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Migrating Birds' use of Stopover Habitat in The Southwestern United States

Journal Articles & Books
Dezembro, 2012

In the arid Southwest, migratory birds are known to use riparian stopover habitats; we know less about how migrants use other habitat types during migratory stopover. Using radar data and satellite land-cover data, we determined the habitats with which birds are associated during migration stopover. Bird densities differed significantly by habitat type at all sites in at least one season. In parts of Arizona and New Mexico upland forest supported high densities of migrants, especially in fall. Developed habitat, in areas with little upland forest, also supported high densities of migrants.

Larval ecology of mosquitoes in sylvatic arbovirus foci in southeastern Senegal

Journal Articles & Books
Dezembro, 2012
Senegal

BACKGROUND: Although adult mosquito vectors of sylvatic arbovirus [yellow fever (YFV), dengue-2 (DENV-2) and chikungunya (CHIKV)] have been studied for the past 40 years in southeastern Senegal, data are still lacking on the ecology of larval mosquitoes in this area. In this study, we investigated the larval habitats of mosquitoes and characterized their seasonal and spatial dynamics in arbovirus foci. METHODS: We searched for wet microhabitats, classified in 9 categories, in five land cover classes (agriculture, forest, savannah, barren and village) from June, 2010 to January, 2011.

Effects of Land Cover Disturbance on Stream Invertebrate Diversity and Metal Concentrations in a Small Urban Industrial Watershed

Journal Articles & Books
Dezembro, 2012

The landscape surrounding Sudbury, Ontario, has been severely affected by 100 years of mining and forestry and a recent, large-scale ecological risk assessment found that terrestrial plant communities continue to be impaired by remnant metals and poor soil conditions. We investigated the risks of these adverse landscape conditions on a small headwater stream by digitizing land cover at a fine scale and relating it to benthic invertebrate diversity and metal concentrations at 13 sites in the system.

Near surface air humidity in a megadiverse Andean mountain ecosystem of southern Ecuador and its regionalization

Journal Articles & Books
Dezembro, 2012
Equador

The near surface humidity in a megadiverse mountain ecosystem in southern Ecuador is examined on the basis of Relative Humidity (RH) measurements inside the natural mountain forest and at open sites along an altitudinal gradient from 1700 to 3200m. The main methodological aim of the current study is to generate a humidity regionalization tool to provide spatial datasets on average monthly mean, minimum and maximum RH, Specific Humidity (q) and Specific Saturation Deficit (DS) by using observation data of RH.

efficiency of sampling very high resolution images for area estimation in the European Union

Journal Articles & Books
Dezembro, 2012

Very high resolution (VHR) images are a valuable information source to estimate land cover area and land cover change. When full coverage of a region with VHR images is not affordable, a sample of images can be considered. Square grids provide a practical sampling frame for VHR images. When using a land cover map as pseudo-truth, the sampling variance is easily assessed but may be overestimated if the land cover map has a coarse resolution.

Mapping land-use and land-cover change along Bolivia's Corredor Bioceánico with CBERS and the Landsat series: 1975–2008

Journal Articles & Books
Dezembro, 2012
Bolívia
América Central
América do Sul

This study uses a combination of Landsat series data (Multispectral Scanner or MSS, Thematic Mapper or TM and Enhanced Thematic Mapper or ETM+) to map land-use and land-cover change (LULCC) from 1975 to 2001. It extends the land change record to 2008 using Chinese–Brazil Earth Resources Satellite (CBERS)-2 and CBERS-2B data on a multi-scene level. It also establishes a methodology to correct for systematic distortion inherent in CBERS imagery without the loss of information present in Landsat 7 ETM+ imagery post-2003.

Thermal anomalies associated with faults: a case study of the Jinhua–Quzhou basin of Zhejiang Province, China

Journal Articles & Books
Dezembro, 2012
China

Faults provide the path for geothermal natural convection and partially influence the ground surface thermal environment. The land surface temperatures (LSTs) near a fault are higher than in other areas and can indicate the strike trend of an underground fault. However, these anomalies of higher LSTs are not located accurately in the fault centre but near it with some offset, and these LST data may include other thermal information that needs to be eliminated prior to analysis.

Influence of a Large-scale Removal of an Invasive Plant (Melaleuca quinquenervia) on Home-range Size and Habitat Selection by Female Florida Panthers (Puma concolor coryi) within Big Cypress National Preserve, Florida

Journal Articles & Books
Dezembro, 2012

The control of invasive exotic plants is often deemed important for managing native wildlife, but surprisingly little research exists that evaluates benefits to wildlife, including species of conservation concern. Melaleuca quinquenervia (Melaleuca) is an invasive, non-native, broad-leaved tree that aggressively displaces native plant communities in south Florida.

Atmospheric mercury emissions in Australia from anthropogenic, natural and recycled sources

Journal Articles & Books
Dezembro, 2012
Austrália

The United Nations Environment Programme (UNEP) has begun a process of developing a legally binding instrument to manage emissions of mercury from anthropogenic sources. The UNEP Governing Council has concluded that there is sufficient evidence of significant global adverse impacts from mercury to warrant further international action; and that national, regional and global actions should be initiated as soon as possible to identify populations at risk and to reduce human generated releases.

Changes of crop rotation in Iowa determined from the United States Department of Agriculture, National Agricultural Statistics Service cropland data layer product

Journal Articles & Books
Dezembro, 2012
Estados Unidos

Crop rotation is one of the important decisions made independently by numerous farm managers, and is a critical variable in models of crop growth and soil carbon. In Iowa and much of the Midwestern United States (US), the typical management decision is to rotate corn and soybean crops for a single field; therefore, the land-cover changes each year even though the total area of agricultural land-use remains the same. The price for corn increased from 2001 to 2010, which increased corn production in Iowa.

Recent trends in solar exergy and net radiation at global scale

Journal Articles & Books
Dezembro, 2012

The availability during the last decades of remotely sensed images and global climatic data allow us to analyse the “Earth system” as a whole in order to develop concepts for global environmental management. This system can be considered a complex, dissipative, dynamic entity, far from thermodynamic equilibrium (Schellnhuber, 1999). Energy balance has been considered for many decades to understand the functioning of ecosystems, the biosphere or the Earth planet as a whole, but it is also possible to study our planet from a thermodynamic point of view.