Abstract:The distribution characteristics of total nitrogen and bioavailable nitrogen form was analyzed by chemical sequential extraction method in eight representive sediment samples collected from Dianchi Lake. The factors that influence the release of nitrogen form and its potential risk to the overlying water were discussed. The result showed that the concentrations of total nitrogen (TN) ranged from 1888.8mg/kg to 3155.8mg/kg and the relative concentrations of different nitrogen form ranked according to the following sequence: residual nitrogen (Residual-N, 46.2%~66.3%) > strong oxidant extractable nitrogen (SOEF-N, 22.9%~42.9%) > ion exchangeable nitrogen (IEF-N, 4.5%~7.5%) > weak acid extractable nitrogen (WAEF-N, 2.2%~4.0%) > strong alkali extratable nitrogen (SAEF-N, 2.7%~3.8%). IEF-N, WAEF-N, SAEF-N and SOEF-N were the potential bioavailable nitrogen form. The highest content of bioavailable nitrogen in the sediments from HG was consistent with the eutrophication degree of this area. The nitrogen concentration in the overlying water was closely related to the distribution of IEF-N from the sediments. SOEF-N was an important source of nitrogen in the overlying water. Moreover, NH4+-N was the main component of IEF-N, WAEF-N and SAEF-N. However the concentrations of NH4+-N were relatively lower in the sediments from HG where cyanobateria blooms seriously, indicating that the coupling relationship between cyanobateria blooming and the cycle of nitrogen in the sediments.
朱元荣, 张润宇, 吴丰昌. 滇池沉积物中氮的地球化学特征及其对水环境的影响[J]. 中国环境科学, 2011, 31(6): 978-983.
ZHU Yuan-Rong, ZHANG Run-Yu, WU Feng-Chang. Geochemical characteristics and influence to overlying water of nitrogen in the sediments from Dianchi Lake. CHINA ENVIRONMENTAL SCIENCECE, 2011, 31(6): 978-983.