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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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Urban green-cover and the environmental performance of Chennai city

Journal Articles & Books
Décembre, 2011
Inde

Chennai city the capital of Tamil Nadu is located in southeastern India. Its average population growth rate is 25% per decade, which recurrently alters the city's land-cover particularly the receding green-cover distressed the city's self-renewal capacity, in terms of groundwater recharge, pollution sequestration and microclimatic amelioration. This has been appraised by means of a GIS model. This model was developed using three sets of green-cover associated parameters, namely air quality amelioration, hydrological process regulation and microclimatic amelioration.

Irish Forest Soils Project and its Potential Contribution to the Assessment of Biodiversity

Journal Articles & Books
Décembre, 2002
Irlande

The United Nations Environment Programme (UNEP) has proposed methods and thematic areas for data collection that are appropriate to the evaluation of biodiversity. The Heritage Council has identified a paucity of data on habitats in Ireland. Within this context, we outline the Irish Forest Soils (IFS) element of the Forest Inventory and Planning System (FIPS) and present a detailed account of land-cover mapping, which is an important aspect of the project.

Size-dependent pattern of wildfire ignitions in Portugal: when do ignitions turn into big fires

Journal Articles & Books
Décembre, 2010
Portugal

Not all wildfire ignitions result in burned areas of a similar size. The aim of this study was to explore whether there was a size-dependent pattern (in terms of resulting burned area) of fire ignitions in Portugal. For that purpose we characterised 71,618 fire ignitions occurring in the country in the period 2001-2003, in terms of population density in the local parish, land cover type and distance to roads. We then assigned each ignition into subsets of five classes according to the resulting burned area: >5 ha, >50 ha, >100 ha, >250 ha, >500 ha.

Geographic bias of field observations of soil carbon stocks with tropical land-use changes precludes spatial extrapolation

Journal Articles & Books
Décembre, 2011

Accurately quantifying changes in soil carbon (C) stocks with land-use change is important for estimating the anthropogenic fluxes of greenhouse gases to the atmosphere and for implementing policies such as REDD (Reducing Emissions from Deforestation and Degradation) that provide financial incentives to reduce carbon dioxide fluxes from deforestation and land degradation. Despite hundreds of field studies and at least a dozen literature reviews, there is still considerable disagreement on the direction and magnitude of changes in soil C stocks with land-use change.

Classification of heathland vegetation in a hierarchical contextual framework

Journal Articles & Books
Décembre, 2013
Belgique

Heathlands in Western Europe have shown dramatic declines over the last century and therefore have been given a high conservation priority in the Habitats Directive of the European Union (EU). Accurate surveying and monitoring of heathland habitats is essential for appropriate conservation management, but the large heterogeneity of vegetation types within habitats as well as the occurrence of similar vegetation across habitat types hinders a straightforward, automated mapping based on aerial images.

Visual complexity and the montado do matter: landscape pattern preferences of user groups in Alentejo, Portugal

Journal Articles & Books
Décembre, 2014
Portugal

• CONTEXT : The current paradigms for the sustainable development of forests and agriculture involve territorial organization of these activities as well as the multifunctionality of the related landscapes. Accordingly, the new management strategies need to take into account the suitability of the resulting landscapes to produce the goods and services expected by society. • AIMS : The aim of the study was to assess the preferred landscape patterns by different groups of users.

High N₂O emissions in dry ecosystems

Journal Articles & Books
Décembre, 2013

Denitrification is an anaerobic respiration that reduces nitrogen (N) oxides (NO₃ ⁻, NO₂ ⁻) to N gases (N₂O, N₂). Our hypothesis suggests that this process might be an important process in depleting nitrogen in dryland soils, based on the idea that the intensity of microbial respiration following infrequent rainfall events and floods, is high enough to deplete soil O₂ concentrations and allow denitrification to occur. We tested our hypothesis by analyses of soil surface samples, collected along a rainfall gradient.

Potential to expand sustainable bioenergy from sugarcane in southern Africa

Journal Articles & Books
Décembre, 2011
Afrique

The Cane Resources Network for Southern Africa evaluated how bioenergy from sugarcane can support sustainable development and improve global competitiveness in the region. The assessment of six countries with good contemporary potential for expanding sugarcane cultivation described in this paper was part of their analysis. Its principal objective was to identify land where such production will not have detrimental environmental and/or socio-economic impacts.

Human activities directly alter watershed dissolved silica fluxes

Journal Articles & Books
Décembre, 2012
États-Unis d'Amérique

Controls on chemical weathering, such as bedrock geology, runoff, and temperature, are considered to be the primary drivers of Si transport from the continents to the oceans. However, recent work has highlighted terrestrial vegetation as an important control over Si cycling. Here we show that at the regional scale (Southern New England, USA), land use/land cover (LULC) is an important variable controlling the net transport of Si from the land to the sea, accounting for at least 40% of dissolved Si (DSi) fluxes.

Ecology of Prestige in New York City: Examining the Relationships Among Population Density, Socio-economic Status, Group Identity, and Residential Canopy Cover

Journal Articles & Books
Décembre, 2014

Several social theories have been proposed to explain the uneven distribution of vegetation in urban residential areas: population density, social stratification, luxury effect, and ecology of prestige. We evaluate these theories using a combination of demographic and socio-economic predictors of vegetative cover on all residential lands in New York City. We use diverse data sources including the City’s property database, time-series demographic and socio-economic data from the US Census, and land cover data from the University of Vermont’s Spatial Analysis Lab (SAL).

time series for monitoring vegetation activity and phenology at 10-daily time steps covering large parts of South America

Journal Articles & Books
Décembre, 2011
Amérique du Sud

It is widely accepted that natural resources should only be sustainably exploited and utilized to effectively preserve our planet for future generations. To better manage the natural resources, and to better understand the closely linked Earth systems, the concept of Digital Earth has been strongly promoted since US Vice President Al Gore's speech in 1998. One core element of Digital Earth is the use and integration of remote sensing data.