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Global Change (global + change)
Terms modified by Global Change Selected AbstractsThe UN System and Religious Actors in the Context of Global ChangeCROSSCURRENTS, Issue 3 2010Josef Boehle First page of article [source] People Management in the Context of Global ChangeEMPLOYMENT RELATIONS TODAY, Issue 2 2002Shirley Chan First page of article [source] Teaching and Learning Guide for: The Geopolitics of Climate ChangeGEOGRAPHY COMPASS (ELECTRONIC), Issue 5 2008Jon Barnett Author's Introduction Climate change is a security problem in as much as the kinds of environmental changes that may result pose risks to peace and development. However, responsibilities for the causes of climate change, vulnerability to its effects, and capacity to solve the problem, are not equally distributed between countries, classes and cultures. There is no uniformity in the geopolitics of climate change, and this impedes solutions. Author Recommends 1.,Adger, W. N., et al. (eds) (2006). Fairness in adaptation to climate change. Cambridge, MA: MIT Press. A comprehensive collection of articles on the justice dimensions of adaptation to climate change. Chapters discuss potential points at which climate change becomes ,dangerous', the issue of adaptation under the United Nations Framework Convention on Climate Change (UNFCCC), the unequal outcomes of adaptation within a society, the effects of violent conflict on adaptation, the costs of adaptation, and examples from Bangladesh, Tanzania, Botswana, and Hungary. 2.,Leichenko, R., and O'Brien, K. (2008). Environmental change and globalization: double exposures. New York: Oxford University Press. This book uses examples from around the world to show the way global economic and political processes interact with environmental changes to create unequal outcomes within and across societies. A very clear demonstration of the way vulnerability to environmental change is as much driven by social processes as environmental ones, and how solutions lie within the realm of decisions about ,development' and ,environment'. 3.,Nordås, R., and Gleditsch, N. (2007). Climate conflict: common sense or nonsense? Political Geography 26 (6), pp. 627,638. doi:10.1016/j.polgeo.2007.06.003 An up-to-date, systematic and balanced review of research on the links between climate change and violent conflict. See also the other papers in this special issue of Political Geography. 4.,Parry, M., et al. (eds) (2007). Climate change 2007: impacts adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the intergovernmental panel on climate change. Cambridge, UK: Cambridge University Press. The definitive review of all the peer-reviewed research on the way climate change may impact on places and sectors across the world. Includes chapters on ecosystems, health, human settlements, primary industries, water resources, and the major regions of the world. All chapters are available online at http://www.ipcc.ch/ipccreports/ar4-wg2.htm 5.,Salehyan, I. (2008). From climate change to conflict? No consensus yet. Journal of Peace Research 45 (3), pp. 315,326. doi:10.1177/0022343308088812 A balanced review of research on the links between climate change and conflict, with attention to existing evidence. 6.,Schwartz, P., and Randall, D. (2003). An abrupt climate change scenario and its implications for United States national security. San Francisco, CA: Global Business Network. Gives insight into how the US security policy community is framing the problem of climate change. This needs to be read critically. Available at http://www.gbn.com/ArticleDisplayServlet.srv?aid=26231 7.,German Advisory Council on Global Change. (2007). World in transition: climate change as a security risk. Berlin, Germany: WBGU. A major report from the German Advisory Council on Global Change on the risks climate changes poses to peace and stability. Needs to be read with caution. Summary and background studies are available online at http://www.wbgu.de/wbgu_jg2007_engl.html 8.,Yamin, F., and Depedge, J. (2004). The International climate change regime: a guide to rules, institutions and procedures. Cambridge, UK: Cambridge University Press. A clear and very detailed explanation of the UNFCCC's objectives, actors, history, and challenges. A must read for anyone seeking to understand the UNFCCC process, written by two scholars with practical experience in negotiations. Online Materials 1.,Environmental Change and Security Program at the Woodrow Wilson International Center for Scholars http://www.wilsoncenter.org/ecsp The major website for information about environmental security. From here, you can download many reports and studies, including the Environmental Change and Security Project Report. 2.,Global Environmental Change and Human Security Project http://www.gechs.org This website is a clearing house for work and events on environmental change and human security. 3.,Intergovernmental Panel on Climate Change (IPCC) http://www.ipcc.ch/ From this website, you can download all the chapters of all the IPCC's reports, including its comprehensive and highly influential assessment reports, the most recent of which was published in 2007. The IPCC were awarded of the Nobel Peace Prize ,for their efforts to build up and disseminate greater knowledge about man-made (sic) climate change, and to lay the foundations for the measures that are needed to counteract such change'. 4.,Tyndall Centre for Climate Change Research http://www.tyndall.ac.uk The website of a major centre for research on climate change, and probably the world's leading centre for social science based analysis of climate change. From this site, you can download many publications about mitigation of and adaptation to climate change, and about various issues in the UNFCCC. 