2006-2007年珠江口富营养化水平的季节性变化及其与环境因子的关系

Seasonal variations of eutrophication and the relationship with environmental factors in the Zhujiang Estuary in 2006—2007

以珠江口海域2006-2007年丰水期、平水期和枯水期的水质监测结果为基础,采用改良后的营养状态指数法,并结合CN/CP(物质的量比)的潜在性富营养化划分方法,对该海域在3个水期的富营养化水平进行评价,同时对富营养化指数与环境因子的关系进行讨论。结果表明:由营养状态指数值和CN/CP值的总体评价结果来看,珠江口海域的富营养化程度较高,属于磷限制潜在性富营养区;在时空分布上,珠江口海域富营养化程度呈现由湾内向湾外递减的趋势,不同水期的富营养化水平从高到低的顺序依次为:枯水期、丰水期、平水期;富营养化水平的时空变化主要受地表径流的影响。

Seasonal variations of eutrophication in the Zhujiang Estuary were examined based on data from three surveys during the wet, temperate and dry seasons from 2006 to 2007. A modified method of nutrient status index and CN/CF value were used in analysis, and the relationship between eutrophication index and environmental factors was discussed. It concluded that the eutrophication in the Zhujiang Estuary was high, and this area could be classified as a phosphorus--limited potential eutrophication area. The eu- trophication index decreased along the estuary from north to south in spatial distribution, and eutrophica- tion index showed a sequence of dry season greater than wet season greater than temperate season in the seasonal variation. The temporal and spatial distributions of eutrophication index were mostly regulated by runoff.