tracking. Our results forecast that: (1) a northward expansion of southern species due to climate warming will increase the number of late flushers in the north, counteracting documented and expected flushing time advances; and (2) photoperiod- and chilling-sensitive woody species cannot rapidly track climate warming. © 2014 John Wiley & Sons Ltd/CNRS.

Modeling complex effects of multiple environmental stresses on carbon dynamics of Mid-Atlantic temperate forests

Science.gov (United States)

Yude Pan; Richard Birdsey; John Hom; Kevin McCullough

2007-01-01

We used our GIS variant of the PnET-CN model to investigate changes of forest carbon stocks and fluxes in Mid-Atlantic temperate forests over the last century (1900-2000). Forests in this region are affected by multiple environmental changes including climate, atmospheric CO2 concentration, N deposition and tropospheric ozone, and extensive land disturbances. Our...

Evaluation and prioritization of rice production practices and constraints under temperate climatic conditions using Fuzzy Analytical Hierarchy Process (FAHP)

International Nuclear Information System (INIS)

Mir, S.A.; Padma, T.

2016-01-01

Due to overwhelming complex and vague nature of interactions between multiple factors describing agriculture, Multi-Criteria Decision Making (MCDM) methods are widely used from farm to fork to facilitate systematic and transparent decision support, figure out multiple decision outcomes and equip decision maker with confident decision choices in order to choose best alternative. This research proposes a Fuzzy Analytical Hierarchy Process (FAHP) based decision support to evaluate and prioritize important factors of rice production practices and constraints under temperate climatic conditions and provides estimate of weightings, which measure relative importance of critical factors of the crop under biotic, abiotic, socio-economic and technological settings. The results envisage that flood, drought, water logging, late sali, temperature and rainfall are important constraints. However, regulating transplantation time; maintaining planting density; providing training to the educated farmers; introducing high productive varieties like Shalimar Rice-1 and Jhelum; better management of nutrients, weeds and diseases are most important opportunities to enhance rice production in the region. Therefore, the proposed system supplements farmers with precise decision information about important rice production practices, opportunities and constraints.

Evaluation and prioritization of rice production practices and constraints under temperate climatic conditions using Fuzzy Analytical Hierarchy Process (FAHP

Directory of Open Access Journals (Sweden)

Shabir A. Mir

2016-12-01

Full Text Available Due to overwhelming complex and vague nature of interactions between multiple factors describing agriculture, Multi-Criteria Decision Making (MCDM methods are widely used from farm to fork to facilitate systematic and transparent decision support, figure out multiple decision outcomes and equip decision maker with confident decision choices in order to choose best alternative. This research proposes a Fuzzy Analytical Hierarchy Process (FAHP based decision support to evaluate and prioritize important factors of rice production practices and constraints under temperate climatic conditions and provides estimate of weightings, which measure relative importance of critical factors of the crop under biotic, abiotic, socio-economic and technological settings. The results envisage that flood, drought, water logging, late sali, temperature and rainfall are important constraints. However, regulating transplantation time; maintaining planting density; providing training to the educated farmers; introducing high productive varieties like Shalimar Rice-1 and Jhelum; better management of nutrients, weeds and diseases are most important opportunities to enhance rice production in the region. Therefore, the proposed system supplements farmers with precise decision information about important rice production practices, opportunities and constraints.

Evaluation and prioritization of rice production practices and constraints under temperate climatic conditions using Fuzzy Analytical Hierarchy Process (FAHP)

Energy Technology Data Exchange (ETDEWEB)

Mir, S.A.; Padma, T.

2016-07-01

Due to overwhelming complex and vague nature of interactions between multiple factors describing agriculture, Multi-Criteria Decision Making (MCDM) methods are widely used from farm to fork to facilitate systematic and transparent decision support, figure out multiple decision outcomes and equip decision maker with confident decision choices in order to choose best alternative. This research proposes a Fuzzy Analytical Hierarchy Process (FAHP) based decision support to evaluate and prioritize important factors of rice production practices and constraints under temperate climatic conditions and provides estimate of weightings, which measure relative importance of critical factors of the crop under biotic, abiotic, socio-economic and technological settings. The results envisage that flood, drought, water logging, late sali, temperature and rainfall are important constraints. However, regulating transplantation time; maintaining planting density; providing training to the educated farmers; introducing high productive varieties like Shalimar Rice-1 and Jhelum; better management of nutrients, weeds and diseases are most important opportunities to enhance rice production in the region. Therefore, the proposed system supplements farmers with precise decision information about important rice production practices, opportunities and constraints.

Climate extreme effects on the chemical composition of temperate grassland species under ambient and elevated CO2: a comparison of fructan and non-fructan accumulators.

Directory of Open Access Journals (Sweden)

Hamada AbdElgawad

Full Text Available Elevated CO2 concentrations and extreme climate events, are two increasing components of the ongoing global climatic change factors, may alter plant chemical composition and thereby their economic and ecological characteristics, e.g. nutritional quality and decomposition rates. To investigate the impact of climate extremes on tissue quality, four temperate grassland species: the fructan accumulating grasses Lolium perenne, Poa pratensis, and the nitrogen (N fixing legumes Medicago lupulina and Lotus corniculatus were subjected to water deficit at elevated temperature (+3°C, under ambient CO2 (392 ppm and elevated CO2 (620 ppm. As a general observation, the effects of the climate extreme were larger and more ubiquitous in combination with elevated CO2. The imposed climate extreme increased non-structural carbohydrate and phenolics in all species, whereas it increased lignin in legumes and decreased tannins in grasses. However, there was no significant effect of climate extreme on structural carbohydrates, proteins, lipids and mineral contents and stoichiometric ratios. In combination with elevated CO2, climate extreme elicited larger increases in fructan and sucrose content in the grasses without affecting the total carbohydrate content, while it significantly increased total carbohydrates in legumes. The accumulation of carbohydrates in legumes was accompanied by higher activity of sucrose phosphate synthase, sucrose synthase and ADP-Glc pyrophosphorylase. In the legumes, elevated CO2 in combination with climate extreme reduced protein, phosphorus (P and magnesium (Mg contents and the total element:N ratio and it increased phenol, lignin, tannin, carbon (C, nitrogen (N contents and C:N, C:P and N:P ratios. On the other hand, the tissue composition of the fructan accumulating grasses was not affected at this level, in line with recent views that fructans contribute to cellular homeostasis under stress. It is speculated that quality losses will

Climate Extreme Effects on the Chemical Composition of Temperate Grassland Species under Ambient and Elevated CO2: A Comparison of Fructan and Non-Fructan Accumulators

Science.gov (United States)

Zinta, Gaurav; Van den Ende, Wim; Janssens, Ivan A.; Asard, Han

2014-01-01

Elevated CO2 concentrations and extreme climate events, are two increasing components of the ongoing global climatic change factors, may alter plant chemical composition and thereby their economic and ecological characteristics, e.g. nutritional quality and decomposition rates. To investigate the impact of climate extremes on tissue quality, four temperate grassland species: the fructan accumulating grasses Lolium perenne, Poa pratensis, and the nitrogen (N) fixing legumes Medicago lupulina and Lotus corniculatus were subjected to water deficit at elevated temperature (+3°C), under ambient CO2 (392 ppm) and elevated CO2 (620 ppm). As a general observation, the effects of the climate extreme were larger and more ubiquitous in combination with elevated CO2. The imposed climate extreme increased non-structural carbohydrate and phenolics in all species, whereas it increased lignin in legumes and decreased tannins in grasses. However, there was no significant effect of climate extreme on structural carbohydrates, proteins, lipids and mineral contents and stoichiometric ratios. In combination with elevated CO2, climate extreme elicited larger increases in fructan and sucrose content in the grasses without affecting the total carbohydrate content, while it significantly increased total carbohydrates in legumes. The accumulation of carbohydrates in legumes was accompanied by higher activity of sucrose phosphate synthase, sucrose synthase and ADP-Glc pyrophosphorylase. In the legumes, elevated CO2 in combination with climate extreme reduced protein, phosphorus (P) and magnesium (Mg) contents and the total element:N ratio and it increased phenol, lignin, tannin, carbon (C), nitrogen (N) contents and C:N, C:P and N:P ratios. On the other hand, the tissue composition of the fructan accumulating grasses was not affected at this level, in line with recent views that fructans contribute to cellular homeostasis under stress. It is speculated that quality losses will be less

PENGARUH VARIASI SUHU PADA PROSES SELF TEMPERING DAN VARIASI WAKTU TAHAN PADA PROSES TEMPERING TERHADAP SIFAT MEKANIS BAJA AISI 4140

Directory of Open Access Journals (Sweden)

Sunardi Sunardi

2016-07-01

Full Text Available Tujuan penelitian ini adalah untuk mengetahui sifat mekanis pada baja AISI 4140 dengan proses tempering dengan variasi waktu tahan dan variasi suhu pada proses self tempering. Material terlebih dahulu dipanaskan pada suhu 850°C, di tahan dengan waktu 14 dan 28 menit, media pendinginan adalah Oli SAE 20. Pada proses tempering baja dipanaskan kembali dengan suhu 200°C di tahan dengan waktu 30 dan 120 menit. Sedangkan untuk proses self tempering, baja di panaskan pada suhu 850°C di tahan dengan waktu 14 dan 28 menit kemudian didinginkan, suhu yang harus dicapai pada pendinginan adalah 200°C, 400°C dan 600°C. Proses tempering dengan variasi waktu tahan mempunyai nilai kekerasan terbesar 50,1 HRC dengan waktu tahan 120 menit, sedangkan nilai kekerasan terbesar pada proses self tempering dengan variasi suhu adalah 29,68 HRC pada suhu 200°C. Nilai ketangguhan terbesar pada saat proses tempering adalah 0,341 (J/mm2 dengan waktu tahan 120 menit, sedangkan pada saat proses self tempering ketangguhan terbesar pada suhu 600°C dengan nilai 0,375 (J/mm2. Laju korosi terbesar pada saat tempering adalah 0,055 (mpy dengan waktu tahan 30 menit, sedangkan pada saat proses self tempering laju korosi terbesar pada suhu 400°C dengan nilai 0,0388 (mpy. 

Assessing Shifts of Mediterranean and Arid Climates Under RCP4.5 and RCP8.5 Climate Projections in Europe

Science.gov (United States)

Barredo, José I.; Mauri, Achille; Caudullo, Giovanni; Dosio, Alessandro

2018-04-01

The Mediterranean basin is the richest biodiversity region in Europe and a global hotspot of biological diversity. In spite of that, anthropogenic climate change is one of the most serious concerns for nature conservation in this region. One of the climatic threats is represented by shifts of the Mediterranean climate and expansion of the arid climate. In this paper, we present an assessment of changes in the spatial range of the Mediterranean climate in Europe and the conversion into arid climate under different greenhouse gas forcings, namely RCP4.5 and RCP8.5. We used 11 simulations in two future 30-year periods of state-of-the-art regional climate models from EURO-CORDEX. Our results indicate that by the end of the century under RCP8.5 the present Mediterranean climate zone is projected to contract by 16%, i.e. an area ( 157,000 km2) equivalent to half the size of Italy. This compares with the less severe scenario RCP4.5 that projected only a 3% reduction. In addition, the Mediterranean climate zone is projected to expand to other zones by an area equivalent to 24 and 50% of its present extent under RCP4.5 and RCP8.5, respectively. Our study indicates that expansion of the arid zone is almost always the cause for contraction of the Mediterranean zone. Under RCP8.5 the arid zone is projected to increase by more than twice its present extent, equivalent to three times the size of Greece. Results of this study are useful for identifying (1) priority zones for biodiversity conservation, i.e. stable Mediterranean climate zones, (2) zones requiring assisted adaptation, such as establishment of new protected areas, implementation of buffer zones around protected areas and creating ecological corridors connecting stable Mediterranean zones.

Hardness of H13 Tool Steel After Non-isothermal Tempering

Science.gov (United States)

Nelson, E.; Kohli, A.; Poirier, D. R.

2018-04-01

A direct method to calculate the tempering response of a tool steel (H13) that exhibits secondary hardening is presented. Based on the traditional method of presenting tempering response in terms of isothermal tempering, we show that the tempering response for a steel undergoing a non-isothermal tempering schedule can be predicted. Experiments comprised (1) isothermal tempering, (2) non-isothermal tempering pertaining to a relatively slow heating to process-temperature and (3) fast-heating cycles that are relevant to tempering by induction heating. After establishing the tempering response of the steel under simple isothermal conditions, the tempering response can be applied to non-isothermal tempering by using a numerical method to calculate the tempering parameter. Calculated results are verified by the experiments.

Climatic controls on diffuse groundwater recharge across Australia

Directory of Open Access Journals (Sweden)

O. V. Barron

2012-12-01

Full Text Available Reviews of field studies of groundwater recharge have attempted to investigate how climate characteristics control recharge, but due to a lack of data have not been able to draw any strong conclusions beyond that rainfall is the major determinant. This study has used numerical modelling for a range of Köppen-Geiger climate types (tropical, arid and temperate to investigate the effect of climate variables on recharge for different soil and vegetation types. For the majority of climate types, the correlation between the modelled recharge and total annual rainfall is weaker than the correlation between recharge and the annual rainfall parameters reflecting rainfall intensity. Under similar soil and vegetation conditions for the same annual rainfall, annual recharge in regions with winter-dominated rainfall is greater than in regions with summer-dominated rainfall. The importance of climate parameters other than rainfall in recharge estimation is highest in the tropical climate type. Mean annual values of solar radiation and vapour pressure deficit show a greater importance in recharge estimation than mean annual values of the daily mean temperature. Climate parameters have the lowest relative importance in recharge estimation in the arid climate type (with cold winters and the temperate climate type. For 75% of all soil, vegetation and climate types investigated, recharge elasticity varies between 2 and 4 indicating a 20% to 40% change in recharge for a 10% change in annual rainfall. Understanding how climate controls recharge under the observed historical climate allows more informed choices of analogue sites if they are to be used for climate change impact assessments.

Chronology of soil evolution and climatic changes in the dry steppe zone of the Northern Caucasus, Russia, during the 3rd millennium BC

NARCIS (Netherlands)

Alexandrovskiy, AL; van der Plicht, J; Belinskiy, AB; Khokhlova, OS

2001-01-01

Chrono-sequences of paleosols buried under different mounds of the large Ipatovo Kurgan, constructed during the Bronze Age, have been studied to reconstruct climatic changes in the dry steppe zone of the Northern Caucasus, Russia. Abrupt climatic and environmental changes in the third millennium BC

The potential distribution of bioenergy crops in Europe under present and future climate

International Nuclear Information System (INIS)

Tuck, Gill; Glendining, Margaret J.; Smith, Pete; Wattenbach, Martin; House, Jo I.

2006-01-01

We have derived maps of the potential distribution of 26 promising bioenergy crops in Europe, based on simple rules for suitable climatic conditions and elevation. Crops suitable for temperate and Mediterranean climates were selected from four groups: oilseeds (e.g. oilseed rape, sunflower), starch crops (e.g. potatoes), cereals (e.g. barley) and solid biofuel crops (e.g. sorghum, Miscanthus). The impact of climate change under different scenarios and GCMs on the potential future distribution of these crops was determined, based on predicted future climatic conditions. Climate scenarios based on four IPCC SRES emission scenarios, A1FI, A2, B1 and B2, implemented by four global climate models, HadCM3, CSIRO2, PCM and CGCM2, were used. The potential distribution of temperate oilseeds, cereals, starch crops and solid biofuels is predicted to increase in northern Europe by the 2080s, due to increasing temperatures, and decrease in southern Europe (e.g. Spain, Portugal, southern France, Italy, and Greece) due to increased drought. Mediterranean oil and solid biofuel crops, currently restricted to southern Europe, are predicted to extend further north due to higher summer temperatures. Effects become more pronounced with time and are greatest under the A1FI scenario and for models predicting the greatest climate forcing. Different climate models produce different regional patterns. All models predict that bioenergy crop production in Spain is especially vulnerable to climate change, with many temperate crops predicted to decline dramatically by the 2080s. The choice of bioenergy crops in southern Europe will be severely reduced in future unless measures are taken to adapt to climate change. (author)

Tempered stable laws as random walk limits

OpenAIRE

Chakrabarty, Arijit; Meerschaert, Mark M.

2010-01-01

Stable laws can be tempered by modifying the L\\'evy measure to cool the probability of large jumps. Tempered stable laws retain their signature power law behavior at infinity, and infinite divisibility. This paper develops random walk models that converge to a tempered stable law under a triangular array scheme. Since tempered stable laws and processes are useful in statistical physics, these random walk models can provide a basic physical model for the underlying physical phenomena.

Shifts in climate suitability for wine production as a result of climate change in a temperate climate wine region of Romania

Science.gov (United States)

Irimia, Liviu Mihai; Patriche, Cristian Valeriu; Quenol, Hervé; Sfîcă, Lucian; Foss, Chris

2018-02-01

Climate change is causing important shifts in the suitability of regions for wine production. Fine scale mapping of these shifts helps us to understand the evolution of vineyard climates, and to find solutions through viticultural adaptation. The aim of this study is to identify and map the structural and spatial shifts that occurred in the climatic suitability for wine production of the Cotnari wine growing region (Romania) between 1961 and 2013. Discontinuities in trends of temperature were identified, and the averages and trends of 13 climatic parameters for the 1961 to 1980 and 1981 to 2013 time periods were analysed. Using the averages of these climatic parameters, climate suitability for wine production was calculated at a resolution of 30 m and mapped for each time period, and the changes analysed. The results indicate shifts in the area's historic climatic profile, due to an increase of heliothermal resources and precipitation constancy. The area's climate suitability for wine production was modified by the loss of climate suitability for white table wines, sparkling wines and wine for distillates; shifts in suitability to higher altitudes by about 67 m, and a 48.6% decrease in the area suitable for quality white wines; and the occurrence of suitable climates for red wines at lower altitudes. The study showed that climate suitability for wine production has a multi-level spatial structure, with classes requiring a cooler climate being located at a higher altitude than those requiring a warmer climate. Climate change has therefore resulted in the shift of climate suitability classes for wine production to higher altitudes.

Setting Goals for Urban Scale Climate Governance

Science.gov (United States)

Rosenthal, J. K.; Brunner, E.

