نتایج جستجو برای: habitat characteristics
تعداد نتایج: 709822 فیلتر نتایج به سال:
Scientists have long assumed that the physical structure and condition of stream and river channels have pervasive effects on biological communities and processes, but specific tests are few. To investigate the influence of the stream-reach geomorphic state on in-stream habitat and aquatic macroinvertebrate communities, we compared measures of habitat conditions and macroinvertebrate community ...
Understanding how animals utilize available space is important for their conservation, as it provides insight into the ecological needs of the species, including those related to habitat, prey and inter and intraspecific interactions. We used 28 months of radio telemetry data and information from 200 kill locations to assess habitat selection at the 3rd order (selection of habitats within home ...
Patterns of habitat use by fish assemblages in two chalk streams in southern England were examined to identify species preferences with respect to major habitat gradients. Both study sites, although differing in some physical habitat characteristics, mainly channel width, water temperature and instream cover, could be arranged similarly along a continuum extending from erosional to depositional...
Tityus gonzalespongai n. sp. is a species endemic to the high mountains of Anzoátegui State, Venezuela. It is found between 1,600 and 2,200 m in “La Laguna” mountain. Its habitat includes the area of “Bosque Húmedo Montano Bajo” with the type of vegetation of “Bosque Ombrófilo Montano Siempreverde” (“Bosques Nublados Costeros” that includes the “Subpáramos Arbustivos”). It is distinguished from...
objective: ageing of the stored seed is a natural phenomenon and the seeds tend to lose viability even under ideal storage conditions. accelerated ageing has been recognized as a good predictor of the storability of seed lots. aged seeds show decreased vigor and produce weak seedlings that are unable to survive once reintroduced into a habitat. the characteristics of the chemical composition of...
Large portions of anadromous salmonid habitat in the western United States has been lost because of dams and other blockages. This loss has the potential to affect salmonid evolution through natural selection if the loss is biased, affecting certain types of habitat differentially, and if phenotypic traits correlated with those habitat types are heritable. Habitat loss can also affect salmonid ...
We introduce the term metacity as a conceptual framework that can be shared by ecologists and designers and applied across the wide variety of urban habitats found around the world. While the term metacity was introduced by UN-HABITAT to designate hyper cities of over twenty million people, for us it is not limited to large urban agglomerations, but rather refers to the proliferation of new for...
Reflecting the lack of critical information for most protected species, recovery plans for organisms listed as threatened or endangered under the U.S. Endangered Species Act tend to oversimplify habitat descriptions. Here we present our approach for improving the definition of habitat for rare and patchily distributed listed species. The valley elderberry longhorn beetle (Desmocerus californicu...
Understanding patterns of habitat selection across a species’ geographic distribution can be critical for adequately managing populations and planning for habitat loss and related threats. However, studies of habitat selection can be time consuming and expensive over broad spatial scales, and a lack of standardized monitoring targets or methods can impede the generalization of site-based studie...
Several studies have shown that large wood has a prominent role in habitat quality, however there is little research on the role of wood on pool characteristics and other habitat components in low gradient streams (channel slopes less than one percent). Longitudinal profiles are used to analyze general residual pool characteristics of three approximately 1000meter stream reaches with similar st...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید