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Updated: Jul 9, 2026
10:49
Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading
Published on: March 6, 2014
Nonpoint source pollution loading from an undistributed tropic forest area
Chih-Hua Chang1, Ching-Gung Wen, Chia-Hui Huang
1Department of Environmental Engineering, Sustainable Environment Research Center, National Cheng Kung University, Tainan, 70101, Taiwan. chchang@ckmail.ncku.edu.tw
Environmental Monitoring and Assessment
|December 13, 2007
Summary
Forest watershed pollution in Taiwan shows higher water quality parameter concentrations during rainy days. Major storm events significantly contribute to annual nonpoint source pollution loads, necessitating targeted management strategies.
Area of Science:
- Environmental Science
- Hydrology
- Forestry
Background:
- Nonpoint source (NPS) pollution from forest areas poses a significant challenge to water quality.
- Understanding NPS pollution dynamics in mountainous watersheds is crucial for effective environmental management.
Purpose of the Study:
- To investigate water quality and NPS pollution loads in a mountainous forest watershed in Taiwan.
- To quantify the impact of rainfall events on pollution loads and identify key drivers of pollutant transport.
Main Methods:
- Continuous monitoring of flow rates using rectangular weirs and water quality sampling over two years.
- Hydrological Simulation Program--FORTRAN used to simulate runoff for three additional years.
- Regression modeling to estimate total annual loads of various water quality parameters.
Main Results:
- Most water quality parameter concentrations were elevated during rainy days compared to non-rainy periods and other undisturbed forests.
- Suspended solids (SS) and total phosphorus (TP) concentrations showed positive correlations with flow rates.
- Six major storm events, lasting only 6.4 days, accounted for 42% of annual precipitation and at least 40% of annual NPS loads.
Conclusions:
- Annual NPS pollution loads from the studied forest watershed exhibit significant fluctuations, heavily influenced by major storm events.
- Effective management strategies are required to control NPS pollution from forest watersheds, particularly focusing on high-impact events.
- The findings provide valuable data for watershed management and policy development in similar ecosystems.
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