2007-12-01

The impacts of climate change on temperate urban areas may include the increase in frequency and intensity of damaging extreme weather events, such as heat waves, hurricanes, heavy rainfall or drought, and coastal flooding and erosion, and potential adverse impacts on infrastructure, energy systems, and public health. Warmer average summertime temperatures are also associated with environmental and public health liabilities, such as decreased air quality and increased peak electrical demand. Simultaneously, a strong global trend towards urbanization of poverty exists, with increased challenges for local governments to protect and sustain the well-being of growing cities and populations currently stressed by poverty, health and economic inequities. In the context of these trends, research at the city scale has sought to understand the social and economic impacts of climate change and variability and to evaluate strategies in the built environment that might serve as adaptive and mitigative responses to climate change. We review the goals and outcomes of several municipal climate protection programs, generally categorized as approaches based on technological innovation (e.g., new materials); changes in behavior and public education (e.g., neighborhood watch programs and cooling centers); improvements in urban design (e.g., zoning for mixed land-use; the use of water, vegetation and plazas to reduce the urban heat island effect); and efforts to incentivize the use of non-fossil-fuel based energy sources. Urban initiatives in European and American cities are assessed within the context of the global collective efforts enacted by the Kyoto Protocol and United Nations Framework Convention on Climate Change. Our concern is to understand the active networked role of urban managers in climate policies and programs in relation to supranational objectives and non-state actors.

Cloud attenuation studies of the six major climatic zones of Africa for Ka and V satellite system design

Directory of Open Access Journals (Sweden)

Temidayo Victor Omotosho

2014-01-01

Full Text Available Normal 0 false false false EN-GB X-NONE X-NONE Cloud cover statistics, cloud base and top height, cloud temperature, frequency of precipitation, freezing height, total cloud liquid water content (TCLWC and cloud attenuation data have been obtained for the six major climatic zones of Africa. The present results reveal a strong positive correlation between the monthly distribution of low cloud cover, cloud top height, cloud temperature, and frequency of precipitation in the six zones. The cumulative distribution of the TCLWC derived from radiosonde measurement in each climatic zone shows a departure from the TCLWC recommended by the ITU Study Group 3 data, with an exceedance percentage difference of 32% to 90% occurring 0.01% to 10% of the time. The underestimation of the TCLWC is greatest in the tropical rain forest. A comparison of the cloud attenuation cumulative distribution in the Ka and V bands reveals that the International Telecommunication Union – Region (ITU-R is an intergovernmental organization that develops rain model based on collected data around the world. This model underestimates the cloud attenuation in all of the six climatic zones by 2.0 dB and 4.7 dB for the arid Sahara desert, 1.3 dB and 3.0 dB in semi-arid North Africa, 1.3 dB and 1.5 dB in savannah North Africa, 2.0 dB and 3.6 dB in the tropical rain forest, 1.3 dB and 2.9 dB in savannah South Africa and 0.9 dB and 2.6 dB in semi-arid South Africa, respectively, at 30 and 50 GHz. Overall, the cloud attenuation in the tropical rain-forest zone is very high because of the high annual total cloud cover (98%, high annual frequency of precipitation (4.5, low annual clear sky amount (8%, high cloud depth (10,937 m, high 0°C isotherm height (4.7 km, high TCLWC (4.0 kg/m2 at 0.01% and low seasonal cloud base height (356 m.

Climate-Related Local Extinctions Are Already Widespread among Plant and Animal Species.

Directory of Open Access Journals (Sweden)

John J Wiens

2016-12-01

Full Text Available Current climate change may be a major threat to global biodiversity, but the extent of species loss will depend on the details of how species respond to changing climates. For example, if most species can undergo rapid change in their climatic niches, then extinctions may be limited. Numerous studies have now documented shifts in the geographic ranges of species that were inferred to be related to climate change, especially shifts towards higher mean elevations and latitudes. Many of these studies contain valuable data on extinctions of local populations that have not yet been thoroughly explored. Specifically, overall range shifts can include range contractions at the "warm edges" of species' ranges (i.e., lower latitudes and elevations, contractions which occur through local extinctions. Here, data on climate-related range shifts were used to test the frequency of local extinctions related to recent climate change. The results show that climate-related local extinctions have already occurred in hundreds of species, including 47% of the 976 species surveyed. This frequency of local extinctions was broadly similar across climatic zones, clades, and habitats but was significantly higher in tropical species than in temperate species (55% versus 39%, in animals than in plants (50% versus 39%, and in freshwater habitats relative to terrestrial and marine habitats (74% versus 46% versus 51%. Overall, these results suggest that local extinctions related to climate change are already widespread, even though levels of climate change so far are modest relative to those predicted in the next 100 years. These extinctions will presumably become much more prevalent as global warming increases further by roughly 2-fold to 5-fold over the coming decades.

Influence of neighbourhood information on 'Local Climate Zone' mapping in heterogeneous cities

Science.gov (United States)

Verdonck, Marie-Leen; Okujeni, Akpona; van der Linden, Sebastian; Demuzere, Matthias; De Wulf, Robert; Van Coillie, Frieke

2017-10-01

Local climate zone (LCZ) mapping is an emerging field in urban climate research. LCZs potentially provide an objective framework to assess urban form and function worldwide. The scheme is currently being used to globally map LCZs as a part of the World Urban Database and Access Portal Tools (WUDAPT) initiative. So far, most of the LCZ maps lack proper quantitative assessment, challenging the generic character of the WUDAPT workflow. Using the standard method introduced by the WUDAPT community difficulties arose concerning the built zones due to high levels of heterogeneity. To overcome this problem a contextual classifier is adopted in the mapping process. This paper quantitatively assesses the influence of neighbourhood information on the LCZ mapping result of three cities in Belgium: Antwerp, Brussels and Ghent. Overall accuracies for the maps were respectively 85.7 ± 0.5, 79.6 ± 0.9, 90.2 ± 0.4%. The approach presented here results in overall accuracies of 93.6 ± 0.2, 92.6 ± 0.3 and 95.6 ± 0.3% for Antwerp, Brussels and Ghent. The results thus indicate a positive influence of neighbourhood information for all study areas with an increase in overall accuracies of 7.9, 13.0 and 5.4%. This paper reaches two main conclusions. Firstly, evidence was introduced on the relevance of a quantitative accuracy assessment in LCZ mapping, showing that the accuracies reported in previous papers are not easily achieved. Secondly, the method presented in this paper proves to be highly effective in Belgian cities, and given its open character shows promise for application in other heterogeneous cities worldwide.

Long-term variability in the water budget and its controls in an oak-dominated temperate forest

Science.gov (United States)

Jing Xie; Ge Sun; Hou-Sen Chu; Junguo Liu; Steven G. McNulty; Asko Noormets; Ranjeet John; Zutao Ouyang; Tianshan Zha; Haitao Li; Wenbin Guan; Jiquan Chen

2014-01-01

Water availability is one of the key environmental factors that control ecosystem functions in temperate forests. Changing climate is likely to alter the ecohydrology and other ecosystem processes, which affect forest structures and functions. We constructed a multi-year water budget (2004–2010) and quantified environmental controls on an evapotranspiration (ET) in a...

Impacts of cloud immersion on microclimate, photosynthesis and water relations of fraser fir in a temperate mountain cloud forest

Science.gov (United States)

Keith Reinhardt; William K. Smith

2010-01-01

The red spruce-Fraser fir ecosystem (Picea rubens Sarg.-Abies fraseri [Pursh] Poir.) of the southern Appalachian mountains is a temperate zone cloud forest immersed in clouds for 30 to 40 percent of a typical summer day, and experiencing immersion on about 65 percent of all days annually. We compared the microclimate,...

The First Atmospheric Characterization of a Habitable-Zone Exoplanet

Science.gov (United States)

Stevenson, Kevin; Bean, Jacob; Charbonneau, David; Desert, Jean-Michel; Fortney, Jonathan; Irwin, Jonathan; Kreidberg, Laura; Line, Michael; Montet, Ben; Morley, Caroline

2015-10-01

Exoplanet surveys have recently revealed nearby planets orbiting within stellar habitable zones. This highly-anticipated breakthrough brings us one step closer in our quest to identify cosmic biosignatures, the indicators of extrasolar life. To achieve our goal, we must first study the atmospheres of these temperate worlds to measure their compositions and determine the prevalence of obscuring clouds. Using observations from the K2 mission, Co-I Montet recently announced the discovery of a 2.2 Earth-radii planet within the habitable zone of its relatively bright, nearby M dwarf parent star, K2-18. This temperate world is currently the best habitable-zone target for atmospheric characterization. Congruent with currently planned HST observations, we propose a Spitzer program to measure the transmission spectrum of the first habitable-zone exoplanet. Both telescopes are essential to revealing K2-18b's chemical composition. In a cloud-free, hydrogen-dominated atmosphere, the precision achieved by these measurements will be sufficient to detect methane, ammonia, and water vapor, which are the dominant C, N, and O bearing species at these temperatures. In turn, elemental abundance constraints from a primordial atmosphere can tell us about the composition of a protoplanetary disk in which Earth-like planets could have formed. Conversely, if the atmosphere contains thick clouds then the multi-wavelength observations from K2, HST, and Spitzer will constrain the clouds' properties. Because temperature plays a key role in the formation of clouds, their detection within the atmosphere of this habitable-zone exoplanet would be an important signpost that serves as a guide to future investigations of smaller, rocky exoplanets. As K2 continues discovering more habitable-zone planets, it is imperative that we perform spectral reconnaissance with Spitzer to determine their physical characteristics and begin understanding the prevalence of potentially-obscuring clouds prior to the

Climatic ecology of charismatic leadership ideals

NARCIS (Netherlands)

van de Vliert, Evert

2006-01-01

On the basis of the ecological leadership theory (van de Vliert & Smith, 2004), the perceived effectiveness of charismatic leadership in a country's organizations is conceptualized as an adaptation to two interacting characteristics of the environment-cold, temperate, or hot climate, and national

Solar radiation modelling using ANNs for different climates in China

International Nuclear Information System (INIS)

Lam, Joseph C.; Wan, Kevin K.W.; Yang, Liu

2008-01-01

Artificial neural networks (ANNs) were used to develop prediction models for daily global solar radiation using measured sunshine duration for 40 cities covering nine major thermal climatic zones and sub-zones in China. Coefficients of determination (R 2 ) for all the 40 cities and nine climatic zones/sub-zones are 0.82 or higher, indicating reasonably strong correlation between daily solar radiation and the corresponding sunshine hours. Mean bias error (MBE) varies from -3.3 MJ/m 2 in Ruoqiang (cold climates) to 2.19 MJ/m 2 in Anyang (cold climates). Root mean square error (RMSE) ranges from 1.4 MJ/m 2 in Altay (severe cold climates) to 4.01 MJ/m 2 in Ruoqiang. The three principal statistics (i.e., R 2 , MBE and RMSE) of the climatic zone/sub-zone ANN models are very close to the corresponding zone/sub-zone averages of the individual city ANN models, suggesting that climatic zone ANN models could be used to estimate global solar radiation for locations within the respective zones/sub-zones where only measured sunshine duration data are available. (author)

The effectiveness of common thermo-regulatory behaviours in a cool temperate grasshopper.

Science.gov (United States)

Harris, Rebecca M B; McQuillan, Peter; Hughes, Lesley

2015-08-01

Behavioural thermoregulation has the potential to alleviate the short-term impacts of climate change on some small ectotherms, without the need for changes to species distributions or genetic adaptation. We illustrate this by measuring the effect of behaviour in a cool temperate species of grasshopper (Phaulacridium vittatum) over a range of spatial and temporal scales in laboratory and natural field experiments. Microhabitat selection at the site scale was tested in free-ranging grasshoppers and related to changing thermal quality over a daily period. Artificial warming experiments were then used to measure the temperature at which common thermoregulatory behaviours are initiated and the subsequent reductions in body temperature. Behavioural means such as timing of activity, choice of substrates with optimum surface temperatures, shade seeking and postural adjustments (e.g. stilting, vertical orientation) were found to be highly effective at maintaining preferred body temperature. The maximum voluntarily tolerated temperature (MVT) was determined to be 44°C±0.4°C, indicating the upper bounds of thermal flexibility in this species. Behavioural thermoregulation effectively enables small ectotherms to regulate exposure to changing environmental temperatures and utilize the spatially and temporally heterogeneous environments they occupy. Species such as the wingless grasshopper, although adapted to cool temperate conditions, are likely to be well equipped to respond successfully to coarse scale climate change. Copyright © 2015 Elsevier Ltd. All rights reserved.

Developing climatic scenarios for pesticide fate modelling in Europe

International Nuclear Information System (INIS)

Blenkinsop, S.; Fowler, H.J.; Dubus, I.G.; Nolan, B.T.; Hollis, J.M.

2008-01-01

A climatic classification for Europe suitable for pesticide fate modelling was constructed using a 3-stage process involving the identification of key climatic variables, the extraction of the dominant modes of spatial variability in those variables and the use of k-means clustering to identify regions with similar climates. The procedure identified 16 coherent zones that reflect the variability of climate across Europe whilst maintaining a manageable number of zones for subsequent modelling studies. An analysis of basic climatic parameters for each zone demonstrates the success of the scheme in identifying distinct climatic regions. Objective criteria were used to identify one representative 26-year daily meteorological series from a European dataset for each zone. The representativeness of each series was then verified against the zonal classifications. These new FOOTPRINT climate zones provide a state-of-the-art objective classification of European climate complete with representative daily data that are suitable for use in pesticide fate modelling. - The FOOTPRINT climatic zones provide an objective climatic classification and daily climate series that may be used for the modelling of pesticide fate across Europe

Functional and phylogenetic relatedness in temporary wetland invertebrates: current macroecological patterns and implications for future climatic change scenarios.

Science.gov (United States)

Ruhí, Albert; Boix, Dani; Gascón, Stéphanie; Sala, Jordi; Batzer, Darold P

2013-01-01

In freshwater ecosystems, species compositions are known to be determined hierarchically by large to small‑scale environmental factors, based on the biological traits of the organisms. However, in ephemeral habitats this heuristic framework remains largely untested. Although temporary wetland faunas are constrained by a local filter (i.e., desiccation), we propose its magnitude may still depend on large-scale climate characteristics. If this is true, climate should be related to the degree of functional and taxonomic relatedness of invertebrate communities inhabiting seasonal wetlands. We tested this hypothesis in two ways. First, based on 52 biological traits for invertebrates, we conducted a case study to explore functional trends among temperate seasonal wetlands differing in the harshness (i.e., dryness) of their dry season. After finding evidence of trait filtering, we addressed whether it could be generalized across a broader climatic scale. To this end, a meta-analysis (225 seasonal wetlands spread across broad climatic categories: Arid, Temperate, and Cold) allowed us to identify whether an equivalent climate-dependent pattern of trait richness was consistent between the Nearctic and the Western Palearctic. Functional overlap of invertebrates increased from mild (i.e., Temperate) to harsher climates (i.e., Arid and Cold), and phylogenetic clustering (using taxonomy as a surrogate) was highest in Arid and lowest in Temperate wetlands. We show that, (i) as has been described in streams, higher relatedness than would be expected by chance is generally observed in seasonal wetland invertebrate communities; and (ii) this relatedness is not constant but climate-dependent, with the climate under which a given seasonal wetland is located determining the functional overlap and the phylogenetic clustering of the community. Finally, using a space-for-time substitution approach we suggest our results may anticipate how the invertebrate biodiversity embedded in these

Soil respiration and organic carbon dynamics with grassland conversions to woodlands in temperate china.

Directory of Open Access Journals (Sweden)

Wei Wang

Full Text Available Soils are the largest terrestrial carbon store and soil respiration is the second-largest flux in ecosystem carbon cycling. Across China's temperate region, climatic changes and human activities have frequently caused the transformation of grasslands to woodlands. However, the effect of this transition on soil respiration and soil organic carbon (SOC dynamics remains uncertain in this area. In this study, we measured in situ soil respiration and SOC storage over a two-year period (Jan. 2007-Dec. 2008 from five characteristic vegetation types in a forest-steppe ecotone of temperate China, including grassland (GR, shrubland (SH, as well as in evergreen coniferous (EC, deciduous coniferous (DC and deciduous broadleaved forest (DB, to evaluate the changes of soil respiration and SOC storage with grassland conversions to diverse types of woodlands. Annual soil respiration increased by 3%, 6%, 14%, and 22% after the conversion from GR to EC, SH, DC, and DB, respectively. The variation in soil respiration among different vegetation types could be well explained by SOC and soil total nitrogen content. Despite higher soil respiration in woodlands, SOC storage and residence time increased in the upper 20 cm of soil. Our results suggest that the differences in soil environmental conditions, especially soil substrate availability, influenced the level of annual soil respiration produced by different vegetation types. Moreover, shifts from grassland to woody plant dominance resulted in increased SOC storage. Given the widespread increase in woody plant abundance caused by climate change and large-scale afforestation programs, the soils are expected to accumulate and store increased amounts of organic carbon in temperate areas of China.

Emergent Toxins in North Atlantic Temperate Waters: A Challenge for Monitoring Programs and Legislation

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Marisa Silva

2015-03-01

Full Text Available Harmful Algal Blooms (HAB are complex to manage due to their intermittent nature and their severe impact on the economy and human health. The conditions which promote HAB have not yet been fully explained, though climate change and anthropogenic intervention are pointed as significant factors. The rise of water temperature, the opening of new sea canals and the introduction of ship ballast waters all contribute to the dispersion and establishment of toxin-producing invasive species that promote the settling of emergent toxins in the food-chain. Tetrodotoxin, ciguatoxin, palytoxin and cyclic imines are commonly reported in warm waters but have also caused poisoning incidents in temperate zones. There is evidence that monitoring for these toxins exclusively in bivalves is simplistic and underestimates the risk to public health, since new vectors have been reported for these toxins and as well for regulated toxins such as PSTs and DSTs. In order to avoid public health impacts, there is a need for adequate monitoring programs, a need for establishing appropriate legislation, and a need for optimizing effective methods of analysis. In this review, we will compile evidence concerning emergent marine toxins and provide data that may indicate the need to restructure the current monitoring programs of HAB.

