ECOLOGICAL HEALTH ASSESSMENT OF KANJLI LAKE- A RAMASAR SITE

Abstract

Increasing anthropogenic impacts on water resources has led increased concern about the health of water bodies. Assessment of health with respect to the ecological quality of lakes and streams is an important aspect to determine the effects of the different stressors, their level and how these stresses accumulates. Healthy water bodies exhibit ecological integrity, representing a natural or undisturbed state. Ecological integrity is a combination of three components: chemical integrity, physical integrity, and biological integrity. When one or more of these components is degraded, the health of the water body will be affected and, in most cases, the aquatic life living there will reflect the degradation. The identification of water quality degradation requires appropriate monitoring tools. Such tools help us detect and characterize the cause and source of chemical, physical and biological impairment. The ecological health of a lake can be expressed in terms of water quality, Trophic State and Biodiversity Riparian Vegetation and macro invertebrate popularly in it. The present work deals with assessment of the ecological health status of Kanjli Lake, Punjab, India through various parameters of water quality. Punjab has three Ramsar sites viz. Harike, Kanjli and Ropar. Kanjli provide habitat to diverse flora and fauna including some rare and threatened plant and animal species. Major threats to its ecosystem are from siltation, agriculture runoff, water pollution and infestation of weeds. Hence evaluating the current health status of the lake will help the regulatory authorities to conserve and restore the lake to its natural state. Ecological Health status of Kanjli was analyzed based on Water Quality Index (WQI), Trophic State Index (TSI), Simpson Diversity Index (SDI) and Macro Invertebrate Index or Biotic Index (BI) value for the Kanjli Lake. NSFWQI and CCME WQI shows that water quality was good in winter which turned into medium or fair and not suitable for drinking purpose. WAIM WQI result also estimated the poor quality of water in summer. Productivity of lake was calculated in terms of trophic state and it was found in mesotrophic state where TSI was estimated in the range of 60-70 for all the sampling points during both the seasons. Based on Florida TSI, lake was found to be Nitrogen limited where it support some growth of unwanted aquatic flora. Riparian vegetation analysis was done and index value for both Simpson and Shannon-Weiner Index represented good diversity around lake. iv | P a g e Apart from analysis of physical parameters macro invertebrate index i.e. HKHBIOS, SIGNAL, Shannon-Weiner Index etc. were evaluated and lake water was found to be polluted and this has been confirmed by the presence of tolerant and very tolerant macro invertebrate species. The overall ecological health or EQI has been calculated based on NSFWQI, TSI and SDI and it was found as 2.3 which lies in medium health with ranges 2-3. It means that the water is not suitable for drinking purpose and due to considerable productivity of the lake, it supports the growth of aquatic plants. Hence, the nutrient effect is objectionable in the lake for which conservation measures are recommended. It has been observed that water quality of the Kanjli is not good and the presence of tolerant species of macro invertebrate community showed that lake is getting pollution in significant amount which is deteriorating the health to worse. These adverse factors needs to be dealt with various management strategies which will help to improve the ecological health of Kanjli Lake.