Geoscience Reference
In-Depth Information
Table 24.2
Assessment of the principal ecosystem services of Poyang Lake Wetlands.
Ecosystem
Service
Impact (external
and internal)
Current Status
Direction of changes
Drivers of change
Supporting
Migratory bird
species
>
400 000 birds
annually, including 19
threatened species,
visit and use the lake.
Improving
Establishment of 14 nature
reserves
Habitat destruction in
middle reaches of
Yangtze River
Global
Other species
Habitat for 114 species
of fish, key habitat
for finless porpoise
20 fish species extinct;
Yangtze dolphin
critically endangered
Finless porpoise
threatened
Dams upstream
Over-fishing
Habitat destruction
Deteriorating aquatic
environment in the
whole river
Global and
regional
Primary
production
5.6 x 10
6
tbiomass
annually
Declining
Wetland reclamation
Local
Hydrological
cycle
15% of water outflow
to Yangtze River.
Groundwater of the
Poyang Lake basin
maintained
Hydrological
buffer/flood
retention function
declining
Wetland reclamation leads
to decline in water
retention capacity
Regional
Nutrient cycle
and soil
formation
Soil and nutrients from
the lake basin
trapped
Declining
Wetland reclamation
Lake basin
Regulating
Flood
mitigation
>
1466 km
2
wetland
converted to farmland
Reduction of 48-53% of
the flow from its
tributary rivers
Flood retention
capacity decreased by
30%
Regional and
local
Carbon sink
Annually fixes 300 000-
480 000 t of organic
carbon, with total
storage of 32 x 10
6
t
Biomass decreased by
30%
5-7.5 x 10
6
toforganic
carbon loss.
Wetland reclamation
Global
Provisioning
Water
On average 400 x 10
6
m
3
d
−1
of fresh water
every day
Potable water resources
decreased by 36%
Water pollution from
industries, sewerage and
agriculture /aquaculture
Regional and
local
Fish for food
Fishery of
>
600 000 t
annually
Aquaculture
production been
increased, but natural
stocks decreased
Overfishing;
Destruction of spawning
sites
Local
Building
materials
Extraction of 48 x 10
6
t
yr
−1
of sand
Sand resources
depleting
Over-exploitation
Local impact on
wetland
hydrology in
winter
Cultural
Tourism
>
50 million visitors
annually to Poyang
Lake region
Increasing
Economic development and
growing conservation
awareness
Global and
National scale
impact
Research and
education
Base for long-term
ecological
observation and
monitoring
Increasing research and
environmental
education
Awareness of the
significance of the
ecosystem
Global and
national
