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281.
The aim of this paper is to explore the issue of problem definition in coastal (zone) management, with particular emphasis on social and institutional aspects. Do the existing scientific theories provide the necessary tools for open formulation of questions or problem definition, without preconceived ideas? Or are they rigid frameworks, which lead our curiosity along well-paved trails to predetermined results? Formulation of the right questions is probably the most important step in arriving at relevant answers.  相似文献   
282.
In this study, we investigate association patterns of 249 bottlenose dolphin feeding groups off Sardinia Island (Italy) from January 2000–May 2007 and describe how their association behaviour is related to their response to food patches created by a marine fin fish farm. We also tested the hypothesis that dolphins have different social structures with different feeding activities: Associations should decrease during opportunistic feeding behaviours as it is easier to capture prey, and cooperation is not as necessary. Sixteen individually identified bottlenose dolphins were observed participating in both opportunistic and not opportunistic feeding activities, with a mean of 30 ± 8 times and 9.6 ± 1 times, respectively. Bottlenose dolphins show non-random social behaviour during feeding and this behaviour differs depending on their specific foraging activity. Dolphin associations during feeding can be divided into three categories: acquaintances, affiliates, and feeding associates. Association behaviour during fish farm feeding is consistent with our hypothesis that during opportunistic behaviours, benefits from cooperation decrease, as it is easier to capture prey. Group size homogeneity in both feeding activities demonstrates that the number of dolphins engaging in foraging is not necessarily related with cooperation levels. Moreover, an adult dolphin may prefer to associate with a specific individual, independent of the sex, who shares the same foraging priorities. This study is the first to show how aquaculture is not only directly affecting marine predators but could also indirectly affect their social structure and behaviour.  相似文献   
283.
Hormones play a central role in the physiology and behaviour of animals. The recent development of noninvasive techniques has increased information on physical and social states of individuals through hormone measurements. The relationships among hormones, life history traits and behaviours are, however, still poorly known. For the first time, we evaluated natural winter glucocorticoid and testosterone levels in young ungulates in relation to winter progression, diet quality and social rank. Overwinter, levels of glucocorticoid and testosterone decreased, possibly due to the decline of fawns’ body mass. The relationships between hormone levels and diet quality were surprising: Fawns fed the control diet presented higher glucocorticoid and lower testosterone levels then fawns fed the poor diet, suggesting that control fawns faced a higher nutritional stress than those on the poor diet. Similarly to other studies on social mammals, we found no relationship between faecal glucocorticoid levels and social rank, suggesting that social stress was similar for dominant and subordinate fawns during winter. Testosterone levels were not correlated to social rank as found previously in groups of individuals forming stable social hierarchies and maintaining stable dominance relationships. The simultaneous suppression of glucocorticoid and testosterone levels suggests for the first time that young ungulates present a hormonal strategy to prevent fast depletion of limited proteins and fat resources during winter.  相似文献   
284.
Infectious processes in a social group are driven by a network of contacts that is generally structured by the organization arising from behavioral and spatial heterogeneities within the group. Although theoretical models of transmission dynamics have placed an overwhelming emphasis on the importance of understanding the network structure in a social group, empirical data regarding such contact structures are rare. In this paper, I analyze the network structure and the correlated transmission dynamics within a honeybee colony as determined by food transfer interactions and the changes produced in it by an experimental manipulation. The study demonstrates that widespread transmission in the colony is correlated to a lower clustering coefficient and higher robustness of the social network. I also show that the social network in the colony is determined by the spatial distribution of various age classes, and the resulting organizational structure provides some amount of immunity to the young individuals. The results of this study demonstrates how, using the honeybee colony as a model system, concepts in network theory can be combined with those in behavioral ecology to gain a better understanding of social transmission processes, especially those related to disease dynamics.  相似文献   
285.
Theory predicts that frequent dyadic association should promote cooperation through kin selection or social tolerance. Here we test the hypothesis that sex differences in the strength and stability of association preferences among free-ranging chimpanzees conform to sex differences in cooperative behavior. Using long-term data from the Kanyawara chimpanzee (Pan troglodytes schweinfurthii) community (Kibale National Park, Uganda), we calculated indices of intra-sexual dyadic association over a 10-year period. We found that (1) male–male dyads had significantly stronger association indices than female–female dyads, (2) the pattern of association preferences in both sexes changed little over the entire study period, and (3) when comparing periods with different alpha males, changes in association strength were more frequent among males. These results demonstrate that both the strength and stability of association patterns are important components of social relationships. Male chimpanzees, which are characterized by frequent cooperation, had association preferences that were both strong and stable, suggesting that forming long-term bonds is an important dominance strategy. However, the fact that male association patterns were sensitive to upheaval in the male dominance hierarchy suggests that males also take advantage of a changing social climate when choosing association partners. By contrast, the overall strength of female associations was relatively weak. Female association preferences were equally stable as males’; however, this reflected a dyad’s tendency to be found in the same party rather than to associate closely within that party. Therefore, in this community, female association patterns appear to be more a consequence of individual ranging behavior rather than a correlate of cooperation.  相似文献   
286.
