沉水植物黑藻对沉积物氨氮吸附/释放特征的影响

Effect of submerged aquatic plant Hydrilla verticilla on the sorption/release characteristic of ammonia nitrogen on sediment

氮素是主要的湖泊营养盐,而沉水植物作为湖泊生态系统主要的组成部分,对系统中氮素的跨界面迁移有着重要的影响。在实验室模拟条件下,通过沉积物氨氮释放动力学、吸附热力学和吸附动力学实验,研究了沉水植物黑藻(Hydrilla verticilla)对沉积物氨氮吸附/释放特征的影响,得到如下结论:(1)一级动力学反应模型能较好地拟合沉积物氨氮释放的动力学过程,种植沉水植物没有影响氨氮释放的趋势,但增强了沉积物释放氨氮的能力;(2)分别用多个模型对沉积物氨氮吸附热力学和动力学过程进行拟合,结果均表明种植沉水植物以后,沉积物对氨氮吸附的趋势没有影响,但吸附强度有所下降。

Nitrogen is one of the nutrients in many shallow lakes, and submerged aquatic plant is the major component among the lake ecosystem that is of significance to the transference and transform of nitrogen cycling in shallow lake systems. In this study, the ammonium sorption/release kinetic and sorption thermodynamic processes were investigated in simulating condition to discover the effects of Hydrilla verticilla, submerged aquatic plant, on the sorption/release characteristic of ammonium on sediment, The results indicated that： （1）The First Order model can well describe the release kinetics of ammonia nitrogen on sediment, the existing of submerged aquatic plant Hydrilla verticilla can not affect this release trend, but the release strength of ammonia nitrogen on sediment was improved. （2）The sorption kinetics and the sorption thermodynamics data were fitted well by several models, respectively. The existing of submerged aquatic plant Hydrilla verticilla can not affect this release trend, but the sorption strength of ammonia nitrogen on sediment was decreased.