5.,United Nations Framework Convention on Climate Change http://unfccc.int/ The website contains every major document relation to the UNFCCC and its Kyoto Protocol, including the text of the agreements, national communications, country submissions, negotiated outcomes, and background documents about most key issues. Sample Syllabus: The Geopolitics of Climate Change topics for lecture and discussion Week I: Introduction Barnett, J. (2007). The geopolitics of climate change. Geography Compass 1 (6), pp. 1361,1375. United Nations Secretary General, Kofi Annan, address to the 12th Conference of Parties to the United Nations Framework Convention on Climate Change, Nairobi, 15 November 2006. Available online at http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=495&ArticleID=5424&l=en Week II: The History and Geography of Greenhouse Gas Emissions Topic: The drivers of climate change in space and time Reading Baer, P. (2006). Adaptation: who pays whom? In: Adger, N., et al. (eds) Fairness in adaptation to climate change. Cambridge, MA: MIT Press, pp. 131,154. Boyden, S., and Dovers, S. (1992). Natural-resource consumption and its environmental impacts in the Western World: impacts of increasing per capita consumption. Ambio 21 (1), pp. 63,69. Week III: The Environmental Consequences of climate change Topic: The risks climate change poses to environmental systems Reading Intergovernmental Panel on Climate Change. (2007). Climate change 2007: climate change impacts, adaptation and vulnerability: summary for policymakers. Geneva, Switzerland: IPCC Secretariat. Watch: Al Gore. The Inconvenient Truth. Weeks IV and V: The Social Consequences of Climate Change Topic: The risks climate change poses to social systems Reading Adger, W. N. (1999). Social vulnerability to climate change and extremes in coastal Vietnam. World Development 27, pp. 249,269. Comrie, A. (2007). Climate change and human health. Geography Compass 1 (3), pp. 325,339. Leary, N., et al. (2006). For whom the bell tolls: vulnerability in a changing climate. A Synthesis from the AIACC project, AIACC Working Paper No. 21, International START Secretariat, Florida. Stern, N. (2007). Economics of climate change: the Stern review. Cambridge, UK: Cambridge University Press (Chapters 3,5). Week VI: Mitigation of Climate Change: The UNFCCC Topic: The UNFCCC and the Kyoto Protocol Reading Najam, A., Huq, S., and Sokona, Y. (2003). Climate negotiations beyond Kyoto: developing countries concerns and interests. Climate Policy 3 (3), pp. 221,231. UNFCCC Secretariat. (2005). Caring for climate: a guide to the climate change convention and the Kyoto Protocol. Bonn, Germany: UN Framework Convention on Climate Change Secretariat. Weeks VII and VIII: Adaptation to Climate Change Topic: What can be done to allow societies to adapt to avoid climate impacts? Reading Adger, N., et al. (2007). Assessment of adaptation practices, options, constraints and capacity. In: Parry, M., et al. (eds) Climate change 2007: impacts, adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the intergovernmental panel on climate change. Cambridge, UK: Cambridge University Press, pp. 717,744. Burton, I., et al. (2002). From impacts assessment to adaptation priorities: the shaping of adaptation policy. Climate Policy 2 (2,3), pp. 145,159. Eakin, H., and Lemos, M. C. (2006). Adaptation and the state: Latin America and the challenge of capacity-building under globalization. Global Environmental Change: Human and Policy Dimensions 16 (1), pp. 7,18. Ziervogel, G., Bharwani, S., and Downing, T. (2006). Adapting to climate variability: pumpkins, people and policy. Natural Resources Forum 30, pp. 294,305. Weeks IX and X: Climate Change and Migration Topic: Will climate change force migration? Readings Gaim, K. (1997). Environmental causes and impact of refugee movements: a critique of the current debate. Disasters 21 (1), pp. 20,38. McLeman, R., and Smit, B. (2006). Migration as adaptation to climate change. Climatic Change 76 (1), pp. 31,53. Myers, N. (2002). Environmental refugees: a growing phenomenon of the 21st century. Philosophical Transactions of the Royal Society 357 (1420), pp. 609,613. Perch-Nielsen, S., Bättig, M., and Imboden, D. (2008). Exploring the link between climate change and migration. Climatic Change (online first, forthcoming); doi:10.1007/s10584-008-9416-y Weeks XI and XII: Climate Change and Violent Conflict Topic: Will Climate change cause violent conflict? Readings Barnett, J., and Adger, N. (2007). Climate change, human security and violent conflict. Political Geography 26 (6), pp. 639,655. Centre for Strategic and International Studies. (2007). The age of consequences: the foreign policy and national security implications of global climate change. Washington, DC: CSIS. Nordås, R., and Gleditsch, N. (2007). Climate conflict: common sense or nonsense? Political Geography 26 (6), pp. 627,638. Schwartz, P., and Randall, D. (2003). An abrupt climate change scenario and its implications for United States national security. San Francisco, CA: Global Business Network. [online]. Retrieved on 8 April 2007 from http://www.gbn.com/ArticleDisplayServlet.srv?aid=26231 Focus Questions 1Who is most responsible for climate change? 2Who is most vulnerable to climate change? 3Does everyone have equal power in the UNFCCC process? 4Will climate change force people to migrate? Who? 5What is the relationship between adaptation to climate change and violent conflict? [source] Erosion models: quality of spatial predictionsHYDROLOGICAL PROCESSES, Issue 5 2003Victor Jetten Abstract An Erratum has been published for this article in Hydrological Processes 18(3) 2004, 595. An overview is given on the predictive quality of spatially distributed runoff and erosion models. A summary is given of the results of model comparison workshops organized by the Global Change and Terrestrial Ecosystems Focus 3 programme, as well as other results obtained by individual researchers. The results concur with the generally held viewpoint in the literature that the predictive quality of distributed models is moderately good for total discharge at the outlet, and not very good for net soil loss. This is only true if extensive calibration is done: uncalibrated results are generally bad. The more simple lumped models seem to perform equally well as the more complex distributed models, although the latter produce more detailed spatially distributed results that can aid the researcher. All these results are outlet based: models are tested on lumped discharge and soil loss or on hydrographs and sedigraphs. Surprisingly few tests have been done on the comparison of simulated and modelled erosion patterns, although this may arguably be just as important in the sense of designing anti-erosion measures and determining source and sink areas. Two studies are shown in which the spatial performance of the erosion model LISEM (Limburg soil erosion model) is analysed. It seems that: (i) the model is very sensitive to the resolution (grid cell size); (ii) the spatial pattern prediction is not very good; (iii) the performance becomes better when the results are resampled to a lower resolution and (iv) the results are improved when certain processes in the model (in this case gully incision) are restricted to so called ,critical