防城湾水质特征及营养状况趋势研究

根据1983—1984年度、1990年度及1996——1997年度3个不同时期的调查研究资料，分析研究了防城湾的水质特征及其营养状况。结果表明：该湾水体中的盐度、pH呈明显下降趋势，而有机污染物含量则呈上升趋势，其余因子无明显规律性变化；但相关分析显示，陆源输入对各化学因子具有主导控制作用，生物同化作用次之。N、P、Si营养盐中，N为1983—1984年度初级生产力的限制因子：1990年度演化为P和Si;1996—1997年度N、P、Si均呈充足状态，尤以Si最为显著。通过污染指数A及营养状态指数E的统计分析，该湾水质具有向污染型及富营养型演化的明显趋势。

AStudy on the Tendency of Water Quality and Nutrient Condition in Fangcheng Bay

Based on the investigations carried out in the periods of 1983 to 1984, 1990 and 1996 to 1997 respectively, the water quality and nutrient condition in the waters of Fangcheng Bay are studied. The results show that the salinity and pH decrease and the organic pollutant increases obviously, while the other factors have no manifest law of tendency. According to the correlation analysis, the terrigenous inputs play a dominant controlling role of affecting the chemical factors, and the biological assimilation affects them less. Among the three types of nutrient salt, N is the limiting factor on the primitive productivity in the period of 1983 to 1984, and P and Si in 1990. The three types of nutrient salt, especially Si, are abundant from of 1996 to 1997. After statistical analysis by pollution index A and nutrient condition index E, it turns out that the water quality in this bay has transformed to the pollution and eutrophication type.