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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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Towards long-multitemporal change detection using SVI differencing by integrated DWT–ISOCLUS: a model for forest temporal dynamics mapping

Journal Articles & Books
Décembre, 2011
Kenya

Characterisation and mapping of land cover/land use within forest areas over long-multitemporal intervals is a complex task. This complexity is mainly due to the location and extent of such areas and, as a consequence, to the lack of full continuous cloud-free coverage of those large regions by one single remote sensing instrument. In order to provide improved long-multitemporal forest change detection using Landsat MSS and ETM + in part of Mt.

Classification of Landsat images based on spectral and topographic variables for land-cover change detection in Zagros forests

Journal Articles & Books
Décembre, 2012

Detection of land-cover changes through time can be complicated because of sensor-specific differences in spatial and spectral resolutions; classified land-cover changes can be due to either real changes on the ground or a switch in sensors used to collect data.

Factors Influencing Occurrence of Passerines in the Reed Archipelago of Lake Velence (Hungary)

Journal Articles & Books
Décembre, 2006
Hongrie

Bird census data from the reed archipelago (109 islands) of Lake Velence, Hungary, were used to assess the relative importance of habitat scale variables (island area and shape, reed stand density and reed height) and landscape scale variables (distance to the nearest reed island and nearest large reed island, percentage of reed-, water- and land-cover around the islands). Habitat and landscape scale variables played a similar general role in explaining the presence of the eight observed reedbed passerines.

Vegetation‐environment relationships in Atlantic European calcareous grasslands

Journal Articles & Books
Décembre, 2000
France
Irlande
Espagne

The relationship between vegetation and environment was investigated for calcareous grasslands in a region in the west of Spain, France, Britain and Ireland defined by climatic criteria. Vegetation was sampled using objective methods and data collected on soils, land cover, location and management. Climate data were obtained from an available database. Examination of the first axis of vegetation variation as defined by Detrended Correspondence Analysis (DCA) showed a gradient from the Irish and British samples to those from France.

global land-cover validation data set, II: augmenting a stratified sampling design to estimate accuracy by region and land-cover class

Journal Articles & Books
Décembre, 2012

A global validation database that can be used to assess the accuracy of multiple global and regional land-cover maps would yield significant cost savings and enhance comparisons of accuracy of different maps. Because the global validation database should expand over time as new validation data are contributed, the sampling design must be constructed so that it is simple to increase the sample size from a specific region (e.g. a continent or country) or from targeted land-cover classes to improve standard errors of the accuracy estimates.

Performance of indicators and the effect of grain size in the discrimination of plant communities for restoration purposes

Journal Articles & Books
Décembre, 2008
Italie

There is strong pressure to embrace indicators for practical goals such as nature conservation and management and to evaluate the restoration success, but the selection of appropriate indicators is not straightforward. In addition, the grain and the type of data collected and data transformation adopted can influence restoration monitoring results. In this paper, we assessed the effect of changing indicator, grain size (i.e., plot dimension) and data transformation in discriminating different mapped plant communities, relying on vascular plant composition data.

Principles for life cycle inventories of land use on a global scale

Journal Articles & Books
Décembre, 2013

PURPOSE: To assess the diverse environmental impacts of land use, a standardization of quantifying land use elementary flows is needed in life cycle assessment (LCA). The purpose of this paper is to propose how to standardize the land use classification and how to regionalize land use elementary flows. MATERIALS AND METHODS: In life cycle inventories, land occupation and transformation are elementary flows providing relevant information on the type and location of land use for land use impact assessment.

Accessibility as a determinant of landscape transformation in western Honduras: linking pattern and process

Journal Articles & Books
Décembre, 2003
Honduras

This study evaluates the relationship between landscape accessibility and land cover change in Western Honduras, and demonstrates how these relationships are influenced by social and economic processes of land use change in the region. The study area presents a complex mosaic of land cover change processes that involve approximately equal amounts of reforestation and deforestation.

Land Cover Controls the Export of Terminal Electron Acceptors from Boreal Catchments

Journal Articles & Books
Décembre, 2015

NO₃, Mn, Fe, and SO₄act as terminal electron acceptors (TEAs), modifying mineralization pathways and coupling biogeochemical cycles. Although single TEA concentrations and fluxes have been intensively studied, the factors regulating the simultaneous fluxes and molar ratios of TEAs are poorly elucidated. We studied the mean concentrations, exports, and molar ratios of TEAs from 27 boreal catchments differing in land cover (percentage of agricultural land, peatland, forest, and built-up area) during the years 2000–2011.

Landslide susceptibility assessment in Limbe (SW Cameroon): A field calibrated seed cell and information value method

Journal Articles & Books
Décembre, 2012

The dissected volcanic terrains around Limbe, SW Cameroon are frequently affected by small scale but destructive landslides. In this study, a raster-based data driven method involving seed cells is used to build a landslide susceptibility model for the Limbe area. Factors considered to be potential controls of slope failure within this area include slope gradient, rock type, distance from roads, slope orientation, mean annual precipitation, soil type, land cover type, stream density and distance from stream.

Upstream-to-downstream changes in nutrient export risk

Journal Articles & Books
Décembre, 2003

Nutrient export coefficients are estimates of the mass of nitrogen (N) or phosphorus (P) normalized by area and time (e.g., kg/ha/yr). They have been estimated most often for watersheds ranging in size from 10² to 10⁴ hectares, and have been recommended as measurements to inform management decisions. At this scale, watersheds are often nested upstream and downstream components of larger drainage basins, suggesting nutrient export coefficients will change from one subwatershed to the next. Nutrient export can be modeled as risk where lack of monitoring data prevents empirical estimation.

nearest-neighbor imputation approach to mapping tree species over large areas using forest inventory plots and moderate resolution raster data

Journal Articles & Books
Décembre, 2012
États-Unis d'Amérique

The paper describes an efficient approach for mapping multiple individual tree species over large spatial domains. The method integrates vegetation phenology derived from MODIS imagery and raster data describing relevant environmental parameters with extensive field plot data of tree species basal area to create maps of tree species abundance and distribution at a 250-m pixel size for the entire eastern contiguous United States.