巢湖底泥磷的释放模拟实验研究

Simulated study on phosphorus release of Chao Lake sediment

在实验室条件下 ,模拟了DO控制、pH值调节、温度调节、水动力条件等 ,进行了底泥释磷实验 .实验表明 :(1)厌氧条件下 ,底泥中的磷向水体释放 ,且释放强度随pH值的升高而升高 .好氧条件下 ,底泥非但没有向水体释放磷 ,反而从水体中吸附磷 ,呈“负释放”状态 ;且pH值越低 ,“负释放强度”越大 .(2 )温度升高有利于底泥中磷的释放 ,最大释放强度随温度的升高而提前 .(3)搅动条件下的底泥磷释放量大于静置条件下的底泥磷释放量 .(4)微生物对磷释放有明显的影响 .从本次模拟实验结果看 ,体系温度升高、减少溶解氧、提高pH以及施以水动力作用 ,均可使底泥中的磷释放量增加 ,在常温 (2 5℃ )、厌氧、pH =7 5条件下 ,底泥中磷向水体的释放量将增加 17%左右 .

The sediment phosphorus release study was similated by controlling of DO, pH, temperature and hydrodynamic condition under the lab condition. The results are showed that: (1) Under the anaerobic condition, the sediment phosphorus release to water and the release intensity increased with the increase of pH value and under aerobic condition, the sediment absorbed phosphorus from water and the absorb intensity is keeping with pH value decrease; (2) High temperature profits sediment phosphorus released to water, and the maximum released intensity increased with the increase of temperature; (3) The amount of sediment phosphorus release under the stirring condition was more than the one under still condition. (4) Microbe affected the sediment phosphorus release obviously. Under T =25℃, pH=7\^5 and anaerobic condition, the phosphorus release amount coued increased about 17%.