【摘要】 为了解水库上覆水环境对底泥释磷强度的影响,确定底泥释磷强度与环境要素的定量线性关系,阐明不同水环境条件下底泥释磷机理。2014年8月对大河口水库采集底泥样品,进行了4因素(水温、pH、水动力、溶解氧)5水平底泥释磷室内模拟试验。结果表明:(1)温度升高有利于底泥磷的释放,25℃条件下底泥平均释磷强度为30.04 mg/m2,是5℃条件下释磷强度9.01 mg/m~2的3.3倍。(2)强酸碱条件均有利于底泥磷释放,中性条件下底泥释磷强度最小,试验期内强碱条件下(pH=9.5)底泥释磷强度分别是强酸条件(pH=5.5)和中性条件(pH=7.0)释磷强度的1.1倍和1.9倍。(3)增加扰动可加速泥水界面交换,促进底泥磷释放。高强度扰动下底泥最大释磷强度为25.18 mg/m~2,是静置条件下的3.8倍。(4)随溶解氧浓度增大底泥释磷强度呈下降趋势。DO为6.5 mg/L以上时,底泥释磷呈现"负释放"状态。(5)底泥释磷强度与温度、pH、水动力环境因素二次函数曲线拟合最优,与溶解氧三次函数曲线拟合最优。更多还原

【Abstract】 The study aims at understanding the influence of the reservoir overlying water environment change on the intensity of sediment phosphorus release, clarifying the quantitative linear relationship between phosphorus release intensity and envi-ronmental factors, as well as providing scientific basis for the treatment of eutrophication in reservoir. Sediment samples were collected from Dahekou Reservior in August 2014, the mechanism of phosphorus release from sediment under different water temperature, pH, water power and dissolved oxygen environment was analyzed. The results showed that increase of tempera-ture is conducive to the release of phosphorus from sediments. Under the conditions of 25 ℃,the average phosphorus release intensity was 30.04 mg/m2, which was 3.3 times of the phosphorus release intensity of 9.01 mg/m~2 at 5 ℃. Strong acid or alkaline conditions were conducive to the release of sediment phosphorus, test period under alkaline conditions(pH =9.5) of sediment phosphorus release intensity are as 1.1 times and 1.9 times respectively as that under the strong acid condition(pH=5.5) and neutral conditions(pH=7.0). The perturbation can accelerate water interface exchange and promote the phosphorus release from sediment. Under high strength disturbance, the maximum sediment phosphorus release intensity is 25.18 mg/m~2,3.8 times of static conditions. With the increase of dissolved oxygen, concentration of sediment phosphorus release intensity decreased. When DO is above 6.5 mg/L, the sediment phosphorus release shows "negative release". The sediment phosphorus release intensity fits well with quadratic function curve of environment factors such as temperature, pH and hydrodynamics,also fits well with the cubic function curve of dissolved oxygen.更多还原