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

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Environmental heterogeneity as a universal driver of species richness across taxa, biomes and spatial scales

Journal Articles & Books
Décembre, 2014

Environmental heterogeneity is regarded as one of the most important factors governing species richness gradients. An increase in available niche space, provision of refuges and opportunities for isolation and divergent adaptation are thought to enhance species coexistence, persistence and diversification. However, the extent and generality of positive heterogeneity–richness relationships are still debated. Apart from widespread evidence supporting positive relationships, negative and hump‐shaped relationships have also been reported.

Modern pollen and land-use relationships in the Taihang mountains, Hebei province, northern China—a first step towards quantitative reconstruction of human-induced land cover changes

Journal Articles & Books
Décembre, 2013
Chine

Studies of the modern relationship between pollen, vegetation and land-use are essential to infer past human impact on vegetation from pollen records. Nevertheless, such investigations are relatively few in China. We present here a study of pollen assemblages from sediment samples collected from irrigation pools in the Tuoliang and Qipanshan catchments in northern China.

Spatio-temporal Assessment of Urban Heat Island Effects in Kuala Lumpur Metropolitan City Using Landsat Images

Journal Articles & Books
Décembre, 2014

Alteration in climatic pattern has resulted to a steady decline in quality of life and the environment, especially in and around urbanized areas. These areas are faced with increasing surface temperature arising mostly from human activities and other natural sources; hence land surface temperature has become an important variable in global climate change studies. In this paper, Landsat TM/ETM imagery acquired between 1997 and 2013 were used to extract ground brightness temperature and land use/land cover change in Kuala Lumpur metropolis.

Numerical research of extreme wind-induced dust transport in a semi-arid human-impacted region of Mexico

Journal Articles & Books
Décembre, 2011
Mexique

A numerical research is carried out to investigate the regional impact of extreme wind-induced dust transport in the central-northern part of Mexico. In boreal winter, strong wind soil erosion processes occur in the arid zones of the Mexican highlands, as a consequence of land use change and land cover change. The effect of land use change and land cover change has consequences in the atmospheric circulation, by altering the balance in solar radiation, albedo, soil moisture and texture, aerodynamic roughness and other surface properties.

Landscape-level analysis of mountain goat population connectivity in Washington and southern British Columbia

Journal Articles & Books
Décembre, 2015

Habitat fragmentation and habitat loss diminish population connectivity, reducing genetic diversity and increasing extinction risk over time. Improving connectivity is widely recommended to preserve the long-term viability of populations, but this requires accurate knowledge of how landscapes influence connectivity. Detectability of landscape effects on gene flow is highly dependent on landscape context, and drawing conclusions from single landscape studies may lead to ineffective management strategies.

Experience analysis and sample distribution problems in local level landscape monitoring

Conference Papers & Reports
Décembre, 2011
Lettonie
Lituanie

After summarizing experience of various countries in the field of landscape monitoring, it appears that the real changes of landscape have to be observed in a large scale (not smaller than 1:10,000) in order to avoid generalization of small landscape elements.

Soil and climate are better than biotic land cover for predicting home-range habitat selection by endangered burrowing owls across the Canadian Prairies

Journal Articles & Books
Décembre, 2011
Canada

Statistical models that describe species-environmental relationships are important components within many wildlife conservation strategies. These models are typically developed from studies conducted on small geographic scales (hundreds of square kilometres), representing a relatively small range in environmental conditions. Such local models from local studies are often then extrapolated to predict the suitability of other unsampled regions.

The impact of urbanization on the monthly averaged diurnal cycle in October 2004 in the Pearl River Delta region

Journal Articles & Books
Décembre, 2009
États-Unis d'Amérique
Chine

The Pearl River Delta (PRD) region in southern China has experienced rapid urbanization and dramatic economic growth in last 25 years. Using identical observed meteorology for lateral boundary conditions, two one-month simulations were conducted: one using the original United States Geological Survey (USGS) 24-category land cover data (namely NU) and the other using the urban land cover data from 2004 Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images (namely HU) as lower boundary conditions in a mesoscale model.

Coexistence of Introduced and Native Common Reed (Phragmites australis) in Freshwater Wetlands

Journal Articles & Books
Décembre, 2012
Canada

Invasive species are especially problematic when introduced into ecosystems with native congeners. The extent to which niches overlap in space determines whether the introduced species threatens the native one or the native species can escape competition or the effect of control. We compared the spatial distribution in relation to landscape and land-use/ land-cover variables of introduced and native Phragmites australis (common reed) in a landscape of protected freshwater wetlands in Quebec, Canada. Results showed that the wetlands still serve as refuges for native P. australis.

Change of precipitation intensity spectra at different spatial scales under warming conditions

Journal Articles & Books
Décembre, 2013
Chine

The long-term change of the whole spectra of precipitation intensity in China is examined using observed daily data recorded at 477 surface stations for the period from 1961 to 2008. The results show a spatially coherent decrease of trace precipitation despite different reduction magnitudes among the regions. For measurable precipitation, significant regional and seasonal characteristics are observed. In autumn, the whole measurable precipitation decreased over Eastern China (east of 98°E).

Estimating the frequency of extreme rainfall using weather radar and stochastic storm transposition

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

Spatial and temporal variability in extreme rainfall, and its interactions with land cover and the drainage network, is an important driver of flood response. “Design storms,” which are commonly used for flood risk assessment, however, are assumed to be uniform in space and either uniform or highly idealized in time. The impacts of these and other commonly-made assumptions are rarely considered, and their impacts on flood risk estimates are poorly understood.

Shoreline Change Analysis along the Coast of South Gujarat, India, Using Digital Shoreline Analysis System

Journal Articles & Books
Décembre, 2014
Inde

Shoreline changes along the south Gujarat coast has been analyzed by using USGS Digital Shoreline Analysis System (DSAS) version 4.3. Multi-temporal satellite images pertaining to 1972, 1990, 2001 and 2011 were used to extract the shoreline. The High water line (HTL) is considered as shoreline and visual interpretation of satellite imageries has been carried out to demarcate the HTL based on various geomorphology and land use & land cover features. The present study used the Linear Regression Method (LRR) to calculate shoreline change rate.