摘要
对柘林湾代表性水区柱状样沉积物中不同形态氮、磷的含量进行了分析,研究了其垂直分布规律及其历史演变趋势。研究结果显示,除湾西北三百门(S2站)和湾中央大规模网箱渔排养殖区中心(S6站)外,其余各测站柱状沉积物中的有机氮(TOM)、凯氏氮(TKN)及各形态磷含量基本呈现"沉降-降解-堆积"三阶段的分布特征,反映了成岩作用的结果。S2、S6测站柱状沉积物中的多项氮磷指标,在表层10 cm以深不降反升与这两测站的高污染压力和弱水体交换能力导致的污染物快速堆积有关。底栖动物对沉积物垂直方向的扰动可能是各氮磷指标在沉降和降解阶段产生波动变化的重要原因之一,但生物扰动对NH4+的垂直变化影响最大。自生磷(Au-P)与有机磷(OP)在表层以下随深度呈一定的镜像关系,与Au-P和OP在成岩过程中的相互转化有关。Au-P随深度的变化幅度比OP的大,表明磷在Au-P和OP之间的转移并不是磷再分配的唯一途径,其它形态的磷也可能参与磷的再分配,而两者在表层不呈镜像关系主要与微生物对两者的降解有关。
The main objects of this thesis are to describe the vertical distributions and historical developmental tendency of nitrogen and phosphorus forms in the sediments at nine key sampling stations of Zhelin Bay. The results showed that except for S2 and S6 where are located in Sanbaimen northwest of the bay and the center of a large-scale cage-fish culture, respectively, vertical profiles of TOM (total organic nitrogen), TKN (Kjeldhal nitrogen) and phosphorus forms in all other stations generally presented such a characteristic with three stages of "deposition-decomposition-accumulation" resulted from diagenesis. Some nitrogen and phosphorus forms in S2 and S6 did not decrease but increase in the cores below 10 cm, indicating the fast accumulation of pollutants resulted from high pollution and weak water exchanging in these waters. Vertical bio-disturbance from zoo-benthos might be one of the most important factors to cause fluctuant change of concentrations of nitrogen and phosphorus forms with depth in deposition and decomposition stages. However, vertical bio-disturbance affected NH4^+ the most significantly. Au-P (authigenic phosphorus) and OP (organic phosphorus) mirrored with each other below the subsurface, suggesting that a transformation between them is not the only way of phosphorus redistribution, and other forms may be related with that. No mirror relationship between Au-P and OP found in the subsurface might be because of the decomposition of microbials.
出处
《海洋科学》
CAS
CSCD
北大核心
2007年第6期43-51,共9页
Marine Sciences
基金
广东省自然科学基金资助项目(021260)
广东省重大科技兴海项目(A200005F02)
广东省科技计划项目(2006A36502001)
关键词
柘林湾
沉积物
垂直分布
氮
磷
Zhelin Bay
sediment
nitrogen
phosphorus