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991.
The paper considers the extent to which social–ecological systems research might contribute to an improved understanding of the social and environmental impacts of teleconnections inherent in economic globalisation. Recognising the importance and specificity of regional interconnections, wherein actions in certain parts of the world impact quite specifically on the sustainability of certain other spatially distant places and systems, the paper reflects on the social and environmental implications of increasingly interconnected agri-food systems and intersecting global commodity chains. Key elements of social–ecological systems approaches, which have purported relevance to research on globalisation, are critically examined, and aspects of social–ecological systems thinking that pose challenges for its application in this context are considered. Wider implications and limitations of social–ecological systems approaches to research and practice in (global) governance for sustainability are discussed. The general conclusion is that social–ecological systems research may offer insights into the governance of social and environmental impacts of agri-food systems and other complex systems at certain scales. However, the formal utility of concepts like resilience, vulnerability and adaptability becomes considerably less clear as research turns to analyses of larger, complex, globally teleconnected systems, where the main contribution of such concepts may lie in their metaphorical appeal to important aspects of interconnectivity and interdependence.  相似文献   
992.
The unpredictability of human behavior toward wildlife, coupled with changes in human behavior over space and time, are integral challenges of today's wildlife managers to meet administrative mandates. These challenges are exacerbated by extensive urban development and human population growth along with recent successes in wildlife conservation, leading to increasing encounters, and conflicts, between humans and wildlife. Thus, wildlife management is increasingly concerned with managing the co-existence of people and wildlife in a diminishing wild. However, attempting to analyze human–wildlife encounters, or solve human–wildlife conflicts, continues to be problematic. No structured behavior theory exists on how to address these management challenges. This study is a first attempt to do so through assembling and analyzing existing social-psychological, human-environment, and human–wildlife behavior theories and models in regard to their relevance to human–wildlife encounters. We illustrate the need to move from individualistic social and ecological approaches to an integrated complexity-theory based approach. We argue that human–wildlife encounters can only be understood and modified toward resilient relationships when treated as a complex social-ecological system. Key factors identified across literature impacting formation of positive and negative perceptions and behavior decision-making during an encounter are: cognition and emotions formed through beliefs and experiences across scales, barriers and benefits to specific behavior choices, and social thresholds. Using this multi-disciplinary approach, models and theories are drawn upon to develop the Integrated Adaptive Behavior Model of human–wildlife encounters.  相似文献   
993.
Many developed countries in Annex B of the Kyoto Protocol have been able to report decreasing emissions, and some have officially fulfilled their CO2 reduction commitments. This is in part because current reporting and regulatory regimes allow these countries to displace emissions intensive production offshore. Using a new highly detailed account of emissions embodied in international trade we investigate this phenomenon of emissions leakage. We independently confirm previous findings that adjusting for trade, developed countries emissions have increased, not decreased. We find that the sectors successfully holding or lowering their domestic emissions are often the same as those increasing their imports of embodied CO2. We also find that the fastest growing flow paths of embodied CO2 largely originate outside the Kyoto Annex B signatory nations. Finally, we find that historically the same phenomenon of emissions displacement has already occurred for air pollution, with the result that despite aggressive legislation in major emitters total global air pollution emissions have increased. If regulatory policies do not account for embodied imports, global emissions are likely to rise even if developed countries emitters enforce strong national emissions targets.  相似文献   
994.
The present study focuses on the impact of ocean state (i.e., salinity and temperature) updates on the sea-ice analysis and short-term forecast in an assimilative sea ice–ocean coupled system. A relatively simple sea-ice assimilation scheme was applied to the sea ice–ocean coupled North Atlantic Nucleus for European Modelling of the Ocean (NEMO) system with a focus on the Canadian East Coast. In this assimilation scheme the ocean state was updated directly based on the correlations between the model's sea-ice concentration and the upper ocean salinity and temperature. These correlations were based on a limited time ensemble generated by applying random perturbations to the atmospheric forcing fields. High deviations in the sea-ice conditions were found along the ice edge, implying that the sea-ice edge position is sensitive to small atmospheric forcing variations. Assimilation runs with and without ocean state updates (i.e., sea-ice concentration nudging) were conducted and compared for the winter of 2002. Both continuous and intermittent assimilation schemes were examined. In a continuous sea-ice assimilation experiment, the ocean direct update is unnecessary. When the sea-ice updates are introduced intermittently the ocean state has to be altered to accommodate them, or they will be rapidly diminished by the model's dynamics. The correlations between sea-ice concentration and ocean salinity and temperature based on the first 15 days of January were used for corrections during the entire winter season when, in addition to thermodynamic processes, dynamic processes are responsible for, and even dominate, sea-ice evolution on the Labrador and Newfoundland shelves. This was an adequate choice as was demonstrated by the results of the study which showed that the experiments with ocean state adjustments generated more accurate short-term sea-ice forecasts.  相似文献   
995.
