摘要
在一次风速12m/s的强风浪过程中及在连续多天弱风浪之后,对太湖梅梁湾一浅水区营养盐、悬浮物等的垂向分布进行了观测和分析。结果表明,在水底沉积物约20cm的情况下,强风浪期间与弱风浪期间相比,湖水中悬浮物浓度提高了10倍,总磷浓度提高了3 6倍。而强风浪期间与弱风浪期间的水体溶解性总磷(DTP)、溶解性活性磷(SRP)的浓度无显著差异。说明尽管强风浪过程引起沉积物大量悬浮,水体悬浮颗粒态营养盐显著增高,但是由于悬浮过程营养盐释放与沉降机制作用十分复杂,活性营养盐的浓度未必能提高。无论强风浪还是弱风浪期间,水体的表层至水土界面上50cm层的悬浮物浓度、营养盐浓度没有明显的分层现象,但明显低于水土界面上50cm内的悬浮物浓度和总磷浓度。无论是强风浪期间还是弱风浪期间,表层到底层水体SRP浓度无显著差异。
The vertical distribution of total phosphorus (TP), the dissolved total phosphorus (DTP), the soluble reactive phosphorus (SRP), the suspended solid (SS) and its loss on ignition (LOI) in Taihu lake, a large, shallow, eutrophic lake, was observed in a strong wind course (with the wind speed of 12 m/s) and a light breeze course (with the wind speed of (3 m/s)). The water depth of the observed site was 1.9?m. The concentrations of TP, DTP, SRP and SS at 10, 90, 140, and 190?cm below the water surface were monitored. The water-column mean concentration of SS in strong wind period was 468.8?mg/L±302.1?mg/L, which is 10 times higher than that in light breeze period, and the concentration of TP was 0.296?mg/L±0.081?mg/L, which is 3.6 times higher than that in light breeze period. However, the difference of the concentrations of DTP and SRP between strong wind period and light breeze period was insignificant. Additionally, both in the strong wind period and in the light breeze period, concentrations of SS and TP were insignificantly different among those in the upper three layers, and lower than those in the bottom layer. However, the concentrations of SRP were insignificantly different in the whole water column. The results indicate that, wind-induced wave not only cause the drastic sediment resuspension and the nutrient releasing, but also result in the absorption of dissolved reactive phosphorus. The sediment resuspension may not increase, but decrease the amount of the bio-available phosphorus in the water column.
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2004年第6期775-780,共6页
Advances in Water Science
基金
国家自然科学基金资助项目(40203007
40071019)
中国科学院知识创新工程重大项目(KZCX1 SW 12)~~
关键词
风浪
浅水湖泊
水动力
磷
悬浮物
太湖
shallow lake
hydrodynamics
phosphorus
resuspension
Taihu lake
