草/藻混合分布型湖泊沉积物释放风险与治理对策:以太湖为例  

Risk of sediment release from grass/algae mixed lakes and its control countermeasures:A case study of the Taihu Lake

作　　者：刘伟 胡保安 程瑾 黄佳音 张勇 LIU Wei;HU Baoan;CHENG Jin;HUANG Jiayin;ZHANG Yong(China Communications(Tianjin)Ecological and Environmental Protection Design and Research Institute Co.,Ltd.Tianjin 300042,China)

机构地区：[1]中交(天津)生态环保设计研究院有限公司,天津300042

出　　处：《环境工程》2025年第2期157-166,共10页Environmental Engineering

摘　　要：研究太湖不同湖区底泥污染评价与氮磷释放风险,以评估太湖沉积物氮磷营养盐交换通量对上覆水水质产生的重要影响。结果显示:太湖底泥中ρ(TN)在1.85~3.57 g/kg,污染综合指数评价处于重度污染水平;ρ(TP)介于0.15~1.40 g/kg,通过污染综合指数评价,各湖区沉积物中草型湖区(东太湖、南太湖)处于清洁水平。不同湖区表层沉积物孔隙水中NH_(4)^(+)-N、溶解态磷(TDP)浓度远高于上覆水。藻型湖区梅梁湾NH_(4)^(+)-N释放速率为125.86 mg/(m^(2)·d),TDP释放速率为4.88 mg/(m^(2)·d);草型湖区东太湖NH_(4)^(+)-N释放速率为42.46 mg/(m^(2)·d),TDP释放速率为3.93 mg/(m^(2)·d)。藻型湖区沉积物TN、TP污染高于草型湖区,藻型湖区表层沉积物-水界面NH_(4)^(+)-N、TDP释放速率高于草型湖区,氮磷内源释放风险较大,是湖泊富营养化主要原因。可通过外源污染控制结合原位覆盖技术、生态系统修复、曝气复氧、底泥环保疏浚以及底泥钝化等内源治理多种方式,降低湖内营养负荷,提升太湖对水体污染物的净化作用。In this paper,sediment pollution assessment and nitrogen and phosphorus release risk study in different areas of the Taihu Lake were conducted to assess the impact of nitrogen and phosphorus nutrient exchange flux in the Taihu Lake sediments on the overlying water quality.The results showed that the contents of TN(total nitrogen)and TP(total phosphorus)in the sediment of the Taihu Lake were high,especially the TN content was between 1.85 g/kg and 3.57 g/kg.According to the comprehensive pollution index evaluation,it was at the level of heavy pollution.TP content was between 0.15 g/kg and 1.40 g/kg.According to the comprehensive pollution index assessment,the sediment of the grass type lake areas(Eastern and Southern Taihu Lake)was at a clean level.The concentrations of NH_(4)^(+)-N and dissolved phosphorus(TDP)in pore water of surface sediments were much higher than those in the overlying water in different lake areas.The release rates of NH_(4)^(+)-N and TDP in Meiliang Bay of the algal lake area were 125.86 mg/(m^(2)·d)and 4.88 mg/(m^(2)·d),respectively.The NH_(4)^(+)-N release rate of Eastern Taihu Lake in the grass-type lake area was 42.46 mg/(m^(2)·d),and the TDP release rate was 3.93 mg/(m^(2)·d).The release rates of NH_(4)^(+)-N and TDP at the surface sediment water interface in the algae-type lake area were higher than those in the grass-type lake area.It could be seen that each lake area of the Taihu Lake had a great risk of endogenous release of nitrogen and phosphorus,of which the risk of endogenous release in the algae-type lake area was higher than that in the grass-type lake area.The endogenous release of nitrogen and phosphorus from moderately and severely polluted sediments in the Taihu Lake area was the main reason for eutrophication.We could comprehensively reduce the nutrient load in the lake and enhance the purification effect of the Taihu Lake on water pollutants through external pollution control measures,combined with in-situ coverage technology,ecosystem restoration,aeration and reaera

关 键 词：草/藻型湖区 沉积物 污染评价 释放风险 富营养化 内源治理对策 

分 类 号：X524[环境科学与工程—环境工程]