上覆水环境条件对底泥氮磷释放的影响研究

Study on effect of overlying water environment on the nitrogen and phosphorus release of sediment

研究了不同温度、pH、DO环境条件下底泥对上覆水总氮、总磷释放强度的影响。结果表明:(1)随着温度升高,总氮、总磷释放强度增加;中性(pH=7)不利于底泥总氮、总磷的释放,强碱性(pH=10)条件下总氮、总磷释放强度最大;底泥中总氮、总磷的释放强度总体随DO浓度的升高而降低。(2)底泥中总氮平均释放强度与温度(R^2为0.998)的关系符合二次曲线,与pH(R^2为0.976)和DO(R^2为1.000)的关系都符合三次曲线;总磷平均释放强度与温度(R^2为0.999)、pH(R^2为0.999)和DO(R^2为1.000)的关系均符合三次曲线。(3)极差分析发现,环境条件对底泥总氮释放影响的大小表现为温度>DO>pH,对底泥总磷释放影响的大小表现为pH>温度>DO。

The influences of different temperature,pH and DO conditions on the total nitrogen and total phosphorus release intensity of sediment to overlying water were studied.Results showed that:(1)With the increase of temperature,total nitrogen and total phosphorus release intensity increased;neutral(pH=7)could hinder total nitrogen and total phosphorus release and strong alkaline(pH=10)made total nitrogen and total phosphorus release intensity largest;the release intensity of total nitrogen and total phosphorus in the sediment decreased with DO in general.(2)The total nitrogen average release intensity fit quadratic curve with temperature(R^2=0.998),and that fit cubic curve with pH(R^2=0.976)and DO(R^2=1.000);the total phosphorus average release intensity all fit cubic curve with temperature(R^2=0.999),pH(R^2=0.999)and DO(R^2=1.000).(3)Range analysis indicated that the influences of environmental factors on the total nitrogen release were temperature>DO>pH,and those on the total phosphorus release pH>temperature>DO.