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191.
The lack of knowledge regarding social diversity in the Wildland Urban Interface (WUI) or an in-depth understanding of the ways people living there interact to address common problems is concerning, perhaps even dangerous, given that community action is necessary for successful wildland fire preparedness and natural resource management activities. In this article, we lay out the knowledge and preliminary case study evidence needed to begin systematically documenting the differing levels and types of adaptive capacity WUI communities have for addressing collective problems such as wildland fire hazard. In order to achieve this end, we draw from two theoretical perspectives encompassing humans' interactions with their environment, including (1) Kenneth Wilkinson's interactional approach to community, (2) and certain elements of place literature. We also present case study research on wildfire protection planning in two drastically different California communities to illustrate how social diversity influences adaptive capacity to deal with hazards such as wildland fire. These perspectives promote an image of the WUI not as a monolithic entity but a complex mosaic of communities with different needs and existing capacities for wildland fire and natural resource management.  相似文献   
192.
We sought to understand why a social, desert rodent, the great gerbil, Rhombomys opimus, expends energy and possible risk of predation by footdrumming and vocalizing in the presence of a diversity of terrestrial predators: snakes, monitor lizards, polecats, foxes, and humans. Behavioral observations, human approaches, and experiments with tethered predators revealed that both male and female gerbils called and footdrummed in the presence of offspring, close relatives, and potential mates. Because adults called more often when pups were present, and solitary gerbils seldom gave an alarm, the alarm behavior probably warns conspecifics, especially vulnerable offspring, of potential danger. We also found that gerbils altered alarm behavior with the type of predator. They drummed more in the burrow when a dog that could not enter the burrow was present, and they drummed more out of the burrow in response to a snake that could enter the burrow. Gerbils vocalized and stood in an alert posture in response to all stimuli. The different footdrumming responses of gerbils to terrestrial predators seems related to the hunting style and type of risk posed by the predator, especially its ability to enter the burrow system. Received: 23 August 1999 / Received in revised form: 6 December 1999 / Accepted: 25 February 2000  相似文献   
193.
Sex ratios were bimodally distributed in a population of the monogynous and monandrous ant Leptothorax nylanderi during each of 3 study years. The population-wide investment ratios suggested worker control of sex allocation. Nest-level variation in the proportional investment in virgin queens was not affected by the presence or absence of a queen and only slightly by collecting year, but was correlated with nest size, total sexual investment and, unexpectedly, with differences in nestmate relatedness: small, low-investment nests and nests with several worker lineages produced male-biased sex ratios. Colonies containing several worker lineages arise from usurpation of mature colonies by unrelated founding queens and the fusion of unrelated colonies under strong nest site limitation. In contrast to facultatively polygynous and polyandrous species of social insects, where workers can maximize their inclusive fitness by adjusting sex ratios according to the degree of relatedness asymmetry, workers in mixed colonies of L. nylanderi do not benefit from manipulating sex allocation, as here relatedness asymmetries appear to be the same as in homogeneous colonies. Received: 7 December 1999 / Received in revised form: 29 February 2000 / Accepted: 13 March 2000  相似文献   
194.
从发达国家的经验来看,多元主体社会共治是环境保护和建设生态文明的有效途径,也是生态文明建设的必然趋势。本文以"绿色浙江"为例,重点分析了其在组织结构上的独特性,处理和政府、企业之间关系的巧妙性和平衡性,还分析了"绿色浙江"在环境保护项目中经常运用的公众参与机制、圆桌协商机制、舆论倒逼机制和服务外包机制等。最后,文章提出生态文明建设中社会共治的实现路径包括两个方面:环保组织要加强核心技术的开发和公益人才的培养,地方政府则要完善《中华人民共和国环境保护法》关于公众参与和信息公开的具体操作程序,扩大社会组织和市民群体参与本地生态文明建设的渠道和空间。  相似文献   
195.
A comprehensive approach for the evaluation of the economic feasibility of landfill mining (LFM) should take into account not only the direct costs and revenues for the private investor, but also the social benefits or costs (generally called externalities), in such a way that projects generating major social benefits (and no significant private revenues) are not overlooked.With a view to contributing to the development of a common framework for the evaluation of LFM projects, this paper presents the results of a case study where the issue of the assessment of social benefits from a LFM project is addressed. In particular, the Contingent Valuation Method is applied for the monetary assessment of the community-perceived benefits from the remediation of an old uncontrolled waste deposit by means of LFM and the conversion of the area into a park.Based on the results of a survey carried out on a random sample of people living near the old landfill, the economic values of the individual willingness to pay (WTP) for LFM and the subsequent creation of a public park were calculated and the correlations with the relevant variables (distance from the landfill site, age, income, sex, education level) assessed. The results were then suitably extended and the monetary value of the welfare increase of the whole population resident in the area and potentially affected both by LFM and the creation of the park was calculated.  相似文献   
196.