Emergent Toxins in North Atlantic Temperate Waters: A Challenge for Monitoring Programs and Legislation

Science.gov (United States)

Silva, Marisa; Pratheepa, Vijaya K.; Botana, Luis M.; Vasconcelos, Vitor

2015-01-01

Harmful Algal Blooms (HAB) are complex to manage due to their intermittent nature and their severe impact on the economy and human health. The conditions which promote HAB have not yet been fully explained, though climate change and anthropogenic intervention are pointed as significant factors. The rise of water temperature, the opening of new sea canals and the introduction of ship ballast waters all contribute to the dispersion and establishment of toxin-producing invasive species that promote the settling of emergent toxins in the food-chain. Tetrodotoxin, ciguatoxin, palytoxin and cyclic imines are commonly reported in warm waters but have also caused poisoning incidents in temperate zones. There is evidence that monitoring for these toxins exclusively in bivalves is simplistic and underestimates the risk to public health, since new vectors have been reported for these toxins and as well for regulated toxins such as PSTs and DSTs. In order to avoid public health impacts, there is a need for adequate monitoring programs, a need for establishing appropriate legislation, and a need for optimizing effective methods of analysis. In this review, we will compile evidence concerning emergent marine toxins and provide data that may indicate the need to restructure the current monitoring programs of HAB. PMID:25785464

Settlement determination of operating moisture of autoclaved aerated concrete in different climatic zones

Directory of Open Access Journals (Sweden)

Pastushkov Pavel Pavlovich

Full Text Available In the process of operation of buildings the moisture state of enveloping structures materials is changing depending on their construction features, properties of the material, temperature and moisture conditions in the premises, climatic conditions of the construction area. Moisture mode determines the operational properties of the enveloping structures of a building. It directly influences the thermal characteristics of enveloping structure and energy efficiency of the applied materials. The analysis of the methods for calculation of moisture behavior of enclosing structures is carried out. The research relevance of operational moisture of AAC is substantiated. Experimental studies and results of the sorption moisturizing and water vapor permeability of leading marks of aerated concrete are carried out. The authors offer the results of numerical calculations of the moisture behavior of aerated concrete in the walls with mark D400 with facade thermal insulation composite systems - with external plaster layers for different climatic zones of construction.

Impacts of Severe Weather, Climate Zone, and Energy Factors on Base Realignment and Closure (BRAC)

Science.gov (United States)

2015-03-26

Partial Fulfillment of the Requirements for the Degree of Master of Science in Engineering Management Christopher L. Teke, Major, USAF Major...the science behind severe weather occurrences and climate zone. Chapter 3 further details the methodology used in the analysis and sets the stage... actuarial estimates and should be thought of as insurance premiums, and ought to remain a budgeted cost if a base stays open. In contrast, if a base is

Cave visitation by temperate zone bats: effects of climatic factors

Czech Academy of Sciences Publication Activity Database

Berková, Hana; Zukal, Jan

2010-01-01

Roč. 280, č. 4 (2010), s. 387-395 ISSN 0952-8369 R&D Projects: GA ČR GA206/01/1555; GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60930519 Keywords : automatic registration * bats * flight activity * hibernaculum * seasonal changes Subject RIV: EG - Zoology Impact factor: 1.787, year: 2010

Effects of elevated atmospheric CO2, prolonged summer drought and temperature increase on N2O and CH4 fluxes in a temperate heathland

DEFF Research Database (Denmark)

Carter, Mette Sustmann; Ambus, Per; Albert, Kristian Rost

2011-01-01

In temperate regions, climate change is predicted to increase annual mean temperature and intensify the duration and frequency of summer droughts, which together with elevated atmospheric carbon dioxide (CO2) concentrations, may affect the exchange of nitrous oxide (N2O) and methane (CH4) between...... terrestrial ecosystems and the atmosphere. We report results from the CLIMAITE experiment, where the effects of these three climate change parameters were investigated solely and in all combinations in a temperate heathland. Field measurements of N2O and CH4 fluxes took place 1–2 years after the climate...... change manipulations were initiated. The soil was generally a net sink for atmospheric CH4. Elevated temperature (T) increased the CH4 uptake by on average 10 μg C m−2 h−1, corresponding to a rise in the uptake rate of about 20%. However, during winter elevated CO2 (CO2) reduced the CH4 uptake, which...

Modelled spatiotemporal variability of outdoor thermal comfort in local climate zones of the city of Brno, Czech Republic

Czech Academy of Sciences Publication Activity Database

Geletič, Jan; Lehnert, M.; Savić, S.; Milošević, D.

2018-01-01

Roč. 624, 15 May (2018), s. 385-395 ISSN 0048-9697 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67985807 Keywords : HUMIDEX * MUKLIMO_3 * air temperature * relative humidity * local climate zones * heat wave Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 4.900, year: 2016

Spatial variation in the storages and age-related dynamics of forest carbon sequestration in different climate zones-evidence from black locust plantations on the Loess Plateau of China.

Science.gov (United States)

Li, Taijun; Ren, Bowen; Wang, Dahui; Liu, Guobin

2015-01-01

Knowledge about the long-term influences of climate change on the amount of potential carbon (C) sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L.) in the semi-arid and semi-humid zones of China's Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha-1. Soil organic C (SOC) increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010). However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y). The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011), yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha-1 to 28.4 Mg C ha-1 during the old forest stage (38 to 56 y). The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y), the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration.

Climate evolution on the terrestrial planets

International Nuclear Information System (INIS)

Kasting, J.F.; Toon, O.B.

1989-01-01

The present comparative evaluation of the long-term evolution of the Venus, earth, and Mars climates suggests that the earth's climate has remained temperate over most of its history despite a secular solar luminosity increase in virtue of a negative-feedback cycle based on atmospheric CO 2 levels and climate. The examination of planetary climate histories suggests that an earth-sized planet should be able to maintain liquid water on its surface at orbital distances in the 0.9-1.5 AU range, comparable to the orbit of Mars; this, in turn, implies that there may be many other habitable planets within the Galaxy

Structural and functional responses of plant communities to climate change-mediated alterations in the hydrology of riparian areas in temperate Europe.

Science.gov (United States)

Baattrup-Pedersen, Annette; Garssen, Annemarie; Göthe, Emma; Hoffmann, Carl Christian; Oddershede, Andrea; Riis, Tenna; van Bodegom, Peter M; Larsen, Søren E; Soons, Merel

2018-04-01

The hydrology of riparian areas changes rapidly these years because of climate change-mediated alterations in precipitation patterns. In this study, we used a large-scale in situ experimental approach to explore effects of drought and flooding on plant taxonomic diversity and functional trait composition in riparian areas in temperate Europe. We found significant effects of flooding and drought in all study areas, the effects being most pronounced under flooded conditions. In near-stream areas, taxonomic diversity initially declined in response to both drought and flooding (although not significantly so in all years) and remained stable under drought conditions, whereas the decline continued under flooded conditions. For most traits, we found clear indications that the functional diversity also declined under flooded conditions, particularly in near-stream areas, indicating that fewer strategies succeeded under flooded conditions. Consistent changes in community mean trait values were also identified, but fewer than expected. This can have several, not mutually exclusive, explanations. First, different adaptive strategies may coexist in a community. Second, intraspecific variability was not considered for any of the traits. For example, many species can elongate shoots and petioles that enable them to survive shallow, prolonged flooding but such abilities will not be captured when applying mean trait values. Third, we only followed the communities for 3 years. Flooding excludes species intolerant of the altered hydrology, whereas the establishment of new species relies on time-dependent processes, for instance the dispersal and establishment of species within the areas. We expect that altered precipitation patterns will have profound consequences for riparian vegetation in temperate Europe. Riparian areas will experience loss of taxonomic and functional diversity and, over time, possibly also alterations in community trait responses that may have cascading effects

Gas production analysis of a fixed-dome digester operated under temperate climates in central Ohio

Energy Technology Data Exchange (ETDEWEB)

Castano, J.; Martin, J.F.; Ciotola, R.; Schlea, D.; Eger, C. [Ohio State Univ., Columbus, OH (United States). Ecological Engineering Program

2010-07-01

Anaerobic digestion is not used in small farms in the United States because of the high costs and large size of existing digesters. More affordable digesters are needed to realize the environmental and energetic benefits on smaller farms in temperate climates. Field and laboratory experiments were conducted to determine the effects of seasonal temperature variation on gas production. Once a baseline for gas production and digester function is determined, then methods can be identified to increase gas production in these conditions. A 1 cubic metre modified fixed-dome digester was buried just below the soil surface at the Ohio State University dairy farm. The digester was fed with 1 kg/m{sup 3} per day of diluted cow manure. The kinetics associated with 6 specific anaerobic trophic groups at 5 and 15 degrees C were determined through laboratory experiments. The average ambient temperature from October through December 2009 was 7.2 degrees C, while the average digester temperature was 8.6 degrees C. The average specific gas production during this period was 0.01746 litres/Kg of volatile solids (VS). Preliminary results showed an average reduction of 44 per cent in VS and volatile fatty acids concentration of 8441 mg/litre inside the digester, from which 61 per cent, 26 per cent, 1 per cent, 7 per cent, and 5 per cent were acetic, propionic, isobutyric, isovaleric and valeric acids, respectively. These preliminary results suggest that the decreasing gas production is associated with a kinetic constraint for a specific trophic group.

Vulnerability of boreal zone for increased nitrogen loading due to climate change

Science.gov (United States)

Rankinen, Katri; Holmberg, Maria

2016-04-01

The observed rapid warming of the boreal zone that has been observed in Finland (0.14 °C by decade) is expected to continue (http://www.ipcc.ch/report/ar5/wg1/). Also precipitation is assumed to increase in future. These changes may increase nitrogen (N) loading from terrestrial environments to water bodies by accelerating soil organic matter decay and by increasing runoff. Nitrogen is limiting nutrient in the Baltic Sea but also in some lakes, so increased loading may increase eutrophication. Further, high nitrate levels in drinking water may cause methaemoglobin anemia for humans, and nitrate is also connected to increased risk of diabetes and cancer. Thus EU has set upper limits to nitrate concentration in drinking water. MONIMET (LIFE12 ENV/FI/000409) is a project about Climate Change Indicators and Vulnerability of Boreal Zone. We simulated N loading from two boreal catchments to the receiving waters by the dynamic, catchment scale model INCA in different climate change and land use change scenarios. We calculated land use specific N loading values for these two well monitored catchments that belong to the LTER (The Long Term Ecological Research) monitoring network. We upscaled the results to the larger river basin, combining them with the information on drinking water supply to assess the vulnerability. Specific emphasis was paid on nitrate concentrations in soil water and groundwater. In general, land use change has higher influence on N loading than increase in precipitation and temperature alone. Peak runoff will sift from snow melting peak in April to late autumn and winter. Growing season will become longer allowing more efficient vegetation uptake of nutrients. Small groundwater aquifers and private wells in the middle of agricultural fields will be in the risk of increased N concentrations, if agricultural N loading increases due to changes in agricultural patterns and land use change.

Monoterpene emissions in response to long-term night-time warming, elevated CO2 and extended summer drought in a temperate heath ecosystem

DEFF Research Database (Denmark)

Tiiva, Päivi; Tang, Jing; Michelsen, Anders

2017-01-01

Monoterpenes emitted from plants have an important role in atmospheric chemistry through changing atmospheric oxidative capacity, forming new particles and secondary organic aerosols. The emission rates and patterns can be affected by changing climate. In this study, emission responses to six years...... of climatic manipulations (elevated CO2, extended summer drought and night-time warming) were investigated in a temperate semi-natural heath ecosystem. Samples for monoterpene analysis were collected in seven campaigns during an entire growing season (April-November, 2011). The results showed...... that the temperate heath ecosystem was a considerable source of monoterpenes to the atmosphere, with the emission averaged over the 8month measurement period of 21.7±6.8μgm(-2)groundareah(-1) for the untreated heath. Altogether, 16 monoterpenes were detected, of which the most abundant were α-pinene, δ-3-carene...

Temper Tantrums

Science.gov (United States)

... Nine Steps to More Effective Parenting How Can Parents Discipline Without Spanking? Delayed Speech or Language Development Talking to Your Child's Preschool Teacher Your Child's Habits Separation Anxiety Breath-Holding Spells Train Your Temper View ...

Do colder and hotter climates make richer societies more, but poorer societies less, happy and altruistic?

NARCIS (Netherlands)

Van de Vliert, E; Huang, X; Parker, PM

Physiological needs for thermal comfort, nutritional comfort, and healthiness make colder and hotter climates more demanding than more temperate climates. Affluence may help to meet those thermal demands. Two country-level studies indeed show that thermal demands (colder and hotter climates) and

Monitoring the effects of climate and agriculture intensity on nutrient fluxes in lowland streams: a comparison between temperate Denmark and subtropical Uruguay

Science.gov (United States)

Goyenola, Guillermo; Meerhof, Mariane; Teixeira de Mello, Franco; González-Bergonzoni, Ivan; Graeber, Daniel; Vidal, Nicolas; Mazzeo, Nestor; Ovesen, Niels; Jeppesen, Erik; Thodsen, Hans; Kronvang, Brian

2014-05-01

Climate is changing towards more extreme conditions all over the world. At the same time, land use is becoming more intensive worldwide and particularly in many developing countries, whereas several developed countries are trying to reduce the impacts of intensive agricultural production and lower the excessive nutrient loading and eutrophication symptoms in water bodies. In 2009, we initiated a comparative research project between the subtropical region (Uruguay) and the temperate region (Denmark) to compare the hydrology and nutrient fluxes in paired micro-catchments with extensive production or intensive agriculture. The four selected streams drained catchments of similar size (7 to 19 km2). We have established similarly equipped monitoring stations in the four micro-catchments in spring (November 2009, Uruguay; March 2010, Denmark) to monitor the effects of land use and agriculture intensity on stream hydrology and nutrient concentrations and fluxes under different climate conditions. We have conducted high frequency measurements in the four lowland streams with underwater probes (turbidity, pH, conductivity and oxygen measured every 15 minutes), fortnight grab sampling of water and automatic sampling of composite water samples for nutrient analysis (total and dissolved nitrogen and phosphorus; sampled every four hours and accumulated fortnightly). Moreover, water level and meteorological information (precipitation, air temperature, global radiation, humidity) has been recorded every 10 minutes and instantaneous flow measurements have been conducted at regular intervals, to facilitate the calculation of instantaneous discharge from continuous records of water level (stage-discharge relationships). We will show results of ca. 2 years from this comparative study between Uruguay and Denmark, and the importance of differences in climate and land use will be discussed.

Effect of temperate climate tree species on gross ammonification, gross nitrification and N2O formation

Science.gov (United States)

Brüggemann, N.; Rosenkranz, P.; Papen, H.; Butterbach-Bahl, K.

2003-04-01

Microbial nitrogen turnover processes in the soil, like ammonification, nitrification and denitrification, play an important role in the formation of nitrous oxide (N2O): (i) ammonification, because it releases nitrogen from organic material in the form of ammonium (NH4+), which in turn can serve as substrate for nitrification; (ii) nitrification itself (i.e. the turnover of NH4+ to nitrate, NO3-), during which nitric oxide (NO) and N2O can be released as by-products at varying ratios; (iii) denitrification, in which NO3- serves as electron acceptor and is converted to molecular nitrogen (N2) via NO and N2O as intermediates, that can also be partially lost to the atmosphere. Temperate forest soils are a substantial source of atmospheric N2O contributing up to 10% to the total atmospheric N2O budget. However, this figure is afflicted with a huge uncertainty due to a number of factors governing the soil N2O formation, consumption, release and uptake, which are not fully understood at present. To one of these factors belongs the influence of the tree species on nitrogen turnover processes in the soil and the formation of N trace gases related with them. The aim of the present work was to analyse this tree species effect for the temperate climate region. For this purpose the effect of five different temperate tree species, having the same age and growing on the same soil in direct vicinity to each other, on gross ammonification and gross nitrification as well as on N2O formation was investigated. The trees (common beech, Fagus sylvatica; pedunculate oak, Quercus robur; Norway spruce, Picea abies; Japanese larch, Larix leptolepis; mountain pine, Pinus mugo) were part of a species trial in Western Jutland, Denmark, established in 1965 on a former sandy heathland. Samples from the soil under these five tree species were taken in spring and in summer 2002, respectively, differentiating between organic layer and mineral soil. The gross rates of ammonification as well of

Adapting to climate variability and change in Ontario : volume 4 of the Canada country study : climate impacts and adaptation

Energy Technology Data Exchange (ETDEWEB)

Smith, J.; Lavender, B. [Smith and Lavender Envrironmental Consultants, ON (Canada); Auld, H.; Broadhurst, D.; Bullock, T. [Environment Canada, Ottawa, ON (Canada). Ontario Region

1998-03-01

An assessment of how climate change will affect Ontario over the next century, including its social, biological and economic environment, is presented. The most significant impacts are expected to result from changes in precipitation patterns, in soil moisture, and in greater intensity and frequency of extreme weather events. Some of the major impacts of changing climate discussed in this volume include: (1) more pollution episodes, (2) increased heat stress, (3) lowering of average water levels of the Great Lakes, (4) changes in the hydrologic cycle which could result in variability of water supply for hydroelectric power production, (5) warming waters of the Great Lakes which could cause fish species to shift northward, (6) cool temperate, moderate temperate and grassland regions could expand northwards as the boreal forest retreats, (7) longer crop growing seasons, (8) decreased snow loads, and (9) reduced ice on the Great Lakes which would increase the length of the shipping season. The general conclusion is that adapting to changing climate will require a knowledge of how climate changes occur and how the changes are likely to affect the environment, society and economy. Changes in other key variables such as technology, personal preferences and social values will also influence the rate of climate change and Ontario`s ability to adapt to it. refs., tabs., figs.

Seasonal ovulatory activity exists in tropical Creole female goats and Black Belly ewes subjected to a temperate photoperiod.

Science.gov (United States)

Chemineau, Philippe; Daveau, Agnès; Cognié, Yves; Aumont, Gilles; Chesneau, Didier

2004-08-27

a simulated tropical photoperiod also showed seasonality in their ovulatory activity. Such results indicate that both species are capable of showing seasonality under the photoperiodic changes of the temperate zone even though they do not originate from these regions.

Dynamics of low-temperature acclimation in temperate and boreal conifer foliage in a mild winter climate

Science.gov (United States)

G. Richard Strimbeck; Trygve D. Kjellsen; Paul G. Schaberg; Paula F. Murakami

2008-01-01

To provide baseline data for physiological studies of extreme low-temperature (LT) tolerance in boreal conifers, we profiled LT stress responses, liquid nitrogen (LN2)-quench tolerance, and sugar concentrations in foliage of boreal-temperate species pairs in the genera Abies, Picea and Pinus, growing in an...

