نتایج جستجو برای: habitat loss

تعداد نتایج: 495126  

Journal: :American journal of primatology 2014
Víctor Arroyo-Rodríguez Lenore Fahrig

With accelerated deforestation and fragmentation through the tropics, assessing the impact that landscape spatial changes may have on biodiversity is paramount, as this information is required to design and implement effective management and conservation plans. Primates are expected to be particularly dependent on the landscape context; yet, our understanding on this topic is limited as the maj...

2005
Ricard V. Solé Frederic Bartumeus Javier G. P. Gamarra J. G. P. Gamarra

Rainforests biodiversity is sustained by the three-dimensional structure of their canopy which provides a wide range of physical microenvironments. Given the dynamic nature of the forest, the recognition of stable vertical layers or strata in the canopy is controversial. The spatial characterisation of potential habitats of understory species is not straightforward due to the complex structure ...

2003
John E. Hasse Richard G. Lathrop

Sprawl has been loosely defined as dispersed and inefficient urban growth. We propose a series of five indicators that examine the per capita consumption of land taken in new development in relation to several critical land resource impacts associated to sprawl including: (1) density of new urbanization; (2) loss of prime farmland; (3) loss of natural wetlands; (4) loss of core forest habitat; ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - دانشکده فنی و مهندسی 1391

در این پروژه فیلترهای مایکرواستریپ جدیدی برای به‎‎دست آوردن اندازه‎ی فشرده، پاسخ تیز و نیز باند قطع عریض ارائه‎ شده است که از جمله‎ی آن ها فیلتری است که از سری شدن یک رزوناتور شاخه‎ای منتهی به نیم‎دایره و یک تکه‎ی‎ شعاعی بهبود یافته به عنوان تضعیف کننده‎ی هارمونیک، تشکیل شده است. فرکانس قطع -3 db این فیلتر در 1.54 ghz قرار دارد. باند‎ گذر این فیلتر تنها 0.26 ghz است که شامل محدوده‎ی فرکانسی 1.5...

2010
Xingli Giam Corey J.A. Bradshaw Hugh T.W. Tan Navjot S. Sodhi

Rapid land-use and climate changes are projected to cause broad-scale global land-cover transformation that will increase species extinction rates. We assessed the exposure of globally threatened plant biodiversity to future habitat loss over the first half of this century by testing country-level associations between threatened plant species richness and future habitat loss owing to land-use a...

2006
KRISTA L. RYALL LENORE FAHRIG

Despite extensive empirical research and previous reviews, no clear patterns regarding the effects of habitat loss and fragmentation on predator–prey interactions have emerged. We suggest that this is because empirical researchers do not design their studies to test specific hypotheses arising from the theoretical literature. In fact, theoretical work is almost completely ignored by empirical r...

Journal: :Ecology 2009
Rachael Winfree Ramiro Aguilar Diego P Vázquez Gretchen LeBuhn Marcelo A Aizen

Pollinators may be declining globally, a matter of concern because animal pollination is required by most of the world's plant species, including many crop plants. Human land use and the loss of native habitats is thought to be an important driver of decline for wild, native pollinators, yet the findings of published studies on this topic have never been quantitatively synthesized. Here we use ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید