Probability-based nitrate contamination map of groundwater in Kinmen
Chen-Wuing Liu1, Yeuh-Bin Wang, Cheng-Shin Jang
1Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan, 106, Republic of China, lcw@gwater.agec.ntu.edu.tw.
Environmental Monitoring and Assessment
|July 30, 2013
Summary
High nitrate-nitrogen levels in Kinmen
Area of Science:
- Environmental Science
- Hydrogeology
- Water Quality Management
Background:
- Groundwater is Kinmen's primary drinking water source, with 16.8% of samples exceeding the nitrate-nitrogen drinking water standard (DWQS).
- High nitrate-nitrogen groundwater poses significant health risks to residents.
Purpose of the Study:
- To develop an efficient logistic regression (LR) model for evaluating the spatial distribution of nitrate-nitrogen in Kinmen's residential groundwater.
- To create a probability-based nitrate-nitrogen contamination map for effective water quality management.
Main Methods:
- A logistic regression (LR) model was employed to predict the probability of nitrate-nitrogen exceeding the DWQS.
- Key independent variables included soil type, pH, and electrical conductivity (EC).
- A predictive EC-pH-probability curve was developed for preliminary screening.
Main Results:
- The LR model achieved a 92.7% correct classification rate.
- Soil type, pH, and EC were identified as significant predictors of nitrate-nitrogen contamination.
- The central zone of Kinmen showed the highest probability of contamination, rendering its groundwater unsafe for drinking.
Conclusions:
- The developed LR model and EC-pH-probability curve offer efficient tools for assessing groundwater nitrate-nitrogen contamination.
- Targeted management strategies and systematic monitoring are crucial for high-risk zones to ensure safe drinking water in Kinmen.
