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Published on: September 6, 2018
Nitrogen flow analysis in Huizhou, South China
Xiaobo Ma1, Zhaoyin Wang, Zegao Yin
1College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
Environmental Management
|January 31, 2008
Summary
Nitrogen pollution from human activities is a major issue in Chinese rivers. This study found that Huizhou City retained 40% of its nitrogen, leading to potential environmental problems and significant riverine export.
Area of Science:
- Environmental Science
- Water Quality Management
- Ecosystem Dynamics
Background:
- Eutrophication from nitrogen and phosphorus discharges is a critical pollution issue in Chinese rivers.
- Understanding nitrogen cycling is essential for managing water quality in riverine ecosystems.
Purpose of the Study:
- To analyze nitrogen flows and identify major sources and pathways in Huizhou City, East River watershed.
- To quantify nitrogen retention and export within the study area for environmental impact assessment.
Main Methods:
- Material accounting method to track nitrogen flows within natural and anthropogenic systems.
- Export coefficient method for nonpoint source pollution quantification.
- Estimation of domestic discharge based on per capita contribution and population data.
Main Results:
- Major nitrogen flows identified include river loads, fertilizer/feedstuff imports, atmospheric deposition, and manure volatilization.
- Approximately 40% of nitrogen was retained within the Huizhou system in 1998, posing potential environmental risks.
- Riverine export constituted the largest portion (57%) of total nitrogen exported from the area.
Conclusions:
- Nitrogen retention and export dynamics in Huizhou City are significant, contributing to eutrophication concerns.
- The study highlights the comparable nitrogen export magnitudes per unit area and per capita with major rivers like the Danube and Yangtze.
- Findings underscore the need for targeted nitrogen management strategies in the East River watershed and similar regions.