areas', selected from the digital elevation model with simple rules. The difficulties associated with calibrating and validating spatially distributed soil erosion models are, to a large extent, due to the large spatial and temporal variability of soil erosion phenomena and the uncertainty associated with the input parameter values used in models to predict these processes. They will, therefore, not be solved by constructing even more complete, and therefore more complex, models. However, the situation may be improved by using more spatial information for model calibration and validation rather than output data only and by using ,optimal' models, describing only the dominant processes operating in a given landscape. Copyright © 2003 John Wiley & Sons, Ltd. [source] Biological Consequences of Global ChangeINTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 2 20104th International Symposium of Intergrative Zoology Kunming, 6 December 2010, China No abstract is available for this article. [source] The Ozone Component of Global Change: Potential Effects on Agricultural and Horticultural Plant Yield, Product Quality and Interactions with Invasive SpeciesJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 4 2009Fitzgerald Booker The productivity, product quality and competitive ability of important agricultural and horticultural plants in many regions of the world may be adversely affected by current and anticipated concentrations of ground-level ozone (O3). Exposure to elevated O3 typically results in suppressed photosynthesis, accelerated senescence, decreased growth and lower yields. Various approaches used to evaluate O3 effects generally concur that current yield losses range from 5% to 15% among sensitive plants. There is, however, considerable genetic variability in plant responses to O3. To illustrate this, we show that ambient O3 concentrations in the eastern United States cause substantially different levels of damage to otherwise similar snap bean cultivars. Largely undesirable effects of O3 can also occur in seed and fruit chemistry as well as in forage nutritive value, with consequences for animal production. Ozone may alter herbicide efficacy and foster establishment of some invasive species. We conclude that current and projected levels of O3 in many regions worldwide are toxic to sensitive plants of agricultural and horticultural significance. Plant breeding that incorporates O3 sensitivity into selection strategies will be increasingly necessary to achieve sustainable production with changing atmospheric composition, while reductions in O3 precursor emissions will likely benefit world food production and reduce atmospheric concentrations of an important greenhouse gas. [source] Transfiguring Capitalism: An Enquiry into Religion and Global Change , By John AthertonRELIGIOUS STUDIES REVIEW, Issue 4 2009Kathryn D. Blanchard No abstract is available for this article. [source] A New Diplomacy for Sustainable Development: The Challenge of Global Change , By Bo KjellénTHE GEOGRAPHICAL JOURNAL, Issue 4 2009Aidan While No abstract is available for this article. [source] Interactions of the Major Biogeochemical Cycles: Global Change and Human ImpactsAUSTRAL ECOLOGY, Issue 3 2005JOSHUA MACKIE No abstract is available for this article. [source] Global Changes Related to Travelers' HealthJOURNAL OF TRAVEL MEDICINE, Issue 4 2007Brian Gushulak MD First page of article [source] Assessing ecosystem threats from global and regional change: hierarchical modeling of risk to sagebrush ecosystems from climate change, land use and invasive species in Nevada, USAECOGRAPHY, Issue 1 2010Bethany A. Bradley Global change poses significant challenges for ecosystem conservation. At regional scales, climate change may lead to extensive shifts in species distributions and widespread extirpations or extinctions. At landscape scales, land use and invasive species disrupt ecosystem function and reduce species richness. However, a lack of spatially explicit models of risk to ecosystems makes it difficult for science to inform conservation planning and land management. Here, I model risk to sagebrush (Artemisia spp.) ecosystems in the state of Nevada, USA from climate change, land use/land cover change, and species invasion. Risk from climate change is based on an ensemble of 10 atmosphere-ocean general circulation model (AOGCM) projections applied to two bioclimatic envelope models (Mahalanobis distance and Maxent). Risk from land use is based on the distribution of roads, agriculture, and powerlines, and on the spatial relationships between land use and probability of cheatgrass Bromus tectorum invasion in Nevada. Risk from land cover change is based on probability and extent of pinyon-juniper (Pinus monophylla; Juniperus spp.) woodland expansion. Climate change is most likely to negatively impact sagebrush ecosystems at the edges of its current range, particularly in southern Nevada, southern Utah, and eastern Washington. Risk from land use and woodland expansion is pervasive throughout Nevada, while cheatgrass invasion is most problematic in the northern part of the state. Cumulatively, these changes pose major challenges for conservation of sagebrush and sagebrush obligate species. This type of comprehensive assessment of ecosystem risk provides managers with spatially explicit tools important for conservation planning. [source] Global change and carnivore body size: data are stasisGLOBAL ECOLOGY, Issue 2 2009Shai Meiri ABSTRACT Aim, Global warming and other anthropogenic changes to the environment affect many aspects of biology and have often been invoked as causing body size changes in vertebrates. Here we examine a diverse set of carnivore populations in search of patterns in body size change that could reflect global warming (in accord with Bergmann's rule). Location, Global. Methods, We used > 4400 specimens representing 22 carnivore species in 52 populations collected over the last few decades to examine whether size changed with collection date when geography and sex are accounted for. We then examined several factors related to global warming, body mass, diet, and the attributes of the different datasets, to see whether they affect the standardized slope (,) of the size versus time regression. Results, Six of 52 populations we examined show a significant effect of year of collection on body size at the 0.05 probability level. The response of size to global warming does not reflect spatial patterns of size variation, nor do diet or body mass affect tendency of populations to