大气湿沉降对营养盐向长江口输入及水域富营养化的影响

通过对收集资料的分析,初步探讨了大气湿沉降对营养盐向长江口输入及其富营养化的影响。结果表明长江口区降水中无机氮浓度从上世纪90年代开始呈增长的趋势,到90年代后期又有所下降,但仍保持较高的水平.长江口湿沉降的营养盐年输入通量远小于河流,但短期输入通量很大.降水过程本身可形成很重要的非点源污染,加速水域短期富营养化,此外降水会改变表层的营养盐结构、盐度、pH等,进而影响到水域生物的群落结构.随着城市化的不断发展,长江三角洲地区降水增加,暴雨出现日数增多,降水对河口水域富营养化的短期效应更加突出,应引起广泛关注.

Effect of atmospheric wet deposition on nutrients into Changjiang Estuary and eutrophication

Based on the collected data, the effect of the atmospheric wet deposition on the nutrients into Changjiang estuary and eutrophication was primarily discussed. The results showed that the inorganic nitrogen in the rainwater of Changjiang estuary was increased from the beginning of 90^th of the last century, then decreased a little, but kept a high level. The annual nutrient flux into Changjiang Estuary from the atmospheric wet deposition was much less than rivers, but in short time, the atmospheric wet deposition flux was very high. The precipitation process can form the serious non-point pollution source, and accelerates the short-term eutrophication in the water area. Otherwise, the precipitation can change the nutrients structure, salinity, pH and biologic community in the surface water. With the urbanization developing, the precipitation and rainstorm manifold was increased, the short-term eutropication is more remarkable in the Changjiang estuary.