Summary To investigate the dynamics of the winter flock patch exploitation, feeding experiments were performed with 140 semi-tame, free-roaming greylag geese (Anser anser). Three different initial densities of barley were offered on a 50-m2 patch: low (1600 grains/m2), intermediate (3300/m2) and high (I 1500/m2). Goose numbers on the patch, peck rates, and frequencies of agonistic encounters and of alert postures were observed by scanning the flock and in focal individuals. At low and intermediate initial food densities, peck rates decreased with food density, whereas at high food density, peck rates decreased only slightly over the feeding bout. Agonistic interactions increased as food decreased. A switch from exploitation to interference competition occurred at a threshold of approximately 900 remaining grains per square meter. With high initial food density, agonistic encounters began to increase gradually after 20–30 min. The same general patterns were observed for frequency of alertness. Family members occupied the patch for the longest time periods. The family female and the offspring fed most intensely. The family gander however, fed significantly less but was more aggressive and vigilant than all other social categories. Solitary geese spent their time on the patch doing little else but feeding and were the first to leave. It seems that high-ranking families and low-ranking singles adopt different competitive strategies, the former being superior interference competitors whereas the latter are forced scramble competitors.This study is dedicated to the memory of Konrad Lorenz Correspondence to: K. Kotrschal  相似文献   
197.
Many impacts of Global Environmental Assessment (GEA) processes on policy processes, and the mechanisms underlying these impacts, remain underappreciated. In this research, we focus on the 5th Global Environment Outlook and the Working Group III contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Based on the perception of GEA process participants, we describe the mechanisms through which assessments create or alter interpersonal interactions which can affect the dissemination of ideas. In particular, we find that GEAs can contribute to framing international coordinative discourses in intergovernmental negotiations. This can be achieved by widening, improving and/or maintaining the active participation of policy actors in the discussions of global environmental risks and by creating the scientific foundations for intergovernmental negotiations. GEAs can also contribute to national coordinative discourses by facilitating reflexive learning amongst participants, empowering them to diffuse and translate global information, and by providing methodological guidance. They can contribute to national communicative discourses by reviving interest and awareness of the urgency to address environmental problems. In this way they provide powerful arguments for governmental societal actors to challenge or strengthen existing national coordinative discourses. Finally, GEAs can improve scientific discourses worldwide by enhancing the capacity of individual researchers to produce and communicate relevant research insights. This is achieved by participating in a learning exercise with an extended community of peers and policy actors. This article is part of a special issue on solution-oriented global environmental assessments.  相似文献   
198.
关于安全经济学的分析与探讨   总被引:1,自引:0,他引:1  
论述了安全经济学的概念、基础,及其在安全科学体系结构中的地位和作用,提出了研究的主要内容和方法。  相似文献   
199.
Data on langur (Presbytis entellus) populations were gathered from the literature to test the importance of three selective pressures in determining group size and composition: predation pressure, intergroup resource defense, and conspecific threat. There were no detectable difference in the size of groups in populations facing nearly intact predator communities compared to those populations where predators were severely reduced in number or absent, although there was a trend for the number of adult males per group to increase in areas with nearly intact predator communities. Using population density as an indirect measure of the frequency of intrusions into a group’s home range and thereby as an index of the demographic pressure favoring resource defense, we predicted that higher densities would result in larger defensive coalitions and higher numbers of females per group. This prediction was not upheld. Our third selective pressure, conspecific threat, encompasses those selective forces resulting from physical attack on females, infants, and juveniles. Our index of conspecific threat uses the number of non-group males divided by the number of bisexual groups, because in langurs, the major source of conspecific threat derives from non-group males who, following group take-over, kill infants, wound females, and expel juveniles from groups. This index of conspecific threat was strongly related to the mean number of resident females, was weakly related to the mean group size, but was not related to the number of males in the group. In addition, as predicted, populations with a high index of conspecific threat had higher levels of juvenile expulsion. These analyses were corroborated by a simulation model which used a computer-generated series of null populations to calculate expected slopes of immatures regressed on adult females. These randomly generated populations, matched to means and ranges of real populations, allowed us to determine if deviations of the observed slopes from the expected null slopes could be explained by variation in predation pressure, population density, or conspecific threat. We found no evidence that predation pressure was associated with decreases in immature survival in smaller groups, as would be predicted by the predation-avoidance hypothesis. We found no evidence that immature survival was compromised by small group size in high-density populations, as would be predicted by the resource-defense hypothesis. However, as the index of conspecific threat increased, groups with larger numbers of females were more successful than groups with fewer females in reducing mortality or expulsion of immatures. Overall, conspecific threat received the strongest support as a selective pressure influencing langur group size and composition, suggesting that this selective pressure should be evaluated more widely as a factor influencing composition of animal groups. Received: 23 January 1995/Accepted after revision: 18 February 1996  相似文献   
200.
重庆市江北地震灾害与社会经济影响   总被引:1,自引:1,他引:0  
本文表述了1989年11月20日发生在重庆市江北县的5.2和5.4级地震的受灾范围、人畜伤亡、地表破坏、建筑物损毁、各类生命线系统工程及设施机能破坏情况;分析、计算了地震造成的直接和间接经济损失;分析、研究了地震引起的各种社会、经济影响及社会问题。  相似文献   
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