池塘残饵对底泥氮、磷释放影响的模拟研究

运用室内静态模拟的方法,设置静态释放组(A组)和饲料添加组(B组),研究了池塘残饵分解对底泥氮、磷释放的影响.结果表明,A组DO高于B组(P<0.05),A组pH值为中性,B组pH值呈弱酸性.添加饲料后,B组硝态氮低于A组(P<0.05),而B组活性磷高于A组(P<0.05).实验第2~14 d,A组氨氮高于B组(P<0.05),此后B组氨氮升高,实验结束时B组氨氮高于A组(P<0.05).研究表明,添加饲料的B组,初期氨氮和硝态氮的释放都受到抑制.静态释放的A组,氮的释放变化是先上升,后降低的趋势,而饲料添加的B组,氮的释放变化趋势则是先降低,后升高.B组饲料分解向上覆水释放大量的磷,活性磷的变化呈现先上升后下降的趋势.

Effect of Feed Residues on the Release of Nitrogen and Phosphorus of Pond Sediment

The effect of feed residues on release law of nitrogen and phosphorus in water-sediment interface was studied under the simulated condition in laboratory. Two sets of conditions were applied in this study, static condition (A group) and feed add condition (B group). The results show that DO in A group is higher than that in B group(P<0.05). The pH value is neutral in A group, but pH value of B group became weak acidic. After adding the feed, nitrate nitrogen concentration in A group is higher than that in B group(P<0.05), but orthophosphate concentration in A group is lower than that in B group(P<0.05). At the 2-14th day of experiment, ammonia concentration in A group is higher than that in B group(P<0.05), but since then the ammonia concentration in B group begins to rise. At the end of the test, ammonia concentration in B group is higher than that in A group(P<0.05). At the beginning of the experiment, ammonia and nitrate nitrogen release restrained in B group. Nitrogen increases first, and then decreases in A group, but the changing regulation is completely opposite in B group. Feed decomposition can produce a large amount of phosphorus in B group, at the same time, orthophosphate changing regulation increases first and then decreases.