Accurate estimation of green aboveground biomass in arid and semiarid grassland is essential for a variety of studies, such as sustainable grassland management, fire risk assessment, climate change, and environmental degradation. A great need exists for the establishment of robust method for estimating green aboveground biomass in arid and semiarid grassland due to the influences of soil backgr...

One of the characteristics in Iranian Model of Desertification Potential Assessment (IMDPA) is vegetation. Sincevegetation is very important factor in the degradation of land, so some indices were determined for this item in order toevaluate desertification potential of arid, semi arid and arid sub humid areas of Iran. The indices included vegetationcondition, exploit and revegetation. To calib...

This paper reports a practical application of digitally enhanced Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) data coupled with principal component analysis (PCA) and spectral angle mapping (SAM) techniques to assess changes in vegetation and land condition within the U.S. Army installation at Fort Bliss, Texas. Fort Bliss is located in a semi-arid desert environment wh...

Afghanistan is a very mountainous country. It offers a big variety of ecological conditions, this means a big variety of vegetation types is covering land surface. These vegetation types are consisting of a high biodiversity, since the floristic influence from various neighbour regions is a considerable factor in floristic and vegetation pattern. On the other hand, Afghanistan is a very dry cou...

The evaluation of vegetation covers using conventional methods is difficult over arid areas due to several reasons such as lack of the suitable roads to these regions. Moreover, this task is time-consuming. For these reasons, remote sensing has been considered as an economic alternative for conventional field work. In this study, the feasibility of using IRS images in vegetation cover evaluatio...

We evaluated the response of the Earth land biomes to drought by correlating a drought index with three global indicators of vegetation activity and growth: vegetation indices from satellite imagery, tree-ring growth series, and Aboveground Net Primary Production (ANPP) records. Arid and humid biomes are both affected by drought, and we suggest that the persistence of the water deficit (i.e., t...

Arid ecosystems are liable to undergo sudden discontinuous transitions from a vegetated to a desert state as a result of human pressure and climate change. A predictive framework about the conditions under which such transitions occur is lacking. Here, we derive and analyze a general model describing the spatial dynamics of vegetation in arid ecosystems considering local facilitation as an esse...

The rapid expansion of deserts in recent decades as a result of human actions combined with climatic changes has highlighted the necessity to understand biological processes in arid environments. Whereas physical processes and the biology of flora and fauna have been relatively well studied in marginally used arid areas, knowledge of desert soil micro-organisms remains fragmentary. The objectiv...

Arid grasslands are used worldwide for grazing by domestic livestock, generating debate about how this pastoral enterprise may influence native desert biota. One approach to resolving this question is to experimentally reduce livestock numbers and measure the effects. However, a key challenge in doing this is that historical grazing impacts are likely to be cumulative and may therefore confound...

The objective of this research was to identify the vegetation-soil relationships in Nodushan arid rangelands of Yazd. 5 sites were selected for measuring the cover of plant species and soil attributes. Soil samples were taken in 0-10 and 10-80 cm layers. The species studied were Salsola tomentosa, Salsola arbuscula, Peganum harmala, Zygophylum eurypterum and Eurotia ceratoides. Canonical corres...