The control mechanisms of topography on alpine treeline pattern are critical to understanding treeline dynamics and future changes. These mechanisms have not been understood quite well enough because of increasing human disturbance and low data resolution. In this study, the relationship between the treeline pattern and topography was analyzed based on high spatial resolution remote sensing data and a digital elevation model in an area in Changbai Mountain with little human disturbance. Future treeline patterns were also predicted. The results showed that(a) aspects with high solar radiation and low snow cover have a high coverage rate of trees,(b) the peak coverage rate of trees switches from low slopes(5°) to medium slopes(5°~25°) as the elevation rises because of the extreme environment,(c) the coverage rate of trees is a function that depends on environmental factors controlled by topography,(d) the future treeline pattern is controlled by new temperature mechanisms, new environmental factors and the reallocation effect of topography. Our research implies that topography controls the treeline pattern and changes in the treeline pattern associated with global warming, due to the effect of global warming on environmental factors. This study may well explain the causes of heterogeneous changes in the treeline pattern in the horizontal direction as well as differences in treeline response to climate warming.  相似文献   
996.
Steller chamaejasme L. (S. chamaejasme for short) is one of the most noxious unpalatable weeds in China, which has been frequently reported its negative interaction (i.e. competition and allelopathy) with other herbaceous species in grasslands. This study compared species diversity, biomass and sexual reproduction of herbaceous plants in meadows with S. chamaejasme and in open meadows without S. chamaejasme in overgrazing meadows on the Tibetan Plateau in China to determine whether positive facilitation exist between S. chamaejasme and other herbaceous species under livestock’s overgrazing. The results showed that there are more herbaceous species in meadows with S. chamaejasme than those in open meadows (35s and 30s, respectively). Diversity index and above-ground biomass were also significantly higher in meadows with S. chamaejasme. There were 39% (11/28) of all species with sexual reproduction found in meadows with S. chamaejasme, which was 7 times more than those in open meadows. Our study showed that S. chamaejasme could provide biotic refuge for neighboring plants and preserve plant diversity from livestock’s overgrazing in alpine meadows on the Tibetan Plateau. It also suggested that inter-specific facilitation between S. chamaejasme and other herbaceous species may play a key role in overgrazing alpine meadows.  相似文献   
997.
998.
Existing research on people–place dynamics often focuses on either physical environment or social dimensions, but many theoretical models posit that both factors are important. I argue that rural communes provide unique settings to explore both social and environmental aspects of place. Based on qualitative interview data with members of two communes, I address emotional connection to the land, changing social relationships over time, and the interplay of physical and social aspects of place. Results demonstrate how the connections to land and social ties are both prevalent. However, social interaction has decreased while commitment to sharing and protecting the physical environment has endured.  相似文献   
999.
1000.
In this study, we developed a prior-knowledge-based spectral mixture analysis (PKSMA) to map impervious surfaces by using endmembers derived separately for high- and low-density urban regions. First, an urban area was categorized into high- and low-density urban areas, using a multi-step classification method. Next, in high-density urban areas that were assumed to have only vegetation and impervious surfaces (ISs), the vegetation–impervious model (V–I) was used in a spectral mixture analysis (SMA) with three endmembers: vegetation, high albedo, and low albedo. In low-density urban areas, the vegetation–impervious–soil model (V–I–S) was used in an SMA analysis with four endmembers: high albedo, low albedo, soil, and vegetation. The fraction of IS with high and low albedo in each pixel was combined to produce the final IS map. The root mean-square error (RMSE) of the IS map produced using PKSMA was about 11.0%, compared to 14.52% only using four-endmember SMA. Particularly in high-density urban areas, PKSMA (RMSE = 6.47%) showed better performance than four-endmember (15.91%). The results indicate that PKSMA can improve IS mapping compared to traditional SMA by using appropriately selected endmembers and is particularly strong in high-density urban areas.  相似文献   
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