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271.
Conservation biologists recognize that a system of isolated protected areas will be necessary but insufficient to meet biodiversity objectives. Current approaches to connecting core conservation areas through corridors consider optimal corridor placement based on a single optimization goal: commonly, maximizing the movement for a target species across a network of protected areas. We show that designing corridors for single species based on purely ecological criteria leads to extremely expensive linkages that are suboptimal for multispecies connectivity objectives. Similarly, acquiring the least‐expensive linkages leads to ecologically poor solutions. We developed algorithms for optimizing corridors for multispecies use given a specific budget. We applied our approach in western Montana to demonstrate how the solutions may be used to evaluate trade‐offs in connectivity for 2 species with different habitat requirements, different core areas, and different conservation values under different budgets. We evaluated corridors that were optimal for each species individually and for both species jointly. Incorporating a budget constraint and jointly optimizing for both species resulted in corridors that were close to the individual species movement‐potential optima but with substantial cost savings. Our approach produced corridors that were within 14% and 11% of the best possible corridor connectivity for grizzly bears (Ursus arctos) and wolverines (Gulo gulo), respectively, and saved 75% of the cost. Similarly, joint optimization under a combined budget resulted in improved connectivity for both species relative to splitting the budget in 2 to optimize for each species individually. Our results demonstrate economies of scale and complementarities conservation planners can achieve by optimizing corridor designs for financial costs and for multiple species connectivity jointly. We believe that our approach will facilitate corridor conservation by reducing acquisition costs and by allowing derived corridors to more closely reflect conservation priorities.  相似文献   
272.
273.
A growing number of programs seek to facilitate species conservation using incentive-based mechanisms. Recently, a market-based incentive program for the federally endangered Golden-cheeked Warbler (Dendroica chrysoparia) was implemented on a trial basis at Fort Hood, an Army training post in Texas, USA. Under this program, recovery credits accumulated by Fort Hood through contracts with private landowners are used to offset unintentional loss of breeding habitat of Golden-cheeked Warblers within the installation. Critical to successful implementation of such programs is the ability to value, in terms of changes to overall species viability, both habitat loss and habitat restoration or protection. In this study, we sought to answer two fundamental questions: Given the same amount of change in breeding habitat, does the change in some patches have a greater effect on metapopulation persistence than others? And if so, can characteristics of a patch (e.g., size or spatial location) be used to predict how the metapopulation will respond to these changes? To answer these questions, we describe an approach for using sensitivity analysis of a metapopulation projection model to predict how changes to specific habitat patches would affect species viability. We used a stochastic, discrete-time projection model based on stage-specific estimates of survival and fecundity, as well as various assumptions about dispersal among populations. To assess a particular patch's leverage, we quantified how much metapopulation viability was expected to change in response to changing the size of that patch. We then related original patch size and distance from the largest patch to each patch's leverage to determine if general patch characteristics could be used to develop guidelines for valuing changes to patches within a metapopulation. We found that both the characteristic that best predicted patch leverage and the magnitude of the relationship changed under different model scenarios. Thus, we were unable to find a consistent set of relationships, and therefore we emphasize the dangers in relying on general guidelines to assess patch value. Instead, we provide an approach that can be used to quantitatively evaluate patch value and identify critical needs for future research.  相似文献   
274.
Ecological thresholds are abrupt changes of ecological state. While an ecological threshold is a widely accepted concept, most empirical methods detect them in time or across geographic space. Although useful, these approaches do not quantify the direct drivers of threshold response. Causal understanding of thresholds detected empirically requires their investigation in a multi-factor domain containing the direct drivers (often referred to as state space). Here, we present an approach to quantify thresholds from response surfaces modeled empirically in state space. We present two indices of shape attributes measured from response surfaces. The response surfaces are built using a regression method in state space. The indices are threshold strength (T) and diagonality (D). We use 48 simulated response surfaces of different shapes to test the efficacy of the indices in 3D. Our results show that T is sensitive to the steepness of the transition from one state to the next, with various forms of abrupt, centralized thresholds yielding the highest values among the simulated surfaces. D represents the orientation of the response surface or the simultaneous influence of more than one predictor in eliciting the response gradient. Strongly diagonal surfaces have the most diagonal surface area demonstrated by sharply undulating diagonal surfaces. Given that the success of T and D requires a regression method to accurately capture any shape of complex data structure, we also test the accuracy of empirical regression methods known to be tractable with complex data. We test classification and regression trees (CART), Random Forest, and non-parametric multiplicative regression (NPMR) for binary and continuous responses. We use the 48 simulated response surfaces to test the methods, and we find that prediction accuracy depends on both the T and D of the simulated data for each method. We choose the most accurate method among those we test for capturing any shape of response surface from real data, NPMR. Finally, we use NPMR to build response surfaces and quantify T and D from real ecological data sets. We demonstrate how measuring threshold strength and diagonality from multi-factor response surfaces can advance ecology.  相似文献   
275.
Using the concept of ontological security, this paper examines the physical and psychological loss of home and community following Hurricane Katrina. This qualitative longitudinal study includes 40 heads of households with school‐age children who lived in New Orleans during Hurricane Katrina. Participants describe a breakdown in their social fabric at the individual and structural/community levels that contributes to a sense of community loss and social displacement, disrupting their ontological security—their notion of safety, routine and trust in a stable environment. Three interrelated reactions were common: 1) experiencing nostalgia for their old neighbourhoods specifically and New Orleans in general; 2) experiencing a sense of loss of people and things that represented a level of security or constancy; 3) initiation of a process for re‐establishing ontological security whether or not they returned to New Orleans. The paper concludes that intangible losses have an important psychological effect on community redevelopment and recovery from trauma.  相似文献   
276.

