| 引用本文: | 陈旭,羊向东,刘倩,刘恩峰.巢湖近代沉积硅藻种群变化与富营养化过程重建.湖泊科学,2010,22(4):607-615. DOI:10.18307/2010.0419 |
| CHEN Xu,YANG Xiangdong,LIU Qian,LIU Enfeng.Sedimentary diatom flora changes and eutrophication reconstruction for the last 200 years in Lake Chaohu. J. Lake Sci.2010,22(4):607-615. DOI:10.18307/2010.0419 |
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| 摘要: |
| 根据巢湖西部湖心40cm长的沉积柱放射性核素定年和化石硅藻分析,结合长江中下游湖泊硅藻-总磷转换函数模型,重建了其过去200年来硅藻组合演替与湖水总磷浓度变化的历史.研究结果表明,巢湖硅藻经历了从Aulacoseira granulata优势组合(1826-1978年)向耐营养种Cyclostephanos dubius优势组合(1978年以来)变化的两个重要阶段.1978年前,水体总磷浓度在60-75μg/L之间;此后迅速增高(80-100μg/L),为明显的营养富集时期;至2000年以来总磷浓度进一步上升(>110μg/L),硅藻组合以Cyclostephanos dubius占绝对优势.硅藻数据的最大变率与总磷浓度的关系反映硅藻生态主要响应于营养富集的变化,但历史时期水动力条件对硅藻种群也有一定影响.20世纪70年代以来,工农业以及生活污水排放是硅藻种群转变和富营养化发生的主要根源,而巢湖闸的建立引起的水文条件的改变也是水体营养富集的诱因.21世纪开始富营养化进一步加重可能与生活污水排放、营养内负荷释放以及增温有关. |
| 关键词: 硅藻组合 总磷重建 富营养化 水动力条件 巢湖 |
| DOI：10.18307/2010.0419 |
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| 基金项目:国家水体污染控制与治理科技重大专项课题项目(2008ZX07103-003);中国科学院知识创新工程重要方向项目(KZCX2-YW-319)资助 |
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| Sedimentary diatom flora changes and eutrophication reconstruction for the last 200 years in Lake Chaohu |
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CHEN Xu1,2, YANG Xiangdong1, LIU Qian1,2,3, LIU Enfeng1
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1.State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China;2.Graduate University of Chinese Academy of Sciences, Beijing 100049, P. R. China;3.College of Ocean, Hohai University, Nanjing 210098, P. R. China
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| Abstract: |
| The evolution of diatom flora and the dynamic process of total phosphorus concentration (TP),were reconstructed for the last 200 years in Lake Chaohu based on the sedimentary diatom analysis and radionuclide dating for a 40cm long core from the centre of West Lake Chaohu, combining with an established diatom-TP transfer function in Yangtze floodplain Likes. The results showed that the diatom flora experienced two important stages from the Aulacoseira granulata predominant assemblages(1826-1978AD) to the Cyclostephanos dubius predominant flora (since 1978AD). Before 1978AD TP remained around GO一75wg/L and afterward increased rapidly to 80一100μg/L, which reflected an obvious nutrient accumulation. Since 2000AD TP had increased to 110μg/L and C. dubius became dominant spies. The relationship between main changes of diatom flora and TP reflected that di-atom flora changes mostly attributed to the nutrient enrichment. However, hydrodynamic conditions also had certain influence on diatom composition in the historical period. Since 1970s industrial, agricultural and domestic sewage had become major cause of the eutrophication and diatom flora changes, while shift of hydrodynamic conditions resulted from the establishment of the Chaohu Gate was also an incentive of nutrient accumulation. From the beginning of the 21st Century the deterioration of eutrophication may be related to domestic sewage discharges, internal nutrient releases and the global warning. |
| Key words: Diatom assemblages total phosphorus hydrodynamic conditions Lake Chaohu |
