【摘要】 以湖滨湿地基质和原位上覆水为材料,分别模拟了在好氧及厌氧、不同pH值及不同上覆水初始磷浓度条件下基质中磷的释放特性和规律。研究结果表明,与好氧条件相比,厌氧状态大大促进了基质中磷的释放,且碱性条件下的释放最明显,而中性条件下的释放则较弱,释放强度随pH值的升高而升高。好氧条件下,基质向水体中释磷很少,有时甚至从水体中吸磷。当上覆水的初始磷浓度较低时,基质先向上覆水释磷,而后吸附直至达到平衡;随着上覆水初始磷浓度的升高,当基质中的磷含量低于上覆水中的磷浓度时,则从水体吸磷直至达到平衡。将不同环境因子相比较,上覆水为碱性条件(pH=11.3)时基质的释磷量最大,厌氧条件次之,上覆水的pH值增加和氧化还原电位降低是湿地基质释磷的主要机制。更多还原

【Abstract】 The substrate and in situ overlying water of constructed wetland in the riparian zones were used to simulate phosphorus release by controlling DO,different pH and initial TP concentrations of overlying water.The research results show that under the anaerobic condition,the substrate phosphorus release is more intense under alkaline condition compared to the acidic condition,and lowest under the neutral condition.The intensity of substrate phosphorus release is directly linear to the pH value.Under the aerobic condition,the substrate releases less phosphorus to the water and even absorbs phosphorus from overlying water.For low initial TP concentration in overlying water,the substrate first releases phosphorus to the water,then absorbs it until a balance is reached.As the initial concentration increases and the phosphorus in the substrate is less than that in the overlying water,the substrate absorbs phosphorus until the balance is reached.Through comparing different environmental factors,the alkaline condition of pH=11.3 shows the greatest amount of substrate phosphorus release.The anaerobic condition takes the second place.The primary mechanisms of substrate phosphorus release in the wetland are the increase of pH value and the decrease of the oxidation-reduction potential.更多还原