MAPPING AND MONITORING PLANNED DEVELOPMENT OF VEGETATION COVER IN DESERT AREA USING TEMPORAL REMOTE SENSING DATA

摘要

Remote sensing data provides an ability to effectively map and monitor dynamic phenomena and resultant changes. This study uses Landsat TM temporal imagery of 1989, 1998 and 2009 to map and assess the increase in the vegetated area in a part of desert under a planned national level strategy. This strategy is aimed to increase the vegetated land in the desert and to control salinity and reclaim water logged land in the upper areas. The water diverted from rivers and from the water logged areas is pumped out to properly layout canal and then spread out to the desert area through a number of drains. To assess the change in vegetation cover over a period of last two decade (year 1989-2009), all of the images were classified to two main classes' namely planned vegetated areas (for cropping purpose) and emerging vegetation areas (just green area with any type of vegetation). The classification accuracy for both the classes was 90%, 86%, and 85% for 1989, 1998 and 2009 images, respectively. After the classification, both the classes were extracted and analyzed for the changes during this time period. The change analysis show that since 1989 to 2009, there is about 5% increase in the planned vegetated area (cropland) and a very huge increase of about 300 % in the emerging vegetation area. It is expected that in future this emerging vegetated area will be used for agriculture purpose and the further green desert areas drive will continue. The results clearly indicate the usefulness of RS data for monitoring and mapping dynamic phenomena spread over wide areas which otherwise is very difficult.