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331.
D. S. Pope 《Behavioral ecology and sociobiology》2000,47(6):432-437
Many territorial advertisement signals are thought to be dual-function signals, directed to both rival male and receptive
female conspecifics. However, few studies have tested this assumption by examining whether in fact both sexes are likely to
elicit signaling behavior from territorial males. In this study, I experimentally manipulated the social context of male sand
fiddler crabs (Uca pugilator) to investigate the effect of different audiences on the performance of the claw-waving display, a territorial signal that
is often presumed to be directed to both males and females. To test whether males perform this signal to both audiences, I
measured the frequency of waving behavior by focal males when housed in field enclosures alone, with only males, with only
females, or with both males and females. Focal males waved at a low frequency when alone, and the presence of males had no
effect on their level of waving. However, in the presence of females, focal males showed a significantly higher level of waving,
whether or not males were also present. In addition, there was no association between fighting and waving behavior. This experiment
provides evidence that from the perspective of the signaling male, the claw-waving display of U. pugilator is not a dual-function signal but rather is primarily directed to receptive females.
Received: 16 December 1999 / Received in revised form: 1 February 2000 / Accepted: 19 February 2000 相似文献
332.
There is a growing recognition that scientific and social conflict pervades invasive species management, but there is a need for empirical work that can help better understand these conflicts and how they can be addressed. We examined the tensions and conflicts facing invasive Asian carp management in Minnesota by conducting 16 in-depth interviews with state and federal agency officials, academics, and stakeholders. Interviewees discussed the tensions and conflicts they saw impacting management, their implications, and what could be done to address them. We found three key areas of conflict and tension in Asian carp management: 1) scientific uncertainty concerning the impacts of Asian carp and the efficacy and non-target effects of possible management actions; 2) social uncertainty concerning both the lack of societal agreement on how to respond to Asian carp and the need to avoid acting from apathy and/or fear; and 3) the desired approach to research and management – whether it is informed by “political need” or “biological reality”. Our study of these tensions and conflicts reveals their importance to Asian carp management and to invasive species management, more broadly. We conclude with a discussion of possible ways to address these areas of tension and conflict, including the potential of deliberative, participatory approaches to risk-related decision making and the need to productively engage with apathy and fear. 相似文献
333.
People matter: The importance of social capital in the co-management of natural resources 总被引:2,自引:0,他引:2
Co‐management involves the shared administration of natural resources by two or more parties. This study examines the role of social capital in the process of developing co‐management in three river corridors in Canada. Qualitative analysis reveals that social capital acts as a catalyst helping groups to progress through the stages of the co‐management process. Forms of social capital (bridging and bonding) are identified that advance and/or inhibit the development of co‐management. The article reaffirms the need to expand the institutional basis for natural resource management and provides empirical evidence that social capital plays a fundamental role in developing co‐management. In conclusion, the article suggests that resource agencies need to recognize the value of social capital and the necessity for government representatives to be informed of and practiced in these skills, if they are to engage meaningfully with the civilian population. 相似文献
334.
Mikael Hake 《Behavioral ecology and sociobiology》1996,39(2):71-76
Relationships between social status and levels of body reserves stored by members of greenfinch (Carduelis chloris) flocks in winter were investigated. In addition, the adjustment of reserves by birds of different rank to experimental changes
in food predictability and to changed weather conditions were examined. Birds with low social status carried overall larger
body reserves than high-ranked birds. The results of the experiments suggest that this was mainly because subordinates, due
to their low priority to food access, perceived future foraging success as less predictable than dominants. In response to
severe weather, which probably increased the risk of starvation for birds, dominants temporarily increased their reserves
more than subordinates. This response also indicated that birds with low social status carried larger reserves than high-ranked
birds, and demonstrated that dominants could increase food intake when there was a risk of energetic shortfall. The results
suggest that fattening strategies in greenfinches depend on social status. In winter, subordinates may be forced to carry
larger reserves than dominants to safeguard against social constraints in access to food during critical times. As body reserves
may be costly to carry and acquire, this should reduce the probability of surviving the winter for subordinates compared to
dominants.
