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  • Satellite-based quantification of tree-dominated pasture degradation stages in north-eastern Pará, Brazil
  • Brazil ; Forest ; Pará ; Pastureland ; Satellite imagery ; Vegetation ; Vegetation degradation
  • Brésil ; Dégradation de la végétation ; Forêt ; Image satellite ; Pará ; Pâturage ; Végétation
  • The analysis of the satellite imagery suggested that degradation of pastures were probably underestimated in the past because a considerable part of previous studies classified degrading pastures as secondary forests. Therefore, future climate
  • and carbon models should include a more exact analysis of tree-dominanted pastures to get a more detailed picture of reality. The paper deals with Bragantina, Capoeira, Juquira, pasture degradation, bush encroachment and satellite image classification. - (IfL)
  • An assessment of land degradation in the Northern Province from satellite remote sensing and community perception
  • Biomass ; Desertification ; LANDSAT ; MSS ; Perception ; Remote sensing ; Soil degradation ; Soil erosion ; South Africa ; Vegetation ; Vegetation index
  • Afrique du Sud ; Biomasse ; Dégradation des sols ; Désertification ; Erosion des sols ; Indice de végétation ; LANDSAT ; MSS ; Northern Transvaal ; Perception ; Télédétection ; Végétation
  • The assessment of land degradation in developing rural areas of South Africa is often hampered by a lack of reliable data. Remote sensing data offers a reliable source of information. In a case study in the Sekgosese district in northern South
  • Africa, the findings coincided with local community perceptions, although most people were unaware of the causes and effects of land degradation. - (AJC)
  • Simulating icelandic vegetation cover during the Holocene implications for long-term land degradation
  • Birch ; Climatic variation ; Forest ; Holocene ; Human impact ; Human occupation ; Iceland ; Model ; Palaeo-environment ; Palynology ; Simulation ; Vegetation ; Vegetation degradation
  • Action anthropique ; Bouleau ; Dégradation de la végétation ; Forêt ; Holocène ; Islande ; Modèle ; Occupation humaine ; Palynologie ; Paléo-environnement ; Simulation ; Variation climatique ; Végétation
  • The AA. have simulated the spatial relationship between temperature change and long-term potential vegetation cover dynamics. The results show that the potential vegetation and birch forest range is highly sensitive to the temperature conditions
  • Grassland degradation in the Three-River Headwaters region, Qinghai Province
  • Biogeography ; China ; Grassland ; Qinghai ; Remote sensing ; Satellite imagery ; Spatial variation ; Vegetation degradation ; Vegetation index ; Years 1970-79 ; Years 1990-99
  • Années 1970 ; Années 1990 ; Biogéographie ; Chine ; Date 2004 ; Dégradation de la végétation ; Formation herbacée ; Image satellite ; Indice de végétation ; Qinghai ; Télédétection ; Variation spatiale
  • In order to acquire objectively spatial-temporal processes of grassland degradation, MSS images in the mid and late 1970s, TM images in the early 1990s and TM/ETM images in 2004 were used. Grassland degradation in the Three-River Headwaters (TRH
  • ) region was interpreted through analysis on RS images in 2 time series, then the spatial and temporal characteristics of grassland degradation in the TRH region were analyzed since the 1970s. Because grassland degradation had obviously regional differences
  • in the TRH region, it could be regionalized into 7 zones, and each zone had different characteristics in type, grade, scale and time process of grassland degradation.
  • Characterising vegetation cover in relation to land use in the Inkomati catchment, South Africa, using Landsat imagery
  • Environment ; Image analysis ; Mpumalanga ; Productivity ; South Africa ; Vegetation ; Vegetation degradation ; Vegetation map ; Watershed
  • Afrique du Sud ; Analyse d'image ; Bassin-versant ; Carte de la végétation ; Dégradation de la végétation ; Environnement ; Mpumalanga ; Productivité ; Végétation
  • The paper assesses catchment-scale vegetation cover and condition, indicated by land degradation and vegetation vigour. Image classification into vegetation density categories is used in mapping land degradation. It can be mapped with certainty
  • Drought ; Ecological imbalance ; Ecosystem ; Environmental degradation ; Pastureland ; Spain ; Vegetation degradation
  • Dégradation de l'environnement ; Dégradation de la végétation ; Déséquilibre écologique ; Ecosystème ; Espagne ; Pâturage ; Sécheresse
  • Spatial and temporal patterns of vegetation recovery following sequences of forest fires in a Mediterranean landscape, Mt. Carmel Israel
  • Forest fire ; Impact ; Israel ; Mediterranean climate ; Slope ; Soil degradation ; Soil erosion ; Vegetation ; Vegetation degradation
  • Climat méditerranéen ; Dégradation de la végétation ; Dégradation des sols ; Erosion des sols ; Impact ; Incendie de forêt ; Israël ; Régénération ; Versant ; Végétation
  • Etablissement des vitesses de régénération de la végétation pour différentes étendues et sévérités de feux de forêts et pour différents aspects de versants.
