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Critical loads of headwater streams in China using SSWC model modified by comprehensive F-factor
Dongwei Lv1, Qian Yu1, Danni Xie2
1State Key Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
The Science of the Total Environment
|August 30, 2021
Summary
China
Area of Science:
- Environmental Chemistry
- Ecosystem Recovery
- Acid Deposition Modeling
Background:
- Acid deposition poses a risk to surface water quality.
- Assessing ecosystem recovery is crucial after policy interventions.
- China's historical acid deposition requires updated risk assessments.
Purpose of the Study:
- To evaluate surface water acidification risks in China.
- To measure ecosystem recovery from acid deposition.
- To estimate critical loads and exceedances for headwater streams.
Main Methods:
- Utilized a modified Sulfate Sulfur Water Chemistry (SSWC) model.
- Analyzed data from 349 headwater streams across China.
- Considered acid-neutralizing capacity and ion retention in the model.
Main Results:
- China's streams exhibit higher critical loads than Europe and North America.
- Acid deposition exceedances decreased from 40.4% in 2005 to 29.5% in 2018.
- Southeast China shows a persistent high risk of acidification.
Conclusions:
- Emission abatement policies have reduced surface water acidification risks.
- Continued emission control is necessary, especially in southeast China.
- China's aquatic ecosystems show signs of recovery but require ongoing monitoring.
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