Received: 2 March 1995/Accepted after revision: 13 April 1996 相似文献
335.
基于AHP和向量模法的宜昌市水环境承载力研究 总被引:4,自引:0,他引:4
基于宜昌市水环境现状,从水资源、水生态、社会经济3个方面考察水环境承载力,构建了宜昌市水环境承载力指标体系,选取对数函数作为单项指标的承载度模型,采用层次分析法计算各个指标的权重,基于统计年鉴资料和当地的发展规划,运用向量模法对2005-2020年的宜昌市水环境承载力进行评价和分析。结果表明,近几年宜昌市水环境整体上处于中等偏上水平,承载力值维持在0.55左右,并且该状态将一直维持到2015年,但伴随着宜昌市社会经济的发展,人口规模的扩张,水资源因子将会是宜昌市水环境承载力的限制因素,可以预知,如果宜昌市保持现有经济结构和发展速度,2020年宜昌市水环境承载力值将有所下降,届时水环境问题势必影响到宜昌市生态环境、社会经济和人民生活。 相似文献
336.
Groundwater is a key resource for global agricultural production but is vulnerable to a changing climate. Given significant uncertainty about future impacts, bottom-up approaches for developing adaptive capacity are a more appropriate paradigm than seeking optimal adaptation strategies that assume a high ability to predict future risks or outcomes. This paper analyses the groundwater management practices adopted at multiple scales in East Anglia, UK, to identify wider lessons for developing adaptive capacity within groundwater management. Key elements are (1) horizontal and vertical integration within resource management; (2) making better use of water resources, at all scales, which vary in space and time; (3) embedding adaptation at multiple scales (from farm to national) within an adaptive management framework which allows strategies and management decisions to be updated in the light of changing understanding or conditions; (4) facilitating the ongoing formation through collective action of local Water Abstractor Groups; (5) promoting efficient use of scarce water resources by these groups, so as to increase their power to negotiate over possible short-term license restrictions; (6) controlling abstractions within a sustainable resource management framework, whether at national (regulatory) or at local (Abstractor Group) scales, that takes account of environmental water needs; and (7) reducing non-climate pressures which have the potential to further reduce the availability of usable groundwater. 相似文献
337.
Se‐Yeun Lee Alan F. Hamlet Carolyn J. Fitzgerald Stephen J. Burges 《Journal of the American Water Resources Association》2011,47(1):81-92
Lee, Se‐Yeun, Alan F. Hamlet, Carolyn J. Fitzgerald, and Stephen J. Burges, 2011. Methodology for Developing Flood Rule Curves Conditioned on El Niño‐Southern Oscillation Classification. Journal of the American Water Resources Association (JAWRA) 47(1):81‐92. DOI: 10.1111/j.1752‐1688.2010.00490.x Abstract: Regional climate varies on interannual and decadal time scales that in turn affect annual streamflows, flood risks, and reservoir storage deficits in mid‐summer. However, these variable elements of the climate system are generally not included in water resources operating policies that attempt to preserve a balance between flood risk and other water resources system objectives. A methodology for incorporating El Niño‐Southern Oscillation (ENSO) information in designing flood control curves is investigated. An optimization‐simulation procedure is used to develop a set of ENSO‐conditioned flood control rule curves that relate streamflow forecasts to flood control evacuation requirements. ENSO‐conditioned simulated flood risk and storage deficits under current operating policy are used to calibrate a unique objective function for each ENSO classification. Using a case study for the Columbia River Basin, we demonstrate that ENSO‐conditioned flood control curves constructed using the optimization‐simulation procedure consistently reduce storage deficits at a number of interrelated projects without increasing flood risk. For the Columbia Basin, the overall improvements in reservoir operations are relatively modest, and (in isolation) might not motivate a restructuring of flood control operations. However, the technique is widely applicable to a wide range of water resources systems and/or different climate indices. 相似文献
338.
