78
Tecnología y Ciencias del Agua
, vol. VIII, núm. 2, marzo-abril de 2017, pp. 77-91
Mao
et al.
,
The runoff variation characteristics of Dongting Lake in China
•
ISSN 2007-2422
Over view of the study area
Located in the northeast of Hunan Province
and on the south bank of Jingjiang River, a
stem stream of Yangtze River, Dongting Lake
lies across Hunan and Hubei Province and
has a close relationship with middle reaches
of Yangtze River. Dongting Lake is the second
largest freshwater lake in China, which has
surface area 2 625 km
2
and plays an important
role in flood water storage. The inflow contains
four big rivers of Hunan (Xiang River, Zi River,
Yuan River, Li River), three bayous of Yangtze
River (Songzikou, Ouchikou, Taipingkou) and
several small rivers (Miluo River, Xingqiang
River, etc.). Those flows inject into Dongting
Lake, stored, and then discharges into Yangtze
River at Chenglingji. The details of the sche-
matic diagram are presented in (figure 1).
Temporal distribution of precipitation is un-
even in Dongting Lake Region.The wet season
which from April to September provides about
65% of annual precipitation, which increases
the risk for regional flood disaster. Because of
the unevenness of inter-annual rainfall, drought
and flood possibility is very high, what’s worse,
even in the flood years, the extreme weather like
drought would possibly happen in Dongting
Lake Region. Flood and drought disasters are
the most severe disasters in Dongting Lake
Region. According to the statistics, the annual
average direct economic loss caused by flood
is up to 1.858 billion in agriculture (Li, Zheng,
& Gao, 2000). During last 60 years, the most
terrible floods occurred in 1954, 1996 and 1998
(Mao, 1998; Mao, 2000) while in 1960, 1963 and
1968 occurred serious droughts. During time
period from1970 to 2005, the extreme droughts
occurred 5 times.1998 and 2002 are extreme
flood year and 1969, 1973, 1980, 1993, 1995 and
1999 flood years (Zhang, Zhang, & Li, 2009).
In 21 century, the drought situation is getting
worse; 2003, 2006 and 2011 were sustained
drought years in Dongting Lake region. Water
shortage threatened inhabitants’ water security
and water supply in agriculture and industry
around the lake, which has caused great atten-
tion from scholars. Researchers focus on the
analysis of hydrology and sediment transport
process, evaporation, precipitation, climate etc.
The main aim of this study is an investigation
of the relationship between runoff (three bayous
Figure 1. Schematic diagram of study area.
