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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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Paired-site approach for studying soil organic carbon dynamics in a Mediterranean semiarid environment

Journal Articles & Books
Décembre, 2012

This work investigated the effects of land cover and land-use change (LUC) on the ability of a soil to store carbon (C) and reduce carbon dioxide (CO₂) emissions, in a Mediterranean area. Using a paired-site approach, we estimated the effect of land-cover change on the C stock from 1972 to 2008 in a natural reserve (Grotta di Santa Ninfa) in western Sicily. We selected 15 paired sites representative of five LUCs.

Modelling vascular plant diversity at the landscape scale using systematic samples

Journal Articles & Books
Décembre, 2008
Suisse
Europe

We predict fine-scale species richness patterns at large spatial extents by linking a systematic sample of vascular plants with a multitude of independent environmental descriptors. Switzerland, covering 41,244 km² in central Europe. Vascular plant species data were collected along transects of 2500-m length within 1-km² quadrats on a systematic national grid (n = 354), using a standardized assessment method. Generalized linear models (GLM) were used to correlate species richness of vascular plants per transect (SRt) with three sets of variables: topography, environment and land cover.

Assessment of Beetle and Bug Diversity in Extensively Managed Cattle Farms of Varying Cattle Density, Sward Height, and Surrounding Land Use

Journal Articles & Books
Décembre, 2015

Livestock that is extensively managed can have higher diversity and abundance of insects in comparison to intensively managed livestock, although data are more equivocal within a gradient of extensively managed pastures. Additionally, biodiversity on farms is vulnerable to degradation of the surrounding landscape and changing patterns of land use. We monitored Coleoptera and Hemiptera on grass-fed cattle farms in North Carolina to determine effects of cattle and land use patterns on biodiversity.

Cashew Orchards Conserve the Potential for Forest Recovery

Journal Articles & Books
Décembre, 2015

Outside of agroforestry disciplines, “orchards” and “forests” are usually studied through different fields of knowledge or are mired in conflicting views. Our study aimed to provide preliminary information on regeneration in cashew orchards by studying the effect of previous land cover, the surrounding landscape, and orchards’ age on the density of species and number of plants. We followed linear transects in orchards planted in areas previously covered by savannah and forest.

Co-kriging for modeling shallow groundwater level changes in consideration of land use/land cover pattern

Journal Articles & Books
Décembre, 2013
Japon

This study aimed at clarifying the relationship between the dynamics of land use/land cover (LULC) changes and decline in the groundwater levels, and specifying an LULC category strongly affecting such decline in a Quaternary sedimentary basin. Groundwater level data recorded at 26 observation wells for a 14-year period in the Kumamoto Plain, central Kyushu, southwest Japan, were used for the analysis. The general trends of LULC were detected by a satellite image classification technique and surface spline method, which highlighted the decreases in groundwater-recharge materials.

Controls of dissolved organic matter quality: evidence from a large‐scale boreal lake survey

Journal Articles & Books
Décembre, 2014
Suède

Inland waters transport large amounts of dissolved organic matter (DOM) from terrestrial environments to the oceans, but DOM also reacts en route, with substantial water column losses by mineralization and sedimentation. For DOM transformations along the aquatic continuum, lakes play an important role as they retain waters in the landscape allowing for more time to alter DOM. We know DOM losses are significant at the global scale, yet little is known about how the reactivity of DOM varies across landscapes and climates. DOM reactivity is inherently linked to its chemical composition.

Establishing turf grass increases soil greenhouse gas emissions in peri-urban environments

Journal Articles & Books
Décembre, 2016
Global

Urbanization is becoming increasingly important in terms of climate change and ecosystem functionality worldwide. We are only beginning to understand how the processes of urbanization influence ecosystem dynamics and how peri-urban environments contribute to climate change. Brisbane in South East Queensland (SEQ) currently has the most extensive urban sprawl of all Australian cities. This leads to substantial land use changes in urban and peri-urban environments and the subsequent gaseous emissions from soils are to date neglected for IPCC climate change estimations.

Using information on ecosystem services in Nepal to inform biodiversity conservation and local to national decision-making

Journal Articles & Books
Décembre, 2016
Népal

Policy-makers are paying increasing attention to ecosystem services, given improved understanding that they underpin human well-being, and following their integration within the Aichi Targets of the Convention on Biological Diversity. Decision-makers need information on trends in biodiversity and ecosystem services but tools for assessing the latter are often expensive, technically demanding and ignore the local context.

Impact of Topography on Accuracy of Land Cover Spectral Change Vector Analysis Using AWiFS in Western Himalaya

Journal Articles & Books
Décembre, 2013

The present paper discusses the impact of topography on accuracy for land cover classification and “from-to class change using improved spectral change vector analysis suggested by Chen et al. (2003). Two AWiFS sensor images of different dates are used. Double Window Flexible Pace Search (DFPS) is used to estimate threshold of change magnitude for change/no change classes. The topographic corrections show accuracy of 90% (Kappa coefficient 0.7811) for change/no change area as compared to 82% (Kappa coefficient 0.6512) in uncorrected satellite data.

Using MERIS fused images for land-cover mapping and vegetation status assessment in heterogeneous landscapes

Journal Articles & Books
Décembre, 2011
Pays-Bas

In this paper we evaluate the potential of ENVISAT–Medium Resolution Imaging Spectrometer (MERIS) fused images for land-cover mapping and vegetation status assessment in heterogeneous landscapes. A series of MERIS fused images (15 spectral bands; 25 m pixel size) is created using the linear mixing model and a Landsat Thematic Mapper (TM) image acquired over the Netherlands. First, the fused images are classified to produce a map of the eight main land-cover types of the Netherlands. Subsequently, the maps are validated using the Dutch land-cover/land-use database as a reference.

Vegetation change in Brazil’s dryland ecoregions and the relationship to crop production and environmental factors: Cerrado, Caatinga, and Mato Grosso, 2001–2009

Journal Articles & Books
Décembre, 2013
Brésil

South America’s drylands remain some of the most threatened ecosystems on the planet. Yet, we know very little about the dynamics of land-use and land-cover change (LUCC) in these understudied regions. Our objective is to map vegetation change in Brazil’s three largest dryland ecoregions – the Cerrado, Caatinga, and Mato Grosso seasonal forests – using MODIS (Moderate Resolution Imaging Spectroradiometer) data from 2001 to 2009 at the scale of the municipality.

Characterizing changes in urban landscape of Nairobi city, Kenya

Journal Articles & Books
Décembre, 2011
Kenya

Landscapes in urban areas especially in developing countries are under pressure due to increasing population of urban dwellers and un-directed spread of city boundaries. Sound urban environment plays important aesthetic, ecological, cultural, social and engineering roles beneficial to the people. To support better management of vegetated sites, it is necessary to understand the spatial configuration at the landscape scale and changes that have occurred.