东海不同底质类型海域春季悬浮体通量及影响因素

摘要

Observations of suspended sediment and hydrographic investigation are carried out in two representative areas, nominally the mud ar ea southwest of Cheju Island and the sand area on the middle shelf of the East C hina Sea in April 1994. Vertical distribution of residual and suspended sediment flux in two areas are calculated and compared to represent transport of suspend ed sediment in two areas. The results show that suspended sediment flux and vert ical distribution of TSM in the mud area and in the sand area have markedly diff erent characteristics. The differences can be explained by the effect of four fa ctors: surface sediment type, hydrodynamics, sediment source, productivity and a ssociated biogeochemical process. These factors affect the two areas differently and cause the difference of suspended sediment flux in two areas. The mud area has relatively large flux and suspended sediment in upper water column (above 4 0m in depth) is transported southeastward; lower water column (deeper than 40m i n depth) in the area have a larger suspended sediment flux than the uppe r water column, and suspended sediment are transported northeastward. Suspended sediment flux in the sand area is less than that in the mud area, and suspended sediment in whole water column is transported northeastward.%利用1994年4月在东海陆架不同底质类型海域即泥 质区和砂质区的水文和泥沙观测资料，分析和计算了两个站的悬浮体含量的分布、余流分布 和悬浮体通量，以代表两个局部海域悬浮体含量分布和输送的特征。结果表明，在底质类型 、生物活动、水动力环境和悬浮体物源各因素的影响下，两个海域的悬浮体通量和悬浮体含 量垂直分布各有其特征，是东海悬浮体输送和垂直分布的两种典型类型。111站周围海域的 悬浮体通量较大，上、中层水体(0-40m)中的悬浮体向东南方向输送，下层和底层的悬浮体 向东北方向输送，且下层和底层的通量大于中上层；砂质区的悬浮体通量相对较小，且从表 层到底层均向东北方向运移。