change in body size. Size changes are no more pronounced in populations that have been sampled more recently. However, change, where it occurs, is rapid. Main conclusions, There may be a tendency in the literature to report only cases where recent changes are prevalent. Although in our data only a minority of populations show body size changes, we may see changes accelerating in the future in response to more drastic climatic changes and other anthropogenic changes. [source] Linkages of plant traits to soil properties and the functioning of temperate grasslandJOURNAL OF ECOLOGY, Issue 5 2010Kate H. Orwin Summary 1.,Global change is likely to alter plant community structure, with consequences for the structure and functioning of the below-ground community and potential feedbacks to climate change. Understanding the mechanisms behind these plant,soil interactions and feedbacks to the Earth-system is therefore crucial. One approach to understanding such mechanisms is to use plant traits as predictors of functioning. 2.,We used a field-based monoculture experiment involving nine grassland species that had been growing on the same base soil for 7 years to test whether leaf, litter and root traits associated with different plant growth strategies can be linked to an extensive range of soil properties relevant to carbon, nitrogen and phosphorus cycling. Soil properties included the biomass and structure of the soil microbial community, soil nutrients, soil microclimate and soil process rates. 3.,Plant species with a high relative growth rate (RGR) were associated with high leaf and litter quality (e.g. low toughness, high nitrogen concentrations), an elevated biomass of bacteria relative to fungi in soil, high rates of soil nitrogen mineralization and concentrations of extractable inorganic nitrogen, and to some extent higher available phosphorus pools. 4.,In contrast to current theory, species with a high RGR and litter quality were associated with soils with a lower rate of soil respiration and slow decomposition rates. This indicates that predicting processes that influence carbon cycling from plant traits may be more complex than predicting processes that influence nitrogen and phosphorus cycling. 5.,Root traits did not show strong relationships to RGR, leaf or litter traits, but were strongly correlated with several soil properties, particularly the biomass of bacteria relative to fungi in soil and measures relating to soil carbon cycling. 6.,Synthesis. Our results indicate that plant species from a single habitat can result in significant divergence in soil properties and functioning when grown in monoculture, and that many of these changes are strongly and predictably linked to variation in plant traits associated with different growth strategies. Traits therefore have the potential to be a powerful tool for understanding the mechanisms behind plant,soil interactions and ecosystem functioning, and for predicting how changes in plant species composition associated with global change will feedback to the Earth-system. [source] Herbivore control of annual grassland composition in current and future environmentsECOLOGY LETTERS, Issue 1 2006Halton A. Peters Abstract Selective consumption by herbivores influences the composition and structure of a range of plant communities. Anthropogenically driven global environmental changes, including increased atmospheric carbon dioxide (CO2), warming, increased precipitation, and increased N deposition, directly alter plant physiological properties, which may in turn modify herbivore consumption patterns. In this study, we tested the hypothesis that responses of annual grassland composition to global changes can be predicted exclusively from environmentally induced changes in the consumption patterns of a group of widespread herbivores, the terrestrial gastropods. This was done by: (1) assessing gastropod impacts on grassland composition under ambient conditions; (2) quantifying environmentally induced changes in gastropod feeding behaviour; (3) predicting how grassland composition would respond to global-change manipulations if influenced only by herbivore consumption preferences; and (4) comparing these predictions to observed responses of grassland community composition to simulated global changes. Gastropod herbivores consume nearly half of aboveground production in this system. Global changes induced species-specific changes in plant leaf characteristics, leading gastropods to alter the relative amounts of different plant types consumed. These changes in gastropod feeding preferences consistently explained global-change-induced responses of functional group abundance in an intact annual grassland exposed to simulated future environments. For four of the five global change scenarios, gastropod impacts explained > 50% of the quantitative changes, indicating that herbivore preferences can be a major driver of plant community responses to global changes. [source] Control of chondrocyte gene expression by actin dynamics: a novel role of cholesterol/Ror-, signalling in endochondral bone growthJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 9b 2009Anita Woods Abstract Elucidating the signalling pathways that regulate chondrocyte differentiation, such as the actin cytoskeleton and Rho GTPases, during development is essential for understanding of pathological conditions of cartilage, such as chondrodysplasias and osteoarthritis. Manipulation of actin dynamics in tibia organ cultures isolated from E15.5 mice results in pronounced enhancement of endochondral bone growth and specific changes in growth plate architecture. Global changes in gene expression were examined of primary chondrocytes isolated from embryonic tibia, treated with the compounds cytochalasin D, jasplakinolide (actin modifiers) and the ROCK inhibitor Y27632. Cytochalasin D elicited the most pronounced response and induced many features of hypertrophic chondrocyte differentiation. Bioinformatics analyses of microarray data and expression validation by real-time PCR and immunohistochemistry resulted in the identification of the nuclear receptor retinoid related orphan receptor-, (Ror-,) as a novel putative regulator of chondrocyte hypertrophy. Expression of Ror-, target genes, (Lpl, fatty acid binding protein 4 [Fabp4], Cd36 and kruppel-like factor 5 [Klf15]) were induced during chondrocyte hypertrophy and by cytochalasin D and are cholesterol dependent. Stimulation of Ror-, by cholesterol results in increased bone growth and enlarged, rounded cells, a phenotype similar