中文摘要：

在风浪扰动条件下,沉积物再悬浮会造成重金属的二次释放。沉水植物可以有效地改变水流条件并抑制颗粒物再悬浮,从而一定程度地改善水体的生态环境。该文通过室内环形风动水槽模拟实验,利用ADV测流技术与悬浮颗粒物（SPM）浓度表征悬浮量的方法,分析不同水动力条件下沉水植物苦草对水流条件的影响及再悬浮过程8 h内SPM的浓度变化,并测定试验周期（35天）内重金属（Ni、Cd）于上覆水、间隙水及沉积物中的分布情况,研究不同水动力下水生植物对重金属再悬浮的影响规律。结果表明,在风速分别为3.21 m/s（小风）、5.95 m/s（中风）和8.78 m/s（大风）时3种风力的扰动作用下,植物有效高度内流速低且流速梯度小,而冠层至水面高度内流速梯度较大,水流结构以植物冠层为拐点,呈＂S＂形分布。上覆水SPM浓度与无植物时相比显著降低,沉积物再悬浮率下降量（W）与风速（v）呈对数关系（W=0.2194ln（v）-0.2445）。不同水动力条件下,重金属（Ni、Cd）在上覆水、间隙水及沉积物中分布情况及变化规律相似。试验期间间隙水与沉积物中重金属含量变化整体呈现下降趋势,上覆水重金属含量上升。间隙水重金属释放量与风速呈对数关系,Ni、Cd释放量分别为39.55 ng（小风）/77.91 ng（中风）/110.04 ng（大风）,以及1.10 ng（小风）/1.81 ng（中风）/2.80 ng（大风）。

英文摘要：

Submerged plants can effectively change the flow conditions and inhibit the sediment resuspension. In this study,surface sediments are subjected to resuspension under 3 different wind forces using a pneumatic annular flume. There are strong（8.78 m/s）, medium wind（5.95 m/s） and light wind（3.21 m/s）, respectively. The flow velocities at different wind speeds are measured by Acoustic Doppler Velocimeter（ADV）, and the flow velocities increase with wind speed obviously. The vertical distribution of flow velocity shows a ‘S＇-type curve in the vegetation flume. Concentrations of SPM（Suspended Particulate Matter） in overlying water increase with wind speed during the experiment, while decrease significantly with the shunt effect of vegetation. Based on the analysis of wind speed and the reduction of suspension rate, the quantitative relationship is obtained（ W =0.2194 ln（v）-0.2445）. Concentrations of heavy metals（Ni, Cd） in water column, pore water and sediment are measured by ICP-MS. The heavy metals in overlying water increased with wind speed. The content of heavy metals in pore water and sediments shows a downward trend. A logarithmic relationship is found between wind speed and release amount of heavy metals in pore water. The release amount of Ni and Cd are 39.55 ng（light wind） / 77.91 ng（medium wind） / 110.04 ng（strong wind） and 1.10 ng（light wind） / 1.81 ng（medium wind） / 2.80 ng（strong wind）, respectively.