Operational Monitoring of Vegetative Cover by Remote Sensing in Semi-arid Lands of Iran

SUMMARY Operational monitoring of vegetative cover by remote sensing currently involves the utilisation of vegetation indices. Vegetation indices are widely used for assessing and monitoring ecological variables such as vegetation cover, above-ground biomass and leaf area index. This study reviewed and evaluated different vegetation indices for estimating vegetation cover in rangelands in Center of Iran. All vegetation indices were calculated from ASTER (Advanced Spaceborn Thermal Emission and Reflection Radiometer) image data and compared with vegetation cover estimates at monitoring points made during field assessments. Relationships between various vegetation indices and vegetation cover were compared using simple linear regression. NDVI vegetation index evaluated, using high infrared and low red ASTER bands, consistently showed significant relationships with vegetation cover. Estimation of vegetation cover whit NDVI vegetation index was more accurate and total perennial and ephemeral plant cover was best predicted within rangeland systems. These results provide a strong foundation for use of vegetation indices as an adjunct to field methods for assessing vegetation cover in northern Center Iran.