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911.
Robert S. Rempel 《Ecological modelling》2011,222(18):3355-3365
Interest in the response of moose to climate change has increased because of the potential role they play in the conservation of woodland caribou, and threatened loss to recreational and economic opportunities. The objective of this study is to develop a plausible, parsimonious, systems-level model of moose population dynamics that will be useful in exploring the response of moose populations to climate projections. The study begins with a statistical model of moose carrying capacity, which is then integrated into a systems-level model that predicts moose density based on explicit causal factors. Scenario analysis was conducted using a variety of assumptions concerning biotic and abiotic interactions, and under the A2 climate scenario all model scenarios predict a decline of moose density at the southern limits of the Ontario distribution and an increase at the northern extents. Predicted declines are a result of lower carrying capacity and higher heat stress, parasite loads and wolf predation. Given the sensitivity of the model to density-dependent factors, the indirect effect of parasites on decreased recruitment may have greater impact on moose than the direct effect of increased death rate. Results indicate that conservation planning for woodland caribou populations should account for possible increases in moose and wolf populations. 相似文献
912.
DAVID P. EDWARDS PAUL WOODCOCK ROB J. NEWTON FELICITY A. EDWARDS DAVID J. R. ANDREWS TEEGAN D. S. DOCHERTY SIMON L. MITCHELL TAKAHIRO OTA SUZAN BENEDICK SIMON H. BOTTRELL KEITH C. HAMER 《Conservation biology》2013,27(5):1079-1086
Effects of logging on species composition in tropical rainforests are well known but may fail to reveal key changes in species interactions. We used nitrogen stable‐isotope analysis of 73 species of understory birds to quantify trophic responses to repeated intensive logging of rainforest in northern Borneo and to test 4 hypotheses: logging has significant effects on trophic positions and trophic‐niche widths of species, and the persistence of species in degraded forest is related to their trophic positions and trophic‐niche widths in primary forest. Species fed from higher up the food chain and had narrower trophic‐niche widths in degraded forest. Species with narrow trophic‐niche widths in primary forest were less likely to persist after logging, a result that indicates a higher vulnerability of dietary specialists to local extinction following habitat disturbance. Persistence of species in degraded forest was not related to a species’ trophic position. These results indicate changes in trophic organization that were not apparent from changes in species composition and highlight the importance of focusing on trophic flexibility over the prevailing emphasis on membership of static feeding guilds. Our results thus support the notion that alterations to trophic organization and interactions within tropical forests may be a pervasive and functionally important hidden effect of forest degradation. Flexibilidad Trófica y la Persistencia de Aves de Sotobosque en un Bosque Lluvioso Talado Intensivamente 相似文献
913.
Climate change, humidity, and mortality in the United States 总被引:2,自引:0,他引:2
Alan I. Barreca 《Journal of Environmental Economics and Management》2012,63(1):19-34
This paper estimates the effects of humidity and temperature on mortality rates in the United States (c. 1973-2002) in order to provide an insight into the potential health impacts of climate change. I find that humidity, like temperature, is an important determinant of mortality. Coupled with Hadley CM3 climate-change predictions, I project that mortality rates are likely to change little on the aggregate for the United States. However, distributional impacts matter: mortality rates are likely to decline in cold and dry areas, but increase in hot and humid areas. Further, accounting for humidity has important implications for evaluating these distributional effects. 相似文献
914.
915.
Attribution studies investigate the causes of recent global warming. For a few decades the scientific community generally adopted dynamical models – the so-called Global Climate Models (GCMs) – for such an investigation. These models show the essential role of anthropogenic forcings in driving the temperature behaviour of the last half century. In the last period even other (data-driven) methodological approaches were adopted for attribution studies. This allows the scientific community to compare the results coming from these different approaches and to possibly increase their robustness. For such a purpose, the paper explores the possibility of applying a robustness framework, so far used only in the case of multi-model GCM ensembles, to a strategy including models from different methodological orientations, assessing such an application especially in the light of the independence issue. 相似文献
916.
This study examined two methods for jointly considering the environmental impact and nutritional quality of diets, which is necessary when designing policy instruments promoting sustainable food systems. Both methods included energy content and 18 macro- and micronutrients in the diet, the climate impact, land use and biodiversity damage potential. In Method 1, the content of different nutrients in the diet was normalised based on recommended intake or upper levels for average daily intake and presented together with the environmental impacts, which were normalised according to estimated sustainable levels. In Method 2, the nutritional quality of different diets was considered by calculating their nutrient density score, and the environmental impact was then expressed per nutrient density score. Three diets were assessed; a diet corresponding to Nordic recommendations, the current average Swedish diet and a lifestyle Low Carbohydrate-High Fat (LCHF) diet. Method 1 clearly showed that the climate impact was far beyond the sustainable level for all diets, while land use was within the sustainability limit for the recommended diet, but not the other two. Comparisons based on nutrient density scores depended on the score used, but the current and LCHF diets had more impact than the recommended diet (less livestock products) for all but one score. Over- and under-consumption of nutrients were clearly shown by Method 1 but not possible to distinguish with Method 2, as normalisation was not possible, making it difficult to evaluate the absolute scale of the impacts when nutrient density scores were used. For quantitative information on the environmental and nutritional impacts of diets as support in decision-making processes, it is important that data presentation is transparent. There is limited value in reducing results to a low number of indicators that are easy to read, but difficult to interpret, e.g. nutrient density score. Method 1 allows combined assessment of diets regarding environmental impact and nutritional intake and could be useful in dietary planning and in development of dietary recommendations and other policy instruments to achieve more sustainable food systems. 相似文献
917.
