标题：Physico-chemical characterizations of surface water and underlying sediments and limnological status of Beeshazari Lake, a Ramsar site at Chitwan, Nepal
期刊名称：International Research Journal of Environmental Sciences
电子版ISSN：2319-1414
出版年度：2019
卷号：8
期号：4
页码：28-36
语种：English
出版社：International Science Community Association
摘要：Beeshazari Lake, a Ramsar site at Chitwan in central Nepal of international concern and importance, provides suitable habitats for many globally threatened or endangered flora and fauna but the lake of proper monitoring and management practices have caused the severe degradation of the lake. In the present study, physico-chemical characterizations of surface water and bottom sediments were made to assess the limnological status of the lake. The study was conducted for a period of three consecutive years (2016-2018). The mean levels of temperature, transparency, pH, DO, NO3--N, TN, TP, GPP and Fe in the lake water were found to be 23.7 0C, 1.1 m, 6.5, 4.1 mg/L, 217.9 µg/L, 1386.4 µg/L, 208.0 µg/L, 36.4 g C/m2/yr and 0.5 mg/L respectively. The lake water was found unfavorable to aquatic animals due to low pH and transparency, depleted DO level and high levels of TN and TP. Similarly, the mean levels of temperature, pH, TN, available P, OM and Fe in the underlying sediments of the lake were recorded as 24.0 0C, 6.2, 3.7 g/Kg, 85.2 mg/Kg, 72.0 g/Kg and 29.0 mg/g respectively. The elevated levels of OM, TN and available P in the lake sediments are potential nutrient sources to the surface water. Moreover, the eutrophic nature of the lake was by transparency and nitrogen criteria and hyper-eutrophic by phosphorus criteria. Correlation analysis revealed positive as well as negative correlations among some of the water quality parameters as well as sediment parameters. From the present study, we conclude that Beeshazari Lake is in urgent need of effective planning and policies, strategies and management practices for its conservation in the long run so that the present limnological status of the lake could be improved.
