metric (mapping evapotranspiration at high resolution with internalized calibration) is known as an appropriate surface energy balance model for the estimation of the spatial distribution of evapotranspiration (et) in semi-arid regions. based on lysimeter measurements, metric has shown et estimates of 10% on a sub-field scale on a daily basis. there is a need to identify how the model is sensit...

In order to promote an increased ability to compare results from different studies, a standard protocol for controlled trampling experiments is suggested. The procedure will provide information on both damage to vegetation in response to short-duration trampling and subsequent recovery over a one-year period. Changes in vegetation cover, vegetation height, bare ground cover, and the cover of in...

Recent theoretical studies have shown that spatial redistribution of surface water may explain the occurrence of patterns of alternating vegetated and degraded patches in semiarid grasslands. These results implied, however, that spatial redistribution processes cannot explain the collapse of production on coarser scales observed in these systems. We present a spatially explicit vegetation model...

Water scarcity is one of the factors limiting plant growth and development. More than onethird of the global terrestrial ecosystems is located in arid and semi-arid regions. The mostimportant limiting factor for plant growth is water shortage. Drought could significantlychange the natural vegetation cover. Rainfall reduction in Iraq, Turkey and Syria hasreduced vegetation cover so that dust sto...

Deforestation in the tropical Andes is affecting ecological conditions of streams, and determination of how much forest should be retained is a pressing task for conservation, restoration and management strategies. We calculated and analyzed eight benthic metrics (structural, compositional and water quality indices) and a physical-chemical composite index with gradients of vegetation cover to a...

this study was carried out to investigate the effective environmental factors in the distribution of vegetation in zirkouh rangelands of qaen. after delimitation of the study area, sampling of soil and vegetation were performed using randomized- systematic method. vegetation cover was recorded by using braun-blanquet combined abundance-cover scale in each sample. within each sample, one profile...

Vegetation structure and density affect the dynamics of snow accumulation and ablation. Vegetation also affects our ability to estimate snow-covered area accurately from satellite-based sensors. The objective of this case study is to demonstrate how the angular pattern of reflectance from vegetation over snow can provide information on forest cover density. Imagery from the Multi-angle Imaging ...

Many algorithms have been developed for the remote estimation of vegetation fraction in terms of combinations of spectral bands, derivatives of reflectance spectra, neural networks, inversion of radiative transfer models, and several multi-spectral statistical approaches. The most widespread type of algorithm used is the mathematical combination of visible and near-infrared reflectance, in the ...