Problem

Falling is a leading cause of serious injury, loss of independence, and nursing-home admission in older adults. Impaired balance control is a major contributing factor.

Methods

Results from our balance-control studies have been applied in the development of new and improved interventions and assessment tools. Initiatives to facilitate knowledge-translation of this work include setting up a new network of balance clinics, a research-user network and a research-user advisory board.

Results

Our findings support the efficacy of the developed balance-training methods, balance-enhancing footwear, neuro-prosthesis, walker design, handrail-cueing system, and handrail-design recommendations in improving specific aspects of balance control.

Impact on Knowledge Users

A new balance-assessment tool has been implemented in the first new balance clinic, a new balance-enhancing insole is available through pharmacies and other commercial outlets, and handrail design recommendations have been incorporated into 10 Canadian and American building codes. Work in progress is expected to have further impact.  相似文献   
277.
Refuge chambers are new devices for underground coal mines that provide approximately 96 h of breathable air, water, food, and supplies in the event of an emergency where miners are unable to escape. Researchers at the National Institute for Occupational Safety and Health (NIOSH) developed a training program to prepare miners for what to expect psychologically and physiologically inside of a refuge chamber. The field tests of this training revealed that it was received very positively by miners and helped impart realistic views about the physical discomforts and psychological stresses of being inside a refuge chamber.  相似文献   
278.

Objective

To evaluate CarFit, an educational program designed to promote optimal alignment of driver with vehicle.

Methods

A driving activity survey was sent to 727 randomly selected participants living in retirement communities. Drivers (n = 195) were assigned randomly to CarFit intervention (n = 83, M age = 78.1) or Comparison (n = 112, M age = 79.6) groups. After 6 months, participants completed a post-test of driving activity and CarFit recommendations.

Results

Nonconsenting drivers were older and participated in fewer driving activities. CarFit participation was moderate (71%) with 86% of the participants receiving recommendations. 60% followed the recommendations at the 6-month re-evaluation). The CarFit (67.6%) and Comparison (59.3%) groups reported at least one type of self-regulation of driving activity at baseline. There was no significant change in the driving behaviors at the six-month follow-up.

Conclusion

CarFit was able to detect addressable opportunities that may contribute to the safety of older drivers.

Impact on industry

CarFit recommendations may need stronger reinforcement in order to be enacted by a participant.  相似文献   
279.
Overexploitation is the second biggest driver of global plant extinction. Meanwhile, useful plant species are vital to livelihoods across the world, with global conservation efforts increasingly applying the concept of ‘conservation-through-use.’ However, successfully balancing conservation and biodiversity use remains challenging. We reviewed literature on the sustainability of wild-collected plant use across the countries of Colombia, Ecuador, Peru, and Bolivia—a region of global importance for its biological and cultural richness. After applying defined search terms and a two-stage screening process, 68 articles were reviewed. The numbers which reported sustainable, unsustainable, or context-dependent outcomes were relatively even, but national differences emerged. Through narrative synthesis, we identified five key, reoccurring themes: plant biology; land tenure; knowledge, resource, and capacity; economics and market pressures; and institutional structures, policy, and legislation. Our results show the need for flexible, context-specific approaches and the importance of collaboration, with bottom-up management and conservation methods involving local communities and traditional ecological knowledge often proving most effective. Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01529-7.  相似文献   
280.
Tentacles of the sea anemone, Nematostella vectensis, are covered with hair bundles. Hair bundles were deflected by water jets to test whether they are mechanoreceptors. Electrophysiological recordings confirm that deflections of hair bundles induce transients in membrane current. In a different species of anemone, hair bundle mechanoreceptors are known to change shape and responsiveness according to the activity of chemoreceptors that bind prey-derived compounds including N-acetylated sugars. In Nematostella, hair bundles significantly elongate upon exposure to NANA, an N-acetylated sugar. Based on a bioassay in which discharged nematocysts are counted in gelatin-coated test probes touched to tentacles, we find that NANA shifts vibration dependent discharge of basitrich nematocysts to lower frequencies overlapping those produced during swimming by known prey including planktonic crustaceans. Furthermore, we find for the first time that vibration detection extends at least 2.5 cm beyond the tentacle tips. Thus, Nematostella likely employs its hair bundles to detect swimming movements of nearby prey.  相似文献   
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