Increased drought impacts on temperate rainforests from southern South America: results of a process-based, dynamic forest model.

Directory of Open Access Journals (Sweden)

Alvaro G Gutiérrez

Full Text Available Increased droughts due to regional shifts in temperature and rainfall regimes are likely to affect forests in temperate regions in the coming decades. To assess their consequences for forest dynamics, we need predictive tools that couple hydrologic processes, soil moisture dynamics and plant productivity. Here, we developed and tested a dynamic forest model that predicts the hydrologic balance of North Patagonian rainforests on Chiloé Island, in temperate South America (42°S. The model incorporates the dynamic linkages between changing rainfall regimes, soil moisture and individual tree growth. Declining rainfall, as predicted for the study area, should mean up to 50% less summer rain by year 2100. We analysed forest responses to increased drought using the model proposed focusing on changes in evapotranspiration, soil moisture and forest structure (above-ground biomass and basal area. We compared the responses of a young stand (YS, ca. 60 years-old and an old-growth forest (OG, >500 years-old in the same area. Based on detailed field measurements of water fluxes, the model provides a reliable account of the hydrologic balance of these evergreen, broad-leaved rainforests. We found higher evapotranspiration in OG than YS under current climate. Increasing drought predicted for this century can reduce evapotranspiration by 15% in the OG compared to current values. Drier climate will alter forest structure, leading to decreases in above ground biomass by 27% of the current value in OG. The model presented here can be used to assess the potential impacts of climate change on forest hydrology and other threats of global change on future forests such as fragmentation, introduction of exotic tree species, and changes in fire regimes. Our study expands the applicability of forest dynamics models in remote and hitherto overlooked regions of the world, such as southern temperate rainforests.

Increased drought impacts on temperate rainforests from southern South America: results of a process-based, dynamic forest model.

Science.gov (United States)

Gutiérrez, Alvaro G; Armesto, Juan J; Díaz, M Francisca; Huth, Andreas

2014-01-01

Increased droughts due to regional shifts in temperature and rainfall regimes are likely to affect forests in temperate regions in the coming decades. To assess their consequences for forest dynamics, we need predictive tools that couple hydrologic processes, soil moisture dynamics and plant productivity. Here, we developed and tested a dynamic forest model that predicts the hydrologic balance of North Patagonian rainforests on Chiloé Island, in temperate South America (42°S). The model incorporates the dynamic linkages between changing rainfall regimes, soil moisture and individual tree growth. Declining rainfall, as predicted for the study area, should mean up to 50% less summer rain by year 2100. We analysed forest responses to increased drought using the model proposed focusing on changes in evapotranspiration, soil moisture and forest structure (above-ground biomass and basal area). We compared the responses of a young stand (YS, ca. 60 years-old) and an old-growth forest (OG, >500 years-old) in the same area. Based on detailed field measurements of water fluxes, the model provides a reliable account of the hydrologic balance of these evergreen, broad-leaved rainforests. We found higher evapotranspiration in OG than YS under current climate. Increasing drought predicted for this century can reduce evapotranspiration by 15% in the OG compared to current values. Drier climate will alter forest structure, leading to decreases in above ground biomass by 27% of the current value in OG. The model presented here can be used to assess the potential impacts of climate change on forest hydrology and other threats of global change on future forests such as fragmentation, introduction of exotic tree species, and changes in fire regimes. Our study expands the applicability of forest dynamics models in remote and hitherto overlooked regions of the world, such as southern temperate rainforests.

Adhesion and wear properties of boro-tempered ductile iron

International Nuclear Information System (INIS)

Kayali, Yusuf; Yalcin, Yilmaz; Taktak, Suekrue

2011-01-01

Highlights: → In this study, the wear and adhesion properties of BDI were investigated. → Boro-tempering process under several heat treatment conditions was examined. → Optical microscope, SEM and XRD analysis were carried out to investigate the microstructure. → It was observed that boro-tempering process improves micro-hardness and wear properties of ductile irons. -- Abstract: In this study, adhesion and wear properties of boro-tempered ductile iron (BDI) were investigated. Boro-tempering was carried out on two stage processes i.e. boronizing and tempering. At the first stage, ductile iron samples were boronized by using pack process at 900 o C for 1, 3, and 5 h and then, secondly tempered at 250, 300, 350, and 400 o C for 1 h. X-ray diffraction (XRD) analysis of boro-tempered samples showed that FeB and Fe 2 B phases were found on the surface of the samples. The Daimler-Benz Rockwell-C adhesion test was used to assess the adhesion of boride layer. Test result showed that adhesion decreased with increasing boriding time and increased with increasing tempering temperature. Dry sliding wear tests of these samples were performed against Al 2 O 3 ball at a constant sliding speed and loads of 5 and 10 N. Wear tests indicated that boro-tempering heat treatment increased wear resistance of ductile iron. In addition, it was found that while wear rate of boro-tempered samples decreased with increasing boriding time, there is no significant affect of tempering temperature on wear rate.

Effect of long term thermal ageing on the mechanical properties of ASTM A533B and A508 steels in the quenched and tempered and simulated heat affected zone conditions

Energy Technology Data Exchange (ETDEWEB)

Druce, S.G.; Gage, G.; Jordan, G.

1985-04-01

Manganese-molybdenum-nickel steels are used commonly in the fabrication of critical components in the PWR primary circuit operating at temperatures up to 345 C for periods up to several hundred thousand hours. Demonstration of structural integrity throughout service life requires quantification of the effects of thermal ageing on mechanical properties. Thermal ageing in the temperature range 300 to 550 C for durations up to 2000 h was studied in quenched and tempered A533B plate and simulated heat-affected-zone (HAZ) microstructures in A533B and A508 materials. A combination of tensile, hardness and Charpy impact tests were used to assess changes in rheological and toughness related properties. Quantitative fractography and Auger spectroscopy were used to characterize associated changes in fracture mode and grain boundary composition.

Study on tempering behaviour of AISI 410 stainless steel

International Nuclear Information System (INIS)

Chakraborty, Gopa; Das, C.R.; Albert, S.K.; Bhaduri, A.K.; Thomas Paul, V.; Panneerselvam, G.; Dasgupta, Arup

2015-01-01

Martensitic stainless steels find extensive applications due to their optimum combination of strength, hardness and wear-resistance in tempered condition. However, this class of steels is susceptible to embrittlement during tempering if it is carried out in a specific temperature range resulting in significant reduction in toughness. Embrittlement of as-normalised AISI 410 martensitic stainless steel, subjected to tempering treatment in the temperature range of 673–923 K was studied using Charpy impact tests followed by metallurgical investigations using field emission scanning electron and transmission electron microscopes. Carbides precipitated during tempering were extracted by electrochemical dissolution of the matrix and identified by X-ray diffraction. Studies indicated that temper embrittlement is highest when the steel is tempered at 823 K. Mostly iron rich carbides are present in the steel subjected to tempering at low temperatures of around 723 K, whereas chromium rich carbides (M 23 C 6 ) dominate precipitation at high temperature tempering. The range 773–823 K is the transition temperature range for the precipitates, with both Fe 2 C and M 23 C 6 types of carbides coexisting in the material. The nucleation of Fe 2 C within the martensite lath, during low temperature tempering, has a definite role in the embrittlement of this steel. Embrittlement is not observed at high temperature tempering because of precipitation of M 23 C 6 carbides, instead of Fe 2 C, preferentially along the lath and prior austenite boundaries. Segregation of S and P, which is widely reported as one of the causes for temper embrittlement, could not be detected in the material even through Auger electron spectroscopy studies. - Highlights: • Tempering behaviour of AISI 410 steel is studied within 673–923 K temperature range. • Temperature regime of maximum embrittlement is identified as 773–848 K. • Results show that type of carbide precipitation varies with

[Development of APSIM (agricultural production systems simulator) and its application].

Science.gov (United States)

Shen, Yuying; Nan, Zhibiao; Bellotti, Bill; Robertson, Michael; Chen, Wen; Shao, Xinqing

2002-08-01

Soil-crop simulator model is an effective tool for providing decision on agricultural management. APSIM (Agricultural Production Systems Simulator) was developed to simulate the biophysical process in farming system, and particularly in the economic and ecological features of the systems under climatic risk. The current literatures revealed that APSIM could be applied in wide zone, including temperate continental, temperate maritime, sub-tropic and arid climate, and Mediterranean climates, with the soil type of clay, duplex soil, vertisol, silt sandy, silt loam and silt clay loam. More than 20 crops have been simulated well. APSIM is powerful on describing crop structure, crop sequence, yield prediction, and quality control as well as erosion estimation under different planting pattern.

Long-term variability and environmental control of the carbon cycle in an oak-dominated temperate forest

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Jing Xie; Jiquan Chen; Ge Sun; Housen Chu; Asko Noormets; Zutao Ouyang; Ranjeet John; Shiqiang Wan; Wenbin Guan

2014-01-01

Our understanding of the long-term carbon (C) cycle of temperate deciduous forests and its sensitivity to climate variability is limited due to the large temporal dynamics of C fluxes. The goal of the study was to quantify the effects of environmental variables on the C balance in a 70-year-old mixed-oak woodland forest over a 7-year period in northwest Ohio, USA. The...

Antibiotic resistant Pseudomonas spp. in the aquatic environment: A prevalence study under tropical and temperate climate conditions.

Science.gov (United States)

Devarajan, Naresh; Köhler, Thilo; Sivalingam, Periyasamy; van Delden, Christian; Mulaji, Crispin K; Mpiana, Pius T; Ibelings, Bastiaan W; Poté, John

2017-05-15

by evaluating the aquatic ecosystems sediments from tropical and temperate climate conditions. Taken together, our findings demonstrate a widespread occurrence of antibiotic resistance in aquatic ecosystems sediments receiving untreated/treated wastewater and how these contemporary sources of contamination, contribute to the spread of microbial resistance in the aquatic environment. This research presents also useful tools to evaluate sediment quality in the receiving river/reservoir systems which can be applied to similar environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bacteria and Fungi Respond Differently to Multifactorial Climate Change in a Temperate Heathland, Traced with 13C-Glycine and FACE CO2

Science.gov (United States)

Andresen, Louise C.; Dungait, Jennifer A. J.; Bol, Roland; Selsted, Merete B.; Ambus, Per; Michelsen, Anders

2014-01-01

It is vital to understand responses of soil microorganisms to predicted climate changes, as these directly control soil carbon (C) dynamics. The rate of turnover of soil organic carbon is mediated by soil microorganisms whose activity may be affected by climate change. After one year of multifactorial climate change treatments, at an undisturbed temperate heathland, soil microbial community dynamics were investigated by injection of a very small concentration (5.12 µg C g−1 soil) of 13C-labeled glycine (13C2, 99 atom %) to soils in situ. Plots were treated with elevated temperature (+1°C, T), summer drought (D) and elevated atmospheric carbon dioxide (510 ppm [CO2]), as well as combined treatments (TD, TCO2, DCO2 and TDCO2). The 13C enrichment of respired CO2 and of phospholipid fatty acids (PLFAs) was determined after 24 h. 13C-glycine incorporation into the biomarker PLFAs for specific microbial groups (Gram positive bacteria, Gram negative bacteria, actinobacteria and fungi) was quantified using gas chromatography-combustion-stable isotope ratio mass spectrometry (GC-C-IRMS). Gram positive bacteria opportunistically utilized the freshly added glycine substrate, i.e. incorporated 13C in all treatments, whereas fungi had minor or no glycine derived 13C-enrichment, hence slowly reacting to a new substrate. The effects of elevated CO2 did suggest increased direct incorporation of glycine in microbial biomass, in particular in G+ bacteria, in an ecosystem subjected to elevated CO2. Warming decreased the concentration of PLFAs in general. The FACE CO2 was 13C-depleted (δ13C = 12.2‰) compared to ambient (δ13C = ∼−8‰), and this enabled observation of the integrated longer term responses of soil microorganisms to the FACE over one year. All together, the bacterial (and not fungal) utilization of glycine indicates substrate preference and resource partitioning in the microbial community, and therefore suggests a diversified response pattern to future

Bacteria and fungi respond differently to multifactorial climate change in a temperate heathland, traced with 13C-glycine and FACE CO2.

Directory of Open Access Journals (Sweden)

Louise C Andresen

Full Text Available It is vital to understand responses of soil microorganisms to predicted climate changes, as these directly control soil carbon (C dynamics. The rate of turnover of soil organic carbon is mediated by soil microorganisms whose activity may be affected by climate change. After one year of multifactorial climate change treatments, at an undisturbed temperate heathland, soil microbial community dynamics were investigated by injection of a very small concentration (5.12 µg C g(-1 soil of (13C-labeled glycine ((13C2, 99 atom % to soils in situ. Plots were treated with elevated temperature (+1°C, T, summer drought (D and elevated atmospheric carbon dioxide (510 ppm [CO2], as well as combined treatments (TD, TCO2, DCO2 and TDCO2. The (13C enrichment of respired CO2 and of phospholipid fatty acids (PLFAs was determined after 24 h. (13C-glycine incorporation into the biomarker PLFAs for specific microbial groups (Gram positive bacteria, Gram negative bacteria, actinobacteria and fungi was quantified using gas chromatography-combustion-stable isotope ratio mass spectrometry (GC-C-IRMS. Gram positive bacteria opportunistically utilized the freshly added glycine substrate, i.e. incorporated (13C in all treatments, whereas fungi had minor or no glycine derived (13C-enrichment, hence slowly reacting to a new substrate. The effects of elevated CO2 did suggest increased direct incorporation of glycine in microbial biomass, in particular in G(+ bacteria, in an ecosystem subjected to elevated CO2. Warming decreased the concentration of PLFAs in general. The FACE CO2 was (13C-depleted (δ(13C = 12.2‰ compared to ambient (δ(13C = ∼-8‰, and this enabled observation of the integrated longer term responses of soil microorganisms to the FACE over one year. All together, the bacterial (and not fungal utilization of glycine indicates substrate preference and resource partitioning in the microbial community, and therefore suggests a diversified response pattern to

EVALUATION OF MORPHOLOGICAL PARAMETERS OF FLOWERING BUDS AND FLOWERING ON ASIMINA TRILOBA (L. DUNAL IN THE CONTEXT OF CLIMATE CHANGE IN ROMANIA

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Beatrice Agneta Szilagyi

2017-07-01

Full Text Available In the context of climate change in Romania, we proposed to study the improvement of the country's flora by introducing an ornamental and beneficial species of temperate climate. Studies undertaken in spring 2017 indicate that Asimina triloba (L. Dunal flowers under conditions in Romania similar to those in the area of origin. Thus, we found that the beginning of vegetation in flowering buds took place in the first tenth of April and continued in stages until the start of the third trimester of April, when the flowering bud dimensions were over 15 mm in diameter, while the entire period of flowing took place from 24.04-20.05. One influence on the start of vegetation in flowing buds was the average daytime temperature recorded in the planting zone of Asimina triloba (L. Dunal studied, which compared with historical averages was twice as high.

Example Emergency Plan for Blue Marsh Dam and Lake.

Science.gov (United States)

1983-08-01

of 10 to 20 feet. The area is designated as seismic zone 2. d. Climate The project area is located in the temperate northeast Atlantic Coast climatic ...Hydrology and H ydr- aulics littncl shallI annia II Ai rekt a thorough inspection of all nriechani i al. electr-ical and other eq11inipmIent pr nent to

Carbon stock and carbon turnover in boreal and temperate forests - Integration of remote sensing data and global vegetation models

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Thurner, Martin; Beer, Christian; Carvalhais, Nuno; Forkel, Matthias; Tito Rademacher, Tim; Santoro, Maurizio; Tum, Markus; Schmullius, Christiane

2016-04-01

Long-term vegetation dynamics are one of the key uncertainties of the carbon cycle. There are large differences in simulated vegetation carbon stocks and fluxes including productivity, respiration and carbon turnover between global vegetation models. Especially the implementation of climate-related mortality processes, for instance drought, fire, frost or insect effects, is often lacking or insufficient in current models and their importance at global scale is highly uncertain. These shortcomings have been due to the lack of spatially extensive information on vegetation carbon stocks, which cannot be provided by inventory data alone. Instead, we recently have been able to estimate northern boreal and temperate forest carbon stocks based on radar remote sensing data. Our spatially explicit product (0.01° resolution) shows strong agreement to inventory-based estimates at a regional scale and allows for a spatial evaluation of carbon stocks and dynamics simulated by global vegetation models. By combining this state-of-the-art biomass product and NPP datasets originating from remote sensing, we are able to study the relation between carbon turnover rate and a set of climate indices in northern boreal and temperate forests along spatial gradients. We observe an increasing turnover rate with colder winter temperatures and longer winters in boreal forests, suggesting frost damage and the trade-off between frost adaptation and growth being important mortality processes in this ecosystem. In contrast, turnover rate increases with climatic conditions favouring drought and insect outbreaks in temperate forests. Investigated global vegetation models from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), including HYBRID4, JeDi, JULES, LPJml, ORCHIDEE, SDGVM, and VISIT, are able to reproduce observation-based spatial climate - turnover rate relationships only to a limited extent. While most of the models compare relatively well in terms of NPP, simulated

A review of the role of temperate forests in the global CO2 balance

International Nuclear Information System (INIS)

Musselman, R.C.; Fox, D.G.

