Abstract

Wetlands are an essential part of human civilization meeting many crucial needs for life on earth such as drinking water, energy, biodiversity, recreation, and climate stabilizers. Burgeoning populations, intensified human activity, unplanned development, absence of management structures, and lack of awareness about the vital role played by these ecosystems are the important causes that have contributed to their decline and loss. Identifying, delineating, and mapping of wetlands on a temporal scale provide an opportunity to monitor the changes, which is important for natural resource management and planning activities. Temporal RS data coupled with spatial analysis helps in monitoring the status and extent of spatial features. Extracting spatial features such as wetlands (which include lakes, ponds, tanks, marshy areas, etc.) from multi-sensor multi-resolution images acquired from the earth observation satellites helps in monitoring their status including spatial extent, physical, chemical, and ecological aspects. In this work an attempt has been made to evaluate the performance of five image fusion techniques on mutli-sensor multi-resolution remote sensing data. Finally, the optimal fused images were used to carry out the temporal analyses of wetlands in Greater Bangalore using pattern classifier, which indicated decline of 60.83% of wetlands area during 1973-2007 due to increase in built-up area. There were 159 wetlands spread in an area of 2003 ha in 1973 which declined to 93 (both small and medium size) with an area of 918 ha.

Keywords: Multi-resolution, multi-sensor, image fusion, pattern classifier, wetlands.