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531.
M. B. McEachern John M. Eadie Dirk H. Van Vuren 《Behavioral ecology and sociobiology》2007,61(9):1459-1469
We used DNA microsatellites to investigate temporal and spatial patterns of local genetic differentiation and relatedness
in a solitary mammal, the dusky-footed woodrat (Neotoma fuscipes). Patterns of genetic variation were measured relative to spatial clusters, or neighborhoods, of woodrats. We detected significant genetic differentiation among woodrat neighborhoods in two populations spanning multiple
habitat types and densities. Estimates of θ
ST
among neighborhoods ranged 0.034–0.075 and were comparable to levels reported in social mammals. Genetic differentiation
at such a local scale is noteworthy because it occurred in the absence of any physical barriers to gene flow, suggesting that
the patterns observed are linked to the nonrandom patterns of mating and dispersal that characterize woodrat social structure.
Genetic differentiation and relatedness among neighborhoods were even higher when only resident females were analyzed. These
results are consistent with a pattern of female philopatry and male-biased dispersal in woodrats. Geographic distance and
relatedness were inversely correlated in adult females at intermediate densities, but not at low densities. Nonetheless, matrilineal
genetic structure was apparent even at low woodrat densities based on estimates of θ
ST
among neighborhoods of resident females that were significantly greater than zero and consistently greater than estimates
including all individuals. In summary, this study demonstrates a matrilineal genetic structure in dusky-footed woodrats. In
addition, our results support the idea that intermediate densities may be better at facilitating the formation of spatial
kin clusters than either extreme.
An erratum to this article can be found at 相似文献
532.
Smita Misra 《Natural resources forum》2000,24(4):285-295
This study explores the possibility of collective action as an alternative option for reducing water pollution for a cluster of small-scale industries. A case study of the Nandesari Industrial Estate in Gujarat, India, demonstrates the roles played by different agents, such as affected parties, polluters, non-governmental organizations, regulators and the court. The study empirically estimates the 'benefits' and 'costs' of water pollution abatement for a cluster of 250 small-scale industries at Nandesari, and uses these estimates for a social cost-benefit analysis. Benefits are estimated using the contingent valuation method, with a 'willingness to accept' format for the rural areas, and a 'willingness to pay' format for the urban area of the nearby Vadodara city. The article considers costs of command and control, market-based solutions and the option of common effluent treatment as alternative scenarios. It discusses how collective action and joint abatement at a common effluent treatment plant (CETP) by the 250 industries efficiently comply with the State Pollution Control Board norms, which had not been possible for the factories acting individually over the last 20 years. Finally, a detailed social cost-benefit analysis has been undertaken to estimate the net present social benefits with and without CETP. The cost-benefit analysis shows the economic advantage and social desirability of 'collective action' (joint treatment with CETP institutional arrangement) for water pollution abatement with respect to all possible scenarios comprising shadow prices of investment, foreign exchange, unskilled labour and equity considerations. 相似文献
533.
自然灾害对社会的影响:以1920年北方大旱为例 总被引:2,自引:1,他引:2
本文通过1920年我国北方五省大旱对社会影响的分析,提出了自然灾害对社会影响顺序的基本模式,讨论了社会对灾害的放大与缩小等问题。 相似文献
534.
Socially dominant males often signal their status to rival males and/or females. We tested the hypotheses that Lacerta monticola femoral gland secretions and copulatory plugs convey chemical information about male identity and dominance status. We estimated male dominance status by staging male–male agonistic encounters in a neutral arena. We then conducted two experiments to compare male tongue-flick behavior toward chemical stimuli consisting of cotton swabs bearing (1) deionized water (control), the lizard’s own femoral secretions, and the femoral secretions of another male and (2) phosphate-buffered saline solution (control), the lizard’s own plug products, and the plug products of another male. Results indicate that males discriminated their own femoral secretions and plugs from those of other males. They also discriminated morphological attributes of other males that were associated with dominance status based on chemical cues arising from femoral secretions and discriminated the dominance status of other males based on chemical cues arising from the plugs. Femoral secretions that convey information about male identity and dominance status may be hypothesized to function in the establishment of L. monticola dominance hierarchies through scent-marking of territories. We suggest that copulatory plugs and femoral secretions may allow males to scent-mark the female body and postulate that this behavior may influence male and female reproductive decisions under selective pressures of sperm competition. 相似文献
535.
SOCPROG programs: analysing animal social structures 总被引:2,自引:1,他引:1
Hal Whitehead 《Behavioral ecology and sociobiology》2009,63(5):765-778
SOCPROG is a set of programs which analyses data on animal associations. Data usually come from observations of the social
behaviour of individually identifiable animals. Associations among animals, sampling periods, restrictions on the data and
association indices can be defined very flexibly. SOCPROG can analyse data sets including 1,000 or more individuals. Association
matrices are displayed using sociograms, principal coordinates analysis, multidimensional scaling and cluster analyses. Permutation
tests, Mantel and related tests and matrix correlation methods examine hypotheses about preferred associations among individuals
and classes of individual. Weighted network statistics are calculated and can be tested against null hypotheses. Temporal
analyses include displays of lagged association rates (rates of reassociation following an association). Models can be fitted
to lagged association rates. Multiple association measures, including measures produced by other programs such as genetic
or range use data, may be analysed using Mantel tests and principal components analysis. SOCPROG also performs mark-recapture
population analyses and movement analyses. SOCPROG is written in the programming language MATLAB and may be downloaded free
from the World Wide Web. 相似文献
536.