1991-01-01

The role of temperate forests in the global carbon balance is difficult to determine because many uncertainties exist in the data, and many assumptions must be made in these determinations. Still, there is little doubt that increases in atmospheric CO 2 and global warming would have major effects on temperate forest ecosystems. Increases in atmospheric CO 2 may result in increases in photosynthesis, changes in water and nitrogen use efficiency, and changes in carbon allocation. Indirect effects of changes in global carbon balance on regional climate and on microenvironmental conditions, particularly temperature and moisture, may be more important then direct effects of increased CO 2 on vegetation. Increased incidence of forest perturbations might also be expected. The evidence suggests that conditions favorable to forest growth and development may exist in the northern latitudes, while southern latitude forests may undergo drought stress. Current harvest of temperate and world forests contributes substantial amounts of carbon to the atmosphere, possibly as much as 3 gigatons (Gt) per year. Return of this carbon to forest storage may require decades. Forest managers should be aware of the global as well as local impact their management decisions will have on the atmospheric carbon balance of the ecosystems they oversee

Reproductive performance of different breeds of broiler rabbits under sub-temperate climatic conditions

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D. Kumar

2013-09-01

Full Text Available This study was conducted to assess the effect of breed, season, age and weight of doe at mating on reproductive performance of 4 broiler rabbit breeds, Grey Giant, White Giant, Soviet Chinchilla, and New Zealand White, reared under standard management practices in sub-temperate climatic conditions of India. They were first mated at 6 to 7 mo of age, whereupon an extensive breeding system (re-mating after weaning was followed. Weaning was done 42 d after kindling. The data from the records on reproduction consisting of 503 matings and 377 kindlings were analysed. The parameters considered were fertility rate, litter size at birth (LSB, litter weight at birth (LWB, litter size at weaning (LSW, litter weight at weaning (LWW, doe weight at mating (DWM, gestation length and sex ratio. Among 4 breeds, the LSB, LWB and LSW were higher in Grey Giant followed by White Giant, Soviet Chinchilla and New Zealand White. The LSB and LSW in Grey Giant breed differed significantly (P<0.05 from Soviet Chinchilla and New Zealand White. Season had significant (P<0.05 effect on LSW with higher values during spring (5.68±0.24, followed by summer (5.29±0.30, winter (5.13±0.25 and autumn (4.17±0.49. The body weight of doe at service significantly influenced fertility. The fertility increased as body weight increased. The age of the doe at mating had a significant effect on LSW, with higher values for does more than 2 yr and less than 1 yr old compared to 1- to 2-yr old does. The parity did not affect any of the parameters studied. It is concluded that the factors studied affect the reproductive performance of rabbit does. Grey Giant breed showed the highest litter size at birth and weaning, and the highest litter size and weight at weaning was in spring.

Spatio-temporal trends of nitrogen deposition and climate effects on Sphagnum productivity in European peatlands

International Nuclear Information System (INIS)

Granath, Gustaf; Limpens, Juul; Posch, Maximilian; Mücher, Sander; Vries, Wim de

2014-01-01

To quantify potential nitrogen (N) deposition impacts on peatland carbon (C) uptake, we explored temporal and spatial trends in N deposition and climate impacts on the production of the key peat forming functional group (Sphagnum mosses) across European peatlands for the period 1900–2050. Using a modelling approach we estimated that between 1900 and 1950 N deposition impacts remained limited irrespective of geographical position. Between 1950 and 2000 N deposition depressed production between 0 and 25% relative to 1900, particularly in temperate regions. Future scenarios indicate this trend will continue and become more pronounced with climate warming. At the European scale, the consequences for Sphagnum net C-uptake remained small relative to 1900 due to the low peatland cover in high-N areas. The predicted impacts of likely changes in N deposition on Sphagnum productivity appeared to be less than those of climate. Nevertheless, current critical loads for peatlands are likely to hold under a future climate. - Highlights: • We model the effect of N deposition combined with climate on production of Sphagnum between 1900 and 2050. • Spatially explicit projections are indicated on an updated European peatland distribution map. • Results stress the vulnerability of temperate Sphagnum peatlands to current and future N deposition. • Future impacts of N deposition on Sphagnum productivity likely depend more on climate change than on N deposition rate. - Temperate Sphagnum peatlands are vulnerable to current and future N deposition and current critical loads for peatlands are likely to hold under a future climate

Synchronous turnover of flora, fauna, and climate at the Eocene–Oligocene Boundary in Asia

Science.gov (United States)

Sun, Jimin; Ni, Xijun; Bi, Shundong; Wu, Wenyu; Ye, Jie; Meng, Jin; Windley, Brian F.

2014-01-01

The Eocene–Oligocene Boundary (~34 million years ago) marks one of the largest extinctions of marine invertebrates in the world oceans and of mammalian fauna in Europe and Asia in the Cenozoic era. A shift to a cooler climate across this boundary has been suggested as the cause of this extinction in the marine environment, but there is no manifold evidence for a synchronous turnover of flora, fauna and climate at the Eocene–Oligocene Boundary in a single terrestrial site in Asia to support this hypothesis. Here we report new data of magnetostratigraphy, pollen and climatic proxies in the Asian interior across the Eocene–Oligocene Boundary; our results show that climate change forced a turnover of flora and fauna, suggesting there was a change from large-size perissodactyl-dominant fauna in forests under a warm-temperate climate to small rodent/lagomorph-dominant fauna in forest-steppe in a dry-temperate climate across the Eocene–Oligocene Boundary. These data provide a new terrestrial record for this significant Cenozoic environmental event. PMID:25501388

Synchronous turnover of flora, fauna, and climate at the Eocene-Oligocene Boundary in Asia.

Science.gov (United States)

Sun, Jimin; Ni, Xijun; Bi, Shundong; Wu, Wenyu; Ye, Jie; Meng, Jin; Windley, Brian F

2014-12-12

The Eocene-Oligocene Boundary (~34 million years ago) marks one of the largest extinctions of marine invertebrates in the world oceans and of mammalian fauna in Europe and Asia in the Cenozoic era. A shift to a cooler climate across this boundary has been suggested as the cause of this extinction in the marine environment, but there is no manifold evidence for a synchronous turnover of flora, fauna and climate at the Eocene-Oligocene Boundary in a single terrestrial site in Asia to support this hypothesis. Here we report new data of magnetostratigraphy, pollen and climatic proxies in the Asian interior across the Eocene-Oligocene Boundary; our results show that climate change forced a turnover of flora and fauna, suggesting there was a change from large-size perissodactyl-dominant fauna in forests under a warm-temperate climate to small rodent/lagomorph-dominant fauna in forest-steppe in a dry-temperate climate across the Eocene-Oligocene Boundary. These data provide a new terrestrial record for this significant Cenozoic environmental event.

Attributing the effects of climate on phenology change suggests high sensitivity in coastal zones

Science.gov (United States)

Seyednasrollah, B.; Clark, J. S.

2015-12-01

The impact of climate change on spring phenology depends on many variables that cannot be separated using current models. Phenology can influence carbon sequestration, plant nutrition, forest health, and species distributions. Leaf phenology is sensitive to changes of environmental factors, including climate, species composition, latitude, and solar radiation. The many variables and their interactions frustrate efforts to attribute variation to climate change. We developed a Bayesian framework to quantify the influence of environment on the speed of forest green-up. This study presents a state-space hierarchical model to infer and predict change in forest greenness over time using satellite observations and ground measurements. The framework accommodates both observation and process errors and it allows for main effects of variables and their interactions. We used daily spaceborne remotely sensed data from the Moderate Resolution Imaging Spectroradiometer (MODIS) to quantify temporal variability in the enhanced vegetation index (EVI) along a habitat gradient in the Southeastern United States. The ground measurements of meteorological parameters are obtained from study sites located in the Appalachian Mountains, the Piedmont and the Atlantic Coastal Plain between years 2000 and 2015. Results suggest that warming accelerates spring green-up in the Coastal Plain to a greater degree than in the Piedmont and Appalachian. In other words, regardless of variation in the timing of spring onset, the rate of greenness in non-coastal zones decreases with increasing temperature and hence with time over the spring transitional period. However, in coastal zones, as air temperature increases, leaf expansion becomes faster. This may indicate relative vulnerability to warming in non-coastal regions where moisture could be a limiting factor, whereas high temperatures in regions close to the coast enhance forest physiological activities. Model predictions agree with the remotely

Spatial variation in the storages and age-related dynamics of forest carbon sequestration in different climate zones-evidence from black locust plantations on the Loess Plateau of China.

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Taijun Li

Full Text Available Knowledge about the long-term influences of climate change on the amount of potential carbon (C sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L. in the semi-arid and semi-humid zones of China's Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p < 0.001. The C carrying capacity of the plantations was measured at 166.4 Mg C ha-1 (1 Mg = 106 g in the semi-humid zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha-1. Soil organic C (SOC increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010. However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y. The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011, yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha-1 to 28.4 Mg C ha-1 during the old forest stage (38 to 56 y. The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y, the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration.

Parallel tempering in full QCD with Wilson fermions

International Nuclear Information System (INIS)

Ilgenfritz, E.-M.; Kerler, W.; Mueller-Preussker, M.; Stueben, H.

2002-01-01

We study the performance of QCD simulations with dynamical Wilson fermions by combining the hybrid Monte Carlo algorithm with parallel tempering on 10 4 and 12 4 lattices. In order to compare tempered with standard simulations, covariance matrices between subensembles have to be formulated and evaluated using the general properties of autocorrelations of the parallel tempering algorithm. We find that rendering the hopping parameter κ dynamical does not lead to an essential improvement. We point out possible reasons for this observation and discuss more suitable ways of applying parallel tempering to QCD

Study on tempering behaviour of AISI 410 stainless steel

Energy Technology Data Exchange (ETDEWEB)

Chakraborty, Gopa, E-mail: gopa_mjs@igcar.gov.in [Metallurgy & Materials Group, Indira Gandhi Center for Atomic Research, Kalpakkam 603102 (India); Das, C.R.; Albert, S.K.; Bhaduri, A.K.; Thomas Paul, V. [Metallurgy & Materials Group, Indira Gandhi Center for Atomic Research, Kalpakkam 603102 (India); Panneerselvam, G. [Chemistry Group, Indira Gandhi Center for Atomic Research, Kalpakkam 603102 (India); Dasgupta, Arup [Metallurgy & Materials Group, Indira Gandhi Center for Atomic Research, Kalpakkam 603102 (India)

2015-02-15

Martensitic stainless steels find extensive applications due to their optimum combination of strength, hardness and wear-resistance in tempered condition. However, this class of steels is susceptible to embrittlement during tempering if it is carried out in a specific temperature range resulting in significant reduction in toughness. Embrittlement of as-normalised AISI 410 martensitic stainless steel, subjected to tempering treatment in the temperature range of 673–923 K was studied using Charpy impact tests followed by metallurgical investigations using field emission scanning electron and transmission electron microscopes. Carbides precipitated during tempering were extracted by electrochemical dissolution of the matrix and identified by X-ray diffraction. Studies indicated that temper embrittlement is highest when the steel is tempered at 823 K. Mostly iron rich carbides are present in the steel subjected to tempering at low temperatures of around 723 K, whereas chromium rich carbides (M{sub 23}C{sub 6}) dominate precipitation at high temperature tempering. The range 773–823 K is the transition temperature range for the precipitates, with both Fe{sub 2}C and M{sub 23}C{sub 6} types of carbides coexisting in the material. The nucleation of Fe{sub 2}C within the martensite lath, during low temperature tempering, has a definite role in the embrittlement of this steel. Embrittlement is not observed at high temperature tempering because of precipitation of M{sub 23}C{sub 6} carbides, instead of Fe{sub 2}C, preferentially along the lath and prior austenite boundaries. Segregation of S and P, which is widely reported as one of the causes for temper embrittlement, could not be detected in the material even through Auger electron spectroscopy studies. - Highlights: • Tempering behaviour of AISI 410 steel is studied within 673–923 K temperature range. • Temperature regime of maximum embrittlement is identified as 773–848 K. • Results show that type of

Potential Environmental and Ecological Effects of Global Climate Change on Venomous Terrestrial Species in the Wilderness.

Science.gov (United States)

Needleman, Robert K; Neylan, Isabelle P; Erickson, Timothy

2018-06-01

Climate change has been scientifically documented, and its effects on wildlife have been prognosticated. We sought to predict the overall impact of climate change on venomous terrestrial species. We hypothesize that given the close relationship between terrestrial venomous species and climate, a changing global environment may result in increased species migration, geographical redistribution, and longer seasons for envenomation, which would have repercussions on human health. A retrospective analysis of environmental, ecological, and medical literature was performed with a focus on climate change, toxinology, and future modeling specific to venomous terrestrial creatures. Species included venomous reptiles, snakes, arthropods, spiders, and Hymenoptera (ants and bees). Animals that are vectors of hemorrhagic infectious disease (eg, mosquitos, ticks) were excluded. Our review of the literature indicates that changes to climatic norms will have a potentially dramatic effect on terrestrial venomous creatures. Empirical evidence demonstrates that geographic distributions of many species have already shifted due to changing climatic conditions. Given that most terrestrial venomous species are ectotherms closely tied to ambient temperature, and that climate change is shifting temperature zones away from the equator, further significant distribution and population changes should be anticipated. For those species able to migrate to match the changing temperatures, new geographical locations may open. For those species with limited distribution capabilities, the rate of climate change may accelerate faster than species can adapt, causing population declines. Specifically, poisonous snakes and spiders will likely maintain their population numbers but will shift their geographic distribution to traditionally temperate zones more often inhabited by humans. Fire ants and Africanized honey bees are expected to have an expanded range distribution due to predicted warming trends

Analysis of Small ruminant market system in different agro-climatic zones of Southern India

Directory of Open Access Journals (Sweden)

D Ramesh

2012-10-01

Full Text Available This study examines the marketing system of small ruminants in three different agro-climatic zones of Karnataka in India. Multistage random sampling technique was used to select 60 small ruminant farmers from three viz. Bijapur (Arid zone, Gulbarga (Semi-arid zone and Udupi (Coastal zone district of Karnataka state. A structured questionnaire which had earlier been subject to face validity and has a reliability coefficient of 0.87 was used to collect data from the samples respondents. Data was analysed using statistical package for social science (SPSS.The results of the study revealed that marketing of small ruminants is haphazard in the study areas. Majority of the respondents (85% sold their animal when they needed cash for home consumption followed by to pay off loan (28.3% was the main reason to sell their animals. Important marketing channels were relatives and friends, local markets and village collectors. Farmers gave different reasons for selling their animals through different channels. Majority of the farmers used relatives and friends as one of the marketing channels. Most of farmers also felt that there was a difference in the price offered by village collectors and the price they were getting in the livestock markets. And a few of them were of the opinion that village collectors were not reliable in marketing. Price of the animals was establishing based on the body confirmation of the animal. Study also revealed that injured animals fetch less value than the healthy animals. [Vet. World 2012; 5(5.000: 288-293

Environmental Change: Precipitation and N, P, K, mg Fertilization Influences on Crop Yield Under Temperate Climate Conditions

Science.gov (United States)

László Phd, Dd. M.

2009-04-01

Summary: Agroecological quality has a well estabished dependence on climate-rainfall changes because the water problems are pressing. Therefore, there is, growing concern about the potentially wide ranging risks that climate change would have on these key industries as the nature and extent of anticipated changes have become more evident. It also includes changes in land use and in plant production and their management. These changes are unprecedented in terms of both their rate and their spatial extent. Changes in land use (agrotechnics, soil, cultivation, fertility, quality, protection etc.) and in plant production (plant, nutrition, rotation, protection etc.) are currently the main manifestations. As an interdisciplinary problem it is necessary to study such a complex matter in terms of agricultural production. Generally, among natural catastrophes, droughts and floods cause the greatest problems in field crop production. The droughts and the floods that were experienced in Hungary in the early 1980s have drawn renewed attention to the analyses of these problems. New research on climate change-soil-plant systems are focused on yield and yield quality. This paper reports of the climate changes (rainfall); soil (acidic sandy brown forest) properties, mineral N, P, K, Mg fertilisation level and plant interactions on rye (Secale cereale L.), on potato (Solanum tuberosum L.) and on winter wheat (Triticum aestivum L.) yields in a long term field experiment set up at Nyírlugos in north-eastern Hungary under temperate climate conditions in 1962. Results are summarised from 1962 to 1990. Main conclusions were as follows: 1. Rye: a, Experimental years were characterised by frequent extremes of precipitation variabilities and changes. b, By an average year, at a satisfactory fertilisation level (N: 90 kg ha-1 and NP, NK, NPK, NPKMg combinations) the maximum yield reached 3.8 t ha-1. But yield was decreased by 17% and by 52% due to drought and excess rainfall, respectively

Tempering of Low-Temperature Bainite

Science.gov (United States)

Peet, Mathew J.; Babu, Sudarsanam Suresh; Miller, Mike K.; Bhadeshia, H. K. D. H.

2017-07-01

Electron microscopy, X-ray diffraction, and atom probe tomography have been used to identify the changes which occur during the tempering of a carbide-free bainitic steel transformed at 473 K (200 °C). Partitioning of solute between ferrite and thin-films of retained austenite was observed on tempering at 673 K (400 °C) for 30 minutes. After tempering at 673 K (400 °C) and 773 K (500 °C) for 30 minutes, cementite was observed in the form of nanometre scale precipitates. Proximity histograms showed that the partitioning of solutes other than silicon from the cementite was slight at 673 K (400 °C) and more obvious at 773 K (500 °C). In both cases, the nanometre scale carbides are greatly depleted in silicon.

Climate-Induced Larch Growth Response Within the Central Siberian Permafrost Zone

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Kharuk, Viacheslav I.; Ranson, Kenneth J.; Im, Sergei T.; Petrov, Il'ya A.

2015-01-01

Aim: estimation of larch (Larix gmelinii) growth response to current climate changes. Location: permafrost area within the northern part of Central Siberia (approximately 65.8 deg N, 98.5 deg E). Method: analysis of dendrochronological data, climate variables, drought index SPEI, GPP (gross primary production) and EVI vegetation index (both Aqua/MODIS satellite derived), and soil water content anomalies (GRACE satellite measurements of equivalent water thickness anomalies, EWTA). Results: larch tree ring width (TRW) correlated with previous year August precipitation (r = 0.63), snow accumulation (r = 0.61), soil water anomalies (r = 0.79), early summer temperatures and water vapor pressure (r = 0.73 and r = 0.69, respectively), May and June drought index (r = 0.68-0.82). There are significant positive trends of TRW since late 1980s and GPP since the year 2000. Mean TRW increased by about 50%, which is similar to post-Little Ice Age warming. TRW correlated with GPP and EVI of larch stands (r = 0.68-0.69). Main conclusions: within the permafrost zone of central Siberia larch TRW growth is limited by early summer temperatures, available water from snowmelt, water accumulated within soil in the previous year, and permafrost thaw water. Water stress is one of the limiting factors of larch growth. Larch TRW growth and GPP increased during recent decades.

Forecasting carbon budget under climate change and CO2 fertilization for subtropical region in China using integrated biosphere simulator (IBIS) model

Science.gov (United States)

Zhu, Q.; Jiang, H.; Liu, J.; Peng, C.; Fang, X.; Yu, S.; Zhou, G.; Wei, X.; Ju, W.

