Passar para o conteúdo principal

page search

Issuescobertura do soloLandLibrary Resource
There are 2, 239 content items of different types and languages related to cobertura do solo on the Land Portal.

cobertura do solo

AGROVOC URI:

Displaying 1165 - 1176 of 1964

Assessment of fire selectivity in relation to land cover and topography: a comparison between Southern European countries

Journal Articles & Books
Dezembro, 2014
Turquia
Chipre

Land cover distribution is one of the factors that influence fire behaviour and its consequences in the landscape. The relation between land cover type and fire was investigated at a broad scale, in order to analyse land cover differences in fire proneness. The selection ratio for nine different land cover categories was calculated for the fire perimeters mapped in Southern Europe between 2000 and 2008. The results obtained were then compared per country and region. The fire proneness of topographic classes and its potential association with land cover types were also assessed.

Tree density and biomass assessment in agricultural systems around Lake Victoria, Uganda

Journal Articles & Books
Dezembro, 2008
Uganda

Soil erosion caused by low vegetation cover associated with agricultural land use in the catchment is blamed for the eutrophication of Lake Victoria. Above-ground biomass as an indicator of vegetation cover and biodiversity was assessed using the Normalized Difference Vegetation Index, estimation of tree density and biomass with the aim of assessing the extent to which vegetation covers the soil surface. Tree density is significantly different between agricultural and semi-natural systems with an average of 96 and 90 trees ha⁻¹ observed in Rakai and Mayuge respectively.

Are Swiss birds tracking climate change? Detecting elevational shifts using response curve shapes

Journal Articles & Books
Dezembro, 2011
Suíça

Climate change is affecting biodiversity worldwide inducing species to either “move, adapt or die”. In this paper we propose a conceptual framework for analysing range shifts, namely a catalogue of the possible patterns of change in the distribution of a species along elevational or other environmental gradients and an improved quantitative methodology to identify and objectively describe these patterns.

On the extent of fire-induced forest degradation in Mato Grosso, Brazilian Amazon, in 2000, 2005 and 2010

Journal Articles & Books
Dezembro, 2016
Brasil

In this paper we analyse the extent of fire-induced forest degradation in Mato Grosso State, Brazil. We utilise a sample based approach used in a previous pan-tropical deforestation survey to derive information on land cover and burned areas in the two major biomes of Mato Grosso: Amazon and Cerrado. Land cover and burned area are mapped for three years (2000–2005–2010) over 77 sample sites (10000ha each) distributed systematically throughout the state which covers 90.337 Mha.

Landscape Composition Weakly Affects Home Range Size in Blanding's Turtles (Emydoidea blandingii)

Journal Articles & Books
Dezembro, 2012

Landscape composition and habitat quality influence the abundance, population structure, and movements of animals. Understanding how an animal interacts with elements of the landscape helps predict its response to habitat loss and changes in land cover. We tested the hypothesis that the extent of movement depends on landscape composition in a threatened freshwater turtle, Emydoidea blandingii. We measured habitat composition at multiple spatial scales, ranging from the home range to the landscape scale.

Global‐scale mapping of changes in ecosystem functioning from earth observation‐based trends in total and recurrent vegetation

Journal Articles & Books
Dezembro, 2015
África
Global
América do Sul

AIM: To evaluate trend analysis of earth observation (EO) dense time series as a new way of describing and mapping changes in ecosystem functioning at regional to global scales. Spatio‐temporal patterns of change covering 1982–2011 are discussed in the context of changes in land use and land cover (LULCC). LOCATION: Global.

Development and mapping of fuel characteristics and associated fire potentials for South America

Journal Articles & Books
Dezembro, 2014
América do Sul

The characteristics and spatial distribution of fuels are critical for assessing fire hazard, fuel consumption, greenhouse gas emissions and other fire effects. However, fuel maps are difficult to generate and update, because many regions of the world lack fuel descriptions or adequate mapped vegetation attributes to assign these fuelbeds spatially across the landscape. This paper presents a process to generate fuel maps for large areas using remotely sensed information and ancillary fuel characteristic data.

Biotic resistance in freshwater fish communities: species richness, saturation or species identity?

Journal Articles & Books
Dezembro, 2015

Some communities are susceptible to invasions and some are not. Why? Elton suggested in 1958 that the ability of the community to withstand invading species – its biotic resistance – depends on the number of resident species. Later contributors have emphasized the habitat's ability to support species, as well as the contribution of individual species to the resistance. In this study we use information from 184 introductions of Arctic char into Swedish lakes to study both abiotic and biotic aspects of the resident community's ability to resist introductions.

Modelling the effect of habitat fragmentation on climate‐driven migration of European forest understorey plants

Journal Articles & Books
Dezembro, 2015
Suíça
Noruega
Europa

AIM: The rate of climate change might exceed the migration capacity of plants, particularly where habitats became fragmented by human land use. Except for some tree species, the extent to which habitat fragmentation decreases migration rates has nevertheless been little evaluated. Here, we compare simulated migration rates of understorey herbs, which comprise the big part of temperate forest plant diversity, under varying levels of fragmentation at a continental scale. LOCATION: Europe.

Environmental and land use determinants of grassland patch diversity in the western and eastern Alps under agro-pastoral abandonment

Journal Articles & Books
Dezembro, 2016

Agro-pastoral decline in European mountain areas has recently caused changes to traditional landscapes with negative consequences on semi-natural grassland conservation and the associated biodiversity and ecosystem services. In the Italian Alps, grassland patches enclosed in a forest matrix are progressively disappearing. Two alpine valleys (Pesio and Pejo), having similar land-use history, were chosen as representative of management conditions of western and eastern Italian Alps, respectively.

Exploitation of TerraSAR-X Data for Land use/Land Cover Analysis Using Object-Oriented Classification Approach in the African Sahel Area, Sudan

Journal Articles & Books
Dezembro, 2013
Sudão

Recently, object-oriented classification techniques based on image segmentation approaches are being studied using high-resolution satellite images to extract various thematic information. In this study different types of land use/land cover (LULC) types were analysed by employing object-oriented classification approach to dual TerraSAR-X images (HH and HV polarisation) at African Sahel. For that purpose, multi-resolution segmentation (MRS) of the Definiens software was used for creating the image objects.