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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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Sample-based estimation of “contagion metric” using line intersect sampling method (LIS)

Journal Articles & Books
Décembre, 2015
Suède

Quantification of landscape pattern is of primary interest in landscape ecological studies. For quantification purposes, a large number of landscape metrics have been developed, with definitions based on measurable patch attributes. Calculation of these metrics is commonly conducted on wall-to-wall maps, whereas a new interest is to use sample data. It is argued that a sample survey takes less time and results are more reliable. The overall objective in this paper was to present the potential of the line interest sampling method for estimating a special contagion metric.

Case Study in Large-scale Wetland Restoration at Seney National Wildlife Refuge, Upper Michigan, U.S.A

Journal Articles & Books
Décembre, 2013

A large wetland drainage project was initiated in 1912 near the town of Seney, Michigan, U.S.A. This project included the construction of a series of ditches through a large peatland to drain the land for agricultural use. The largest of these ditches was the 35 km long Walsh Ditch. Much of the drained wetland affected by the Walsh Ditch is now managed by the U.S. Fish and Wildlife Service as part of Seney National Wildlife Refuge.

Persistence and habitat associations of Purple Martin roosts quantified via weather surveillance radar

Journal Articles & Books
Décembre, 2016
Amérique septentrionale

CONTEXT: Weather surveillance radars (WSR) have been used to locate roost sites used by Purple Martins (Progne subis) for decades. Improvements in radar data processing and accessibility now make it possible to monitor roosts over a broad spatial scale. OBJECTIVES: We sought to locate all of the Purple Martin roosts in North America and to use the data to evaluate (1) the land cover types associated with roosts (2) relationships among roost persistence, land cover type, and regional population trends.

Importance of Agricultural Landscapes as Key Nesting Habitats for the American Black Duck in Maritime Canada

Journal Articles & Books
Décembre, 2012

Given historical patterns of decline, the American Black Duck (Anas rubripes) has long been a species of concern. To support the identification of core Maritime habitat, the distribution of breeding ducks was mapped at the landscape scale through the combination of GIS-based land cover information and five years of intensive aerial surveys (2006–2010). A predictive, mixed effects model was used to generate the maps, based on the weighted average of coefficients for the top 95% of all-possible models (as measured by AIC weights).

Convergence of microclimate in residential landscapes across diverse cities in the United States

Journal Articles & Books
Décembre, 2016
États-Unis d'Amérique

CONTEXT: The urban heat island (UHI) is a well-documented pattern of warming in cities relative to rural areas. Most UHI research utilizes remote sensing methods at large scales, or climate sensors in single cities surrounded by standardized land cover. Relatively few studies have explored continental-scale climatic patterns within common urban microenvironments such as residential landscapes that may affect human comfort.

Spontaneous vegetation succession in disused gravel‐sand pits: Role of local site and landscape factors

Journal Articles & Books
Décembre, 2006
République tchèque

Questions: What is the variability of succession over a large geographical area? What is the relative importance of (1) local site factors and (2) landscape factors in determining spontaneous vegetation succession? Location: Various regions of the Czech Republic, Central Europe. The regions represent two categories characterized by agrarian lowlands, with a relatively warm and dry climate, and predominant woodland uplands with a relatively cold and wet climate. Methods: Gravel‐sand pits ranged in age from 1–75 years since abandonment.

Modelling the impact of land-cover change on potential soil loss in the Taita Hills, Kenya, between 1987 and 2003 using remote-sensing and geospatial data

Journal Articles & Books
Décembre, 2011
Kenya
Afrique

In sub-Saharan Africa, natural vegetation is being transformed into agricultural lands at a fast rate, endangering ecosystem services and increasing soil-loss potential, which may trigger land degradation. For the Taita Hills study area in Kenya, multi-temporal land-cover models of 1987, 1999 and 2003, derived from Satellite Pour l'Observation de la Terre (SPOT) imagery using a multi-scale segmentation/object relationship modelling (MSS/ORM) methodology and a rainfall layer, a digital elevation model (DEM) and a digital soil map were applied to model potential soil loss.

Development of a sub-pixel analysis method applied to dynamic monitoring of floods

Journal Articles & Books
Décembre, 2012

Traditional ‘in situ’ measurement techniques often fail to record the spatial distribution of floodplains. In that case, remote sensing provides inexpensive and reliable methodologies to map flooded areas and compute flood damage. The identification and monitoring of floods, due to their highly dynamic nature, require the use of high-time-resolution satellite images with the drawback that such images usually have low to medium spatial resolution.

Suitable, reachable but not colonised: seasonal niche duality in an endemic mountainous songbird

Journal Articles & Books
Décembre, 2014

The realized distribution of animals is often delimited by climatic factors which define, next to the specific habitat and food availability, their species-specific potential distribution. We studied the environmental limitations affecting the realized breeding and wintering distributions of the Citril Finch (Carduelis citrinella), one of the few endemic bird species of European mountain ranges. To assess the environmental limits that shape the seasonal distribution, we used species distribution models (SDMs) derived from macroclimate in combination with land cover information.

Prioritization of Sub-watersheds in Khanapara–Bornihat Area of Assam–Meghalaya (India) Based on Land Use and Slope Analysis Using Remote Sensing and GIS

Journal Articles & Books
Décembre, 2012
Inde

Improper utilization of natural resources without any conservation work is the prime cause of the watershed deterioration. Fast developmental activities and population pressure in the hills of Khanapara–Bornihat area near Guwahati city (about 10 km east of Guwahati) results rapid alteration of the land use/land cover in the recent times. This also causes the growth of land use over the unsuitable topography. As a result, there is a general degradation of the natural resources within the area.

Changes in the availability and uses of wild yams according to climatic dryness and land-cover in Western Burkina Faso (West Africa): a joint ecological and ethno-botanical approach using GIS and remote-sensing

Journal Articles & Books
Décembre, 2008

The regional variability in the uses of wild yams is assessed according to their availability in relation with land-use and climatic conditions from the South to the North sudanian sectors in Western Burkina Faso. The study involves field studies and modelling of the geographical distribution of yams and seeks correlations between environmental and ethno-biological data. Terrain analysis consists of phyto-ecological surveys and interviews with local inhabitants. A cluster analysis of a multi-date image of data obtained by remote-sensing is used to assess land-cover.