Variation of low water level of Dongting Lake in recent 30 years, China

---

Tuesday 30 june 2015

17:51 - 17:54h at North America (level 0)

Themes: (T) Extreme events, natural variability and climate change, (ST) Hydrological extremes: floods and droughts, Poster pitches

Parallel session: Poster pitches: 7I. Extreme - Flood Drought

---

Dongting Lake is located in the northern part of Hunan province in China, and connected with the middle Yangtze River through three outfalls. Its evolution has always played an important role not only in the flood control, but also the ecological environment and water resource in this region. As one of the key factors influencing the evolution, the low water level of Dongting Lake has varied because of the human activities in the last few decades. These changes will not only bring about adverse effects on eco-environment in this region, but also change the relationship between Dongting Lake and the Yangtze River. Especially after experiencing twice severe droughts in 2006 and 2009, the low water level in Dongting Lake becomes a hot issue and key problem. In this article, a series of daily water level data of the lake since 1980' was employed to analyze its varying characteristics. The result shows that the lowest low water level each year and its appearance date has slightly changed in recent 30 years, while the mean water level in dry season gradually declined. Especially since the impoundment of Three Gorges Reservoir, the water level of Dongting Lake in September and October has markedly declined, which means that the duration of the dry season has been extended.