نتایج جستجو برای: habitat degradation

تعداد نتایج: 203316  

2017
David M. Schulte

Oyster populations in Virginia’s waters of Chesapeake Bay were lightly exploited until the early 1800s, when industrial fishery vessels first arrived, driven south from New England due to the collapse of northeastern oyster fisheries. Early signs of overexploitation and habitat degradation were evident by the 1850s. The public fishery, where oyster fishers harvest on state-owned bottom, rapidly...

2004
CARLOS CARROLL NATHAN H. SCHUMAKER

To conserve biological diversity, protected-area networks must be based not only on current species distributions but also on the landscape’s long-term capacity to support populations. We used spatially explicit population models requiring detailed habitat and demographic data to evaluate the ability of existing park systems in the Rocky Mountain region (U.S.A. and Canada) to sustain population...

Journal: :Trends in ecology & evolution 2008
Barry W Brook Navjot S Sodhi Corey J A Bradshaw

If habitat destruction or overexploitation of populations is severe, species loss can occur directly and abruptly. Yet the final descent to extinction is often driven by synergistic processes (amplifying feedbacks) that can be disconnected from the original cause of decline. We review recent observational, experimental and meta-analytic work which together show that owing to interacting and sel...

2012
Anuj Tyagi D. C. Sangwan Praveen Kumar Sharma R. Sirohi I. Y. Choi J. J. Ko

An extensive in vitro study was conducted to delineate the influence of levels and source of sulfur besides rumen fungi habitat on the degradation of pearl millet stover dry matter and fibrous constituents. The results revealed that degradability of dry matter, organic matter, acid detergent fibre, neutral detergent fibre and cellulose from pearl millet stover was maximized (P<0.05), irrespecti...

Journal: :Current biology : CB 2017
Hui Yu Xin Wang Lei Cao Lu Zhang Qiang Jia Hansoo Lee Zhenggang Xu Guanhua Liu Wenbin Xu Binhua Hu Anthony D Fox

While wild goose populations wintering in North America and Europe are mostly flourishing by exploiting farmland, those in China (which seem confined to natural wetlands) are generally declining. Telemetry devices were attached to 67 wintering wild geese of five different species at three important wetlands in the Yangtze River Floodplain (YRF), China to determine habitat use. 50 individuals of...

Journal: :Nature communications 2013
Rebecca Biton Eli Geffen Miguel Vences Orly Cohen Salvador Bailon Rivka Rabinovich Yoram Malka Talya Oron Renaud Boistel Vlad Brumfeld Sarig Gafny

Amphibian declines are seen as an indicator of the onset of a sixth mass extinction of life on earth. Because of a combination of factors such as habitat destruction, emerging pathogens and pollutants, over 156 amphibian species have not been seen for several decades, and 34 of these were listed as extinct by 2004. Here we report the rediscovery of the Hula painted frog, the first amphibian to ...

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