中文摘要：

【正】 磷与硅作为重要的生源要素,其生物地球化学循环直接与海洋资源的可持续利用及全球变化密切相关。大量的研究表明,磷、硅等生源要素某一项的缺乏,都可限制该海域生物的繁殖生长,而成为生物生长繁殖的限制性因素(宋金明,1997;Conley et al.,1992;Riebesell et al.,1993;Thomposon et al.,1996);而某一生源要素的大量过剩,又可引起严重的富营养化,赤潮就是其典型的结果之一(齐雨藻等,1994;Eigenher et

英文摘要：

A new concept, "Form of element in natural grain size sediments (FNG)", was used studying the existence forms of phosphorous and silicon in five southern Bohai sea core sediments. FNG can yiled the information which part of these biogenic matter contained in marine particulates can really participate in the cycling and what functions they have in the cycling, which are two key issues dealt with in research on the cycling of marine biogenic elements. FNG provides a sound basis for research of transferable form biogenic elements contained in particulate matter.In the studied southern Bohai Sea core sediments, P exists mainly in the form of organic matter, Si exists mainly in the form of carbonate-boned. Transferable phosphorus accounts for only 17.4% (about 1.7 μmol/g) of total phosphorus and transferable silicon accounts for 0. 116% (about 11.9 μmol/g) total silicon in surface sediments, which show that only a small part of P and Si in sediments can participate in the biogeochemical processes. The transferable P and Si in natural grain size marine sediments are in leachable forms, different from previously known teachable P and Si obtained from total fine grain sediments.The transferable forms of P and Si have clearly different characteristics because of rediagenesis in the total core sediments. In the deep layer of the core sediments, the stable forms can activate and become transferable forms. Therefore, the transferable P and Si in the deep layer are more than those in the shallow layers at some sites such as M9-5, M6-5, M9-12.