摘要
采用Y型旋浆式沉积物再悬浮装置研究了不同风速下太湖水生植被区沉积物的再悬浮和沉降过程.结果表明,中、小风过程中,随悬浮物浓度的增大,水体氨氮和磷酸盐浓度均显著增加,最大通量分别为0.063g/m2,4.28mg/m2.大风条件下,水体氨氮浓度出现减小趋势,最大通量为-0.027g/m2;磷酸盐浓度的增量相对于小风较小,最大释放量为1.52mg/m2.沉降阶段的最初2h是水体悬浮物浓度恢复的主要阶段,悬浮物浓度平均下降约46%.沉降8h之后,水体悬浮物及营养盐浓度基本恢复至风浪前初始水平,3种风速的氨氮和磷酸根磷的最大释放量仅为0.030g/m2,0.90mg/m2.与藻型湖区营养盐动态负荷结果相比,草型湖区的水体营养盐动态负荷变化相对较小.
A new Y-shape apparatus, which simulated hydrodynamic condition in situ driven by wind and wave, was adopted to study sediment re, suspension and settlement process in macrophytes dominated lake areas in Lake Taihu. Total suspended sediment （Tss） increased in light wind （3.2m/s） and moderate.wind（5.1m/s） processes until steady state, the contents of ammonia and phosphate increased correspondingly with the max flux of 0.063 g/m^2 and 4.28 mg/m^2 respectively. In strong wind （8.7m/s） process, little changes of ammonia and phosphate content appeared, with the max flux of -0.027 g/m^2 and 1.52 mg/m^2 respectively. Tss decreased sharply in initial 2 h of settlement process, only 46% of initial content. After settlement for 8 h, the contents of SS, ammonia nitrogen and phosphorus under each wind condition were close to initial contents before winds process, and the max flux of ammonia and phosphorus was 0.030 g/m^2 and 0.90 mg/m^2 respectively. Compared to algae dominated lake zones, less variations of nutrients loading were detected in grass type Lake.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2008年第1期33-38,共6页
China Environmental Science
基金
国家自然科学基金资助项目(40730528,20577053,40501064,40601087)
关键词
沉积物再悬浮
Y型装置
沉降
营养盐
水生植物
太湖
sediment resuspension
Y-shape apparatus
sedimentation
nutrients
aquatic macrophytes
Lake Taihu
