海州湾海洋牧场海域表层沉积物磷的形态与环境意义

采用沉积物无机磷分级方法结合上覆水初级生产力测定研究了海州湾海洋牧场海域表层沉积物磷的赋存形态及其生物有效性.结果表明:夏季总磷的含量高于春、秋两季,赋存形态以无机磷为主,平均占总磷的45.50%,各无机磷赋存形态的含量大小依次为:残渣态磷钙结合态磷铁铝结合态磷可交换态磷.其中可交换态磷、铁铝结合态磷以及钙结合态磷与有机碳含量成显著正相关(P0.01,R0.8).平面分布整体上呈现由近岸向远岸减小的趋势,这主要与陆源物质排放及沉积物自身质地有关.沉积物中的生物有效磷含量占总磷的36.95%,所占比例较大.

The distribution of phosphorus forms and its environmental significance in the marine ranching. demonstration area of Haizhou Bay sediment

The chemical speciation of phosphorus as well as its bioavailability of the marine ranching demonstration area of Haizhou Bay sediment was investigated by the grading methods for inorganic phosphorus in combination with the determination of the overlying water primary productivity. The results showed that the content of TP in summer was significantly higher than the spring and autumn, Inorganic phosphorus (IP) was the most abundant form, which accounted for 45.50% of TP. Content of inorganic phosphorus fractions in the surface sediment followed the order: residual inorganic phosphorus (Re-P)>calcium bound phosphorus (Ca-P)>Fe and Al-bound phosphorus ((Fe+Al)-P)>exchangeable phosphorus (Ex-P). Ex-P, (Fe+Al)-P and Ca-P had positive correlation with organic carbon content (P<0.01, R>0.8). Phosphorus content in surface sediments decreased from inshore to open sea of Haizhou Bay. This trend can be mainly attributed to the effects of terrigenous input and the sediment texture. The potentially biological available phosphorus (BAP) accounted for a large proportion (36.95%) of TP.