Water organic pollution and eutrophication influence soil microbial processes, increasing soil respiration of estuarine wetlands: site study in jiuduansha wetland.
Yue Zhang, Lei Wang, Yu Hu, Xuefei Xi, Yushu Tang, Jinhai Chen, Xiaohua Fu, Ying Sun
Author Information
Yue Zhang: Key Laboratory of Yangtze River Water Environment, Ministry of Education, School of Environmental Science and Engineering, Tongji University, Shanghai, China.
Lei Wang: Key Laboratory of Yangtze River Water Environment, Ministry of Education, School of Environmental Science and Engineering, Tongji University, Shanghai, China.
Yu Hu: Key Laboratory of Yangtze River Water Environment, Ministry of Education, School of Environmental Science and Engineering, Tongji University, Shanghai, China.
Xuefei Xi: Key Laboratory of Yangtze River Water Environment, Ministry of Education, School of Environmental Science and Engineering, Tongji University, Shanghai, China.
Yushu Tang: Key Laboratory of Yangtze River Water Environment, Ministry of Education, School of Environmental Science and Engineering, Tongji University, Shanghai, China.
Jinhai Chen: Key Laboratory of Yangtze River Water Environment, Ministry of Education, School of Environmental Science and Engineering, Tongji University, Shanghai, China.
Xiaohua Fu: Key Laboratory of Yangtze River Water Environment, Ministry of Education, School of Environmental Science and Engineering, Tongji University, Shanghai, China.
Undisturbed natural wetlands are important carbon sinks due to their low soil respiration. When compared with inland alpine wetlands, estuarine wetlands in densely populated areas are subjected to great pressure associated with environmental pollution. However, the effects of water pollution and eutrophication on soil respiration of estuarine and their mechanism have still not been thoroughly investigated. In this study, two representative zones of a tidal wetland located in the upstream and downstream were investigated to determine the effects of water organic pollution and eutrophication on soil respiration of estuarine wetlands and its mechanism. The results showed that eutrophication, which is a result of there being an excess of nutrients including nitrogen and phosphorus, and organic pollutants in the water near Shang shoal located upstream were higher than in downstream Xia shoal. Due to the absorption and interception function of shoals, there to be more nitrogen, phosphorus and organic matter in Shang shoal soil than in Xia shoal. Abundant nitrogen, phosphorus and organic carbon input to soil of Shang shoal promoted reproduction and growth of some highly heterotrophic metabolic microorganisms such as β-Proteobacteria, γ-Proteobacteria and Acidobacteria which is not conducive to carbon sequestration. These results imply that the performance of pollutant interception and purification function of estuarine wetlands may weaken their carbon sequestration function to some extent.
