National Wetland Atlas of India

The National Wetland Atlas 2011 has used confusing and inappropriate classifications. Many man-made wetlands have been treated as naturally occurring, tanks have become lakes, and a large number of ponds have become nondescript entities. The number of inland wetlands estimated is far less when compared to other known sources of data, creating reasonable doubt on the reliability of the exercise. This article emphasises the need for releasing the complete geo-coordinates and areal data sets, and undertaking accurate assessments of the numbers and water spreads of tanks and ponds.

The National Wetland Atlas 20111 (hereafter the Atlas) had the objective to map all types of wetlands and to become a national database by bringing out state-wise detailed publications. The Atlas, apart from producing the maps, estimated the area, vegetation and turbidity levels of wetlands. The Atlas project used satellite images from the Linear Imaging Self-scanning Sensors-III (LISS-III) with a resolution of 23 metres and thereby able to view water bodies up to a size of 529 square metres. The project was led by the Space Applications Centre (SAC) of the Indian Space Research Organisation (ISRO), and 25 other specialist institutions undertook the project in their respective states. Though the Atlas is an earnest effort to use the advancements in earth observation technologies such as the remote sensing and geographic information system (GIS) tools, it is riddled with definitional problems, inconsistency of method and a poor understanding of Indian wetlands. The review highlights some of these issues affecting “man-made tanks and ponds”, which constitute the largest chunk of the Indian wetlands.