用成岩模型计算沉积物水界面营养盐的交换通量——以渤海为例  

Exchange Fluxes of Nutrients at Sediment-Water Interface Calculated by the Diagenesis Model: the Bohai Sea

作　　者：刘素美[1] 江文胜[1] 张经[2] 

机构地区：[1]中国海洋大学山东青岛266003 [2]中国海洋大学山东青岛266003华东师范大学上海200062

出　　处：《中国海洋大学学报（自然科学版）》2005年第1期145-151,共7页Periodical of Ocean University of China

基　　金：国家重点基础研究发展规划项目 (G1 9990 4 37;2 0 0 1CB40 97);国家自然科学基金项目 (40 2 0 60 1 7)资助

摘　　要：根据沉积物中营养盐的再生对水体中营养盐的收支循环动力学的作用。利用 1998年秋季和 1999年春季沉积物间隙水中营养盐的分析结果 ,建立了沉积物中营养盐的成岩模型 ,并由此计算了沉积物 水界面营养盐的交换通量。结果表明 ,硝化速率、反硝化速率、有机氮含量、硅质成分的溶解速率、生物扰动作用、孔隙率明显影响沉积物间隙水中营养盐的分布和沉积物 水界面的交换通量。对比了实验室培养法和扩散通量计算法测得沉积物 水界面营养盐的交换通量 ,表明 2种方法所得NO-3 通量较一致 ,但NH4+ ,PO43 -,SiO3 2 -2种方法所得通量有一定差异 ,文中讨论了可能的原因。以渤海为例阐明了在用扩散通量法研究沉积物 水界面营养盐的交换通量时 ,表层沉积物分割厚度对界面交换通量影响显著 ,为了得到合理的与现场接近的结果表层沉积物的分割厚度以不超过 1cm为宜。The nutrient regeneration in the sediment plays an important role in the budget and dynamics of nutrients recycling in the water column. The nutrients in pore waters of sediments were investigated in autumn 1998 and spring 1999 in the Bohai Sea. The diagenesis models were developed for nutrients in sediments, the exchange fluxes of nutrients were calculated from the models. The results demonstrated that nitrification rate, denitrification rate, organic nitrogen content, the dissolved rate of siliceous material, bioturbation, and porosity affect the distribution of nutrients in the pore waters and exchange fluxes of nutrients at the sediment-water interface. Comparison between the exchange fluxes determined from the interstitial water profiles and those from measuring the concentration changes in the overlying water by incubating the intact sediment core in the laboratory on board the research ship shows that the exchange fluxes of nitrate by these two methods were consistent with each other, while the others showed obvious difference. The possible reasons for this are discussed in this work. This study demonstrates that the depth interval has an important effect on the determination of exchange fluxes of nutrients. The depth interval should be as small as possible, so that the benthic fluxes of nutrients are close to the real results.

关 键 词：沉积物-水界面 营养盐 通量 成岩模型 渤海 

分 类 号：P734[天文地球—海洋化学]