Abstract ID
biodiv53
Type
Oral
Theme
biodiv
Full title
Improving the ecosystem services of floodplains in the middle course of the Yangtze River, China
Abstract text
Poyang Lake, located N28°22 to 29°45, E115°47 to 116°45, with the area of 3,914 km2, is the large
freshwater lake in China and also a major lake in the Yangtze Basin contributing 14.7 billion m3 of freshwater
annually from the lake toward the river. The water level significantly fluctuates in a year with respect to the
floodplain. However, the upstream Three Gorge Dam construction may have led to the lowest record stage of
7.29 m at the end of 2007. The low water level lasted for all of 2008. Arguments on the necessity of building
levees to maintain the water level were raised after that. Poyang Lake, connecting with the Yangtze River, has
important ecosystem services, including flooding control, water treatment, and biodiversity. Besides the
disturbance from the Three Gorge Dams on the water level, it faces increased environmental problems such as
pollution from agriculture and urbanization and soil losses. The paper discusses how the services change with
different scenarios. We think that the levees will maintain a stable water level while they may cut off the
connection between the Poyang Lake and the other floodplains. Most of the wetlands with pulsing water levels
will be replaced with permanently inundated wetlands. Thus, the ecosystem services will be changed
significantly, especially the improvement of water quality. The capacity of the floodplains and reservoirs
upstream of Poyang Lake is estimated to determine whether they can support the lake during drought periods.
The uplands around Poyang Lake are important for soil loss control and water supply. We suggest that
development of the upland area should be controlled and restored to forests and woodlands. Based on the
functions of floodplains, keeping as much of the area as possible as healthy wetlands may be a better solution
than the levee system.
Submission date
2009-10-25
Keywords
ecosystem services, Three Gorges Dam, floodplains, Yangtze River
Will be submitting paper?
Yes