温亚军 胡志逵

摘 要：在一定的环境条件下，底泥能够释放磷，引起水体富营养化。通过研究不同pH、温度和溶解氧（DO）对谷河底泥磷释放的影响，结果表明，pH显著影响底泥磷的释放，碱性环境比酸性环境磷释放强度大，中性环境不利于底泥磷的释放;温度升高，磷释放强度增加;厌氧环境比好氧环境更能促使底泥磷的释放。正交模拟试验结果显示，3个因素均是影响谷河底泥磷释放的显著因素，影响因素显著性从大到小依次为DO>温度>pH。

关键词：底泥;磷释放;正交实验

中图分类号 X522文献标识码 A文章编号 1007-7731（2021）11-0143-03

Research on Remarkable Affecting Factors of Phosphorus Release from Gu River Sediments

WEN Yajun et al.

（Fuyang Institute of Environmental Protection Science and Technology， Fuyang 236000， China）

Abstract： Sediments can release Phosphorus into overlying water under certain conditions， which may have a significant impact on water quality and result in continuous eutrophication. We used laboratory experiments to evaluate effects of pH， temperature and Dissolved Oxygen on P release from River GU. The results demonstrate that effects of pH on P release from sediments were distinct; more P was released under alkaline conditions than acidic conditions， but the least amount of P was released under neutral pH. Increasing temperature resulted in more release of P between sediment P release and P in overlying water. Anaerobic conditions were more conducive to the release of P than aerobic conditions. Orthogonal experiments show that the 3 significant factors on P release from sediments were， in descending order， DO， temperature， and pH.

Key words： Sediments; Phosphorus release; Orthogonal experiments

底泥作为自然水域的重要组成部分，主要通过自然的过程及人类的行为，在水体底部逐渐形成的沉积物。受上覆水的影响，底泥在水体的营养盐循环中既可扮演“汇”的角色，也可扮演“源”的角色。水体污染严重时，氮磷营养盐可通过沉降或者顆粒吸附作用而聚集于底泥中，再悬浮作用又会向上覆水释放氮磷营养盐[1]。经研究表明，底泥中氮磷营养物的释放是影响水体中浮游生物生长和水质富营养化的关键过程之一，往往底泥中氮磷的加速或过度释放会引起水体富营养化的加剧，造成水体的二次污染[2]。磷释放受各种环境因子的影响，底泥中释放的磷首先进入底泥间隙水，这是释磷速率的决定步骤。释磷与化学沉淀形态有关，一旦出现利于钙、铁、铝等不溶性磷酸盐沉淀物溶解的条件，磷就释放，释放物质逐步扩散到沉积物表面，进而向上覆水混合扩散，成为水体总磷的一部分[3]。