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Sarah K. Jacobi Charles S. ReVelle Robert L. Pressey Justin C. Williams 《Environmental Modeling and Assessment》2007,12(2):91-103
We examine the irreplaceability of sites in the context of the species set covering problem and the maximal covering species
problem. We show that a succession of 0-1 programming problems can be solved to quickly determine the set of irreplaceable
sites. For the widely available Oregon data set, we find a general lack of trend in the number of irreplaceable sites with
the number of sites available for selection used. Moreover, we observe that irreplaceability at one level of resource may
not be a predictor of irreplaceability at a higher or a lower level of resource. Finally, we investigate the economic value
of irreplaceable sites by trial removals of those sites.
This paper is dedicated to the memory of Dr. Charles S. ReVelle. 相似文献
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Food and Environmental Virology - The U.S. FDA Food Safety Modernization Act Preventive Controls for Human Food Rule emphasizes the importance of an effective environmental monitoring (EM) program.... 相似文献
296.
Dyssegmental dysplasia,Silverman-Handmaker type: prenatal ultrasound findings and molecular analysis
297.
Prosecution of experts in the wake of disasters has emerged as common in the context of increasing social intolerance of risk. This paper examines expert blame using as a case study the decisions of engineers who operated Wivenhoe Dam during the Queensland floods in January 2011 and the criticisms of those decisions by the subsequent Commission of Inquiry. Our analysis draws on the literature on organisational safety, organisational learning and expertise to examine the relevance of the criteria against which the engineers were judged, the relevant competence of those who made this assessment and the broader implications of such exercises. Our analysis shows that lay judgements of expert practice can be misleading, as evidenced by the Commission of Inquiry’s misguided focus on procedural adherence. We argue that such inquiries—where the focus is on assigning blame—detract from opportunities to learn from incidents and can negatively impact on professional practices. If the aim is to make future disasters less likely, then inquiries that take this approach may be failing in this endeavour, or at least not maximising their contribution. 相似文献
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Oliver C. Stringham Adam Toomes Aurelie M. Kanishka Lewis Mitchell Sarah Heinrich Joshua V. Ross Phillip Cassey 《Conservation biology》2021,35(4):1130-1139
The unrivaled growth in e-commerce of animals and plants presents an unprecedented opportunity to monitor wildlife trade to inform conservation, biosecurity, and law enforcement. Using the internet to quantify the scale of the wildlife trade (volume and frequency) is a relatively recent and rapidly developing approach that lacks an accessible framework for locating relevant websites and collecting data. We produced an accessible guide for internet-based wildlife trade surveillance. We detailed a repeatable method involving a systematic internet search, with search engines, to locate relevant websites and content. For data collection, we highlight web-scraping technology as an efficient way to collect data in an automated fashion at regularly timed intervals. Our guide is applicable to the multitude of trade-based contexts because researchers can tailor search keywords for specific taxa or derived products and locations of interest. We provide information for working with the diversity of websites used in wildlife trade. For example, to locate relevant content on social media (e.g., posts or groups), each social media platform should be examined individually via the site's internal search engine. A key advantage of using the internet to study wildlife trade is the relative ease of access to an increasing amount of trade-related data. However, not all wildlife trade occurs online and it may occur on unobservable sections of the internet. 相似文献
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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