P. Smith J. U. Smith U. Franko K. Kuka V. A. Romanenkov L. K. Shevtsova M. Wattenbach P. Gottschalk O. D. Sirotenko D. I. Rukhovich P. V. Koroleva I. A. Romanenko N. V. Lisovoi 《Regional Environmental Change》2007,7(2):105-119
Three soil carbon models (RothC, CANDY and the Model of Humus Balance) were used to estimate the impacts of climate change
on agricultural mineral soil carbon stocks in European Russia and the Ukraine using detailed spatial data on land-use, future
land-use, cropping patterns, agricultural management, climate and soil type. Scenarios of climate were derived from the Hadley
Centre climate Version 3 (HadCM3) model; future yields were determined using the Soil–Climate–Yield model, and land use was
determined from regional agricultural and economic data and a model of agricultural economics. The models suggest that optimal
management, which entails the replacement of row crops with other crops, and the use of extra years of grass in the rotation
could reduce Soil organic carbon (SOC) loss in the croplands of European Russia and the Ukraine by 30–44% compared to the
business-as-usual management. The environmentally sustainable management scenario (SUS), though applied for a limited area
within the total region, suggests that much of this optimisation could be realised without damaging profitability for farmers. 相似文献
918.
Jacek Andrzej Urbanski 《Journal of Coastal Conservation》2001,7(2):155-162
A DTM (Digital Terrain Model) map and the analytical powers of GIS (Geographical Information System) were used in deterministic
and probabilistic methods for analysis of inundation of a coastal area. These methods were applied to evaluate the effects
of a rise in sea-level on the coastal zone of the Puck Lagoon (Poland) over a period of 100 years. The analysis evaluated
the following aspects: the threat to man-made objects such as buildings and roads; changes in the impact of the sea on the
coastal environment manifested as the frequency of flooding of grasslands and marshland in the coastal depression, and the
formation of a dune embankment. The analysis covered a ca. 5 km stretch of low-lying coastline, in which there are two rapidly
growing villages and a nature reserve. The study showed that a sealevel rise of 40 cm would increase the frequency of flooding
in the area and would probably cause the dune ridge vegetation to deteriorate. 相似文献
919.
Climate change, land degradation and drought affect millions of people living in drylands worldwide. With its food security depending almost entirely on irrigated agriculture, Central Asia is one of the arid regions highly vulnerable to water scarcity. Previous research of land and water use in the region has focused on improving water-use efficiency, soil management and identifying technical, institutional and agricultural innovations. However, vulnerability to climate change has rarely been considered, in spite of the imminent risks due to a higher-than-average warming perspective and the predicted melting of glaciers, which will greatly affect the availability of irrigation water. Using the Khorezm region in the irrigated lowlands of northwest Uzbekistan as an example, we identify the local patterns of vulnerability to climate variability and extremes. We look at on-going environmental degradation, water-use inefficiency, and barriers to climate change adaptation and mitigation, and based on an extensive review of research evidence from the region, we present concrete examples of initiatives for building resilience and improving climate risk management. These include improving water use efficiency and changing the cropping patterns that have a high potential to decrease the exposure and sensitivity of rural communities to climate risks. In addition, changes in land use such as the afforestation of degraded croplands, and introducing resource-smart cultivation practices such as conservation agriculture, may strengthen the capacity of farmers and institutions to respond to climate challenges. As these can be out-scaled to similar environments, i.e. the irrigated cotton and wheat growing lowland regions in Central Asia and the Caucasus, these findings may be relevant for regions beyond the immediate geographic area from which it draws its examples. 相似文献
920.
《Environmental Communication: A Journal of Nature and Culture》2013,7(3):355-366
This paper investigates how the mass media may influence information-seeking behavior through an analysis of how the release of the movie The Day After Tomorrow, a fictional depiction of global warming causing catastrophic natural disasters, changed the information-seeking behavior of the public on global warming related websites. A “teachable moment” of elevated information-seeking activity was found to extend from 10 days before the release date of The Day After Tomorrow to 19 days after the movie release date. Using Auto Regressive Integrated Moving Average modeling, a significant positive correlation was found between changes in media coverage of The Day After Tomorrow and changes in information-seeking activity, although the correlation did not support hypothesized time lags. These results are discussed in terms of information-seeking models, and new research directions are proposed to link agenda-setting research with the information-seeking literature. 相似文献