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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 the use of ecological heterogeneity to design reserve networks: a case study from Dadia National Park, Greece

Journal Articles & Books
Décembre, 2010
Grèce

In this paper, we present a novel approach for using ecological heterogeneity in reserve design. We measured five ecological heterogeneity indices (EHI) and we used a database of six biological groups (woody plants, orchids, orthopterans, aquatic and terrestrial herpetofauna and passerine birds) across 30 sites in a Mediterranean reserve (Greece). We found that all the five EHI were significantly related to the overall species richness and to the species richness of woody plants and birds.

Hierarchical classification of stream condition: a house–neighborhood framework for establishing conservation priorities in complex riverscapes

Journal Articles & Books
Décembre, 2013

Despite improved understanding of how aquatic organisms are influenced by environmental conditions at multiple scales, we lack a coherent multiscale approach for establishing stream conservation priorities in active coal-mining regions. We classified watershed conditions at 3 hierarchical spatial scales, following a house–neighborhood–community approach, where houses (stream segments) are embedded within neighborhoods (Hydrologic Unit Code [HUC]-12 watersheds) embedded within communities (HUC-10 watersheds).

Weather and Land Cover Influences on Mosquito Populations in Sioux Falls, South Dakota

Journal Articles & Books
Décembre, 2011

This study compared the spatial and temporal patterns of Culex tarsalis Coquillett and Aedes vexans Meigen populations and examined their relationships with land cover types and climatic variability in Sioux Falls, SD. Between 24 and 30 CDC CO2-baited light traps were set annually in Sioux Falls from May to September 2005–2008. Land cover data were acquired from the 2001 National Land Cover Dataset and the percentages of selected land cover types were calculated within a 600-m buffer zone around each trap. Meteorological information was summarized from local weather stations. Cx.

Spatio-temporal variability of streamflow in the Yellow River: possible causes and implications

Journal Articles & Books
Décembre, 2012
Chine

The water shortage in the Yellow River, China, has been aggravated by rapid population growth and global climate changes. To identify the characteristics of streamflow change in the Yellow River, approximately 50 years of natural and observed streamflow data from 23 hydrological stations were examined. The Mann-Kendall and Pettitt tests were used to detect trends and abrupt change points.

Effects of grassland restoration programs on ecosystems in arid and semiarid China

Journal Articles & Books
Décembre, 2013
Chine

We explored the ecological effects of grassland restoration programs using satellite imagery and field plots sampling data and analyzing the patterns and mechanisms of land cover change and vegetation activities in arid and semiarid China during the period from 1982 to 2008. The grassland cover in the 1980s, 2000 and 2005 was compared before and after the restoration programs. The variability of net primary production (NPP) and rain use efficiency (RUE) were analyzed as indicators of vegetation productivity.

Native plants are the bee’s knees: local and landscape predictors of bee richness and abundance in backyard gardens

Journal Articles & Books
Décembre, 2014

Urban gardens may support bees by providing resources in otherwise resource-poor environments. However, it is unclear whether urban, backyard gardens with native plants will support more bees than gardens without native plants. We examined backyard gardens in northwestern Ohio to ask: 1) Does bee diversity, abundance, and community composition differ in backyard gardens with and without native plants? 2) What characteristics of backyard gardens and land cover in the surrounding landscape correlate with changes in the bee community?

Climate sensitivity to tropical land surface changes with coupled versus prescribed SSTs

Journal Articles & Books
Décembre, 2005
Afrique

Tropical land cover change experiments with fixed sea-surface temperatures (SSTs) and with an interactive ocean are compared to assess the relevance of including the ocean system in sensitivity studies to land surface conditions. The results show that the local response to deforestation is similar with fixed and simulated SSTs. Over Amazonia, all experiments simulate a comparable decrease in precipitation and no change in moisture convergence, implying that there is only a change in local water recycling.

partial order approach for summarizing landscape quality

Journal Articles & Books
Décembre, 2003

We propose a simple mathematical framework to define consistently the environmental quality of a given landscape based on the relative abundances of the constituting land cover classes. Unlike traditional diversity measures, the new method does not evaluate the simple dispersion of the relative abundances of land cover classes, but assigns a weight to each land cover class according to the rank along a gradient of environmental quality.

How does the landscape context of occurrence data influence models of invasion risk? A comparison of independent datasets in Massachusetts, USA

Journal Articles & Books
Décembre, 2014
États-Unis d'Amérique

The spatial distribution of non-native, invasive plants on the landscape is strongly influenced by human action. People introduce non-native species to new landscapes and regions (propagule pressure) as well as increase ecosystem invasibility through disturbance of native ecosystems. However, the relative importance of different landscape drivers of invasion may vary with landscape context (i.e., the types and amounts of surrounding land cover and land use). If so, data collected in one context may not be appropriate for predicting invasion risk across a broader landscape.

Objective sampling design in a highly heterogeneous landscape - characterizing environmental determinants of malaria vector distribution in French Guiana, in the Amazonian region

Journal Articles & Books
Décembre, 2013
Guyane française

BACKGROUND: Sampling design is a key issue when establishing species inventories and characterizing habitats within highly heterogeneous landscapes. Sampling efforts in such environments may be constrained and many field studies only rely on subjective and/or qualitative approaches to design collection strategy. The region of Cacao, in French Guiana, provides an excellent study site to understand the presence and abundance of Anopheles mosquitoes, their species dynamics and the transmission risk of malaria across various environments.

Criterion definition for the identification of physical-geographical boundaries of Khorezm oasis through remotely sensed data

Journal Articles & Books
Décembre, 2016
Asie

The Khorezm oasis is one of the main ancient agricultural and cultural centers of Asia. Different studies have used administrative boundaries, without regard to the ecosystem complexity. Remote sensing is a technique that provides many advantages in relation to traditional land cover monitoring approaches. The main objective of this study was to identify the physical-geographical boundaries of Khorezm oasis and analyzed area change dynamics of the oasis using remote sensing data.

Climate change‐linked range expansion of Nathusius' pipistrelle bat, Pipistrellus nathusii (Keyserling & Blasius, 1839)

Journal Articles & Books
Décembre, 2010
Royaume-Uni
Europe

Aim To examine the effect of climate change on the occurrence and distribution of Pipistrellus nathusii (Nathusius' pipistrelle) in the United Kingdom (UK). Location We modelled habitat and climatic associations of P. nathusii in the UK and applied this model to the species' historical range in continental Europe. Methods A binomial logistic regression model was constructed relating the occurrence of P. nathusii to climate and habitat characteristics using historical species occurrence records (1940-2006) and CORINE land cover data.