to chondrocyte hypertrophy and to the changes induced by cytochalasin D, while inhibition of cholesterol synthesis by lovastatin inhibits cytochalasin D induced bone growth. Additionally, we show that in a mouse model of cartilage specific (Col2-Cre) Rac1, inactivation results in increased Hif-1, (a regulator of Rora gene expression) and Ror-,+ cells within hypertrophic growth plates. We provide evidence that cholesterol signalling through increased Ror-, expression stimulates chondrocyte hypertrophy and partially mediates responses of cartilage to actin dynamics. [source] The influence of exercise on foot perfusion in diabetesDIABETIC MEDICINE, Issue 10 2007D. T. Williams Abstract Aims, Diabetic foot disease is associated with both macro- and microvascular disease. Exercise has both positive and negative effects on the perfusion of lower limbs with peripheral arterial occlusive disease (PAOD). We aimed to measure changes in foot perfusion following a brief period of lower-limb exercise in individuals with and without Type 2 diabetes and non-critical PAOD. Methods, Subjects were allocated to groups according to the presence or absence of diabetes, PAOD on colour duplex imaging and clinically detectable peripheral neuropaÍthy. Transcutaneous oxygen tension (TcPO2), transcutaneous carbon dioxide tension (TcPCO2), ankle-brachial pressure indices, toe pressures and toe-brachial pressure indices (TBI) were measured. Results, One hundred and sixteen limbs were studied in 61 subjects. Post-exercise, toe pressure and TBI increased in the non-diabetic group with arterial disease, but not in the groups with diabetes. Foot TcPO2 values increased in groups with diabetes and TcPCO2 decreased in all groups with arterial disease. Increased chest TcPO2 and decreased TcPCO2 were demonstrated in the groups with diabetes. Conclusions, Elevations in foot TcPO2 and reductions in TcPCO2 indicate improved cutaneous perfusion response to local heating post-exercise. Elevated toe pressures in the non-diabetes group suggest that improved perfusion may be associated with enhanced lower limb macrovascular haemodynamics. However, improvements in TcPO2 and TcPCO2 at foot and chest sites in diabetes imply a global change in cutaneous perfusion. The results suggest that brief exercise results in an improvement in cutaneous perfusion in non-critical PAOD, particularly in individuals with diabetes. [source] Climatic adaptation in an isolated and genetically impoverished amphibian populationECOGRAPHY, Issue 4 2010Germán Orizaola The capacity of populations to respond adaptively to environmental change is essential for their persistence. Isolated populations often harbour reduced genetic variation, which is predicted to decrease adaptive potential, and can be detrimental under the current scenarios of global change. In this study, we examined climatic adaptation in larval life history traits in the pool frog Rana lessonae along a latitudinal gradient across the northern distribution area of the species, paying special attention to the isolated and genetically impoverished fringe populations in central Sweden. Larvae from eight populations within three geographic areas (Poland, Latvia and Sweden) were reared under three temperatures (19, 22 and 26°C) in a common garden laboratory experiment. We found clear evidence for latitudinal adaptation in R. lessonae populations, larvae from higher latitudes growing and developing faster than low-latitude ones. Larvae from the Swedish populations were able to compensate for the effects of cooler temperatures and a shorter growth season with genetically higher growth and development rates (i.e. countergradient variation) in the two higher temperature treatments, but there was no difference among the populations at the lowest temperature treatment, which is likely to be close to the temperature limiting growth in R. lessonae. Our results demonstrate that isolated and genetically impoverished populations can be locally adapted, and identify the Swedish fringe populations as a significant conservation unit adapted to the northern environmental conditions. [source] Contrasting spatial and temporal global change impacts on butterfly species richness during the 20th centuryECOGRAPHY, Issue 6 2006Peter White Regional patterns of species richness are often explained by models using temperature or measures habitat suitability. Generally, species richness is positively associated with temperature, and negatively associated with habitat degradation. While these models have been well tested across spatial scales, they have rarely been tested on a temporal scale , in part due to the difficulty in ascertaining accurate historical data at an appropriate resolution. In this study, we compared the results of temporal and spatial models, each incorporating two predictors of species richness: temperature, and human population density (as a surrogate of human-related habitat impacts). We found that the change in species richness from the early to late part of the 20th century was positively correlated with temperature change, and negatively correlated with human population density change. When we compared these results to two spatial models using contemporary and historic data, the spatial effects of temperature on butterfly richness were similar to its temporal effects, while the effect of human population density through time is the opposite of its spatial effect. More generally, the assumption that spatial patterns are equivalent to temporal ones when applying macroecological data to global change is clearly unreliable. [source] Appraising the roles of nutrient availability, global change, and functional traits during the angiosperm rise to dominanceECOLOGY LETTERS, Issue 5 2010Kevin E. Mueller Ecology Letters (2010) 13: E1,E6 Abstract To explain the rise of angiosperms during the Cretaceous, Berendse & Scheffer (Ecol. Lett., 12, 2009, 865) invoke feedbacks between leaf litter, soil nutrients, and growth, overlooking other factors affecting resource acquisition by Cretaceous plants. We evaluate their hypothesis, highlight alternative explanations, and emphasize use of a broader framework for understanding the angiosperm radiation. [source] The rise of research on futures in ecology: rebalancing scenarios and predictionsECOLOGY LETTERS, Issue 12 2009Audrey Coreau Abstract Concern about the ecological consequences of global change has increasingly stimulated ecologists to examine the futures of ecological systems. Studying futures is not only a crucial element of the interaction