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Issuescouverture du solLandLibrary Resource
There are 2, 239 content items of different types and languages related to couverture du sol on the Land Portal.

couverture du sol

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Projected robust shift of climate zones over West Africa in response to anthropogenic climate change for the late 21st century

Journal Articles & Books
Décembre, 2016
Guinée
Afrique occidentale

The response of West African climate zones to anthropogenic climate change during the late 21st century is investigated using the revised Thornthwaite climate classification applied to ensembles of CMIP5, CORDEX, and higher-resolution RegCM4 experiments (HIRES). The ensembles reproduce fairly well the observed climate zones, although with some notable discrepancies. CORDEX and HIRES provide realistic fine-scale information which enhances that from the coarser-scale CMIP5, especially in the Gulf of Guinea encompassing marked landcover and topography gradients.

Hydrologic responses to land cover change: the case of Jedeb mesoscale catchment, Abay/Upper Blue Nile basin, Ethiopia

Journal Articles & Books
Décembre, 2014
Éthiopie

The objective of this study was to quantify the impacts of land use/land cover (LULC) change on the hydrology of the Jedeb, an agricultural dominated mesoscale catchment, in the Abay/Upper Blue Nile basin, Ethiopia. Two methods have been used. First, the trends of certain daily flow variability parameters were evaluated to detect statistical significance of the change of the hydrologic response. Second, a conceptual monthly hydrological model was used to detect changes in the model parameters over different periods to infer LULC change.

Evaluating urban land cover change in the Hurghada area, Egypt, by using GIS and remote sensing

Journal Articles & Books
Décembre, 2012
Égypte

The rapid urban development in the Hurghada area since the 1980s has dramatically enhanced the potential impact of human activities. To inventory and monitor this urban development effectively, remote sensing provides a viable source of data from which updated land cover information can be extracted efficiently and cheaply.

Definition of British Water Beetle Species Pools (Coleoptera) and their Relationship to Altitude, Temperature, Precipitation and Land Cover Variables

Journal Articles & Books
Décembre, 2006

Pooled water beetle species lists from 1826 British national grid 10-km squares were analysed using multivariate ordination and classification methods. The relationships of pool groups to the climate, altitude and land cover variables were assessed using constrained and partial ordinations. Ordination of the species pool data indicated a major trend between squares in the north-west of Scotland and those in southern England, illustrating differences in acid and basic water standing water. Secondary variation was from acid standing water to fast-flowing streams and rivers.

Centrarchid Assemblages in Floodplain Lakes of the Mississippi Alluvial Valley

Journal Articles & Books
Décembre, 2013
Amérique septentrionale

The family Centrarchidae is a principal and visible component of the ichthyofauna in most warmwater ecosystems in North America, and many of its species provide key recreational fisheries. We examined the significance of various local environmental factors to 13 centrarchid species in 53 floodplain lakes (remnant channels) of the Mississippi alluvial valley to identify major environmental gradients influential in structuring centrarchid assemblages.

Macrophytes in shallow lakes: Relationships with water, sediment and watershed characteristics

Journal Articles & Books
Décembre, 2013

We examined macrophyte–environment relationships in shallow lakes located within the Prairie Parkland and Laurentian Mixed Forest provinces of Minnesota. Environmental variables included land cover within lake watersheds, and within-lake, water and sediment characteristics. CCA indicated that sediment fraction smaller than 63μm (f

Evapotranspiration models of different complexity for multiple land cover types

Journal Articles & Books
Décembre, 2012

A comparison between half-hourly and daily measured and computed evapotranspiration (ET) using three models of different complexity, namely, the Priestley–Taylor (P-T), the reference Penman–Monteith (P-M) and the Common Land Model (CLM), was conducted using three AmeriFlux sites under different land cover and climate conditions (i.e. arid grassland, temperate forest and subhumid cropland).

Discrete classification approach to land cover and land use change identification based on Landsat image time sequences

Journal Articles & Books
Décembre, 2014
Ghana

Dense multi-temporal stacks of Landsat imagery have most commonly been exploited to identify land cover and land use changes (LCLUC) based on detection of abrupt changes in continuous value spectral indices. In this study, a discrete classification approach to LCLUC identification based on stable training sites is tested on a nine-date, 4-year Landsat-7 ETM + time sequence for a study area in Ghana that is prone to cloud cover.

Environmental and land use determinants of grassland patch diversity in the western and eastern Alps under agro-pastoral abandonment

Journal Articles & Books
Décembre, 2016

Agro-pastoral decline in European mountain areas has recently caused changes to traditional landscapes with negative consequences on semi-natural grassland conservation and the associated biodiversity and ecosystem services. In the Italian Alps, grassland patches enclosed in a forest matrix are progressively disappearing. Two alpine valleys (Pesio and Pejo), having similar land-use history, were chosen as representative of management conditions of western and eastern Italian Alps, respectively.

Gypsy moth response to landscape structure differs from neutral model predictions: implications for invasion monitoring

Journal Articles & Books
Décembre, 2007

Simulations of dispersal across computer-generated neutral landscapes have generated testable predictions about the relationship between dispersal success and landscape structure. Models predict a threshold response in dispersal success with increasing habitat fragmentation. A threshold is defined as an abrupt, disproportionate decline in dispersal success at a certain proportion of habitat in the landscape.

Predictive spatial niche and biodiversity hotspot models for small mammal communities in Alaska: applying machine-learning to conservation planning

Journal Articles & Books
Décembre, 2015

CONTEXT: Changing global environmental conditions, especially at northern latitudes, are threatening to shift species distributions and alter wildlife communities. OBJECTIVE: We aimed to establish current distributions and community arrangements of small mammals to provide important baselines for monitoring and conserving biodiversity into the future. METHODS: We used 4,408 archived museum and open-access records and the machine learning algorithm, RandomForests, to create high-resolution spatial niche models for 17 species of rodents and shrews in Alaska.