湖泊底泥氮营养释放特征研究

Nitrogen Release Characteristic of Dianchi Lake Sediment

通过模拟培养,研究了底泥氮营养的释放及上覆水体中氮营养的浓度变化特征。结果表明,在扰动下,底泥向上覆水体明显地释放氮营养,而消亡的水华更可以激发底泥中有机氮的释放,底泥中有机氮的矿化释放与沉积到底泥表层的水华量密切相关。释放进入上覆水体中氮首先以铵氮存在,并快速向亚硝氮转化,此后才向硝氮转化。水中铵氮浓度高,存在时间长,是比较主要的氮形态。

Nitrogen release characteristic of Dianchi lake sediment and the nitrogen of overlying water body was studied through simulating cultivation. The results disturbed sediment released N nutrients to overlying water body markedly. The dead nutnents concentration indicated that under cells of phytoplankton could promote organic nitrogen of sediment mineralization. The amount of nitrogen nutrients released of sediment was correlation with the amount of dead cells of phytoplankton being deposited. Ammonia was the main form of the nitrogen nutrient being released into overlying water body, and it was transformed to nitrite soon. And then nitrite was transformed to nitrate.