between science, management and decision making, but also a critical research challenge per se, especially because futures cannot be observed or experimented on. In addition, researchers can encounter methodological and theoretical difficulties, which make interpretations and predictions problematic. In the literature which deals with futures of ecological systems two main lines of research can be distinguished: a predictive approach, which dominates the literature, can be contrasted with a rarer number of studies that elaborate potential scenarios for ecological systems. Scenario approaches currently concern mainly contacts with stakeholders or decision makers, or the use of climate scenarios to derive projections about ecological futures. We argue that a new direction for ecological futures research could be explored by using ecological scenarios in combination with predictive models to further fundamental ecological research, in addition to enhancing its applied value. Ecology Letters (2009) 12: 1277,1286 [source] The merging of community ecology and phylogenetic biologyECOLOGY LETTERS, Issue 7 2009Jeannine Cavender-Bares Abstract The increasing availability of phylogenetic data, computing power and informatics tools has facilitated a rapid expansion of studies that apply phylogenetic data and methods to community ecology. Several key areas are reviewed in which phylogenetic information helps to resolve long-standing controversies in community ecology, challenges previous assumptions, and opens new areas of investigation. In particular, studies in phylogenetic community ecology have helped to reveal the multitude of processes driving community assembly and have demonstrated the importance of evolution in the assembly process. Phylogenetic approaches have also increased understanding of the consequences of community interactions for speciation, adaptation and extinction. Finally, phylogenetic community structure and composition holds promise for predicting ecosystem processes and impacts of global change. Major challenges to advancing these areas remain. In particular, determining the extent to which ecologically relevant traits are phylogenetically conserved or convergent, and over what temporal scale, is critical to understanding the causes of community phylogenetic structure and its evolutionary and ecosystem consequences. Harnessing phylogenetic information to understand and forecast changes in diversity and dynamics of communities is a critical step in managing and restoring the Earth's biota in a time of rapid global change. [source] Temporal dynamics within a contemporary latitudinal diversity gradientECOLOGY LETTERS, Issue 9 2008Jonathan A. D. Fisher Abstract Poleward declines in species diversity [latitudinal diversity gradients (LDG)] remain among the oldest and most widespread of macroecological patterns. However, their contemporary dynamics remain largely unexplored even though changing ecological conditions, including global change, may modify LDG and their respective ecosystems. Here, we examine temporal variation within a temperate Northwest Atlantic LDG using 31 years of annual fisheries-independent surveys and explore its dynamics in relation to a dominant climate signal [the wintertime North Atlantic Oscillation (NAO)] that varies interannually and alters the latitudinal gradient of Northwest Atlantic continental shelf bottom water temperatures. We found that the slopes of the annual LDG vary dramatically due to changes in geographic distributions of 100+ species, variations that are concealed within the cumulative, static LDG. These changes are strongly associated with changes in NAO sign and strength. This is the first illustration of temporal dynamics in a contemporary LDG and the first demonstration of the speed at which local environmental variations can alter an LDG. Our findings underscore the need to investigate factors that modify LDG separately from those that contribute to their origins. [source] Community responses to contaminants: Using basic ecological principles to predict ecotoxicological effectsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2009William H. Clements Abstract Community ecotoxicology is defined as the study of the effects of contaminants on patterns of species abundance, diversity, community composition, and species interactions. Recent discoveries that species diversity is positively associated with ecosystem stability, recovery, and services have made a community-level perspective on ecotoxicology more important than ever. Community ecotoxicology must explicitly consider both present and impending global change and shift from a purely descriptive to a more predictive science. Greater consideration of the ecological factors and threshold responses that determine community resistance and resilience should improve our ability to predict how and when communities will respond to, and recover from, xenobiotics. A better understanding of pollution-induced community tolerance, and of the costs of this tolerance, should facilitate identifying contaminant-impacted communities, thus forecasting the ecological consequences of contaminant exposure and determining the restoration effectiveness. Given the vast complexity of community ecotoxicology, simplifying assumptions, such as the possibility that the approximately 100,000 registered chemicals could be reduced to a more manageable number of contaminant classes with similar modes of action, must be identified and validated. In addition to providing a framework for predicting contaminant fate and effects, food-web ecology can help to identify communities that are sensitive to contaminants, contaminants that are particularly insidious to communities, and species that are crucial for transmitting adverse effects across trophic levels. Integration of basic ecological principles into the design and implementation of ecotoxicological research is essential for predicting contaminant effects within the context of rapidly changing, global environmental conditions. [source] Adaptation, extinction and global changeEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 1 2008Graham Bell Abstract We discuss three interlinked issues: the natural pace of environmental change and adaptation, the likelihood that a population will adapt to a potentially lethal change, and adaptation to elevated CO2, the prime mover of global change. 1.,Environmental variability is governed by power laws showing that ln difference in conditions increases with ln elapsed time at a rate of 0.3,0.4. This leads to strong but fluctuating selection in many natural populations. 