In 2016, Swedish climate reporting declined in quantity and shifted focus somewhat from climate change as such to the harmful climate impacts of meat consumption. The latter prompted discussions in social media—an increasingly important forum for public debate but infrequently studied in environmental communication research. Despite strong evidence that a meat and dairy-based diet is harmful for the environment, meat consumption is increasing, and this qualitative study aims to—through the lens of social representation theory—contribute knowledge about how livestock production is legitimized in everyday discourse on Facebook. The article identifies representations that legitimize livestock production through polarization between (1) livestock production and other (environmental) issues, (2) environmentally “good” and “bad” countries, and (3) “reliable” and “unreliable” information. It concludes by discussing the influence of national ideology on the legitimization of livestock production and the potential of social media to counter the post-politicization of environmental issues.  相似文献   
287.
This article explores individual and community action taken in response to perceived environmental risks by investigating the determinants of environmental action across a range of action types. A conceptual framework is first presented, which provides a foundation for investigating the role of local compositional (i.e., individual characteristics), contextual (i.e., neighborhood environment), and collective (i.e., social networks) factors in environmental action. To test the utility of the conceptual framework, a quantitative survey was administered to a random sample of households (n = 512) in Hamilton, Canada. The results suggest that the predictors of environmental action vary by action type (i.e., personal change, individual civic action, and cooperative civic action), and that factors related to perceived environmental exposure and social capital generally play a stronger, more consistent role in civic environmental action than sociodemographic or neighborhood factors. The results underscore the role of social connection in responses to perceived environmental risks.  相似文献   
288.
Large-scale infrastructural developments in rural areas often impose significant direct and indirect impacts on environment and people. The Three Gorges Project to dam the Yangtze River in China will create a huge reservoir, inundate farmlands and villages, and incur large-scale resettlement. The concurrent de-farming program to reforest marginal farmlands on steep slopes imposes additional stresses on local people. This study evaluates the ecological and economic adjustments in rural areas affected by both projects, and explores villagers’ knowledge, attitudes, perceptions, and expectations vis-à-vis the drastic changes. Eleven villages in Yunyang County in Sichuan Province, stratified into three zones based on topography and agriculture, were assessed by field studies, questionnaire surveys, maps, satellite imagery, and census and government reports. Multiple regressions identified predictors for 17 dependent variables. Spatial variations in the difficult terrain imposed zone-differentiated agricultural constraints, ecological impacts, and human responses. The dominant farming population—mainly young adults working as migrant laborers in cities—has adopted some nonagricultural work to supplement incomes. Expected per-capita standardized farmland (SF) exceeded threshold SF, which surpasses existing SF. Motivations to reclaim more farmlands, de-farm marginal lands, and become migrant laborers were explained by different multiple-regression predictors. Reduction in farmland stock by inundation and de-farming, aggravated by unwillingness towards nonlocal resettlement, would impose ecological pressures and stimulate demands for nonfarming incomes. Common anticipation of better future income and occupation has been subdued by unfavorable feedbacks from early relocatees. Future environmental and landscape changes are hinged upon changing human responses. Government policies could be informed by research findings to match economic, ecological, and social realities.  相似文献   
289.
Demographic change and economic decline produce modified urban land use pattern and densities. Compared to the beginning of the 90s after the German reunification, nowadays massive housing and commercial vacancies followed by demolition and perforation come to pass in many cities of the former GDR. In consequence, a considerable surplus of urban brownfields has been created. Furthermore, the decline in the urban fabric affects social infrastructure and urban greenery of local neighbourhoods. Here, urban planning enters into ‘uncharted territory’ since it needs to assess the socio-environmental impact of shrinkage.In order to carry out such an evaluation quantitatively, a multi-criteria assessment scheme (MCA) was developed and applied. Firstly, we identified infrastructure and land use changes related to vacancy and demolition. Secondly, demolition scenarios for the coming 20 years were applied in order to give an idea for a long-term monitoring approach at the local district level. A multi-criteria indicator matrix quantifies the socio-environmental impact on both urban greenery and residents. Using it, we set demolition scenarios against urban ‘quality of life’ targets. Empirical evidence comes from Leipzig, in eastern Germany, a representative case study for urban shrinkage processes.The results show that shrinkage implies socio-environmental changes of residential livelihoods, however, does not simply increase or decrease the overall urban quality of life. The integrated assessment of all indicators identifies environmental and social opportunities, as well as the challenges a shrinking city is faced with.  相似文献   
290.
Females of many cercopithecine primates live in stable dominance hierarchies that create long-term asymmetries among sets of female relatives (matrilines) in access to limiting resources and shelter from psychosocial stress. Rank-related differences in fitness components are widely documented, but their causes are unclear. Predicted breeding values from an animal model for female age of first reproduction are used to discriminate between shared additive genetic and shared environmental effects among the members of matrilines in a population of free-ranging rhesus macaques (Macaca mulatta). While age of first reproduction has a modest heritability (≈0.2), breeding values are distributed in a largely random fashion among matrilines and contribute little to the observed rank-related differences in average age of first reproduction. These results support the long-held, but previously unverified, contention that rank-related life history differences in female cercopithecine primates are the result of environmental rather than genetic differences among them.  相似文献   
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