Laien He Gregory V. Wilkerson 《Journal of the American Water Resources Association》2011,47(6):1298-1316
He, Laien and Gregory V. Wilkerson, 2011. Improved Bankfull Channel Geometry Prediction Using Two‐Year Return‐Period Discharge. Journal of the American Water Resources Association (JAWRA) 47(6):1298–1316. DOI: 10.1111/j.1752‐1688.2011.00567.x Abstract: Bankfull discharge (Qbf) and bankfull channel geometry (i.e., width, Wbf; mean depth, Dbf; and cross‐section area, Abf) are important design parameters in stream restoration, habitat creation, mined land reclamation, and related projects. The selection of values for these parameters is facilitated by regional curves (regression models in which Qbf, Wbf, Dbf, and Abf are predicted as a function of drainage area, Ada). This paper explores the potential for the two‐year return‐period discharge (Q2) to improve predictions of Wbf, Dbf, and Abf. Improved predictions are expected because Q2 estimates integrate the effects of basin drainage area, climate, and geology. For conducting this study, 29 datasets (each representing one hydrologic region) spanning 14 states in the United States were analyzed. We assessed the utility of using Q2 by comparing statistical measures of regression model performance (e.g., coefficient of determination and Akaike’s information criterion). Compared to using Ada, Q2 is shown to be a “clearly superior” predictor of Wbf, Dbf, and Abf, respectively, for 21, 13, and 25% of the datasets. By contrast, Ada yielded a clearly superior model for predicting Wbf, Dbf, and Abf, respectively, for 0, 0, and 14% of the datasets. Our conclusion is that it alongside with developing conventional regional curves using Ada it is prudent to develop regional curves that use Q2 as an independent variable because in some cases the resulting model will be superior. 相似文献
339.
This study examined the relationship between exteriors of police department facilities and participants’ ratings of the buildings’ authority, professionalism, and approachability. After a pilot study, research was conducted with 122 participants who were undergraduate students from a small, liberal arts college in the Northeast. On each of three characteristics (authority, professionalism, and approachability), participants rated 16 color images of police departments located in the United States. The façade ratings for each characteristic were then categorized into factors through factor analyses. There were three factors for authority (Ineffectual, Strong, and Outdated); three for professionalism (Unskilled, Non-traditional, and Governmental); and four for approachability (Uninviting, Accessible, Public, and Impenetrable). The results were compared to participants’ scores on the Right-Wing Authoritarianism Scale (Altemeyer, 1981) and the Social Dominance Orientation scale (Sidanius & Pratto, 1999). Although the primary goal for the study was to determine whether there are consistent responses to police department exteriors, it was hypothesized that the façade ratings would relate to the authoritarianism ratings, with more authoritarian people expected to rate the façades higher in authority. Although this hypothesis was not supported, significant findings were related to gender. Applications to architectural design are discussed. 相似文献
340.
Anke Fischer Fransje Langers Birgit Bednar-Friedl Nicoleta Geamana Ketil Skogen 《Journal of environmental psychology》2011,31(2):118-128
Despite a growing body of literature on public views on biodiversity and nature, our understanding of public attitudes towards animal and plant species is still rudimentary. This study investigates mental representations, constituted by beliefs, of three types of species (a large mammal, a spider and a non-native plant), and explores their links with cultural factors such as value orientations and cultural capital, in order to better understand attitudes towards these species.We conducted a survey in eight sites across Europe (n = 2378) and found strong relationships between beliefs about species, in particular with regard to their harmlessness, value and previous population change, and the desirability of an increase in this species. Other beliefs, such as perceived nativeness, were less influential. We discuss how respondents combined beliefs to mental representations of species, and show how representations are related to species-independent factors that tap respondents’ cultural context, such as socially shared value orientations and education. 相似文献