2.,The effect of repeated adverse change on mean fitness depends on its frequency rather than its severity. If the depression of mean fitness leads to population decline, however, severe stress may cause extinction. Evolutionary rescue from extinction requires abundant genetic variation or a high mutation supply rate, and thus a large population size. Although natural populations can sustain quite intense selection, they often fail to adapt to anthropogenic stresses such as pollution and acidification and instead become extinct. 3.,Experimental selection lines of algae show no specific adaptation to elevated CO2, but instead lose their carbon-concentrating mechanism through mutational degradation. This is likely to reduce the effectiveness of the oceanic carbon pump. Elevated CO2 is also likely to lead to changes in phytoplankton community composition, although it is not yet clear what these will be. We emphasize the importance of experimental evolution in understanding and predicting the biological response to global change. This will be one of the main tasks of evolutionary biologists in the coming decade. [source] Potential changes in skipjack tuna (Katsuwonus pelamis) habitat from a global warming scenario: modelling approach and preliminary resultsFISHERIES OCEANOGRAPHY, Issue 4-5 2003Harilaos Loukos Abstract Recent studies suggest a reduction of primary production in the tropical oceans because of changes in oceanic circulation under global warming conditions caused by increasing atmospheric CO2 concentration. This might affect the productivity of medium and higher trophic levels with potential consequences on marine resources such as tropical tuna. Here we combine the projections of up-to-date climate and ocean biogeochemical models with recent concepts of representation of fish habitat based on prey abundance and ambient temperature to gain some insight into the impact of climate change on skipjack tuna (Katsuwonus pelamis), the species that dominates present-day tuna catch. For a world with doubled atmospheric CO2 concentration, our results suggest significant large-scale changes of skipjack habitat in the equatorial Pacific. East of the date line, conditions could be improved by an extension of the present favourable habitat zones of the western equatorial Pacific, a feature reminiscent of warming conditions associated with El Niño events. Despite its simplicity and the associated underlying hypothesis, this first simulation is used to stress future research directions and key issues for modelling developments associated to global change. [source] Lake responses to reduced nutrient loading , an analysis of contemporary long-term data from 35 case studiesFRESHWATER BIOLOGY, Issue 10 2005ERIK JEPPESEN Summary 1. This synthesis examines 35 long-term (5,35 years, mean: 16 years) lake re-oligotrophication studies. It covers lakes ranging from shallow (mean depth <5 m and/or polymictic) to deep (mean depth up to 177 m), oligotrophic to hypertrophic (summer mean total phosphorus concentration from 7.5 to 3500 ,g L,1 before loading reduction), subtropical to temperate (latitude: 28,65°), and lowland to upland (altitude: 0,481 m). Shallow north-temperate lakes were most abundant. 2. Reduction of external total phosphorus (TP) loading resulted in lower in-lake TP concentration, lower chlorophyll a (chl a) concentration and higher Secchi depth in most lakes. Internal loading delayed the recovery, but in most lakes a new equilibrium for TP was reached after 10,15 years, which was only marginally influenced by the hydraulic retention time of the lakes. With decreasing TP concentration, the concentration of soluble reactive phosphorus (SRP) also declined substantially. 3. Decreases (if any) in total nitrogen (TN) loading were lower than for TP in most lakes. As a result, the TN : TP ratio in lake water increased in 80% of the lakes. In lakes where the TN loading was reduced, the annual mean in-lake TN concentration responded rapidly. Concentrations largely followed predictions derived from an empirical model developed earlier for Danish lakes, which includes external TN loading, hydraulic retention time and mean depth as explanatory variables. 4. Phytoplankton clearly responded to reduced nutrient loading, mainly reflecting declining TP concentrations. Declines in phytoplankton biomass were accompanied by shifts in community structure. In deep lakes, chrysophytes and dinophytes assumed greater importance at the expense of cyanobacteria. Diatoms, cryptophytes and chrysophytes became more dominant in shallow lakes, while no significant change was seen for cyanobacteria. 5. The observed declines in phytoplankton biomass and chl a may have been further augmented by enhanced zooplankton grazing, as indicated by increases in the zooplankton : phytoplankton biomass ratio and declines in the chl a : TP ratio at a summer mean TP concentration of <100,150 ,g L,1. This effect was strongest in shallow lakes. This implies potentially higher rates of zooplankton grazing and may be ascribed to the observed large changes in fish community structure and biomass with decreasing TP contribution. In 82% of the lakes for which data on fish are available, fish biomass declined with TP. The percentage of piscivores increased in 80% of those lakes and often a shift occurred towards dominance by fish species characteristic of less eutrophic waters. 6. Data on macrophytes were available only for a small subsample of lakes. In several of those lakes, abundance, coverage, plant volume inhabited or depth distribution of submerged macrophytes increased during oligotrophication, but in others no changes were observed despite greater water clarity. 7. Recovery of lakes after nutrient loading reduction may be confounded by concomitant environmental changes such as global warming. However, effects of global change are likely to run counter to reductions in nutrient loading rather than reinforcing re-oligotrophication. [source] PERSPECTIVE: Rethinking the value of high wood densityFUNCTIONAL ECOLOGY, Issue 4 2010Markku Larjavaara Summary 1.,Current thinking holds that wood density mediates a tradeoff between strength and economy of construction, with higher wood density providing higher strength but at higher cost. 2.,Yet the further away wood fibres are from the central axis of the trunk, the more they increase the strength of the trunk; thus, a fat trunk of low-density wood can achieve greater strength at lower construction cost than a thin trunk of high-density wood. 3.,What then are the countervailing advantages of high wood density? 