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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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Estimating crop net primary production using national inventory data and MODIS-derived parameters

Journal Articles & Books
Décembre, 2013

National estimates of spatially-resolved cropland net primary production (NPP) are needed for diagnostic and prognostic modeling of carbon sources, sinks, and net carbon flux between land and atmosphere. Cropland NPP estimates that correspond with existing cropland cover maps are needed to drive biogeochemical models at the local scale as well as national and continental scales. Existing satellite-based NPP products tend to underestimate NPP on croplands.

Landscape-scale variability in soil organic carbon storage in the central Canadian Arctic

Journal Articles & Books
Décembre, 2014

Campeau, A. B., Lafleur, P. M. and Humphreys, E. R. 2014. Landscape-scale variability in soil organic carbon storage in the central Canadian Arctic. Can. J. Soil Sci. 94: 477–488. Arctic soils constitute a vast, but poorly quantified, pool of soil organic carbon (SOC). The uncertainty associated with pan-Arctic SOC storage estimates – a result of limited SOC and land cover data – needs to be reduced if we are to better predict the impact of future changes to Arctic carbon stocks resulting from climate warming.

Impact of land‐use changes on soil hydraulic properties of Calcaric Regosols on the Loess Plateau, NW China

Journal Articles & Books
Décembre, 2015
Chine

Vegetation restoration efforts (planting trees and grass) have been effective in controlling soil erosion on the Loess Plateau (NW China). Shifts in land cover result in modifications of soil properties. Yet, whether the hydraulic properties have also been improved by vegetation restoration is still not clear. The objective of this paper was to understand how vegetation restoration alters soil structure and related soil hydraulic properties such as permeability and soil water storage capacity.

Climate, human palaeoecology and the use of fuel in Wadi Sana, Southern Yemen

Journal Articles & Books
Décembre, 2014
Yémen

This study integrates analysis of wood charcoal assemblages with climate proxies, palaeoenvironmental and archaeological data sets in hyper-arid Wadi Sana, Yemen, to address the availability and use of wood fuels by South Arabian hunter-herder groups from the Early Holocene (8000–7700� cal. B.P.) to Middle Holocene (6900–4800� cal. B.P.) periods.

Change detection of sandy land areas in Minfeng oasis of Xinjiang, China

Journal Articles & Books
Décembre, 2009
Chine

In recent years, much attention has been given to desertification in Xinjiang, China, particularly in the southern edge of the Taklimakan Desert. In this study, an oasis in Minfeng County, which is located in the southern edges of the Taklimakan Desert, was chosen as our case study area. Supervised classification for land types was conducted, and then the change detection and the trend of changes in sandy land areas were analyzed and compared. The results show that the area of sandy land has decreased in the region in the period of 1992-2001.

Mapping hotspots of malaria transmission from pre-existing hydrology, geology and geomorphology data in the pre-elimination context of Zanzibar, United Republic of Tanzania

Journal Articles & Books
Décembre, 2015
Tanzania

BACKGROUND: Larval source management strategies can play an important role in malaria elimination programmes, especially for tackling outdoor biting species and for eliminating parasite and vector populations when they are most vulnerable during the dry season. Effective larval source management requires tools for identifying geographic foci of vector proliferation and malaria transmission where these efforts may be concentrated.

Modeling of air pollutant removal by dry deposition to urban trees using a WRF/CMAQ/i-Tree Eco coupled system

Journal Articles & Books
Décembre, 2013

A distributed adaptation of i-Tree Eco was used to simulate dry deposition in an urban area. This investigation focused on the effects of varying temperature, LAI, and NO₂ concentration inputs on estimated NO₂ dry deposition to trees in Baltimore, MD. A coupled modeling system is described, wherein WRF provided temperature and LAI fields, and CMAQ provided NO₂ concentrations. A base case simulation was conducted using built-in distributed i-Tree Eco tools, and simulations using different inputs were compared against this base case.

Multistate modeling of habitat dynamics: factors affecting Florida scrub transition probabilities

Journal Articles & Books
Décembre, 2010

Many ecosystems are influenced by disturbances that create specific successional states and habitat structures that species need to persist. Estimating transition probabilities between habitat states and modeling the factors that influence such transitions have many applications for investigating and managing disturbance‐prone ecosystems. We identify the correspondence between multistate capture–recapture models and Markov models of habitat dynamics.

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).

On the distance travelled for woodland leisure via different transport modes in Wallonia, south Belgium

Journal Articles & Books
Décembre, 2016
Belgique

Based on an extensive survey of woodland visitors in Wallonia, south Belgium, we examined a wide range of individual-, residential- and destination-level variables for their associations with the distance travelled for woodland leisure on foot, by bicycle and by car. For each transport mode, explanatory bivariate analyses were conducted firstly to identify potential correlates of the distances travelled. Then, cross-classified multilevel analysis was performed to build estimation models for the trip distance.

How resilient are African woodlands to disturbance from shifting cultivation?

Journal Articles & Books
Décembre, 2015
Tanzania
Afrique

Large parts of sub‐Saharan Africa are experiencing rapid changes in land use and land cover, driven largely by the expansion of small‐scale shifting cultivation. This practice creates complex mosaic landscapes with active agricultural fields and patches of mature woodland, interspersed with remnant patches in various stages of regrowth.