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Issuescouverture du solLandLibrary Resource
There are 2, 240 content items of different types and languages related to couverture du sol on the Land Portal.

couverture du sol

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Upper Washita River Experimental Watersheds: Reservoir, Groundwater, and Stream Flow Data

Journal Articles & Books
Décembre, 2014

Surface and groundwater quantity and quality data are essential in many hydrologic applications and to the development of hydrologic and water quality simulation models. We describe the hydrologic data available in the Little Washita River Experimental Watershed (LWREW) of the Southern Great Plains Research Watershed (SGPRW) and Fort Cobb Reservoir Experimental Watershed (FCREW), both located in southwest Oklahoma.

Spatial and Temporal Variability of Soil Organic Carbon in the Corn Belt of Northeastern China, 1980s–2005: A Case Study in Four Counties

Journal Articles & Books
Décembre, 2014
Chine

Estimates of changes and possible causes of regional soil organic carbon (SOC) are critical for evaluation of potential responses of terrestrial biosphere to global changes. A total of 382 soil samples, collected in the 1980s from four counties in the Corn Belt of northeastern China, and of 1,514 samples collected in 2005 from the same area, were examined for SOC concentrations. Spatial and temporal SOC concentrations were evaluated after the 25-year interval using geostatistics and kriging interpolation method.

Land Ownership and Land‐Cover Change in the Southern Appalachian Highlands and the Olympic Peninsula

Journal Articles & Books
Décembre, 1996

Social and economic considerations are among the most important drivers of landscape change, yet few studies have addressed economic and environmental influences on landscape structure, and how land ownership may affect landscape dynamics. Watersheds in the Olympic Peninsula, Washington, and the southern Appalachian highlands of western North Carolina were studied to address two questions: (1) Does landscape pattern vary among federal, state, and private lands?

model to predict stream water temperature across the conterminous USA

Journal Articles & Books
Décembre, 2015
États-Unis d'Amérique

Stream water temperature (tₛ) is a critical water quality parameter for aquatic ecosystems. However, tₛrecords are sparse or nonexistent in many river systems. In this work, we present an empirical model to predict tₛat the site scale across the USA. The model, derived using data from 171 reference sites selected from the Geospatial Attributes of Gages for Evaluating Streamflow database, describes the linear relationship between monthly mean air temperature (tₐ) and tₛ.

Posterior probability-based optimization of texture window size for image classification

Journal Articles & Books
Décembre, 2014

Texture provides spatial features complementary to spectral information in land cover classification of high spatial resolution imagery. In texture classification, window size is an important factor influencing classification accuracy, but selecting the optimal window size is difficult. In this paper, we propose an optimized window size texture classification method which can solve the window size selection problem.

Identifying Major Factors Controlling Groundwater Quality in Semiarid Area Using Advanced Statistical Techniques

Journal Articles & Books
Décembre, 2014

There are many factors controlling groundwater pollution and vulnerability. However, the factors’ weights are still not reasonably investigated. In order to assess groundwater quality and the controlling factors in semiarid region, 178 groundwater samples were collected and analyzed for salinity and nitrate content. New statistical techniques of prediction profiler and hierarchical cluster combined with geographic information systems (GIS) were used to assess the groundwater quality based on three categorical controlling factors; landuse/ land cover (LULC), soil texture, and aquifer type.

Geospatial and geostatistical approach for groundwater potential zone delineation

Journal Articles & Books
Décembre, 2015
Inde

Over the past few decades, groundwater has become an essential commodity owing to increased demand as a result of growing population, industrialization, urbanization and so on. The water supply situation is expected to become more severe in the future because of continued unsustainable water use and projected change in hydrometeorological parameters due to climate change.

Angular effect of MODIS emissivity products and its application to the split-window algorithm

Journal Articles & Books
Décembre, 2011
Asie orientale

The angular effects of emissivity are ignored in current land surface temperature (LST) products. As a result, the directionality of these LST products limits their further application in many fields. Accurate correction of the angular problem of LST products requires explicit understanding of the angular effects of emissivity at the pixel scale. Currently, nearly ten years of global emissivity products of MODIS are available. However, the pixel-scale directionality of emissivity has never been analyzed.

Nitrogen isotope tracer acquisition in low and tall birch tundra plant communities: a 2� year test of the snow–shrub hypothesis

Journal Articles & Books
Décembre, 2014

Deciduous shrub density and landcover are increasing across many areas of the Arctic. Shrub growth may be promoted by a snow–shrub feedback whereby relatively tall shrubs accumulate deeper snow, raising winter soil temperature minima, increasing microbial activity, and enhancing soil solution nitrogen (N). Although there is good evidence for the above components of the hypothesis, it has not yet been determined if shrubs can access the elevated N pool generated by deepened snow.

Land subsidence and declining water resources in Quetta Valley, Pakistan

Journal Articles & Books
Décembre, 2013
Pakistan
Afghanistan

Extensive groundwater withdrawals in urban areas may cause water shortages, land subsidence, and water quality problems. The Quetta Valley is the largest population center in Balochistan province in western Pakistan. This area is arid and groundwater is the main water source for domestic and agricultural use. This work presents global positioning system (GPS) data and assessment of spatial and temporal variations in water levels. GPS data from two stations from mid-2006 to the beginning of 2009 show subsidence rate of 10� cm\year.

Can remote sensing estimate fine-scale quality indicators of natural habitats?

Journal Articles & Books
Décembre, 2012

Efficient management and conservation of natural habitats requires a thorough knowledge and sustained monitoring of their ecological quality. In recent years, several methods have been developed to assess the local conservation status in the field. These typically combine estimates of coarse-scale indicators, such as tree and grass encroachments, with very fine-scale indicators that require precise fieldwork, such as the number of key species present. We first tested whether coarse-scale field characteristics can provide information on fine-scale indicators.

Corine land cover changes during the period 1990–2000 in the most important areas for birds in Croatia

Journal Articles & Books
Décembre, 2011
Croatie

The authors researched changes in specific habitat types in areas considered to be the most important in Croatia for protection of endangered bird fauna during the period 1990–2000. The analysis focused on four areas in the continental part of Croatia (Danube and Drava River alluvium, Pokupsko depression, Sava River basin, Upper Drava River basin) and four areas in the Mediterranean part (Neretva River estuary, NW part of North Dalmatia, Paško field, Lake Vrana). For the classified habitat types, changes in Corine land cover databases in 1990 and 2000 were analysed.