4.,We hypothesize that high wood density is associated with lower maintenance costs due to lower trunk surface area, as surface area correlates with maintenance respiration. 5.,This advantage would be particularly important to long-lived trees and could in part explain why they tend to have high wood density. 6.,High wood density has also been associated with lower risk of trunk breakage, xylem implosion and pathogen invasion, but we argue that these relationships are not causal and instead reflect correlated selection on other traits of value to long-lived trees. 7.,This revaluation of the costs and benefits of high wood density has important implications for understanding tree life-history evolution, functional diversity, forest carbon stocks and the impacts of global change. [source] Plant functional group identity influences short-term peatland ecosystem carbon flux: evidence from a plant removal experimentFUNCTIONAL ECOLOGY, Issue 2 2009Susan E. Ward Summary 1Northern hemisphere peatlands are globally important stores of organic soil carbon. We examined effects of plant functional group identity on short-term carbon (C) flux in an ombrotrophic peatland in northern England, UK, by selectively removing one of each of the three dominant plant functional groups (ericoid dwarf-shrubs, graminoids and bryophytes). Carbon dynamics were quantified by a combination of CO2 flux measurements and 13CO2 stable isotope pulse labelling approaches. 2Significant effects of plant functional group removals on CO2 fluxes and tracer 13C uptake and turnover were detected. Removal of ericoid dwarf-shrubs had the greatest influence on gross CO2 flux, increasing rates of respiration and photosynthesis by > 200% relative to the undisturbed control. After pulse labelling with 13CO2, we found that turnover of recent photosynthate, measured as respired 13CO2, was also greatest in the absence of dwarf-shrubs. 3Analysis of 13C tracer enrichment in leaf tissues from all plant removal treatments showed that the rate of fixation of 13CO2 and turnover of 13C labelled photosynthate in leaf tissue was greatest in graminoids and lowest in bryophytes. Furthermore, graminoid leaf 13C enrichment was greatest when growing in the absence of dwarf-shrubs, suggesting that the presence of dwarf-shrubs reduced the photosynthetic activity of graminoids. 4We conclude that plant functional groups differentially influence the uptake and short-term flux of carbon in peatlands, suggesting that changes in the functional composition of vegetation resulting from global change have the potential to alter short-term patterns of carbon exchange in peatland. [source] Evolution on ecological time-scalesFUNCTIONAL ECOLOGY, Issue 3 2007S. P. CARROLL Summary 1Ecologically significant evolutionary change, occurring over tens of generations or fewer, is now widely documented in nature. These findings counter the long-standing assumption that ecological and evolutionary processes occur on different time-scales, and thus that the study of ecological processes can safely assume evolutionary stasis. Recognition that substantial evolution occurs on ecological time-scales dissolves this dichotomy and provides new opportunities for integrative approaches to pressing questions in many fields of biology. 2The goals of this special feature are twofold: to consider the factors that influence evolution on ecological time-scales , phenotypic plasticity, maternal effects, sexual selection, and gene flow , and to assess the consequences of such evolution , for population persistence, speciation, community dynamics, and ecosystem function. 3The role of evolution in ecological processes is expected to be largest for traits that change most quickly and for traits that most strongly influence ecological interactions. Understanding this fine-scale interplay of ecological and evolutionary factors will require a new class of eco-evolutionary dynamic modelling. 4Contemporary evolution occurs in a wide diversity of ecological contexts, but appears to be especially common in response to anthropogenic changes in selection and population structure. Evolutionary biology may thus offer substantial insight to many conservation issues arising from global change. 5Recent studies suggest that fluctuating selection and associated periods of contemporary evolution are the norm rather than exception throughout the history of life on earth. The consequences of contemporary evolution for population dynamics and ecological interactions are likely ubiquitous in time and space. [source] Several components of global change alter nitrifying and denitrifying activities in an annual grasslandFUNCTIONAL ECOLOGY, Issue 4 2006R. BARNARD Summary 1The effects of global change on below-ground processes of the nitrogen (N) cycle have repercussions for plant communities, productivity and trace gas effluxes. However, the interacting effects of different components of global change on nitrification or denitrification have rarely been studied in situ. 2We measured responses of nitrifying enzyme activity (NEA) and denitrifying enzyme activity (DEA) to over 4 years of exposure to several components of global change and their interaction (increased atmospheric CO2 concentration, temperature, precipitation and N addition) at peak biomass period in an annual grassland ecosystem. In order to provide insight into the mechanisms controlling the response of NEA and DEA to global change, we examined the relationships between these activities and soil moisture, microbial biomass C and N, and soil extractable N. 3Across all treatment combinations, NEA was decreased by elevated CO2 and increased by N addition. While elevated CO2 had no effect on NEA when not combined with other treatments, it suppressed the positive effect of N addition on NEA in all the treatments that included N addition. We found a significant CO2,N interaction for DEA, with a positive effect of elevated CO2 on DEA only in the treatments that included N addition, suggesting that N limitation of denitrifiers may have occurred in our system. Soil water content, extractable N concentrations and their interaction explained 74% of the variation in DEA. 4Our results show that the potentially large and interacting effects of different components of global change should be considered in predicting below-ground N responses of Mediterranean grasslands to future climate changes. [source] | ||||||||||||||||||||||||||||||||||||||||||||||