Biodiversity ; Coastal environment ; Dune ; Ecology ; Georgia (USA) ; Human impact ; Island ; Plantcover ; Taxonomy ; United States of America ; Vegetation
in human-modified areas have lower dune-grass cover and greater cover of species that are not adapted to building and stabilizing dunes. Therefore, human disturbance may indirectly reduce dune stability by altering the dune vegetation.
AVHRR ; China ; Evapotranspiration ; Heat flow ; Model ; NOAA ; North-Western China ; Plantcover ; Radiation ; Remote sensing
In this paper, the evapotranspiration estimation models for dense vegetation and bare soil are presented, based on the information of parameters like vegetation cover-degree and surface albedo. Combined with vegetation cover-degree data, a model
Seasonal land-cover regions of the United States. Map supplement
AVHRR ; Biogeography ; Cultivated land ; Data base ; Forest ; Global change ; NOAA ; Plantcover ; Remote sensing ; Seasonal variation ; Thematic mapping ; United States of America
This paper presents a new classification of U.S. land cover based on AVHRR data. One hundred fifty-nine seasonal land-cover regions are described and mapped according to their vegetative composition, phenology (onset, peak, and length of green
Estimating land cover-induced increases in daytime summer temperatures near Mt. Adams, Washington
Air temperature ; Climatic warming ; Deforestation ; Forest ; Glacier ; Glacier retreat ; Mountain ; Plantcover ; Remote sensing ; Summer ; Temperature ; United States of America ; Washington State
The AA. present an approach for developing a land cover-induced daytime-high-temperature model in an activelly and historically logged terrain west of Mount Adams, Washington, by combining field data of near surface temperatures in young-regrowth
. The model of near-surface temperatures and the temperature differences due to land cover change is discussed in the context of the pootential effects on recent changes in the geometry of Cascades glaciers.
Modelling and monitoring land-cover change processes in tropical regions
Arid area ; Biogeography ; Deforestation ; Desertification ; Ecosystem ; Environment ; Environmental management ; Global change ; Land use ; Landscape dynamics ; Model ; Plantcover ; Spatial analysis ; Tropical zone
. The review highlights the requirement to tailor the investigation method to the specific research question of interest. Different techniques to monitor land-cover changes at regional scales are analysed. The article stresses the needs for a better integration
of social science knowledge in land-cover change models and for a comprehensive theory of land-use changes.
This paper examines the effect of topography on vegetation cover on the mountain ranges, alluvial fans and footslopes of drainage basins in arid central Australia. The AA. use the topographic indices commonly employed in distributed hydrologic
and erosion models as indicators of moisture redistribution and soil loss or accumulation in the landscape. The spatial patterns shown by these indices are compared with the observed distribution of vegetation cover obtained from satellite imagery.
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 ; Plantcover ; 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.
Characterisation of land cover types in Xilin River Basin using multi-temporal Landsat images
China ; Classification ; Inner Mongolia ; LANDSAT ; Land use ; Plant canopy ; Remote sensing ; Thematic Mapper ; Vegetation ; Watershed
This study conducted computer-aided image analysis of land use and land cover in Xilin River Basin, Inner Mongolia, using 4 sets of Landsat TM/ETM+ images acquired on July 31, 1987, August 11, 1991, September 27, 1997 and May 23, 2000, respectively
. Primarily, 17 sub-class land cover types were recognized, including 9 grassland types. To eliminate the classification error existing among different sub-types of the same gross type, the 17 sub-class land cover types were grouped into 5 gross types : meadow
Arid area ; Mediterranean area ; Modelling ; Plant canopy ; Semi-arid area ; Simulation ; Slope gradient ; Soil erosion ; Spain ; Spatial distribution ; Watershed
In this paper the structured spatial distribution of the vegetation cover and associated soil attributes is proposed as one of the possible causes of variation in cover-erosion relationships, in particular in dryland environments where patchy
vegetation covers are common. A simulation approach was used to test the hypothesis that hillslope discharge and soil loss could be affected by variation in the spatial correlation structure of coupled vegetation cover and soil patterns alone. The Limburg
Soil Erosion Model (LISEM) was parameterized and verified for a small catchment with discontinuous vegetation cover at Rambla Honda, SE Spain.
A disappearing biome ? Reconsidering land-cover change in the Brazilian savanna
Agricultural land use ; Brazil ; Environmental management ; Mato Grosso ; Plantcover ; Remote sensing ; Savanna ; Tropical zone ; Vegetation dynamics
with a critical review of Cerado land-cover change studies and the implications of evidence for vegetation regeneration, land-cover dynamism and land-use intensification, paying particular attention to spatial scale and research methods.