2011-01-01

The regional carbon budget of the climatic transition zone may be very sensitive to climate change and increasing atmospheric CO2 concentrations. This study simulated the carbon cycles under these changes using process-based ecosystem models. The Integrated Biosphere Simulator (IBIS), a Dynamic Global Vegetation Model (DGVM), was used to evaluate the impacts of climate change and CO2 fertilization on net primary production (NPP), net ecosystem production (NEP), and the vegetation structure of terrestrial ecosystems in Zhejiang province (area 101,800 km2, mainly covered by subtropical evergreen forest and warm-temperate evergreen broadleaf forest) which is located in the subtropical climate area of China. Two general circulation models (HADCM3 and CGCM3) representing four IPCC climate change scenarios (HC3AA, HC3GG, CGCM-sresa2, and CGCM-sresb1) were used as climate inputs for IBIS. Results show that simulated historical biomass and NPP are consistent with field and other modelled data, which makes the analysis of future carbon budget reliable. The results indicate that NPP over the entire Zhejiang province was about 55 Mt C yr-1 during the last half of the 21st century. An NPP increase of about 24 Mt C by the end of the 21st century was estimated with the combined effects of increasing CO2 and climate change. A slight NPP increase of about 5 Mt C was estimated under the climate change alone scenario. Forests in Zhejiang are currently acting as a carbon sink with an average NEP of about 2.5 Mt C yr-1. NEP will increase to about 5 Mt C yr-1 by the end of the 21st century with the increasing atmospheric CO2 concentration and climate change. However, climate change alone will reduce the forest carbon sequestration of Zhejiang's forests. Future climate warming will substantially change the vegetation cover types; warm-temperate evergreen broadleaf forest will be gradually substituted by subtropical evergreen forest. An increasing CO2 concentration will have little

An index-based method to assess risks of climate-related hazards in coastal zones: The case of Tetouan

Science.gov (United States)

Satta, Alessio; Snoussi, Maria; Puddu, Manuela; Flayou, Latifa; Hout, Radouane

2016-06-01

The regional risk assessment carried out within the ClimVar & ICZM Project identified the coastal zone of Tetouan as a hotspot of the Mediterranean Moroccan coast and so it was chosen for the application of the Multi-Scale Coastal Risk Index for Local Scale (CRI-LS). The local scale approach provides a useful tool for local coastal planning and management by exploring the effects and the extensions of the hazards and combining hazard, vulnerability and exposure variables in order to identify areas where the risk is relatively high. The coast of Tetouan is one of the coastal areas that have been most rapidly and densely urbanized in Morocco and it is characterized by an erosive shoreline. Local authorities are facing the complex task of balancing development and managing coastal risks, especially coastal erosion and flooding, and then be prepared to the unavoidable impacts of climate change. The first phase of the application of the CRI-LS methodology to Tetouan consisted of defining the coastal hazard zone, which results from the overlaying of the erosion hazard zone and the flooding hazard zone. Nineteen variables were chosen to describe the Hazards, Vulnerability and Exposure factors. The scores corresponding to each variable were calculated and the weights assigned through an expert judgement elicitation. The resulting values are hosted in a geographic information system (GIS) platform that enables the individual variables and aggregated risk scores to be color-coded and mapped across the coastal hazard zone. The results indicated that 10% and 27% of investigated littoral fall under respectively very high and high vulnerability because of combination of high erosion rates with high capital land use. The risk map showed that some areas, especially the flood plains of Restinga, Smir and Martil-Alila, with distances over 5 km from the coast, are characterized by high levels of risk due to the low topography of the flood plains and to the high values of exposure

Habitat use by larval fishes in a temperate South African surf zone

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Watt-Pringle, Peter; Strydom, Nadine A.

2003-12-01

Larval fishes were sampled in the Kwaaihoek surf zone on the south east coast of South Africa. On six occasions between February and May 2002, larval fishes were collected in two habitat types identified in the inner surf zone using a modified beach-seine net. The surf zone habitats were classified as either sheltered trough areas or adjacent exposed surf areas. Temperature, depth and current measurements were taken at all sites. Trough habitats consisted of a depression in surf topography characterised by reduced current velocities and greater average depth than adjacent surf areas. In total, 325 larval fishes were collected. Of these, 229 were collected in trough and 96 in surf habitats. At least 22 families and 37 species were represented in the catch. Dominant families were the Mugilidae, Sparidae, Atherinidae, and Engraulidae. Dominant species included Liza tricuspidens and Liza richardsonii (Mugilidae), Rhabdosargus holubi and Sarpa salpa (Sparidae), Atherina breviceps (Atherinidae) and Engraulis japonicus (Engraulide). Mean CPUE of postflexion larvae of estuary-dependent species was significantly greater in trough areas. The proportion of postflexion larval fishes in trough habitat was significantly greater than that of preflexion stages, a result that was not apparent in surf habitat sampled. CPUE of postflexion larvae of estuary-dependent fishes was negatively correlated with current magnitude and positively correlated with habitat depth. Mean body length of larval fishes was significantly greater in trough than in surf habitats. These results provide evidence that the CPUE of postflexion larvae of estuary-dependent fishes is higher in trough habitat in the surf zone and this may be indicative of active habitat selection for areas of reduced current velocity/wave action. The implications of this behaviour for estuarine recruitment processes are discussed.

Climate-Induced Landsliding within the Larch Dominant Permafrost Zone of Central Siberia

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Kharuk, Viacheslav I.; Shushpanov, Alexandr S.; Im, Sergei T.; Ranson, Kenneth J.

2016-01-01

Climate impact on landslide occurrence and spatial patterns were analyzed within the larch-dominant communities associated with continuous permafrost areas of central Siberia. We used high resolution satellite imagery (i.e. QuickBird, WorldView) to identify landslide scars over an area of 62 000 km2. Landslide occurrence was analyzed with respect to climate variables (air temperature, precipitation, drought index SPEI), and Gravity Recovery and Climate Experiment satellite derived equivalent of water thickness anomalies (EWTA). Landslides were found only on southward facing slopes, and the occurrence of landslides increased exponentially with increasing slope steepness. Lengths of landslides correlated positively with slope steepness. The observed upper elevation limit of landslides tended to coincide with the tree line. Observations revealed landslides occurrence was also found to be strongly correlated with August precipitation (r = 0.81) and drought index (r = 0.7), with June-July-August soil water anomalies (i.e., EWTA, r = 0.68-0.7), and number of thawing days (i.e., a number of days with t (max) > 0 deg C; r = 0.67). A significant increase in the variance of soil water anomalies was observed, indicating that occurrence of landslides may increase even with a stable mean precipitation level. The key-findings of this study are (1) landslides occurrence increased within the permafrost zone of central Siberia in the beginning of the 21st century; (2) the main cause of increased landslides occurrence are extremes in precipitation and soil water anomalies; and (3) landslides occurrence are strongly dependent on relief features such as southward facing steep slopes.

Climate change induced transformations of agricultural systems: insights from a global model

Science.gov (United States)

Leclère, D.; Havlík, P.; Fuss, S.; Schmid, E.; Mosnier, A.; Walsh, B.; Valin, H.; Herrero, M.; Khabarov, N.; Obersteiner, M.

2014-12-01

Climate change might impact crop yields considerably and anticipated transformations of agricultural systems are needed in the coming decades to sustain affordable food provision. However, decision-making on transformational shifts in agricultural systems is plagued by uncertainties concerning the nature and geography of climate change, its impacts, and adequate responses. Locking agricultural systems into inadequate transformations costly to adjust is a significant risk and this acts as an incentive to delay action. It is crucial to gain insight into how much transformation is required from agricultural systems, how robust such strategies are, and how we can defuse the associated challenge for decision-making. While implementing a definition related to large changes in resource use into a global impact assessment modelling framework, we find transformational adaptations to be required of agricultural systems in most regions by 2050s in order to cope with climate change. However, these transformations widely differ across climate change scenarios: uncertainties in large-scale development of irrigation span in all continents from 2030s on, and affect two-thirds of regions by 2050s. Meanwhile, significant but uncertain reduction of major agricultural areas affects the Northern Hemisphere’s temperate latitudes, while increases to non-agricultural zones could be large but uncertain in one-third of regions. To help reducing the associated challenge for decision-making, we propose a methodology exploring which, when, where and why transformations could be required and uncertain, by means of scenario analysis.

Climate change induced transformations of agricultural systems: insights from a global model

International Nuclear Information System (INIS)

Leclère, D; Havlík, P; Mosnier, A; Walsh, B; Valin, H; Khabarov, N; Obersteiner, M; Fuss, S; Schmid, E; Herrero, M

2014-01-01

Climate change might impact crop yields considerably and anticipated transformations of agricultural systems are needed in the coming decades to sustain affordable food provision. However, decision-making on transformational shifts in agricultural systems is plagued by uncertainties concerning the nature and geography of climate change, its impacts, and adequate responses. Locking agricultural systems into inadequate transformations costly to adjust is a significant risk and this acts as an incentive to delay action. It is crucial to gain insight into how much transformation is required from agricultural systems, how robust such strategies are, and how we can defuse the associated challenge for decision-making. While implementing a definition related to large changes in resource use into a global impact assessment modelling framework, we find transformational adaptations to be required of agricultural systems in most regions by 2050s in order to cope with climate change. However, these transformations widely differ across climate change scenarios: uncertainties in large-scale development of irrigation span in all continents from 2030s on, and affect two-thirds of regions by 2050s. Meanwhile, significant but uncertain reduction of major agricultural areas affects the Northern Hemisphere’s temperate latitudes, while increases to non-agricultural zones could be large but uncertain in one-third of regions. To help reducing the associated challenge for decision-making, we propose a methodology exploring which, when, where and why transformations could be required and uncertain, by means of scenario analysis. (letter)

Global forest sector modeling: application to some impacts of climate change

Science.gov (United States)

Joseph. Buongiorno

2016-01-01

This paper explored the potential long-term effects of a warming climate on the global wood sector, based on Way and Oren's synthesis (Tree Physiology 30,669-688) indicating positive responses of tree growth to higher temperature in boreal and temperative climates, and negative responses in the topics. Changes in forest productivity were introduced in the Global...

WARMER URBAN CLIMATES FOR DEVELOPMENT OF GREEN SPACES IN NORTHERN SIBERIAN CITIES

Directory of Open Access Journals (Sweden)

Igor Esau

2016-01-01

Full Text Available Modern human societies have accumulated considerable power to modify their environment and the earth’s system climate as the whole. The most significant environmental changes are found in the urbanized areas. This study considers coherent changes in vegetation productivity and land surface temperature (LST around four northern West Siberian cities, namely, Tazovsky, Nadym, Noyabrsk and Megion. These cities are located in tundra, forest-tundra, northern taiga and middle taiga bioclimatic zones correspondingly. Our analysis of 15 years (2000–2014 Moderate Resolution Imaging Spectroradiometer (MODIS data revealed significantly (1.3 °C to 5.2 °C warmer seasonally averaged LST within the urbanized territories than those of the surrounding landscapes. The magnitude of the urban LST anomaly corresponds to climates found 300–600 km to the South. In the climate change perspective, this magnitude corresponds to the expected regional warming by the middle or the end of the 21st century. Warmer urban climates, and specifically warmer upper soil layers, can support re-vegetation of the disturbed urban landscapes with more productive trees and tall shrubs. This afforestation is welcome by the migrant city population as it is more consistent with their traditional ecological knowledge. Survival of atypical, southern plant species encourages a number of initiatives and investment to introduce even broader spectrum of temperate blossoming trees and shrubs in urban landscapes. The unintended changes of the urban micro-climates in combination with knowledgeable urban planning could transform the Siberian pioneer settlements into places of belonging.

The Effect of Tempering on Strength Properties and Seed Coat ...

African Journals Online (AJOL)

The effect of tempering on seed coat adhesion strength and mechanical strength of sorghum and millet grain kernels was investigated at different tempering durations. Tempering reduced the kernel breaking strength and had significant effect on seed coat adhesion strength. Tempering the grain for 60 minutes at ambient ...

Responses of terrestrial ecosystems' net primary productivity to future regional climate change in China.

Science.gov (United States)

Zhao, Dongsheng; Wu, Shaohong; Yin, Yunhe

2013-01-01

The impact of regional climate change on net primary productivity (NPP) is an important aspect in the study of ecosystems' response to global climate change. China's ecosystems are very sensitive to climate change owing to the influence of the East Asian monsoon. The Lund-Potsdam-Jena Dynamic Global Vegetation Model for China (LPJ-CN), a global dynamical vegetation model developed for China's terrestrial ecosystems, was applied in this study to simulate the NPP changes affected by future climate change. As the LPJ-CN model is based on natural vegetation, the simulation in this study did not consider the influence of anthropogenic activities. Results suggest that future climate change would have adverse effects on natural ecosystems, with NPP tending to decrease in eastern China, particularly in the temperate and warm temperate regions. NPP would increase in western China, with a concentration in the Tibetan Plateau and the northwest arid regions. The increasing trend in NPP in western China and the decreasing trend in eastern China would be further enhanced by the warming climate. The spatial distribution of NPP, which declines from the southeast coast to the northwest inland, would have minimal variation under scenarios of climate change.

Responses of terrestrial ecosystems' net primary productivity to future regional climate change in China.

Directory of Open Access Journals (Sweden)

Dongsheng Zhao

Full Text Available The impact of regional climate change on net primary productivity (NPP is an important aspect in the study of ecosystems' response to global climate change. China's ecosystems are very sensitive to climate change owing to the influence of the East Asian monsoon. The Lund-Potsdam-Jena Dynamic Global Vegetation Model for China (LPJ-CN, a global dynamical vegetation model developed for China's terrestrial ecosystems, was applied in this study to simulate the NPP changes affected by future climate change. As the LPJ-CN model is based on natural vegetation, the simulation in this study did not consider the influence of anthropogenic activities. Results suggest that future climate change would have adverse effects on natural ecosystems, with NPP tending to decrease in eastern China, particularly in the temperate and warm temperate regions. NPP would increase in western China, with a concentration in the Tibetan Plateau and the northwest arid regions. The increasing trend in NPP in western China and the decreasing trend in eastern China would be further enhanced by the warming climate. The spatial distribution of NPP, which declines from the southeast coast to the northwest inland, would have minimal variation under scenarios of climate change.

Response of spatial vegetation distribution in China to climate changes since the Last Glacial Maximum (LGM)

Science.gov (United States)

Wang, Siyang; Xu, Xiaoting; Shrestha, Nawal; Zimmermann, Niklaus E.; Tang, Zhiyao; Wang, Zhiheng

2017-01-01

Analyzing how climate change affects vegetation distribution is one of the central issues of global change ecology as this has important implications for the carbon budget of terrestrial vegetation. Mapping vegetation distribution under historical climate scenarios is essential for understanding the response of vegetation distribution to future climatic changes. The reconstructions of palaeovegetation based on pollen data provide a useful method to understand the relationship between climate and vegetation distribution. However, this method is limited in time and space. Here, using species distribution model (SDM) approaches, we explored the climatic determinants of contemporary vegetation distribution and reconstructed the distribution of Chinese vegetation during the Last Glacial Maximum (LGM, 18,000 14C yr BP) and Middle-Holocene (MH, 6000 14C yr BP). The dynamics of vegetation distribution since the LGM reconstructed by SDMs were largely consistent with those based on pollen data, suggesting that the SDM approach is a useful tool for studying historical vegetation dynamics and its response to climate change across time and space. Comparison between the modeled contemporary potential natural vegetation distribution and the observed contemporary distribution suggests that temperate deciduous forests, subtropical evergreen broadleaf forests, temperate deciduous shrublands and temperate steppe have low range fillings and are strongly influenced by human activities. In general, the Tibetan Plateau, North and Northeast China, and the areas near the 30°N in Central and Southeast China appeared to have experienced the highest turnover in vegetation due to climate change from the LGM to the present. PMID:28426780

Climate Change Amplifications of Climate-Fire Teleconnections in the Southern Hemisphere

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Mariani, Michela; Holz, Andrés.; Veblen, Thomas T.; Williamson, Grant; Fletcher, Michael-Shawn; Bowman, David M. J. S.

2018-05-01

Recent changes in trend and variability of the main Southern Hemisphere climate modes are driven by a variety of factors, including increasing atmospheric greenhouse gases, changes in tropical sea surface temperature, and stratospheric ozone depletion and recovery. One of the most important implications for climatic change is its effect via climate teleconnections on natural ecosystems, water security, and fire variability in proximity to populated areas, thus threatening human lives and properties. Only sparse and fragmentary knowledge of relationships between teleconnections, lightning strikes, and fire is available during the observed record within the Southern Hemisphere. This constitutes a major knowledge gap for undertaking suitable management and conservation plans. Our analysis of documentary fire records from Mediterranean and temperate regions across the Southern Hemisphere reveals a critical increased strength of climate-fire teleconnections during the onset of the 21st century including a tight coupling between lightning-ignited fire occurrences, the upward trend in the Southern Annular Mode, and rising temperatures across the Southern Hemisphere.

Summertime elemental mercury exchange of temperate grasslands on an ecosystem-scale

Science.gov (United States)

Fritsche, J.; Wohlfahrt, G.; Ammann, C.; Zeeman, M.; Hammerle, A.; Obrist, D.; Alewell, C.

2013-01-01

In order to estimate the air-surface mercury exchange of grasslands in temperate climate regions, fluxes of gaseous elemental mercury (GEM) were measured at two sites in Switzerland and one in Austria during summer 2006. Two classic micrometeorological methods (aerodynamic and modified Bowen ratio) have been applied to estimate net GEM exchange rates and to determine the response of the GEM flux to changes in environmental conditions (e.g. heavy rain, summer ozone) on an ecosystem-scale. Both methods proved to be appropriate to estimate fluxes on time scales of a few hours and longer. Average dry deposition rates up to 4.3 ng m−2 h−1 and mean deposition velocities up to 0.10 cm s−1 were measured, which indicates that during the active vegetation period temperate grasslands are a small net sink for atmospheric mercury. With increasing ozone concentrations depletion of GEM was observed, but could not be quantified from the flux signal. Night-time deposition fluxes of GEM were measured and seem to be the result of mercury co-deposition with condensing water. Effects of grass cuts could also be observed, but were of minor magnitude. PMID:24348525

Forest structure and downed woody debris in boreal, temperate, and tropical forest fragments.

