Water quality evaluation of typical Lake Wetland Parks around Dianchi Lake

School of Geography and Ecotourism, Southwest Forestry University, Kunming 650224, China

^* Corresponding author: ww0592@gmail.com

Abstract

Dianchi Lake is one of the key management points of China’s “three rivers and three lakes basins”, and the construction of wetland park plays an important role in purifying Dianchi lake water body and maintaining the health of lake ecosystem. Based on single factor evaluation method and three improved Nemerow pollution index methods, this study evaluates water quality of South Dianchi Wetland Park, Xihua Wetland Park and Laoyu River Wetland Park, with concentrations of total nitrogen (TN), total phosphorous (TP), chemical oxygen demand (COD), zinc (Zn), nickel (Ni), cadmium (Cd), chromium (Cr), lead (Pb) specifically measured and monitored. The results showed that: (1) the pollution levels of COD, TN, TP and Cr in the three wetland parks are relatively high. (2) based on single factor evaluation method and the improved Nemerow pollution index method, the evaluation grade of the water quality of the three wetland parks is inferior to Grade V. On the whole, the water pollution of Laoyu River Wetland Park is the most worrisome, and the water pollution of South Dianchi and Xihua Wetland Park is slightly better. (3) COD and TP are the main types of pollutants entering the lake in the basins where the three wetland parks are located. Therefore, immediate attention should be paid to the management of water quality state of Dianchi Lake, and the treatment of urban, agricultural non-point source and some uncollected point source pollution should be further strengthened.