Assessment of water quality and biomass productivity of the tropical floating meadows of Keibul Lamjao National Park, Manipur.

Abstract

Wetlands represent the aquatic edge of many terrestrial plants and animals; they also represent the terrestrial edge of many aquatic plants and animals. They are fast becoming a focus for research, management, and restoration activities because of high biodiversity, productivity and for their well-documented ecosystem service values. Wetlands with floating meadows largely occur in temperate and tropical freshwater wetlands throughout the world. In India, they occur in floodplains of Northeast India, particularly in Loktak Lake of Manipur valley. The Keibul Lamjao National Park (KLNP) located in the southern part of the Loktak Lake, with its characteristic floating meadows is the only natural habitat of the Manipur’s brow antlered deer Rucervus eldii eldii locally called the Sangai which is perhaps the most threatened deer species in India. These meadows, locally called phumdis, are a heterogeneous mass of soil, vegetation and organic matter in various stages of decomposition which occur in different thickness ranging from a few centimeters to about 2.5 m. With the construction of Ithai Barrage on Imphal River, the floating meadows, which used to settle during the lean season and get replenished with soil and nourishment, are now continuously floating, resulting in their thinning and thereby threatening the existence of Sangai. The floating meadows also provide a biological sink for the key nutrients and govern the water and nutrient dynamics of this Lake ecosystem. The need to study the ecology of the floating meadows and the role it plays is therefore immensely important for the conservation of the endangered Sangai. The major objectives of the proposed study were to; (a) examine the ecological conditions of the KLNP in terms of water quality and nutrient status (b) derive the species richness and plant community composition of the Park and, (c) to quantify the pattern of biomass production by the floating meadows and its utilization by Sangai and Hog deer