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Amy B. Mui Brennan Caverhill Bob Johnson Marie-Josée Fortin Yuhong He 《Landscape Ecology》2017,32(3):531-546
Context
Landscapes and animal behavior can exhibit temporal variability and connectivity estimates should consider this phenomenon. In many species, timing of activities such as nesting, mate searching, and hibernation occurs during distinct periods in which movement events may differ, along with physical characteristics of the surrounding landscape.Objectives
We estimate movement, landscape conductance, and patch importance for a turtle species across two seasonal activity periods (spring, late summer) in a fragmented agricultural region. Three connectivity approaches are compared to identify their advantages and disadvantages.Methods
A least-cost distance model, circuit-based approach, and patch-based index were used to collectively describe the potential functional connectivity of Blanding’s turtle (Emydoidea blandingii) across a multi-temporal scale in an agricultural region of south western Ontario.Results
Connectivity decreased further into the active season exhibited through lower conductance of the landscape and fewer pathways, while the importance of habitat nodes shifted due to temporal variability in the number and distribution of nodes. Models provided different yet complimentary information, with least-cost models overestimating discrete pathways yet providing a secondary measure of landscape barriers. The circuit-based model estimated corridors of least resistance providing an overall characterization of the landscape, while patch-based indices provided key information on the importance of individual habitat patches.Conclusion
Findings highlight the importance of including a temporal aspect in connectivity modelling as results demonstrate a change in functional connectivity over time. We also recommend employing multiple connectivity metrics to capture variation in movement behavior.33.
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保育仔猪饲养管理比日粮配方更加重要 总被引:3,自引:0,他引:3
对早期断奶仔猪而言,一套成功的饲养管理制度必须要克服几方面的问题,而其中的许多问题是相互关联的。因此,一旦这些问题中的某一个出现了显著的不足,虽然仍能制订出可以接受的饲养管理方案,但将使仔猪的生产性能低于期望值。我们研究了许多种生产方式,并与各种各样的人打交道, 相似文献
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1. The effects of relatively small concentrations of polychlorinated biphenyls (PCB) in the diet of hens on the hepatic microsomal aryl 4-monooxygenase [EC 1.14.14.1] activity in their progeny were investigated. 2. PCB caused enhanced activity of aryl 4-monooxygenase in the progeny. 相似文献
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