大亚湾沉积物中氮和磷的地球化学形态分配特征

DISTRIBUTION CHARACTERISTICS OF THE ENVIRONMENTAL GEOCHEMICAL FORMS FOR NITROGEN AND PHOSPHORUS IN THE SEDIMENTS OF DAYA BAY

本文介绍了大亚湾沉积物中N和P的地球化学形态(包括形态总量、有机态、无机态及其细分态)的分析方法,并对7个测站沉积物中该两元素的各种形态分配特征进行了研究。结果表明:N和P的总量、有机态和无机态都具有几乎完全相同的分布规律;N和P的主要地球化学形态分别是有机态和无机态,分别占各自总态的80％和60％左右,有机态中的N/P比值非常接近于浮游生物体中该两元素组成典型比值16;N和P的各种形态含量与其相关的结合成分都有较好的相关关系。

This paper presents the environmental geochemical forms for N and P in the sediments of Daya Bay. The geochemical forms including the total form content (NT,PT), organic bound form (N0, P0), inorganic bound form (NIN, PIN) and their fractionation forms i.e. exchangeable N(NEX) and nonexchangeable N(NNEX), Apatite P(PAI), and nonapatite P(PNAI) have been determined. The results show that. (1) content range of NT and PT is 1 200-1 980 and 460-560 ppm, average content is 1690 and 510 ppm respectively; (2) main form of N and P is N0 and (PIN) which accounts for about 80% and 60%, respectively; (3 ) in the organic form, the average ratio of N/P (atomic) is 15.9, which is close to the average of the two elements 16 in plankton) ( 4 ) in the inorganic form, NEX and NNEX account for about 1 % and 16%, PAI and PNAI account for 30.8% and 30.7%, respectively. In addition, correlationships between the geochemical forms and other compositions, such as organic matter, CaCO3 and Fe + Al etc. have been discussed.