Impacts of human activities on the hydrology of Baiyangdian Lake, China

Baiyangdian Lake is the biggest natural freshwater wetland in North China Plain. It provides important ecosystem services such as water regulation and supply, reed production and biodiversity protection. Baiyangdian Lake, however, was threatened by lack of freshwater in recent decades. In this paper, the hydrological changes of the lake were quantified using historical data of water level and groundwater table, and satellite images. In addition, the relationship between water level and socioeconomic development of the basin was investigated. The result revealed a significant decreasing trend of water level in the lake. Water level and groundwater table of Baiyangdian Lake decreased rapidly, caused by the great increase of water withdrawal and consumption due to socioeconomic development in the basin. In particular, population growth and the expansion of irrigated agriculture were two major contributors to the decline of water level and groundwater table. While precipitation was positively correlated with water level, it has less impact on water level and groundwater table than human activities. The diversion of water to the lake raised the water level temporarily and had significant benefits on the wetland ecosystem. The best way to solve ecological problems of Baiyangdian Lake, however, is to control the growth of population, adjust the industrial structure, control land use conversion and improve water use efficiency at the basin scale.