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John A. Kronenberger Jill C. Gerberich Sarah W. Fitzpatrick E. Dale Broder Lisa M. Angeloni W. Chris Funk 《Conservation biology》2018,32(4):838-848
Human land use is fragmenting habitats worldwide and inhibiting dispersal among previously connected populations of organisms, often leading to inbreeding depression and reduced evolutionary potential in the face of rapid environmental change. To combat this augmentation of isolated populations with immigrants is sometimes used to facilitate demographic and genetic rescue. Augmentation with immigrants that are genetically and adaptively similar to the target population effectively increases population fitness, but if immigrants are very genetically or adaptively divergent, augmentation can lead to outbreeding depression. Despite well‐cited guidelines for the best practice selection of immigrant sources, often only highly divergent populations remain, and experimental tests of these riskier augmentation scenarios are essentially nonexistent. We conducted a mesocosm experiment with Trinidadian guppies (Poecilia reticulata) to test the multigenerational demographic and genetic effects of augmenting 2 target populations with 3 types of divergent immigrants. We found no evidence of demographic rescue, but we did observe genetic rescue in one population. Divergent immigrant treatments tended to maintain greater genetic diversity, abundance, and hybrid fitness than controls that received immigrants from the source used to seed the mesocosms. In the second population, divergent immigrants had a slightly negative effect in one treatment, and the benefits of augmentation were less apparent overall, likely because this population started with higher genetic diversity and a lower reproductive rate that limited genetic admixture. Our results add to a growing consensus that gene flow can increase population fitness even when immigrants are more highly divergent and may help reduce uncertainty about the use of augmentation in conservation. 相似文献
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Reiter Dana Meyer Wayne Parrott Lael Baker Douglas Grace Peter 《Regional Environmental Change》2018,18(4):1173-1184
Regional Environmental Change - There is a need to increase regional and community level action towards adaptation to climate change. Natural resource managers and planners have to make challenging... 相似文献
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Lisa Ernoul 《国际发展与全球生态学杂志》2013,20(4):228-233
A perception study of the impacts that a new beach resort has, and will have, on the resident population in the northeast of Morocco was implemented during the construction phase of the resort. The residents have felt the impacts on local development, incomes, quality of life and the environment, and expressed their perception of how the opening of the new site will continue to impact their community. The study shows differences concerning the type of impact according to each professional sector. Despite the different perceptions, residents seem united in their overall concerns and fears about the how the new beach resort will impact the environment. 相似文献
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John A. Wagner III Stephen E. Humphrey Christopher J. Meyer John R. Hollenbeck 《组织行为杂志》2012,33(7):946-963
This study revisits the commonplace research conclusion that greater team member collectivism, as opposed to individualism, is associated with higher levels of individual‐level performance in teams. Whereas this conclusion is based on the assumption that work in teams consists exclusively of tasks that are shared, typical teamwork also includes tasks that are individualized. Results of a laboratory study of 206 participants performing a mix of individualized and shared tasks in four‐person teams indicate that heterogeneous combinations of individualism and collectivism are associated with higher levels of team member performance, measured as quantity of output, when loose structural interdependence enables individual differences in individualism–collectivism to exert meaningful effects. These results support the modified conclusion that a combination of individualism and collectivism is associated with higher levels of member performance in teams under typical work conditions; that is, conditions in which the tasks of individual members are both individualized and shared. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Does efficient irrigation technology lead to reduced groundwater extraction? Empirical evidence 总被引:1,自引:0,他引:1
Encouraging the use of more efficient irrigation technology is often viewed as an effective, politically feasible method to reduce the consumptive use of water for agricultural production. Despite its pervasive recommendation, it is not clear that increasing irrigation efficiency will lead to water conservation in practice. In this paper, we evaluate the effect of a widespread conversion from traditional center pivot irrigation systems to higher efficiency dropped-nozzle center pivot systems that has occurred in western Kansas. State and national cost-share programs subsidized the conversion. On an average, the intended reduction in groundwater use did not occur; the shift to more efficient irrigation technology has increased groundwater extraction, in part due to shifting crop patterns. 相似文献
430.
When a no‐notice emergency prompts an evacuation, family members in different locations throughout a city may unite so that they can evacuate as a group. This paper draws on data from more than 300 interviews conducted in the metropolitan area of Chicago, Illinois, United States. The study uses discrete choice models to analyse the expectations of respondents regarding whether their likely plans for evacuation involve gathering spouses, parents, adult‐age children, and/or non‐family members. In addition, it addresses the matter of whether respondents plan to reunite with family members at home. Individuals' access to a personal car is the dominating factor in predicting whether respondents plan to gather a spouse. Being the parent of a child under the age of 18 years increases the tendency to report planning to reunite with family members at home. Both commute mode and car availability are not significantly associated with plans to reunite at home. 相似文献