Authors: JIANG Yan, PENG Qi-dong, LUO Hui-huang, MA Wei (China Institute of Water Resources and Hydropower Research, Beijing 100038, China)

Abstract: Based on survey data of 82 monitoring stations from 1986 to 2005, the spatial and temporal variation of water quality in the Huaihe River basin were investigated and analyzed to provide scientific basis for water pollution control, water environment protection and ecological restoration. The time series analysis method and Mann-Kendall testing method were adopted to analyze the water pollution status and change trend over the past twenty years. The results show that four main factors influence the change of water quality, including river pollution load, upstream inflow, dam and gate operation, and climatic condition. The water quality of the Huaihe River exhibits a tendency of gradually deteriorated before 1995 and gradual improved after 1995. The change of dissolved oxygen (DO) is affected by water temperature varying in a year, with higher concentration in winter than that in summer. The chemical oxygen demand (COD Mn) is affected by operation of dam (gate) and interval inflow simultaneously which is lower in flood season than that in non-flood season. It indicates that significant effects of water pollution control have been obtained throughout the whole watershed in late 1990s when it was a relative high flow period for this area. However, tendency analysis shows that significant deterioration of water quality was present on north tributaries of the Huaihe River basin. Following the increase of pollutant discharge and river pollution load after 2000 water quality pollution in Huaihe River basin is still serious.

Key words: Huaihe River basin, water pollution, time series analysis, Mann-Kendall test, dissolved oxygen, chemical oxygen demand, ammonia nitrogen

Published in: Journal of Hydraulic Engineering, Vol. 42, No. 11, 2011
Article ID: 0559-9350 (2011) 11-1283-06