Thesis first page

Rangelands are highly degraded in many climatic regions of our country, Iran, due to mismanagement and unfavorable environmental condition such as prolonged and frequent droughts, hence structural and functionality of these vital ecosystems are degraded.

The shortage of water resources in our country has become a major challenge in recent years and evapotranspiration (ET) is major water losses  in agriculture land use. So, sustainable and optimum water resources management and plant water requirement require the accurate estimation of ET. Estimation of ET from remote sensing data is more appropriate than field methods, because spatial and temporal coverage of this method is very extend and time and cost are optimized.

Among the various desertification processes and vegetation degradation are the main processes in rangelands and it often starts with the reduction of vegetation cover.

Soil salinity is one of the major environmental problems that lead to crop yields failure and exacerbation of desertification in natural resources area.

Land use change is one of the most pervasive forms of ecosystem alteration and is commonly linked to other forms of environmental degradation including runoff increase, erosion, habitat and biodiversity loss, biogeochemical cycle alteration, ground water depletion, invasion of invasive species, the concentration increase of Co₂ and desertification. Studies have shown that landscapes with their natural condition are very little on the earth.

Sand dunes are one of the wind erosion^,s facies in sedimentary stage of this process which cover considerable extent of desert regions. Mobility is the most important characteristic sand dunes and important indicators of desertification processes that causes serious threats to agricultural lands, residentials and roads. Therefore, determining the development and movement of sand dunes are important goals in wind erosion studies in sedimentary areas.

The aim of this study was to investigate the status of dus storms in Kermanshah province, Iran, using climatic and remote sensing data.

Thesis first page

Desertification has been identified as an important global issue by United Nations in 1977 and nowadays its deleterious impacts on one billion people over 100 countries has proven as a huge eco-social and environmental calamity.