Nitrogen evolution with distance of 10 inflow rivers in the three circles of buffer zone around Erhai Lake
LU Shao-yong1, ZHANG Wen-tao1,2, XING Yi2
1. Engineering and Technology Center of Lake, State Environmental Protection Scientific Observation and Research Station for Lake Dongtinghu, Research Centre of Lake Environment, State Environmental Protection Key Laboratory for Lake Pollution Control, State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China;
2. Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083, China
Surface water of 34 monitoring sections in 10inflow rivers, which were located at the 3 ribbon sections (inner, outer and middle) of the buffer zone of Erhai Lake, was sampled in July 2013. The water quality including total nitrogen, dissolved total nitrogen and ammonia nitrogen was measured and the spatial variabilities of selected water quality parameters were analyzed, aiming at put forward reasonable suggestions for the lack of function and establishment and improvement of the buffer zone. The results showed that there were 9 categories of the variation of water quality in ribbon sections, i.e., rise continuously, reduce continuously, first reduce then rise emerge “V” shape, first rise then reduce emerge inverted “V” shape, gently, first rise then steady, first reduce then steady, first keep gently then reduce, first keep gently then rise. The average ρ(TN) in 10inflow rivers of Erhai Lake was 2.93mg/L. The average ρ(TN) of estuary in the inner ribbon section was 3.74mg/L, which was a threat to the lake. So improving the collection network of sewage and garbage disposal facilities was very important in the inner ribbon section. At the same time, management strengthen of rivers should be made. ρ(DTN) of Mangyongxi River, Heilongxi River and Qingbixi River in the buffer zone were changed between 0.30mg/L and 2.31mg/L, occupying 81% of ρ(TN) averagely. The nitrogen load of the 3 rivers in the middle ribbon section in the buffer zone was obviously higher than that in the inner and outer parts. Therefore, the use of fertilizer in the farmland should be controlled so that reducing nitrogen losses with the runoff. Ecological gravel bed, ecological pond and underground infiltration pond and other ecological purification engineering measures should be built in the outer ribbon section, considering the water quality began to deteriorate from the middle reaches.
卢少勇, 张闻涛, 邢奕. 洱海10条入湖河流缓冲带三圈内氮含量沿程变化[J]. 中国环境科学, 2016, 36(5): 1561-1567.
LU Shao-yong, ZHANG Wen-tao, XING Yi. Nitrogen evolution with distance of 10 inflow rivers in the three circles of buffer zone around Erhai Lake. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(5): 1561-1567.
Buckley C, Hynes S, Mechan S. Supply of an ecosystem service-Farmers' willingness to adopt riparian buffer zones in agricultural catchments [J]. Environmental Science & Policy, 2012,24:101-109.
[2]
Zhao P, Xia B, Hu Y, et al. A spatial multi-criteria planning scheme for evaluating riparian buffer restoration priorities [J]. Ecological Engineering, 2013,54:155-164.
[3]
Johnson S R, Burchell M R, Evans R O, et al. Riparian buffer located in an upland landscape position does not enhance nitrate-nitrogen removal [J]. Ecological Engineering, 2013,52: 252-261.
[4]
Dorioz J M, Wang D, Poulenard J, et al. The effect of grass buffer strips on phosphorus dynamics—A critical review and synthesis as a basis for application in agricultural landscapes in France [J]. Agriculture, Ecosystems & Environment, 2006,117(1):4-21.
