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There are 2, 238 content items of different types and languages related to couverture du sol on the Land Portal.

couverture du sol

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How pervasive is biotic homogenization in human‐modified tropical forest landscapes?

Journal Articles & Books
Décembre, 2015

Land‐cover change and ecosystem degradation may lead to biotic homogenization, yet our understanding of this phenomenon over large spatial scales and different biotic groups remains weak. We used a multi‐taxa dataset from 335 sites and 36 heterogeneous landscapes in the Brazilian Amazon to examine the potential for landscape‐scale processes to modulate the cumulative effects of local disturbances.

Estimating net surface longwave radiation from net surface shortwave radiation for cloudy skies

Journal Articles & Books
Décembre, 2013

This work addresses the estimation of net surface longwave radiation (NSLR) from net surface shortwave radiation (NSSR) by analysing the Surface Radiation Budget Network (SURFRAD) radiation data under cloudy conditions. A general model is developed to estimate NSLR from the NSSR for cloudy skies with a root mean square error (RMSE) of 23.16 W m⁻² compared with in situ data. The model is applied to AmeriFlux data. The results show that the mean error and RMSE are –2.31 W m⁻² and 29.25 W m⁻², respectively, compared with the measurement of AmeriFlux.

Human impact on avian diversity in rural Mediterranean areas

Journal Articles & Books
Décembre, 2015

Human activities influence the biodiversity of Mediterranean ecosystems and are involved in the transformation of natural habitats into farmland. We surveyed birds using the point count method on 288 plots at a 50-m radius in three altitudinal landscapes with different rural character in spring and autumn. The results showed that bird species richness in the study area was high (74 species). High total species richness was found in the upland rural landscape characterized by mixed land use and high landscape diversity.

Sustainable agricultural residue removal for bioenergy: A spatially comprehensive US national assessment

Journal Articles & Books
Décembre, 2013
États-Unis d'Amérique

This study provides a spatially comprehensive assessment of sustainable agricultural residue removal potential across the United States for bioenergy production. Earlier assessments determining the quantity of agricultural residue that could be sustainably removed for bioenergy production at the regional and national scale faced a number of computational limitations. These limitations included the number of environmental factors, the number of land management scenarios, and the spatial fidelity and spatial extent of the assessment.

RGB-NDVI color composites for monitoring the change in mangrove area at the Maubesi Nature Reserve, Indonesia

Journal Articles & Books
Décembre, 2013
Indonésie

The Maubesi Nature Reserve (MNR) is a protected lowland area in eastern Indonesia that mainly consists of mangrove forest. The objective of this paper was to demonstrate a simple technique to visualize and quantify the change in mangrove area using a 3-year dataset of Landsat TM images acquired in 1989, 2003 and 2009. The normalized difference vegetation index (NDVI) was calculated to determine high and low vegetation biomass in each image.

Tidal Channel Diatom Assemblages Reflect within Wetland Environmental Conditions and Land Use at Multiple Scales

Journal Articles & Books
Décembre, 2015

We characterized regional patterns of the tidal channel benthic diatom community and examined the relative importance of local wetland and surrounding landscape level factors measured at multiple scales in structuring this assemblage. Surrounding land cover was characterized at the 100, 250, 1,000 m, and watershed buffer scales. Tidal channel benthic diatom communities were characterized by high species richness, abundance of rare species, and an abundance of species characterized as meso-eutraphentic and eutraphentic.

Benefits of earth observation data for conservation planning in the case of European wetland biodiversity

Journal Articles & Books
Décembre, 2013
Europe

To evaluate the status of biodiversity and to determine how current conservation efforts can be improved, biodiversity monitoring is crucial. An important aspect of data quality lies in its spatial resolution. It is unclear how finer scale land cover and land value information might further benefit biodiversity conservation. This paper aimed to assess the impacts of scale by modelling the conservation of endangered European wetland species and their corresponding habitats. Fine-scale datasets were derived by integrating existing geographical, biophysical and economic data.

Land-use change and its socio-environmental impact in Eastern Ethiopia’s highland

Journal Articles & Books
Décembre, 2014

The Alemaya district (Eastern Ethiopian highlands) is characterized by undulating physiographic features with arid, semi-arid, and humid climatic conditions. This study evaluated socio-environmental changes in land use and land cover during 1985–2011. Screen digitization on remotely sensed data (i.e., Landsat images from 1985 to 2011) was performed to produce 10 classes of land use and land cover. Then, final land-use maps were prepared using a geographic information system following field verification and accuracy assessment.

Assessing the relationship between the Lake Habitat Survey and littoral macroinvertebrate communities in European lakes

Journal Articles & Books
Décembre, 2013
Europe

Implementation of the EU Water Framework Directive (WFD) has drawn much attention to hydromorphological alterations of surface waters. The Lake Habitat Survey (LHS) protocol provides a method for characterising and assessing the physical habitats of lakes and reservoirs. Two metrics were developed based on this method: the Lake Habitat Modification Score (LHMS) and the Lake Habitat Quality Assessment (LHQA), as measures of lake modification and habitat value, respectively. However, the use of these metrics to predict measures of ecological quality remains largely untested.

Characteristics within and around stopover wetlands used by migratory shorebirds: Is the neighborhood important?

Journal Articles & Books
Décembre, 2015
Amérique septentrionale

Wetland stopover use by migratory shorebirds is concurrently influenced by habitat characteristics within a stopover site and characteristics related to the broader context surrounding the stopover site. To conserve wetland habitats essential for shorebird migration through the interior of North America, we need to understand how these dual scales influence stopover use.

Multiple SVM System for Classification of Hyperspectral Remote Sensing Data

Journal Articles & Books
Décembre, 2013

With recent technological advances in remote sensing sensors and systems, very high-dimensional hyperspectral data are available for a better discrimination among different complex land-cover classes. However, the large number of spectral bands, but limited availability of training samples creates the problem of Hughes phenomenon or ‘curse of dimensionality’ in hyperspectral data sets. Moreover, these high numbers of bands are usually highly correlated.

Finding Homogeneity in Heterogeneity--A New Approach to Quantifying Landscape Mosaics Developed for the Lao PDR

Journal Articles & Books
Décembre, 2009
Laos

A key challenge for land change science in general and research on swidden agriculture in particular, is linking land cover information to human-environment interactions over larger spatial areas. In Lao PDR, a country facing rapid and multi-level land change processes, this hinders informed policy- and decision-making. Crucial information on land use types and people involved is still lacking. This article proposes an alternative approach for the description of landscape mosaics.