نتایج جستجو برای: ecoregion

تعداد نتایج: 734  

Journal: :Journal of environmental sciences 2014
Fengyu Zan Shouliang Huo Jingtian Zhang Li Zhang Beidou Xi Lieyu Zhang

Arsenic (As) fractions in the sediments of seven lakes from East Plain Ecoregion and six lakes from Yungui Plateau Ecoregion, China, were investigated. Results indicated that the total As concentrations in sediment samples of lakes of the East Plain Lake Ecoregion are higher than those of Yungui Plateau Lake Ecoregion. Residual As is the main fraction in sediment samples of lakes from both ecor...

2011
THOMAS K. SABU

Species composition, distribution patterns and endemism are outlined for the dung beetles in the ecoregions of the western slopes of the moist South Western Ghats, South India. Among the 142 dung beetle species known, 35 are endemic to the Western Ghats; 29 are endemic to the moist South Western Ghats; 25 are regionally endemic to the South Western Ghats montane rain forests ecoregion; and one ...

Journal: :Journal of environmental quality 2003
Mostafa A Shirazi Colleen Burch Johnson James M Omernik Denis White Patricia K Haggerty Glenn E Griffith

Researchers have defined and mapped ecological regions of the United States based on similar patterns of ecosystems such as deserts, forests, and croplands. These studies are useful in regional research, monitoring, and environmental management because data can be more readily extrapolated within the same ecoregion and to regions with similar characteristics. The description of ecoregions is la...

Journal: :ISPRS Int. J. Geo-Information 2013
Kirk C. Silver Mark Carroll

Recent profound changes have been observed in the Arctic environment, including record low sea ice extents and high latitude greening. Studying the Arctic and how it is changing is an important element of climate change science. The Tundra, an ecoregion of the Arctic, is directly related to climate change due to its effects on the snow ice feedback mechanism and greenhouse gas cycling. Like all...

Journal: :Environmental management 2004
William W Hargrove Forrest M Hoffman

Multivariate clustering based on fine spatial resolution maps of elevation, temperature, precipitation, soil characteristics, and solar inputs has been used at several specified levels of division to produce a spectrum of quantitative ecoregion maps for the conterminous United States. The coarse ecoregion divisions accurately capture intuitively-understood regional environmental differences, wh...

Journal: :Environmental management 2004
Robert S Thompson Sarah L Shafer Katherine H Anderson Laura E Strickland Richard T Pelltier Patrick J Bartlein Michael W Kerwin

Ecoregion classification systems are increasingly used for policy and management decisions, particularly among conservation and natural resource managers. A number of ecoregion classification systems are currently available, with each system defining ecoregions using different classification methods and different types of data. As a result, each classification system describes a unique set of e...

2013
Li Xiaowen Zhuge Haijin Mengdi Li

The Central Yangtze Ecoregion contains a large area of internationally important freshwater wetlands and supports a huge number of endangered waterbirds; however, these unique wetlands and the biodiversity they support are under the constant threats of human development pressures, and the prevailing conservation strategies generated based on the local scale cannot adequately be used as guidelin...

Journal: :Ecology 2014
Luis Mauricio Bini Victor Lemes Landeiro André Andrian Padial Tadeu Siqueira Jani Heino

Beta diversity, the spatial or temporal variability of species composition, is a key concept in community ecology. However, our ability to predict the relative importance of the main drivers of beta diversity (e.g., environmental heterogeneity, dispersal limitation, and environmental productivity) remains limited. Using a comprehensive data set on stream invertebrate assemblages across the cont...

2012
Meredith C. Payne Cheryl A. Brown Deborah A. Reusser Henry Lee

The quantification and description of sea surface temperature (SST) is critically important because it can influence the distribution, migration, and invasion of marine species; furthermore, SSTs are expected to be affected by climate change. To better understand present temperature regimes, we assembled a 29-year nearshore time series of mean monthly SSTs along the North Pacific coastline usin...

Journal: :PLoS ONE 2007
Yoshan Moodley Michael W. Bruford

BACKGROUND Biogeographic models partition ecologically similar species assemblages into discrete ecoregions. However, the history, relationship and interactions between these regions and their assemblages have rarely been explored. METHODOLOGY/PRINCIPAL FINDINGS Here we develop a taxon-based approach that explicitly utilises molecular information to compare ecoregion history and status, which...

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