中文摘要：

水体沉积物界面中磷的释放机制非常复杂，生物作用导致的pH值和氧化还原条件变化对湖泊沉积物矿化能力有显著影响。普遍认为沉积物中有机磷的矿化过程是对水体富营养化具有重要贡献的环节之一，而核酸态有机磷可从一定程度上表征微生物水平，反应微生物对矿化作用的影响。据此采用DNA提取的方法对沉积物中核酸态有机磷的含量进行测定，并模拟沉积物中核酸在不同pH和溶解氧条件下的矿化过程。结果表明，DNA提取方法可以快速、准确提取沉积物中核酸磷；沉积物中核酸磷含量为0．43～0．61μg·g^-1，占有机磷总量的0．27％～0．37％，精确度为1．58％～3．63％。模拟实验结果表明，在两种情况下上覆水中总磷浓度均呈波动式上升，在pH接近7时沉积物中核酸磷较低，有氧条件下核酸磷呈下降趋势。

英文摘要：

Mechanism of phosphorus releasing at the sediment-water interface is complex. Microbially induced changes in pH and redox potential strongly affect the ability of mineralization in lake sediments. The mineralization process of organic phosphorus in sediment is important to eutrophication, and organic phosphorus in nucleic acid form may represent the level of micro-organisms which indicates the mineralization process in a certain extent. In this paper, the method of DNA extracted from sediments and total phosphorus releasing from sediment to overlying water at different pH and aerobic/anaerobic conditions by experiments was studied. The method of DNA extracted from sediments used to analyze the organic phosphorus in nucleic acid form. The results showed that the contents of DNA-P are 0.43-0.61 μg ·g^-1 in sediment, account for about 0.27%-0.37% of total organic phosphorus, precisions are 1.58%-3.63%. Simulated experiments were set to understand the mineralization process in sediment at different pH and aerobic/anaerobic conditions. Results of two simulating experiments showed that the concentrations of TP in overlying water were fluctuating with increasing trend in general. The variation of DNA-P in sediment had no clear trend at different pH and the content of DNA-P in sediment was lower when pH near to 7. The result of aerobic and anaerobic simulated experiments showed that DNA-P in sediment was decearcing at aerobic condition.