Land-cover changes of national nature reserves in China
Biodiversity ; China ; Ecosystem ; Habitat ; Index ; Nature conservation ; Nature reserve ; Plantcover
In this paper, 180 National Nature Reserves (NNRs) are selected. In terms of the ecosystem characteristics and their major protected object, all selected NNRs are classified into 7 types. A Positive and Negative Change Index of Land-cover (PNCIL
) was developed to analyze the land-cover change of each NNRs type from the late 1980s to 2005. The results show that the land-cover of all selected NNRs types have degradated to a certain degree except the forest ecosystem reserves with a decreasing rate
, but the rate of degradation alleviated gradually. The landscape pattern of land-cover in the core zones was more stable than that in the buffer zones and the experimental zones. Furthermore, the ecological diversity and patch connectivity of land-cover
in selected NNRs increased generally. In short, the land-cover of 180 selected NNRs in China had a beneficial change trend after NNRs established, especially between 1995 and 2005.
Natural vegetation of coal waste areas is sparse and patchy with low plantcover. More than 50 native plants species frequently occur there; they are better suited to recolonizing such sites than are exotic plants. - (DWG)
Albedo ; Climatology ; Conifer ; Cultivated plants ; Energy balance ; Local climate ; Minnesota ; Model ; Plantcover ; Regional climate ; Soil properties ; Spatial variation ; Surface temperature ; United States of America ; Vegetation
Albédo ; Bilan énergétique ; Climat local ; Climat régional ; Climatologie ; Conifère ; Couverture végétale ; Etats-Unis ; Minnesota ; Modèle ; Plante cultivée ; Propriétés du sol ; Température de surface ; Variation spatiale ; Végétation
are adequate to represent the effects of vegetation. Since the role of canopy cover and canopy height is well recognized in erosion models, the experimental programme was designed within a relatively narrow range of values for these parameters so
Gudalm Taluk in Nilgiri district of Tamil Nadu which was covered by tropical forest two centuries ago is now planted with tea, coffee and cinchona. - (PLK)
Stratified vegetation cover index : a new way to assess vegetation impact on soil erosion
China ; Concept ; Loess ; Plantcover ; Plateau ; Shaanxi ; Soil erosion ; Vegetation ; Vegetation index
This paper proposes a method to separately measure the cover of different vegetation strata, estimate their contribution to reducing soil loss, and then to integrate this into a single vegetation index called the stratified vegetation cover index
(Cs). The results in the Loess Plateau region of Shaanxi province show that Cs is more effective than projected vegetation cover for the assessment of soil erosion and also can overcome the disadvantages of vegetation indices such as NDVI. This means
that Cs is a good substitute for vegetation cover or cover-related vegetation indices in studies on the relationship between vegetation and soil erosion. The concept of Cs may help the local governors or forest department understand the importance
Land-cover effects on red soil rehabilitation in China : a meta-analysis
China ; Ecological rehabilitation ; Erosion control ; Man-environment relations ; Plantcover ; Red soil ; Soil ; Soil erosion ; Soil properties
Based on journal publications and a meta-analysis approach, this paper investigates the effects, and their spatiotemporal variations, of different land covers on red soil rehabilitation in China. Results indicate that all the land covers used in red
soil rehabilitation had been effective in improving degraded red soils but the degrees of effectiveness varied. Soil organic carbon was the most sensitive of the 3 major soil nutrients considered with regard to land-cover change during ecological
rehabilitation. Coniferous and broadleaf mixed forest was detected as the most effective land cover in red soil rehabilitation. Some spatiotemporal trends of land-cover effectiveness on red soil rehabilitation exist in a statistically significant sense
Impacts of grassland vegetation cover on the active-layer thermal regime, Northeast Qinghai-Tibet Plateau, China
China ; Climatic change ; Grassland ; Impact ; Mountain ; Periglacial features ; Permafrost ; Plantcover ; Plateau ; Qinghai ; Thermal regime ; Tibet
The study was conducted in the watershed of the Zuomaokong River in an alpine meadow over a three-year period. A high vegetation cover (93%) delayed thawing and freezing at a given depth relative to sites with lower covers (65%, 30% and 5%). Low
vegetation covers exhibited greater annual variability in soil temperatures, and may be more sensitive to changes in air temperature. Low vegetation covers are also linked to higher thermal diffusivity and thermal conductivity in the soils. The maintenance
of a high vegetation cover on alpine meadows reduces the impact of heat cycling on the permafrost, may minimise the impact of climate change and helps preserve the microenvironment of the soil.
Cover crops and their erosion-reducing effects during concentrated flow erosion
Agropédologie ; Belgique ; Erosion des sols ; Erosion hydrique ; Expérimentation ; Lutte contre l'érosion ; Plante cultivée ; Propriétés du sol ; Ruissellement ; Système racinaire
Agropedology ; Belgium ; Cultivated plants ; Erosion control ; Experimentation ; Rill wash ; Root system ; Soil erosion ; Soil properties ; Water erosion
Cover crops are a very effective erosion control and environmental conservation technique. When cover crops freeze at the beginning of the winter period, the above-ground biomass becomes less effective in protecting the soil from water erosion
, but roots can still play an important role in improving soil strength. Therefore, root density distribution with soil depth and the erosion-reducing effect of these cover crops during concentrated flow erosion were assessed by conducting root auger
. Fine-branched root systems (such as ryegrass and rye) are less vulnerable to frost. Ryegrass, rye, oats and white mustard are suitable cover crops to prevent concentrated flow erosion.