Imphal, August 27 2009: The characteristic feature of the Loktak Lake in Bishnupur district of Manipur is the presence of 'floating islands' covered with vegetation, locally known as 'phumdis'.

These floating islands, occurring in all sizes and thicknesses, are heterogeneous mass of soil, vegetation and organic matter at various stages of decomposition.

They float on the Loktak Lake with about one-fifth of their thickness above and four-fifth under the water surface.

The core of phumdis is composed of detritus which is black in colour and highly spongy.

The phumdis play an important role in the ecological processes and functions of the lake.

They provide a biological sink to the key nutrients and govern the water quality and nutrient dynamics of the lake.

They harbour several plant species and support a rich biodiversity.

Several plant species of economic and ecological importance take part in the formation of phumdis.

Keibul Lamjao National Park (KLNP) is the largest contiguous mass of phumdis providing natural habitat for the highly endangered ungulate species, Cervus eldi eldi, locally called Sangai deer.

There has been great concern during the last few decades about the proliferation of phumdis in the main lake and reduction in the thickness of phumdis in the KLNP.

A lot of controversy has been generated by different stakeholders in the absence of reliable data.

This has created more confusion and no sound solution seems to be available to manage the phumdis.

The University of Manipur has undertaken several studies on the lake including the ecological aspects of phumdis.

Several other state government departments have tried to utilize phumdis for different purposes.

Loktak Development Authority (LDA) and Wetlands International - South Asia (WISA) under the project on Sustainable Development and Water Resources Management of Loktak Lake (SDWRML) have collected a lot of data on phumdis of Loktak.

Realizing its prolific growth and its several impacts on the lake ecosystem, a workshop has been organized inviting all concerned stakeholders, scientists, policy planners, NGOs and community groups to deliberate on the issues relating to the phumdis management, which discussed about the ecological relationship of phumdis in the Loktak lake, lake hydrology and phumdis, biodiversity of phumdis, phumdis and fisheries development, phumdis and communities and economic utilization of phumdis.

The profuse growth of phumdis in the Loktak Lake has reached an alarming situation, and this has been a matter of great concern to the communities living in and around the lake.

The enormous growth of phumdis is also impacting the lake ecosystem processes and functions and recent investigations indicated that if unabated growth of phumdis continues, it may affect the whole lake, as some negative effects of phumdis have already been found in the KLNP area.

Realizing this, SDWRML project carried out an extensive consultation process through organizing community meetings at nine locations which broadly represent the different sectors of the lake, and the following issues emerged during these meetings regarding the causes of proliferation of phumdis, its impacts and suggested control measures.

The causes for the proliferation of phumdis are regarded to be the stagnation of water due to construction of Ithai barrage, pollution from the towns and villages brought to the lake through Nambul, Moirang, Merakhong and Thongjaorok rivers which fall into the Loktak lake and 'athaphum fishing' - a traditional method of fishing, wherein circular enclosures are made in the lake using pieces of thick phumdis.

The impacts of the phumdis are restriction of movement inside the lake, water logging in peripheral areas, health hazard due to deterioration in water quality, decline in fisheries and availability of vegetables.

The control measures suggested are periodic opening of the Ithai barrage, deepening of the channels associated with the Loktak lake, restriction of 'athaphum fishing', cutting and piling of phumdis to form bundhs and release of fish like grass carps which feeds on the phumdis.

The communities in most of the meetings proposed joint effort of LDA and the communities living in and around the Loktak lake to remove phumdis.

It was also suggested that strategies should be developed for long term management of the phumdis in consultation with communities living in and around the Loktak.

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