Rice, maize, corn, jute, mustard, potato and all sorts of vegetables are the main produce. There are a number of fruit orchards and horticulture gardens flank the river course. Even on the riverine isle and sandy river banks cultivation goes on during the post monsoon period from September till June. Banks of the channel and river course is dotted with villages under dense tree cover while paddy fields and grass lands border the wetland. The Oxbow Lake The oxbow lake of Purbasthali sprawls over an area 3.50 km2. in the post monsoon period of winter months. Beyond the lake, this river fed eco-system also forms a cluster of large and small islands comprise Purbasthali Gangetic Isle Complex. Formed by the meandering river Ganga, over last 40 years, the area has transformed into a closed loop, allowing emergence of the oxbow lake. This channel of water course in a length of about 10 kilometers feeds the oxbow lake with thin connectivity with the main river with shoals forming at the river mouth. The process of rapid and growing sedimentation threatens to cut off the channel in near future. Thus the present course of the main river shifts further eastward while the original bed holds the loop with stranded water. Remote sensing images of the wetland clearly establishes the differences of turbidity between the main river and the wetland which has sandy clay sediment and crystal clear waters because of sedimentation of suspended solid particles in the stagnant stretches. Geology On the basis of Geo-tectonic considerations, Purbasthali-Nabadwip region has been undergoing steady changes since time immemorial. River course has changed many times, due to geo-tectonic movements, forming small islands and oxbow lakes over last hundreds of years. The tectonic plates here are under constant collision resulted the changes in river course. A comparative study of the Survey of India topographic sheet published in 1973 with the remote sensing images of 1989-90&1992-93 coupled with observations from recent field visits, confirms the process of formation of this vast wetland besides some small but constant changes in topography occurring every year. Hydrology This wetland is still connected with the river Ganga(Bhagirathi) and its hydrology is mainly controlled by the river Ganga. During rainy season, when the river gets flooded, the water level within the wetland gets higher and some times the island within the wetland also gets flooded. Although, it has a huge open catchment