  • Grassland degradation in Northern Tibet based on remote sensing data
  • AVHRR ; China ; Grassland ; NOAA ; Remote sensing ; Spatial distribution ; Tibet ; Vegetation degradation ; Vegetation index
  • AVHRR ; Chine ; Distribution spatiale ; Dégradation de la végétation ; Formation herbacée ; Indice de végétation ; NOAA ; Tibet ; Télédétection
  • Policies to reduce tropical deforestation and degradation : a computable general equilibrium analysis for Cameroon
  • Cameroon ; Deforestation ; Forest ; Forest policy ; Numerical model ; Tropical rain forest ; Vegetation degradation ; Wood
  • Bois ; Cameroun ; Déboisement ; Dégradation de la végétation ; Forêt ; Forêt tropicale ; Modèle numérique ; Politique forestière
  • This paper addressed specific questions within the much broader discussion on policies to reduce tropical deforestation and degradation in developing countries. The short-to medium-run consequences of resource policies and trade liberalization
  • Defining degradation : the impacts of swidden on forests in Northern Thailand
  • Environment ; Environmental degradation ; Ethnic community ; Forest ; Land clearing ; Shifting cultivation ; Thailand ; Vegetation dynamics
  • Culture itinérante ; Dynamique de la végétation ; Défrichement ; Dégradation de l'environnement ; Environnement ; Ethnie ; Forêt ; Thaïlande
  • A reevaluation of the usual view that shifting cultivation leads to forest degradation, soil erosion, water shortages, and other undesirable changes. Author examines the swidden farming near three upland villages in northern Thailand. swiddens
  • An assessment of land degradation in the Save catchment of Zimbabwe
  • Environmental degradation ; Geographical information system ; Image analysis ; Land use ; Vegetation dynamics ; Watershed ; Zimbabwe
  • Analyse d'image ; Bassin-versant ; Dynamique de la végétation ; Dégradation de l'environnement ; Système d'information géographique ; Utilisation du sol ; Zimbabwe ; Zimbabwe de l'Est
  • Identification d'espaces susceptibles d'être dégradés. La télédétection et les techniques de SIG sont appliquées au district de Buhera. Données : images Landsat de 1992 et 2002, zonage agro-écologique, couverture végétale et densité de population
  • Well drained soils with a degraded Bt horizon in loess deposits in Belgium| relationship with paleoperiglacial processes
  • Belgique ; Fragipan ; Géographie physique ; Horizon Bt dégradé ; Héritage périglaciaire ; Loess ; Paléopériglaciaire ; Pédogenèse ; Périglaciaire ; Sol ; Zone tempérée
  • The presence of a compact fragipan horizon help to explain the association of the degradation of the soil and the permeability of the substratum. This is possible on basis of the hypothesis which links the fragipan development to ice segregation
  • in permafrost aggrading in an environment with relatively high water supply from the subsoil. The degree of degradation, and its distribution in the landscape, can be explained in a much more satisfactory way by these processes associated with a periglacial
  • climate than by the presence of a particular forest vegetation.
