| 摘要: |
| 底泥疏浚的效果至今仍存在很大争议, 其中之一是疏浚后所产生的环境效果有可能偏离人们的期望, 疏浚能够有效的削减沉积物中营养物、重金属和持久性有机物等污染物含量, 但疏浚过程中会引起污染物向水体释放, 疏浚后的界面过程有可能对疏浚效果产生较大影响, 底泥疏浚对水体富营养化的控制有成功的经验也有失败的教训, 不同的湖泊疏浚后对营养盐释放的控制效果不同.底泥疏浚往往对底栖生物产生危害, 具体表现为种类、丰富度与生物量的减少, 群落结构发生变化, 多样性降低;疏浚后微生物胞外酶活性降低, 底泥疏浚对沉积物代谢功能存在显著影响, 底栖生物和酶活性的恢复需要长期的过程.底泥疏浚对湖泊水污染控制具有时效性, 疏浚方式、疏浚深度与疏浚时令是疏浚工程应关注的问题. |
| 关键词: 底泥疏浚 效果 环境效应 污染物 底柄生物 |
| DOI：10.18307/2007.0101 |
| 分类号: |
| 基金项目:国家自然科学基金(20577053);国家高技术研究发展计划(200560101005);中国科学院知识创新项目(KZCX3-SW-348)共同资助. |
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| Advance in the study on the effectiveness and environmental impact of sediment dredging |
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ZHONG Jicheng1,2, FAN Chengxin1
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1.Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P.R.China;2.Graduate School of Chinese Academy of Sciences, Beijing 100039, P.R.China
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| Abstract: |
| The effectiveness of sediment dredging is still strongly debated up to now, and the environmental effects resulting from sediment dredging may be not ideal as the people have expected.Sediment dredging can effectively lower the contents of nutrient, heavy metals and persistent organic pollutants in sediment, but resuspension of sediment during dredging will induce the release of pollutants from sediment to the water column.In addition, the interface processes will exert great influence on the dredging effect.There are successes and lessons for the control of eutrophication, different effects appear for the control of the release of nutrients in different lakes.Sediments dredging has dverse effects on benthos, e.g.decreases of taxa numbers, abundance and biomass.Moreover, there could be a change of community composition and a fall in the diversity.Extracellular enzymes activities could be depressed significantly.As a result, sediment dredging has profound impact on the hydrolytic activities of sediments.It is a long term for the recovery of benthos and enzymes activities.The effectiveness of sediment dredging on water pollution control is usually time-limited.The methods of dredging, the depth of dredging, as well as the season when dredging is carried out should be concerned in dredging program implementation. |
| Key words: Sediment dredging effectiveness environmental effects pollutants benthos |
