Loktak Lake is the largest freshwater lake in Northeast India and is famous for the phumdis (heterogeneous mass of vegetation, soil and organic matter at various stages of decomposition) floating over it. The lake is located at Moirang in Manipur state, India. The etymology of Loktak is Lok = “stream” and tak = “the end”. The largest of all the phumdis covers an area of 40 km2 (15 sq mi) and is situated on the southeastern shore of the lake. Located on this phumdi, Keibul Lamjao National Park is the only floating national park in the world. The park is the last natural refuge of the endangered Sangai (state animal), Rucervus eldii eldii or Manipur brown-antlered deer (Cervus eldi eldi), one of three subspecies of Eld’s Deer.
This ancient lake plays an important role in the economy of Manipur. It serves as a source of water for hydropower generation, irrigation and drinking water supply. The lake is also a source of livelihood for the rural fishermen who live in the surrounding areas and on phumdis, also known as “phumshongs”.
A rich biodiversity with habitat heterogeneity has been recorded during a scientific survey carried out between January 2000 and December 2002 in different habitat patches of the lake. The lake’s rich biological diversity comprises 233 species of aquatic macrophytes of emergent, submergent, free-floating and rooted floating leaf types.