Barbara Schröter Bettina Matzdorf Isabel Hackenberg Jennifer Hauck 《Local Environment》2018,23(6):635-651
While in many cases the benefits of ecosystem services (ES) can be enjoyed on different scales, the provision of ES requires engagement and commitment at the local scale. Therefore, the local level becomes important when thinking about compensation schemes or payments for ecosystem services (PES) as an approach to managing ES. The difficult task of bringing together different actors and institutions at different scales for specific conservation projects at the local level often remains in the hands of intermediaries. In this paper, we investigate the role of a civil society organisation (CSO) as an intermediary organisation in a PES scheme, the Community Blue Carbon Project (CBCP) in Costa Rica. To assess the role of intermediaries in a PES scheme, we rely on social network analysis and examine the position and role of the intermediary organisation. Based on Net-Map interviews, which is an interview-based mapping tool that helps people understand, visualise, discuss and improve situations in which many different actors influence outcomes, we find that the intermediary organisation in the CBCP is composed of several institutional and individual intermediaries who create both formal networks for connecting the international to the local level and informal networks for creating trusting relationships among the actors. Different spatial levels are reflected within the CSO’s organisational structure, and the CSO mitigates the distributional, procedural, recognition and contextual aspects of environmental justice. 相似文献
537.
美国曾经在环境保护和治理污染上做出了卓越的成绩,但是如今环境议题成为撕裂美国的重要议题。美国的共和党和民主党在环境议题上互相牵制,难以达成共识。最近,美国特朗普总统宣布退出应对气候变化的《巴黎协定》就是这种分歧的表现。但当美国1970年代开始环境立法治理污染的时候,美国社会上下和两大党之间高度一致。在此后,因为环境思想上的差异和代际转变,政党斗争、选举体制、利益集团等多方面原因,美国不同政治势力在环境议题上越发分裂。美国在环境议题上的分歧对中国如今解决环境问题有重要的启示意义:首先,现在我国社会上下一致应对环境问题的广泛共识很宝贵,应该抓住难得的机遇期,为未来环境治理积极立法,留下宝贵法治遗产。另一方面,随着人们在环境议题上的利益变得多元,中国应该在环境治理上整合各方面利益,防止中国未来的环保事业被利益集团绑架。最后,中国应该明确环境议题的概念远远大于治理污染,为未来环境事业扩展空间。 相似文献
538.
落实《水污染防治行动计划》投融资思路与建议——对《水污染防治行动计划》的解读 总被引:1,自引:0,他引:1
创新、拓宽水环境保护领域投融资渠道,是落实水污染防治行动计划、保障国家水安全的关键环节。研究结论表明,水污染防治领域成熟稳定的财政资金投入机制匮乏、中小环保企业水环境治理项目融资存在制约瓶颈、社会资本水污染治理投入盈利机制不健全等是关键制约因素。鉴于此,文章提出了落实《水污染防治行动计划》的投融资思路和具体建议:整合设立水污染防治专项资金以建立政府常态化投入机制,设立政府主导的环境保护基金以发挥财政资金引导作用,建立社会资本水污染防治项目资金投入回报机制以吸引社会资本投入,创新环境金融服务、发挥市场融资作用以提升水污染治理企业或项目融资能力。 相似文献
539.
This paper proposes to define sustainability in terms of leaving it possible for future generations to sustain certain defined targets. It is shown that variants of genuine savings and the ecological footprint can then serve as indicators of sustainability. The link between sustainability and intergenerational welfare is examined, and it is shown how to incorporate indicators of sustainability into a social welfare measure, including risk in the analysis. 相似文献
540.
In urban areas, buried gas pipeline leakages could potentially cause numerous casualties and massive damage. Traditional static analysis and dynamic probability-based quantitative risk assessment (QRA) methods have been widely used in various industries. However, dynamic QRA methods combined with probability and consequence are rarely used to evaluate gas pipelines buried in urban areas. Therefore, an integrated dynamic risk assessment approach was proposed. First, a failure rate calculation of buried gas pipelines was performed, where the corrosion failure rate dependent on time was calculated by integrating the subset simulation method. The relationship between failure probability and failure rate was considered, and a mechanical analysis model considering the corrosion growth model and multiple loads was used. The time-independent failure rates were calculated by the modification factor methods. Next, the overall evolution process from pipeline failures to accidents was proposed, with the accident rates subsequently updated. Then, the consequences of buried gas pipeline accidents corresponding to the accident types in the evolution process were modeled and analyzed. Finally, based on the above research, dynamic calculation and assessment methods for evaluating individual and social risks were established, and an overall application example was provided to demonstrate the capacity of the proposed approach. A reliable and practical theoretical basis and supporting information are provided for the integrity and emergency management of buried gas pipelines in urban areas, considering actual operational conditions. 相似文献