| 摘要: |
| 水体温度过高和磷浓度是影响枝角类Daphnia存活和繁殖的重要因子,因此本研究假设太湖夏秋季水体高温和磷浓度是引起Daphnia种群夏秋季消退的原因.通过夏秋季两次为期各15d的模拟实验,模拟高温和添加磷盐对太湖春季优势种同形溞Daphnia similis种群的影响,结果表明在高温和不添加磷盐的条件下,同形溞均有较高的种群增长率,证实夏秋季太湖水体高温和磷浓度不是限制Daphnia种群的因素,同时推测,鱼类的捕食作用和微囊藻水华对Daphnia种群的消退可能起作用. |
| 关键词: 溞 种群消退 高温 磷浓度 太湖 |
| DOI：10.18307/2010.0411 |
| 分类号: |
| 基金项目:国家自然科学基金项目(30600069);国家重点基础研究发展规划“973”项目(2008CB418104)资助 |
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| Preliminary analysis on population decline of Daphniain summer and autumn in Lake Taihu |
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LI Jing1,2, CHEN Feizhou1
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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
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| Abstract: |
| In Lake Taihu, Daphnia population dominated in the cladoceran community in winter and spring. However, the population disappeared in summer and autumn when it was replaced by the small-sized cladocerans. Theoretically, temperature and phosphorus concentration were two Limited factors for the Daphnia population. It is hypothesized that high temperature and phosphorus concentration were the reasons for the population decline of Daphnia in summer and autumn in Lake Taihu. The two experiments simulated summer and autumn separately were conducted. The results indicated that D. similis had relatively high increasing population rates under the simulating conditions, which proved that the high temperature and phosphorus concentration in summer and autumn in Lake Taihu were not the limit factors for the population decline of Daphnia. It was also presumed that the planktivorous fish predation and Microcystis bloom may be the reasons of the population decline of Daphnia in Lake Taihu. |
| Key words: Daphnia population decline high temperature phosphorus concentration Lake Taihu |
