A recent study by Nagaland University has raised serious environmental concerns over the deteriorating health of Loktak Lake — India’s largest freshwater lake and a designated Ramsar Site — warning that unchecked human activities are endangering its fragile ecosystem.

The research, led by Dr. Eliza Khwairakpam, Assistant Professor in the Department of Environmental Science, revealed that extensive land use changes — including agriculture, human settlements, and shifting cultivation — are directly degrading the water quality of rivers feeding into the lake. This, in turn, threatens the biodiversity and livelihoods of local communities dependent on the lake.

Located in Manipur’s Bishnupur district, Loktak Lake supports over 130 plant species and more than 400 animal species. It is also vital for hydropower, fisheries, transport, and tourism. Despite its international recognition under the Ramsar Convention, the lake has been placed on the Montreux Record — a global list of wetlands facing serious ecological damage.

Field sampling was carried out across nine rivers — Khuga, Western, Nambul, Imphal, Kongba, Iril, Thoubal, Heirok, and Sekmai — that drain into Loktak. By comparing land use patterns with water quality indicators such as dissolved oxygen (DO) and biological oxygen demand (BOD), researchers found clear evidence linking upstream land activities to downstream water pollution.

“The study confirms that land use decisions across villages and forest areas are directly affecting river and lake water quality. Community-based land management and strict control over agricultural runoff and waste discharge are crucial for restoring Loktak Lake,” said Dr. Khwairakpam.

According to the study, the Nambul River was identified as the most polluted, with low oxygen levels and high organic contamination, primarily due to agricultural and settlement pressures. The Khuga River followed, showing significant degradation linked to extensive shifting (Jhum) cultivation. Conversely, rivers like Iril and Thoubal, which flow through denser forest zones, exhibited better water quality — underscoring the protective role of natural vegetation.

The research, jointly supported by Nagaland University, IIT Delhi, and the Manipur Forest Department, emphasized that sustainable land management, regulated Jhum cycles, and eco-friendly farming practices are key to safeguarding the lake — which also houses the Keibul Lamjao National Park, the world’s only floating national park and the habitat of the endangered Sangai deer.

Commending the study, Nagaland University Vice Chancellor Prof. Jagadish K. Patnaik said the findings underscore the urgent need to address the environmental challenges arising from agricultural runoff and human encroachment. “Nagaland University remains committed to advancing research-driven solutions that protect natural ecosystems and sustain local livelihoods,” he added.