厦门湾海域营养盐时空分布与富营养化状况分析

根据2010年8月厦门湾海水水质监测资料，阐述氮磷营养盐的变化趋势及其相互关系，并探讨厦门湾海域富营养化程度。结果表明，厦门湾表层COD、DIN和 PO4-P分布趋势大致从厦门西海域、马銮湾和九龙江口向湾外递减；相关性分析说明调查海域COD、DIN和PO4-P主要来源是厦门湾沿岸陆源排放和九龙江河流营养盐的输入；COD、PO4-P与N H4-N的来源可能相同，有着相似的生物地球化学过程，而NO3-N可能主要来源于九龙江。厦门湾的N/P值变化范围为2.26～117.30，其中九龙江口、东南部海域和大嶝海域的大部分地区的 N/P均大于16，从N/P值来看，营养盐结构为磷限制。而西海域北部、同安湾和马銮湾则属于氮限制海域。厦门湾海域富营养化指数（E ）范围为0.013～118.168，马銮湾、西海域北部和高集海堤附近海域的富营养化指数较高。

Analysis of the Space-time Distribution of Nutrients and the Degree of Eutrophication in Xiamen Bay

According to the data on water quality monitoring of seawater in Xiamen Bay in August 2010 ,this paper illustrated the variation trend of nitrogen and phosphorus nutrients and their mutual relations ,and discussed the eutrophication degree of the sea in Xiamen Bay .The results show that the distribution trend of surface COD ,DIN and PO4-P is roughly progressively decreasing from western sea of Xiamen ,Maluan Bay and Jiulong River Estuary to outside the bay ;Correlation analysis showed that the main source of COD ,DIN and PO4-P in the investigated sea was the input of nutrients from land-based emissions along the coast of Xiamen Bay and Jiulong River ;The sources of COD ,PO4-P and NH4-N might be the same ,which had similar biogeochemical process .While the main source of NO3-N might be Jiulong River .The variation range of N/P value of Xiamen Bay was 2.26~117.30 ,and the values of N/P in most areas of Jiulong River Estuary , southeastern sea and Dadeng sea area were greater than 16.According to the N/P value ,the structure of nutrients was phosphorus-restricted ,while the north of western sea area ,Tongan Bay and Maluan Bay belonged to nitrogen-restricted sea areas .The range of the eutrophication index of the sea area in Xiamen Bay （E） was 0.013~118.168 ,while the eutrophication indexs of Maluan Bay ,the north of western sea and the sea near Gaoji Seawall were higher .