Monitoring and Management of Asan Reservoir Wetland and Environs using High Resolution Satellite data

Abstract

Asan Conservation Reserve (ACR) is one of 42 wetlands of International Importance under Ramsar convention and lies in the Central Asian-Indian Flyway and East Asian-Australian Flyway of migratory birds in Doon Valley in Western Himalaya. The valley-landscape is unique and complex with a mix of land use/land cover such as forests, rivers, urban as well agricultural landscape in the Himalayan Biodiversity Hotspot region with high seasonality, water flow and area fluctuations, vegetation physiognomy and phenology, tourism, etc. Even though the migratory and resident birds occupy wetland for most of their stay time, however, the role of the adjacent land use practices play a very important role in food supply chain. We used six-time high resolution time-series temporal (summer and winter) satellite images of LISS IV sensor for the years 2004, 2013 and 2016 to understand the wetland dynamics and its unique ecological significance in terms of conservation and management of ACR for avifauna, specially migratory birds and aquatic vegetation. The area analysis of wetland and its environs between 2004 to 2016 indicates decreasing trend of about 3% (0.14 km 2 ), 4% (0.65 km 2 ), 1% (0.18 km 2 ) and 15% (2.02 km 2 ) in wetland area, riverine scrub, mango orchards and agriculture land, respectively. An increasing trend has been observed by 4% (0.348 km 2 ), 1% (0.067 km 2 ), 3% (0.18 km 2 ), 4% (0.2 km 2 ) and 5% (0.35 km 2 ) in settlement area, siltation, total forest cover, water body and wet riverbed, respectively. However, dry riverbed has remained almost unchanged occupying about 17%. The water and vegetation ratio is nearly ideal in the ratio of 60:40, and if needed, desiltation may be carried after mid-March.