Science.gov (United States)

Gould, William A; González, Grizelle; Hudak, Andrew T; Hollingsworth, Teresa Nettleton; Hollingsworth, Jamie

2008-12-01

Forest fragmentation affects the heterogeneity of accumulated fuels by increasing the diversity of forest types and by increasing forest edges. This heterogeneity has implications in how we manage fuels, fire, and forests. Understanding the relative importance of fragmentation on woody biomass within a single climatic regime, and along climatic gradients, will improve our ability to manage forest fuels and predict fire behavior. In this study we assessed forest fuel characteristics in stands of differing moisture, i.e., dry and moist forests, structure, i.e., open canopy (typically younger) vs. closed canopy (typically older) stands, and size, i.e., small (10-14 ha), medium (33 to 60 ha), and large (100-240 ha) along a climatic gradient of boreal, temperate, and tropical forests. We measured duff, litter, fine and coarse woody debris, standing dead, and live biomass in a series of plots along a transect from outside the forest edge to the fragment interior. The goal was to determine how forest structure and fuel characteristics varied along this transect and whether this variation differed with temperature, moisture, structure, and fragment size. We found nonlinear relationships of coarse woody debris, fine woody debris, standing dead and live tree biomass with mean annual median temperature. Biomass for these variables was greatest in temperate sites. Forest floor fuels (duff and litter) had a linear relationship with temperature and biomass was greatest in boreal sites. In a five-way multivariate analysis of variance we found that temperature, moisture, and age/structure had significant effects on forest floor fuels, downed woody debris, and live tree biomass. Fragment size had an effect on forest floor fuels and live tree biomass. Distance from forest edge had significant effects for only a few subgroups sampled. With some exceptions edges were not distinguishable from interiors in terms of fuels.

Adaptation of maize to temperate climates: mid-density genome-wide association genetics and diversity patterns reveal key genomic regions, with a major contribution of the Vgt2 (ZCN8 locus.

Directory of Open Access Journals (Sweden)

Sophie Bouchet

Full Text Available The migration of maize from tropical to temperate climates was accompanied by a dramatic evolution in flowering time. To gain insight into the genetic architecture of this adaptive trait, we conducted a 50K SNP-based genome-wide association and diversity investigation on a panel of tropical and temperate American and European representatives. Eighteen genomic regions were associated with flowering time. The number of early alleles cumulated along these regions was highly correlated with flowering time. Polymorphism in the vicinity of the ZCN8 gene, which is the closest maize homologue to Arabidopsis major flowering time (FT gene, had the strongest effect. This polymorphism is in the vicinity of the causal factor of Vgt2 QTL. Diversity was lower, whereas differentiation and LD were higher for associated loci compared to the rest of the genome, which is consistent with selection acting on flowering time during maize migration. Selection tests also revealed supplementary loci that were highly differentiated among groups and not associated with flowering time in our panel, whereas they were in other linkage-based studies. This suggests that allele fixation led to a lack of statistical power when structure and relatedness were taken into account in a linear mixed model. Complementary designs and analysis methods are necessary to unravel the architecture of complex traits. Based on linkage disequilibrium (LD estimates corrected for population structure, we concluded that the number of SNPs genotyped should be at least doubled to capture all QTLs contributing to the genetic architecture of polygenic traits in this panel. These results show that maize flowering time is controlled by numerous QTLs of small additive effect and that strong polygenic selection occurred under cool climatic conditions. They should contribute to more efficient genomic predictions of flowering time and facilitate the dissemination of diverse maize genetic resources under a wide

Beneficial Effects of Temperate Forage Legumes that Contain Condensed Tannins

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Jennifer W. MacAdam

2015-07-01

Full Text Available The two temperate forage legumes containing condensed tannins (CT that promote ruminant production are birdsfoot trefoil (Lotus corniculatus L.; BFT and sainfoin (Onobrychis viciifolia Scop.; SF. Both are well-adapted to the cool-temperate climate and alkaline soils of the Mountain West USA. Condensed tannins comprise a diverse family of bioactive chemicals with multiple beneficial functions for ruminants, including suppression of internal parasites and enteric methane. Birdsfoot trefoil contains 10 to 40 g·CT·kg−1 dry matter (DM, while SF contains 30 to 80 g·CT·kg−1 DM. Our studies have focused on these two plant species and have demonstrated consistently elevated rates of gain for beef calves grazing both BFT and SF. Novel results from our BFT research include carcass dressing percentages and consumer sensory evaluations equivalent to feedlot-finished steers and significantly greater than grass-finished steers, but with omega-3 fatty acid concentrations equal to grass-finished beef. We have further demonstrated that ruminants fed BFT or SF will consume more endophyte-infected tall fescue (Schedonorus arundinaceus (Schreb. Dumort. forage or seed than ruminants fed a non-CT forage legume. There is great potential value for sustainable livestock production in the use of highly digestible, nitrogen-fixing legumes containing tannins demonstrated to improve ruminant productivity.

Temperate marine protected area provides recruitment subsidies to local fisheries.

Science.gov (United States)

Le Port, A; Montgomery, J C; Smith, A N H; Croucher, A E; McLeod, I M; Lavery, S D

2017-10-25

The utility of marine protected areas (MPAs) as a means of protecting exploited species and conserving biodiversity within MPA boundaries is supported by strong empirical evidence. However, the potential contribution of MPAs to fished populations beyond their boundaries is still highly controversial; empirical measures are scarce and modelling studies have produced a range of predictions, including both positive and negative effects. Using a combination of genetic parentage and relatedness analysis, we measured larval subsidies to local fisheries replenishment for Australasian snapper ( Chrysophrys auratus : Sparidae) from a small (5.2 km 2 ), well-established, temperate, coastal MPA in northern New Zealand. Adult snapper within the MPA contributed an estimated 10.6% (95% CI: 5.5-18.1%) of newly settled juveniles to surrounding areas (approx. 400 km 2 ), with no decreasing trend in contributions up to 40 km away. Biophysical modelling of larval dispersal matched experimental data, showing larvae produced inside the MPA dispersed over a comparable distance. These results demonstrate that temperate MPAs have the potential to provide recruitment subsidies at magnitudes and spatial scales relevant to fisheries management. The validated biophysical model provides a cost-efficient opportunity to generalize these findings to other locations and climate conditions, and potentially informs the design of MPA networks for enhancing fisheries management. © 2017 The Author(s).

Climate and Vegetation Effects on Temperate Mountain Forest ...

Science.gov (United States)

Current forest composition may be resilient to typical climatic variability; however, climate trends, combined with projected changes in species composition, may increase tree vulnerability to water stress. A shift in forest composition toward tree species with higher water use has implications for biogenic emissions and deposition of reactive nitrogen and carbon compounds. Forest evapotranspiration (ET) can vary greatly at daily and seasonal time scales, but compared to carbon fluxes, often exhibits relatively consistent inter-annual behavior. The processes controlling ET involve the combined effects of physical and biological factors. Atmospheric conditions that promote high ET, consisting of high radiation and vapor pressure deficit (D), are often characterized by rainless periods when soil water supply to vegetation may be limiting and plant stomata may close to prevent excessive water loss. In contrast, periods of high ecosystem water availability require frequent precipitation and are characterized by low D. Thus, the combination of these contrasting conditions throughout a growing season may explain some of the consistency in ET. Additionally, vegetation composition is also an important factor in determining ET. In mixed species forests, physiological differences in water use strategies (e.g. isohydric/anisohydric species) can produce conservative water use throughout wet and dry phases of the growing season. Furthermore, transpiration by evergreen specie

GIS development to monitor climate change and its geohydrological consequences on non-monsoon crop pattern in Himalaya

Science.gov (United States)

Rawat, Pradeep K.

2014-09-01

The main objective of the study was to assess climate change and its geohydrological impacts on non-monsoon crop pattern at watershed level through GIS development on climate informatics, land use informatics, hydro-informatics and agro-informatics. The Dabka watershed constitutes a part of the Kosi Basin in densely populated Lesser Himalaya, India in district Nainital has been selected for the case illustration. This reconnaissance study analyzed the climatic database for last three decades (1982-2012) and estimates that the average temperature and evaporation loss have been rising with the rate of 0.07 °C/yr and 4.03 mm/yr respectively whereas the average rainfall has been decreasing with the rate of 0.60 mm/yr. These rates of climate change increasing with mounting elevations. Consequently the existing microclimatic zones (sub-tropical, temperate and moist temperate) shifting towards higher altitudes and affecting the favorable conditions of the land use pattern and decreased the eco-friendly forest and vegetation cover. The land use degradation and high rate of deforestation (0.22 km2 or 1.5%/yr) leads to accelerate several hydrological problems during non-monsoon period (i.e. decreasing infiltration capacity of land surface, declining underground water level, drying up natural perennial springs and streams, decreasing irrigation water availability etc.). In order to that the non-monsoon crops yield has been decreasing with the rate of 0.60% each year as the results suggest that the average crop yield is just about 58 q/ha whereas twenty five to thirty year back it was recorded about 66 q/ha which is about 12% higher (8 q/ha) than existing yield. On the other hand the population increasing with the growth rate of 2% each year. Therefore, decreasing crop yield and increasing population raised food deficiency problem and the people adopting other occupations which ultimately affecting rural livelihood of the Himalaya.

An empirical exploration of the world oil price under the target zone model

International Nuclear Information System (INIS)

Linghui Tang; Shawkat Hammoudeh

2002-01-01

This paper investigates the behavior of the world oil price based on the first-generation target zone model. Using anecdotal data during the period of 1988-1999, we found that OPEC has tried to maintain a weak target zone regime for the oil price. Our econometric tests suggest that the movement of the oil price is not only manipulated by actual and substantial interventions by OPEC but also tempered by market participants' expectations of interventions. As a consequence, the non-linear model based on the target zone theory has very good forecasting ability when the oil price approaches the upper or lower limit of the band. (author)

An empirical exploration of the world oil price under the target zone model

International Nuclear Information System (INIS)

Tang, Linghui; Hammoudeh, Shawkat

2002-01-01

This paper investigates the behavior of the world oil price based on the first-generation target zone model. Using anecdotal data during the period of 1988-1999, we found that OPEC has tried to maintain a weak target zone regime for the oil price. Our econometric tests suggest that the movement of the oil price is not only manipulated by actual and substantial interventions by OPEC but also tempered by market participants' expectations of interventions. As a consequence, the non-linear model based on the target zone theory has very good forecasting ability when the oil price approaches the upper or lower limit of the band

Precipitation variability in the winter rainfall zone of South Africa during the last 1400 yr linked to the austral westerlies

Directory of Open Access Journals (Sweden)

J. C. Stager

2012-05-01

Full Text Available The austral westerlies strongly influence precipitation and ocean circulation in the southern temperate zone, with important consequences for cultures and ecosystems. Global climate models anticipate poleward retreat of the austral westerlies with future warming, but the available paleoclimate records that might test these models have been limited to South America and New Zealand, are not fully consistent with each other and may be complicated by influences from other climatic factors. Here we present the first high-resolution diatom and sedimentological records from the winter rainfall region of South Africa, representing precipitation in the equatorward margin of the westerly wind belt during the last 1400 yr. Inferred rainfall was relatively high ∼1400–1200 cal yr BP, decreased until ∼950 cal yr BP, and rose notably through the Little Ice Age with pulses centred on ∼600, 530, 470, 330, 200, 90, and 20 cal yr BP. Synchronous fluctuations in Antarctic ice core chemistry strongly suggest that these variations were linked to changes in the westerlies. Equatorward drift of the westerlies during the wet periods may have influenced Atlantic meridional overturning circulation by restricting marine flow around the tip of Africa. Apparent inconsistencies among some aspects of records from South America, New Zealand and South Africa warn against the simplistic application of single records to the Southern Hemisphere as a whole. Nonetheless, these findings in general do support model projections of increasing aridity in the austral winter rainfall zones with future warming.

Thermal sensitivity of the crab Neosarmatium africanum in tropical and temperate mangroves on the east coast of Africa

KAUST Repository

Fusi, Marco

2017-03-09

Mangrove forests are amongst the tropical marine ecosystems most severely affected by rapid environmental change, and the activities of key associated macrobenthic species contribute to their ecological resilience. Along the east coast of Africa, the amphibious sesarmid crab Neosarmatium africanum (=meinerti) plays a pivotal role in mangrove ecosystem functioning through carbon cycling and sediment bioturbation. In the face of rapid climate change, identifying the sensitivity and vulnerability to global warming of this species is of increasing importance. Based on a latitudinal comparison, we measured the thermal sensitivity of a tropical and a temperate population of N. africanum, testing specimens at the centre and southern limit of its distribution, respectively. We measured metabolic oxygen consumption and haemolymph dissolved oxygen content during air and water breathing within a temperature range that matched the natural environmental conditions. The results indicate different thermal sensitivities in the physiological responses of N. africanum from tropical and temperate populations, especially during air breathing. The differences observed in the thermal physiology between the two populations suggest that the effect of global warming on this important mangrove species may be different under different climate regimes.

Contributions of hydroclimate variability and associated North-African riverine fluxes to eastern-Mediterranean sapropel formation and related seawater circulation

NARCIS (Netherlands)

Wu, Jiawang

2017-01-01

The Mediterranean Sea is a semi-enclosed basin surrounded by catchment areas characterized by different climate regimes, as it lies at the interface between the African tropical and European temperate zones. Moreover, the Mediterranean has a dynamic thermohaline circulation, making it particularly

Cerebral absces med Vibrio cholerae non-01 efter badning i dansk havvand

DEFF Research Database (Denmark)

Torp-Pedersen, Trine; Nielsen, Xiaohui Chen; Olsen, Katharina E P

2012-01-01

on the ankle. We treated the patient with meropenem and ciprofloxacin for six weeks followed by ciprofloxacin for four weeks, and she recovered with hemiparesis and speech impairment. Marine Vibrio species may produce intracranial infection in predisposed individuals, even in temperate climate zones....

Effects of the age class distributions of the temperate and boreal forests on the global CO2 source-sink function

Science.gov (United States)

Kohlmaier, G. H.; Häger, Ch.; Würth, G.; Lüdeke, M. K. B.; Ramge, P.; Badeck, F.-W.; Kindermann, J.; Lang, T.

1995-02-01

The rôle of the temperate and boreal forests as a global CO2 source or sink is examined, both for the present time and for the next hundred years. The results of the Forest Resource Assessment for 1990 of the Economic Comission for Europe and the Food and Agricultural Organisation of the United Nations (1992) serve as the main database in this study. Out of the estimated total area of approximately 20106 km2 of forests and wooded lands in the temperate and boreal zone only approximately fifty percent is documented within the category of exploitable forests, which are examined in detail here. In this study, a general formalism of the time evolution of an ensemble of forests within an ecological province is developed using the formalism of the Leslie matrix. This matrix can be formulated if the age class dependent mortalities which arise from the disturbances are known. A distinction is made between the natural disturbances by fire, wind throw and insect infestations and disturbances introduced through harvesting of timber. Through the use of Richards growth function each age class of a given biome is related to the corresponding biomass and annual increment. The data reported on the mean net annual increment and on the mean biomass serve to calibrate the model. The difference of the reported net annual increment and annual fellings of approximately 550 106 m3 roundwood correspond to a sink of 210-330 Mt of carbon per year excluding any changes in the soil balance. It could be shown that the present distribution of forest age classes for the United States, Canada, Europe, or the former Soviet Union does not correspond to a quasi-stationary state, in which biomass is accumulated only due to a stimulated growth under enhanced atmospheric CO2 levels. The present CO2 sink function will not persist in the next century, if harvesting rates increase with 0.5% annually or even less. The future state will also be influenced by the effect of the greenhouse climate, the impact

Assessing the potential risk of Zika virus epidemics in temperate areas with established Aedes albopictus populations.

Science.gov (United States)

Guzzetta, Giorgio; Poletti, Piero; Montarsi, Fabrizio; Baldacchino, Frederic; Capelli, Gioia; Rizzoli, Annapaola; Rosà, Roberto; Merler, Stefano

2016-04-14

Based on 2015 abundance of Aedes albopictus in nine northern Italian municipalities with temperate continental/oceanic climate, we estimated the basic reproductive number R0 for Zika virus (ZIKV) to be systematically below the epidemic threshold in most scenarios. Results were sensitive to the value of the probability of mosquito infection after biting a viraemic host. Therefore, further studies are required to improve models and predictions, namely evaluating vector competence and potential non-vector transmissions.

Cold-climate slope deposits and landscape modifications of the Mid-Atlantic Coastal Plain, Eastern USA

Science.gov (United States)

Newell, Wayne L.; Dejong, B.D.

2011-01-01

The effects of Pleistocene cold-climate geomorphology are distributed across the weathered and eroded Mid-Atlantic Coastal Plain uplands from the Wisconsinan terminal moraine south to Tidewater Virginia. Cold-climate deposits and landscape modifications are superimposed on antecedent landscapes of old, weathered Neogene upland gravels and Pleistocene marine terraces that had been built during warm periods and sea-level highstands. In New Jersey, sequences of surficial deposits define a long history of repeating climate change events. To the south across the Delmarva Peninsula and southern Maryland, most antecedent topography has been obscured by Late Pleistocene surficial deposits. These are spatially variable and are collectively described as a cold-climate alloformation. The cold-climate alloformation includes time-transgressive details of climate deterioration from at least marine isotope stage (MIS) 4 through the end of MIS 2. Some deposits and landforms within the alloformation may be as young as the Younger Dryas. Southwards along the trend of the Potomac River, these deposits and their climatic affinities become diffused. In Virginia, a continuum of erosion and surficial deposits appears to be the product of ‘normal’ temperate, climate-forced processes. The cold-climate alloformation and more temperate deposits in Virginia are being partly covered by Holocene alluvium and bay mud.

Land Surface Temperature Differences within Local Climate Zones, Based on Two Central European Cities

Czech Academy of Sciences Publication Activity Database

Geletič, Jan; Lehnert, M.; Dobrovolný, Petr

2016-01-01

Roč. 8, č. 10 (2016), č. článku 788. ISSN 2072-4292 R&D Projects: GA MŠk(CZ) LO1415 Grant - others:UrbanAdapt(XE) EHP-CZ02-OV-1-036-2015 Program:CZ02 Biodiverzita a ekosystémové služby / Monitorování a integrované plánování a kontrola v životním prostředí/ Adaptace na změnu klimatu Institutional support: RVO:67179843 Keywords : land surface temperature * local climate zones * ASTER * LANDSAT * analysis of variance * Prague * Brno * Czech Republic Subject RIV: EH - Ecology, Behaviour Impact factor: 3.244, year: 2016

The responses of microbial temperature relationships to seasonal change and winter warming in a temperate grassland.