  • Using simulated emergent vegetation to alter stream flow direction within a straight experimental channel
  • Cours d'eau ; Ecoulement fluvial ; Etats-Unis ; Expérimentation ; Géométrie hydraulique ; Mississippi ; Méandre ; Végétation ; Végétation ripicole
  • Channel geometry ; Experimentation ; Meander ; Mississippi ; Riparian vegetation ; Stream ; Stream flow ; United States of America ; Vegetation
  • The aim of this study was to induce the location of the maximum surface velocity or thalweg of a straight, degraded stream channel to meander through the use of managed emergent vegetation. This study showed that flow velocity can be markedly
  • reduced within and near the vegetation zones, flow can be diverted toward the opposite bank, and vegetation density can control the magnitude of these effects. The following discussion will focus on design considerations for stream restoration
  • Logique spatiale de la répartition de la végétation dégradée par la pollution atmosphérique
  • Biological indicator ; Chemical pollution ; European part of Russia ; Pollution ; Saint Petersburg ; Spruce ; Tree ; Vegetation ; Vegetation degradation
  • Arbre ; Bio-indicateur ; Dégradation de la végétation ; Epicéa ; Pollution ; Pollution chimique ; Russie d'Europe ; Sankt-Peterburg ; Végétation
  • Etude de la dégradation de la végétation sous l'effet de la pollution de l'usine chimique de Tosno dans l'oblast de Leningrad. Le tableau 1 rassemble des données sur l'état de peuplements d'épicés commun (Picea abies), le tableau 2 sur la fréquence
  • Effects of permafrost degradation on woody vegetation at arctic treeline on the Seward Peninsula, Alaska
  • Active layer ; Alaska ; Arctic Region ; Climatic warming ; Cold area ; Environmental degradation ; Impact ; Palsa ; Permafrost ; Soil properties ; Thawing ; Thermokarst ; Vegetation
  • Alaska ; Arctique ; Dégel ; Dégradation de l'environnement ; Impact ; Limite forêt-toundra ; Mollisol ; Palse ; Pergélisol ; Propriétés du sol ; Réchauffement climatique ; Thermokarst ; Végétation ; Zone froide
  • This study examines the relationship between vegetation and soil characteristics in an active thaw pond complex on Seward Peninsula in order to determine the mechanistic relationship between thermokarst formation and vegetation change at the forest
  • -tundra boundary. In particular, the AA. address 2 questions : what is the relationship between active-layer thickness, soil drainage, and vegetation? what are the temporal dynamics of tree colonization and mortality in this thaw-pond complex?
  • Land degradation assessment with the aid of geo-information techniques
  • China ; Duricrust ; Geographical information system ; Global Positioning System ; LANDSAT ; Remote sensing ; Shaanxi ; Soil degradation ; Soil erosion ; Thematic Mapper ; Vegetation index
  • Chine ; Dégradation des sols ; Encroûtement ; Erosion des sols ; GPS ; Indice de végétation ; LANDSAT ; Shaanxi ; Système d'information géographique ; Thematic Mapper ; Télédétection
  • This research integrated selected land degradation indicators (vegetation cover, proportion of drifting sand area, desertification rate, and population pressure) with geo-information techniques (remote sensing, geographic information system
  • and global positioning system) to assess the severity of land degradation risk. The northern part of Shaanxi province in China was taken as a case study. Satellite images of the study were acquired in October 1987 and in October 1999 (Landsat TM images). All
  • Effects of anthropogenic disturbances on paramo vegetation in Podocarpus National Park, Ecuador
  • Andes ; Biodiversity ; Biogeography ; Ecology ; Ecosystem ; Ecuador ; Human impact ; Mountain ; Vegetation ; Vegetation degradation ; Vegetation dynamics
  • Action anthropique ; Andes ; Biodiversité ; Biogéographie ; Dynamique de la végétation ; Dégradation de la végétation ; Ecologie ; Ecosystème ; Equateur ; Montagne ; Páramo ; Végétation
  • Environmental degradation ; Human impact ; Mountain ; Natural environment ; Nuisance ; Poland ; Pollution ; Tatra Mountains ; Vegetation ; Vegetation degradation
  • Action anthropique ; Dégradation de l'environnement ; Dégradation de la végétation ; Milieu naturel ; Montagne ; Nuisance ; Pollution ; Pologne ; Tatry ; Végétation
  • The relevance of humus forms for land degradation in Mediterranean mountainous areas
  • Catena ; Forest soil ; Humus ; Infiltration ; Lithology ; Mediterranean climate ; Mountain ; Soil ; Soil degradation ; Soil erosion ; Soil properties ; Spain
  • In the Gavarras (NE Spain), a large number of plots on respective schists, leucogranite and granodiorite was studied for their soils and vegetation. Results are discussed, focusing on properties of humus forms and underlying mineral horizons which
  • are relevant for the susceptibility of these soils to erosion and degradation.
  • Carte des modifications de la végétation dues à l'action anthropique en Pologne
  • Economic activity ; Ecosystem ; Human impact ; Map ; Poland ; Vegetation ; Vegetation degradation
  • Action anthropique ; Activité économique ; Carte ; Dégradation de la végétation ; Ecosystème ; Pologne ; Végétation
  • The presented method of evaluating transformations in vegetational landscapes is based on the concept of rings of successor communities. This serves in the drawing up of the map of anthropogenic transformations of Poland's vegetational landscapes