Use of LANDSAT ETM + Data for Detection of Prosopis juliflora in Irrigated Zones

Abstract

Prosopis juliflora (PJ) can be used as a relevant indicator for integrated management of irrigated saline soil in arid zones. Remotely Sensed Landsat Enhanced Thematic Mapper Plus (ETM+) dataset was used for detection and delineation of areas under PJ. The vegetation densities were classified using normalized difference vegetation index (NDVI) whereas soil moisture levels were estimated based on distribution of soil wetness index (SWI). The classified NDVI map was combined with classified SWI map for detection of PJ. It is considered that the available water in the soil is one of the determinants of plant species and densities. The field checks show that the soil under PJ is drier than the irrigated soils mainly in dry season. Therefore, the dense and medium vegetation distributed on drier soils are considered as PJ. About 16.17% of reviewed area is covered by dense and 11.29% by sparse PJ. Overall accuracy of the analyses is about 87%. The dense PJ is classified more precisely than the sparse. The methodology formulated in the study can be used as a rapid assessment tool prior to planning and monitoring the saline lands of arid zones.