Science.gov (United States)

Birgander, Johanna; Olsson, Pål Axel; Rousk, Johannes

2018-01-18

Microorganisms dominate the decomposition of organic matter and their activities are strongly influenced by temperature. As the carbon (C) flux from soil to the atmosphere due to microbial activity is substantial, understanding temperature relationships of microbial processes is critical. It has been shown that microbial temperature relationships in soil correlate with the climate, and microorganisms in field experiments become more warm-tolerant in response to chronic warming. It is also known that microbial temperature relationships reflect the seasons in aquatic ecosystems, but to date this has not been investigated in soil. Although climate change predictions suggest that temperatures will be mostly affected during winter in temperate ecosystems, no assessments exist of the responses of microbial temperature relationships to winter warming. We investigated the responses of the temperature relationships of bacterial growth, fungal growth, and respiration in a temperate grassland to seasonal change, and to 2 years' winter warming. The warming treatments increased winter soil temperatures by 5-6°C, corresponding to 3°C warming of the mean annual temperature. Microbial temperature relationships and temperature sensitivities (Q 10 ) could be accurately established, but did not respond to winter warming or to seasonal temperature change, despite significant shifts in the microbial community structure. The lack of response to winter warming that we demonstrate, and the strong response to chronic warming treatments previously shown, together suggest that it is the peak annual soil temperature that influences the microbial temperature relationships, and that temperatures during colder seasons will have little impact. Thus, mean annual temperatures are poor predictors for microbial temperature relationships. Instead, the intensity of summer heat-spells in temperate systems is likely to shape the microbial temperature relationships that govern the soil-atmosphere C

Comparative transcriptome analysis of ginger variety Suprabha from two different agro-climatic zones of Odisha.

Science.gov (United States)

Gaur, Mahendra; Das, Aradhana; Sahoo, Rajesh Kumar; Mohanty, Sujata; Joshi, Raj Kumar; Subudhi, Enketeswara

2016-09-01

Ginger (Zingiber officinale Rosc.), a well-known member of family Zingiberaceae, is bestowed with number of medicinal properties which is because of the secondary metabolites, essential oil and oleoresin, it contains in its rhizome. The drug yielding potential is known to depend on agro-climatic conditions prevailing at the place cultivation. Present study deals with comparative transcriptome analysis of two sample of elite ginger variety Suprabha collected from two different agro-climatic zones of Odisha. Transcriptome assembly for both the samples was done using next generation sequencing methodology. The raw data of size 10.8 and 11.8 GB obtained from analysis of two rhizomes S1Z4 and S2Z5 collected from Bhubaneswar and Koraput and are available in NCBI accession number SAMN03761169 and SAMN03761176 respectively. We identified 60,452 and 54,748 transcripts using trinity tool respectively from ginger rhizome of S1Z4 and S2Z5. The transcript length varied from 300 bp to 15,213 bp and 8988 bp and N50 value of 1415 bp and 1334 bp respectively for S1Z4 and S2Z5. To the best of our knowledge, this is the first comparative transcriptome analysis of elite ginger cultivars Suprabha from two different agro-climatic conditions of Odisha, India which will help to understand the effect of agro-climatic conditions on differential expression of secondary metabolites.

Well-Tempered Metadynamics Converges Asymptotically

Science.gov (United States)

Dama, James F.; Parrinello, Michele; Voth, Gregory A.

2014-06-01

Metadynamics is a versatile and capable enhanced sampling method for the computational study of soft matter materials and biomolecular systems. However, over a decade of application and several attempts to give this adaptive umbrella sampling method a firm theoretical grounding prove that a rigorous convergence analysis is elusive. This Letter describes such an analysis, demonstrating that well-tempered metadynamics converges to the final state it was designed to reach and, therefore, that the simple formulas currently used to interpret the final converged state of tempered metadynamics are correct and exact. The results do not rely on any assumption that the collective variable dynamics are effectively Brownian or any idealizations of the hill deposition function; instead, they suggest new, more permissive criteria for the method to be well behaved. The results apply to tempered metadynamics with or without adaptive Gaussians or boundary corrections and whether the bias is stored approximately on a grid or exactly.

Natural and traditional defense mechanisms to reduce climate risks in coastal zones of Bangladesh

Directory of Open Access Journals (Sweden)

Mohammed Ataur Rahman

2015-03-01

possible to reduce the effects of natural and climate change-induced disasters. Under such a management system, the entire coastal zone can be made more productive and sustainable.

Effect of thermal tempering on microstructure and mechanical properties of Mg-AZ31/Al-6061 diffusion bonding

Energy Technology Data Exchange (ETDEWEB)

Jafarian, Mojtaba [Young Researchers and Elite Club, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Rizi, Mohsen Saboktakin, E-mail: M.saboktakin@Pa.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111 (Iran, Islamic Republic of); Department of Industrial Engineering, Lenjan Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Jafarian, Morteza [Young Researchers and Elite Club, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Honarmand, Mehrdad [Department of Mechanical Engineering, Tiran Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Javadinejad, Hamid Reza; Ghaheri, Ali [Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111 (Iran, Islamic Republic of); Department of Industrial Engineering, Lenjan Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Bahramipour, Mohammad Taghi [Materials Engineering Department, Hakim Sabzevari University, Sabzevar, 397 (Iran, Islamic Republic of); Ebrahimian, Marzieh [Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111 (Iran, Islamic Republic of); Department of Industrial Engineering, Lenjan Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of)

2016-06-01

The objective of this study is to investigate the effect of the types thermal tempering of aluminum alloy on microstructure and mechanical properties of AZ31-O Mg and Al 6061-T6 diffusion bonding. Using Optical Microscope (OM) and Scanning Electron Microscopes (SEM) equipped with EDS analysis and line scan the interfaces of joints were evaluated. The XRD analysis was carried out to characterize phase constitution near the interface zone. The mechanical properties of joints were measured using Vickers micro-hardness and shear strength. According to the results in bonding of AZ31-Mg/Al-6061-O, in less plastic deformation in magnesium alloy, diffusion rate of most magnesium atoms occurred to aluminum alloy and formation of diffusion zone with minimum micro-hardness (140 HV) and maximum shear strength (32 MPa) compared to Al 6061-T6/Mg-AZ31 bonding. Evaluation of fracture surfaces indicates an occurrence of failure from the brittle intermetallic phases. - Highlights: • Diffusion bonding AZ31 to Al-6061withoutany interlayer was successful. • Thermal tempered aluminum alloy plays a vital role in the mechanical properties of joint. • Less thickness of reaction layers and micro-hardness in bonding annealed Al- 6061 layers to AZ31 was achieved. • Fracture surfaces indicated that the onset of fracture from intermetallic compounds resulted in fracture of the cleavage.

Effect of thermal tempering on microstructure and mechanical properties of Mg-AZ31/Al-6061 diffusion bonding

International Nuclear Information System (INIS)

Jafarian, Mojtaba; Rizi, Mohsen Saboktakin; Jafarian, Morteza; Honarmand, Mehrdad; Javadinejad, Hamid Reza; Ghaheri, Ali; Bahramipour, Mohammad Taghi; Ebrahimian, Marzieh

2016-01-01

The objective of this study is to investigate the effect of the types thermal tempering of aluminum alloy on microstructure and mechanical properties of AZ31-O Mg and Al 6061-T6 diffusion bonding. Using Optical Microscope (OM) and Scanning Electron Microscopes (SEM) equipped with EDS analysis and line scan the interfaces of joints were evaluated. The XRD analysis was carried out to characterize phase constitution near the interface zone. The mechanical properties of joints were measured using Vickers micro-hardness and shear strength. According to the results in bonding of AZ31-Mg/Al-6061-O, in less plastic deformation in magnesium alloy, diffusion rate of most magnesium atoms occurred to aluminum alloy and formation of diffusion zone with minimum micro-hardness (140 HV) and maximum shear strength (32 MPa) compared to Al 6061-T6/Mg-AZ31 bonding. Evaluation of fracture surfaces indicates an occurrence of failure from the brittle intermetallic phases. - Highlights: • Diffusion bonding AZ31 to Al-6061withoutany interlayer was successful. • Thermal tempered aluminum alloy plays a vital role in the mechanical properties of joint. • Less thickness of reaction layers and micro-hardness in bonding annealed Al- 6061 layers to AZ31 was achieved. • Fracture surfaces indicated that the onset of fracture from intermetallic compounds resulted in fracture of the cleavage.

Die Nephrotoma-Verbreitung in der Welt (Diptera, Tipulidae)

NARCIS (Netherlands)

Oosterbroek, P.; Schuckard, R.; Theowald, B.

1976-01-01

The distributional patterns of the members of the genus Nephrotoma have been analyzed. Most species prefer moist temperate climates, thus showing a correlation with the zone of deciduous forests. Almost all species of the southern hemisphere occupy strongly restricted areas in mountain forests, but

The evolution of Holocene coastal dunefields, Jutland, Denmark

DEFF Research Database (Denmark)

Clemmensen, Lars B; Murray, Andrew S.; Heinemeier, Jan

2009-01-01

Coastal dunefields have developed on the west coast of Jutland in Denmark over the past 5000 years. The dunefields are situated in a temperate climate zone with frequent high energy wind events. Dunefield development was characterized by repeated periods of transgressive dune formation punctuated...

Meeting wild bees' needs on rangelands

Science.gov (United States)

Some arid rangeland regions, notably those with warm dry climates of the temperate zones, host great diversities of native bees, primarily non-social species among which are many floral specialists. Rangeland bee faunas are threatened indirectly by invasive exotic weeds wherever these displace nat...

Agriculture in the Fertile Crescent: Continuity and change under climate change

Science.gov (United States)

The Fertile Crescent is a highly biodiverse region where most temperate-zone agricultural species originated and were first domesticated. A favorable environment, a special plant community, and an adaptive population combined to initiate the transition from a hunter-gatherer economy to one based on ...

Responses of Terrestrial Ecosystems’ Net Primary Productivity to Future Regional Climate Change in China

Science.gov (United States)

Zhao, Dongsheng; Wu, Shaohong; Yin, Yunhe

2013-01-01

The impact of regional climate change on net primary productivity (NPP) is an important aspect in the study of ecosystems’ response to global climate change. China’s ecosystems are very sensitive to climate change owing to the influence of the East Asian monsoon. The Lund–Potsdam–Jena Dynamic Global Vegetation Model for China (LPJ-CN), a global dynamical vegetation model developed for China’s terrestrial ecosystems, was applied in this study to simulate the NPP changes affected by future climate change. As the LPJ-CN model is based on natural vegetation, the simulation in this study did not consider the influence of anthropogenic activities. Results suggest that future climate change would have adverse effects on natural ecosystems, with NPP tending to decrease in eastern China, particularly in the temperate and warm temperate regions. NPP would increase in western China, with a concentration in the Tibetan Plateau and the northwest arid regions. The increasing trend in NPP in western China and the decreasing trend in eastern China would be further enhanced by the warming climate. The spatial distribution of NPP, which declines from the southeast coast to the northwest inland, would have minimal variation under scenarios of climate change. PMID:23593325

Temperature reconstruction from dripwater hydrochemistry, speleothem fabric and speleothem δ13C: towards an integrated approach in temperate climate caves

Science.gov (United States)

Borsato, Andrea; Frisia, Silvia; Johnston, Vanessa; Spötl, Christoph

2017-04-01

Accurate reconstruction of past climate records from speleothem minerals requires a thorough understanding of both environmental and hydrologic conditions underpinning their formation. These conditions likely influenced how speleothems incorporate chemical signals that are used as climate proxies. Thus, a thorough investigation of environmental and hydrologic parameters is a pre-requisite to gain robust palaeoclimate reconstructions from stalagmites. Here, we present a systematic study of soil, dripwater and speleothems in temperate climate caves at different altitudes, which allowed the assessment of how mean annual air temperature in the infiltration area (MATinf) influences vegetation cover, soil pCO2 and, eventually, pCO2 of karst water and cave air. Our study demonstrates that for caves developed in pure carbonate rocks, the soil and aquifer pCO2 are directly related to the MATinf (Borsato et al., 2015). It is well known that soil and aquifer pCO2 control carbonate dissolution and the carbonate-carbonic acid system. By establishing a relationship between dripwater pCO2 and MATinf, we show that dripwater Ca content and calcite saturation state SIcc) are correlated with MATinf when unaffected by Prior Calcite Precipitation. In particular, dripwater saturation (SIcc = 0) is reached at a MATinf of 4.4°C in our study area. This MATinf delineates a ''speleothem limit", above which speleothems composed of sparitic calcite should not form (Borsato et al., 2016). In fact, sparitic calcite speleothems do not form, today, in caves with a MATinf well as calcite δ13C in speleothems that were not significantly influenced by kinetic fractionation. A linear correlation between calcite δ13C and MATinf was obtained for modern sparitic speleothems that formed at isotopic equilibrium (Johnston et al., 2013). The combination of these two approaches (present-day dripwater SIcc and calcite δ13C in sparitic speleothems) can be used to reconstruct the past MATinf for high

Projecting the Global Distribution of the Emerging Amphibian Fungal Pathogen, Batrachochytrium dendrobatidis, Based on IPCC Climate Futures.

Directory of Open Access Journals (Sweden)

Gisselle Yang Xie

Full Text Available Projected changes in climate conditions are emerging as significant risk factors to numerous species, affecting habitat conditions and community interactions. Projections suggest species range shifts in response to climate change modifying environmental suitability and is supported by observational evidence. Both pathogens and their hosts can shift ranges with climate change. We consider how climate change may influence the distribution of the emerging infectious amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd, a pathogen associated with worldwide amphibian population losses. Using an expanded global Bd database and a novel modeling approach, we examined a broad set of climate metrics to model the Bd-climate niche globally and regionally, then project how climate change may influence Bd distributions. Previous research showed that Bd distribution is dependent on climatic variables, in particular temperature. We trained a machine-learning model (random forest with the most comprehensive global compilation of Bd sampling records (~5,000 site-level records, mid-2014 summary, including 13 climatic variables. We projected future Bd environmental suitability under IPCC scenarios. The learning model was trained with combined worldwide data (non-region specific and also separately per region (region-specific. One goal of our study was to estimate of how Bd spatial risks may change under climate change based on the best available data. Our models supported differences in Bd-climate relationships among geographic regions. We projected that Bd ranges will shift into higher latitudes and altitudes due to increased environmental suitability in those regions under predicted climate change. Specifically, our model showed a broad expansion of areas environmentally suitable for establishment of Bd on amphibian hosts in the temperate zones of the Northern Hemisphere. Our projections are useful for the development of monitoring designs in these areas

Shallow aquifer response to climate change scenarios in a small catchment in the Guarani Aquifer outcrop zone.

Science.gov (United States)

Melo, Davi C D; Wendland, Edson

2017-05-01

Water availability restrictions are already a reality in several countries. This issue is likely to worsen due to climate change, predicted for the upcoming decades. This study aims to estimate the impacts of climate change on groundwater system in the Guarani Aquifer outcrop zone. Global Climate Models (GCM) outputs were used as inputs to a water balance model, which produced recharge estimates for the groundwater model. Recharge was estimated across different land use types considering a control period from 2004 to 2014, and a future period from 2081 to 2099. Major changes in monthly rainfall means are expected to take place in dry seasons. Most of the analysed scenarios predict increase of more than 2 ºC in monthly mean temperatures. Comparing the control and future runs, our results showed a mean recharge change among scenarios that ranged from ~-80 to ~+60%, depending on the land use type. As a result of such decrease in recharge rates, the response given by the groundwater model indicates a lowering of the water table under most scenarios.

Mortality during a Large-Scale Heat Wave by Place, Demographic Group, Internal and External Causes of Death, and Building Climate Zone.

Science.gov (United States)

Joe, Lauren; Hoshiko, Sumi; Dobraca, Dina; Jackson, Rebecca; Smorodinsky, Svetlana; Smith, Daniel; Harnly, Martha

2016-03-09

Mortality increases during periods of elevated heat. Identification of vulnerable subgroups by demographics, causes of death, and geographic regions, including deaths occurring at home, is needed to inform public health prevention efforts. We calculated mortality relative risks (RRs) and excess deaths associated with a large-scale California heat wave in 2006, comparing deaths during the heat wave with reference days. For total (all-place) and at-home mortality, we examined risks by demographic factors, internal and external causes of death, and building climate zones. During the heat wave, 582 excess deaths occurred, a 5% increase over expected (RR = 1.05, 95% confidence interval (CI) 1.03-1.08). Sixty-six percent of excess deaths were at home (RR = 1.12, CI 1.07-1.16). Total mortality risk was higher among those aged 35-44 years than ≥ 65, and among Hispanics than whites. Deaths from external causes increased more sharply (RR = 1.18, CI 1.10-1.27) than from internal causes (RR = 1.04, CI 1.02-1.07). Geographically, risk varied by building climate zone; the highest risks of at-home death occurred in the northernmost coastal zone (RR = 1.58, CI 1.01-2.48) and the southernmost zone of California's Central Valley (RR = 1.43, CI 1.21-1.68). Heat wave mortality risk varied across subpopulations, and some patterns of vulnerability differed from those previously identified. Public health efforts should also address at-home mortality, non-elderly adults, external causes, and at-risk geographic regions.

Development of passive design zones in China using bioclimatic approach

International Nuclear Information System (INIS)

Lam, Joseph C.; Yang Liu; Liu Jiaping

2006-01-01

This paper presents the work on development of passive design zones for different climates in China. A total of 18 cities representing the five major climatic types, namely severe cold, cold, hot summer and cold winter, mild and hot summer and warm winter were selected for climatic analysis. Measured weather data were gathered and analysed. A bioclimatic approach was adopted in which the comfort zone and 12 monthly climatic lines were determined and plotted on the psychrometric chart for each city. From these bioclimatic charts, the potential use of passive design strategies such as solar heating, natural ventilation, thermal mass with/without night ventilation and evaporative cooling was assessed. A total of nine passive design strategy zones were identified, and appropriate design strategies suggested for both summer and winter consideration