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  • Influence of vegetation cover on sand transport by wind : field studies at Owens Lake, California
  • Aeolian features ; Aeolian transport ; California ; Delta ; Dune ; Erosion control ; Model ; Plant cover ; United States of America ; Vegetation ; Wind erosion ; Wind speed
  • Field studies conducted at Owens Lake, California, provide direct measurements of sand flux on sand sheets with zero to 20 per cent cover of salt grass. The results are reported here. A general empirical model provide for the relation between sand
  • flux and vegetation cover has been derived and can be used to predict the amount of vegetation required to stabilize sand dune areas.
  • 1998
  • Biomass ; Data processing ; Krigeage ; Plant cover ; Remote sensing ; Sampling ; Spatial variation ; Statistics ; Thematic mapping ; Vegetation
  • data and ground data; and to increase the accuracy with wich remotely sensed data can be used to classify land cover or estimate continuous variables. This article introduces these applications and uses 2 examples to highlight characteristics
  • 1998
  • Effects of vegetation cover on soil heat flux in the southern Yukon Territory
  • Canada ; Heat flow ; Plant canopy ; Plant species ; Radiation ; Soil temperature ; Temperature ; Yukon
  • 1998
  • This paper investigates the relationship between the plant cover and the soil aggregate stability. The aggregate stability is measured using the Modified Emerson Water Dispersion Test (MEWDT), water-drop impacts (CND and TDI) and Ultrasonic
  • Disruption (UD) methods on soils from north-facing slopes of the mountain range of La Serra Grossa in the eastern Iberian Peninsula. Soils with similar characteristics but covered by the main plant species at the study area were selected. In order to get
  • 1998
  • Land-cover dynamics in Africa. Observations by remote sensing and spatial modelling
  • Africa ; Deforestation ; Drought ; Geographical information system ; Model ; Plant cover ; Remote sensing ; Satellite imagery ; Spatial analysis ; Vegetation ; Vegetation dynamics
  • 1998
  • Drought ; Estremadura (Spain) ; Land use ; Plant canopy ; Rainfall simulation ; Rill wash ; Soil ; Soil properties ; Soil water ; Spain ; Vegetation
  • Soil hydrology was investigated, during a drought period, in the Guadelperalón experimental watershed in order to determine the influence of land use and vegetation cover on runoff and infiltration within the Deseha land system. Five soil-vegetation
  • units were selected : tree cover, sheep trials, shrub cover, hillslope grass and bottom grass. The importance of the soil water repellency on surface runoff generation is highlighted.
  • 1998
  • Australia ; Cattle ; Ecosystem ; Erosion rate ; Gully erosion ; Impact ; New South Wales ; New Zealand ; Over-grazing ; Plant cover ; Soil erosion ; Temperate zone ; United Kingdom
  • : creation of bare soil by grazing animals; maintenance and expansion of area of bare soil by grazing animals; threshold vegetation cover and erosion; threshold grazing intensities and erosion; rates of erosion of grazed land; grazing, increased runoff
  • 1998
  • Agro-pastoralism ; China ; Ecosystem ; Geographical information system ; Land use ; Man-environment relations ; Plant canopy ; Population ; Population density ; Population distribution ; Tibet
  • The study focuses on the meso-regional pattern of rangeland ecotypes in relation to population density. Data on rangelands derive from a recent land-cover GIS database of China based on the 1:1 000 000 Land Use Map of China. The methodology offers
  • a finer geographic resolution than in all other available research reports. Systemic land cover patterns are mapped, and reveal the importance of local interactions between population and rangeland ecotypes.
  • 1998
  • Applied climatology ; Aridity ; California ; Climatic index ; Drought ; Irrigation ; Land use ; Plant cover ; United States of America ; Water management ; Watershed
  • cover/use situation, thus enlarging the range considered for the classical de martonne index categories. The final goal of this approach is to facilitate a more comprehensive consideration of diversification in water- and land-resource planning
  • 1998
  • Arid area ; Aridity ; Biodiversity ; Duricrust ; Ecosystem ; Israel ; Mediterranean climate ; Plant cover ; Slope exposure ; Spatial variation ; Vegetation
  • possible future soil surface cover changes as a result of climate changes.
  • 1998
  • Belgium ; Image processing ; Landscape ; Map ; Plant cover ; Polder ; Remote sensing ; SPOT
  • 1998
  • Erosion ; Forest fire ; Huesca ; Methodology ; Middle mountain ; Model ; Mountain ; Plant cover ; Pyrénées ; Spain ; Vegetation ; Vegetation index
  • 1998
  • Aeolian deflation ; Aeolian features ; Anatolia ; Climatic variation ; Dune ; Holocene ; Land use ; Palaeo-environment ; Palaeolake ; Plant cover ; Pleistocene ; Turkey
  • 1998
  • Africa ; Desertification ; Geographical information system ; Plant cover ; Remote sensing ; Sahel ; West Africa
  • 1998
  • Arid area ; Chile ; Desertification ; Forecast ; Index ; Model ; Plant cover ; Remote sensing ; SPOT ; Soil degradation ; Spectral analysis ; Thematic mapping ; Vegetation degradation
  • 1998
  • European snow cover and its influence on spring and summer temperatures
  • Albedo ; Climate ; Europe ; Radiation ; Snow ; Snow cover ; Spring ; Summer ; Surface temperature ; Temperature ; Thermal anomaly
  • European surface temperatures in late Spring and early Summer were examined in relation to European snow cover using satellite-derived monthly snow-cover data and station temperatures anomalies. Maximum annual snow extent and March snow extent were
  • correlated with temperature anomalies from April to July. Maximum annual snow-cover extent, which occurred in January or February, was significantly negatively correlated with temperature in the Spring and early Summer. Three distinct regions emerged as being
  • correlated with variation in maximum annual snow cover. These were Central Europe, Western Europe and Eastern Europe in April, May and July respectively.
  • 1998
  • Conservation of soil moisture by different stone covers on alpine talus slopes (Lassen, California)
  • This study reports on the influence of stone covers with different clast sizes on the soil moisture of alpine talus slopes in Lassen. Fifteen four-plot sets were sampled in the dry season (July 1990) in sandy areas and in talus covered with pebbles
  • the moisture conditions found in bare talus and under stone covers; and monitor evaporation losses from these experimental plots for an extended time period.
  • 1998
  • Incoming longwave radiation enhancement by cloud cover
  • The effect of cloud cover on incoming longwave radiation reaching the ground surface is investigated using an analytic procedure. Results show that the contribution of a cloud deck depends not only on cloud type, but also on cloudless emissivity
  • 1998
  • A rock glacier/debris-covered glacier system at Galena Creek, Absaroka Mountains, Wyoming
  • At Galena Creek, the ice/debris system has alternated between rock glacier and debris-covered glacier modes due to changes in the size of the accumulation area. These results have important implications for paleoclimatic studies of the ice
  • 1998
  • Probabilistic, maximal covering location-allocation models for congested systems
  • 1998