太湖流域滆湖水体悬浮物分布特征及其影响因素

基于2018—2019年的周年调查，分析了滆湖总悬浮物（TSS）的时空分布特征、组成及其季节变化规律，并探讨了水体悬浮物的影响因素及其与氮、磷的关系.结果表明：（1） TSS浓度的年内变化范围在11.80~105.87 mg/L之间，平均浓度为41.87±18.09 mg/L.（2）滆湖水体TSS时空差异显著.空间上呈现高速公路以南湖区（B区）大于高速公路以北湖区（A区），沿岸高于湖心区的分布趋势；季节变化整体表现为：夏季 > 秋季 > 春季 > 冬季，且夏季显著高于其他季节.（3）滆湖水体中无机悬浮物（ISS）和有机悬浮物所占TSS的比例差异悬殊，分别为75.5%和24.5%，A区和B区均以ISS为主.（4）线性拟合表明，TSS与颗粒态氮、总磷和颗粒态磷具有极显著正相关关系；（5） TSS与叶绿素a浓度相关性极显著.综合结果分析，藻类暴发和泥沙再悬浮是影响滆湖水体悬浮物浓度的重要因素.

Characteristics and its influencing factors of suspended solids distribution in Lake Gehu, Taihu Basin

The spatial-temporal distribution characteristics, composition and its change rule of different seasons of total suspended solids (TSS) in Lake Gehu, were analyzed by annual investigation in 2018-2019. The key impacting factors of TSS and relationship between it and nitrogen, phosphorus were discussed. The results showed that the annual variation of TSS concentration ranged from 11.80 to 105.87 mg/L, and the average concentration was 41.87±18.09 mg/L. The temporal and spatial differences of TSS in Lake Gehu were significant. The spatial distribution trend of the lake area south of the highway (B area) was larger than that of the lake area north of the highway (A area), and the coastal area was higher than the central area. As a whole, the seasonal change was manifested as summer > autumn > spring > winter, and summer was significantly higher than other seasons. The proportions of inorganic suspended solids (ISS) and organic suspended solids (OSS) in TSS of the whole lake body were significantly different, with the value of 75.5% and 24.5%, respectively. Both area A and area B was dominated by ISS. Linear fitting showed that TSS had extremely significant positive correlation with particulate nitrogen, total phosphorus and particulate phosphorus. The correlation between TSS and chlorophyll-a was also significant. Based on the above analyses, algal blooms and sediment resuspension were important factors affecting the concentration of suspended solids in water.