| 摘要: |
| 根据1959 年和2002 年在长江口海域28°00'—32°00'N, 122°00'—123°30'E 海域4 个季节8个航次海洋调查资料, 分析长江口夜光藻丰度的平面分布和季节变化特征。并结合同步的温度资料进行曲线拟合, 构造数学模型, 计算最适温度。结合夜光藻分布特征、生态类群, 比较不同年间夜光藻丰度变化趋势, 分析长江口富营养化趋势对夜光藻丰度的影响。结果表明, 夜光藻出现率和平均丰度均表现为春季丰度极高而其它季节较低。例如春季长江口夜光藻的最高丰度可以达到48576.00ind/m3, 出现率为96.30%。该种在春季有明显的集群性, 其它季节聚集强度指标值较低。盐度是影响夜光藻的平面分布的主要因素。长江口夜光藻适温范围较窄。仅仅在15—20℃之间有较高的数量。通过曲线拟合计算, 其丰度和温度的函数关系符合Yield Density 模型。进一步通过极值计算得出, 夜光藻最适温度为17.53℃。在长江口, 夜光藻往往生活在在长江径流和外海水形成的河口锋水域。因而是暖温性近海种。近年来在春季, 长江口夜光藻数量明显增多, 夜光藻数量的年间变化特征可能与长江口富营养化相关。夜光藻赤潮的爆发就是长江口海域富营养化的结果之一。
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| 关键词: 夜光藻, 富营养化, 最适温度, 最适盐度, 长江口 |
| DOI：10.11693/hyhz200906019019 |
| 分类号: |
| 基金项目:国家自然科学基金重大研究计划, 90511005 号 |
附件 |
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| THE INTER-ANNUAL VARIATIONS IN NOCTILUCA SCINTILLANS ABUNDANCE AND EUTROPHICATION IN CHANGJIANG ESTUARY |
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XU Zhao-Li
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Key and Open Laboratory of Marine and Estuary Fisheries, Ministry of Agriculture of China, East China Sea Fisheries Research Institute, Chinese Academy of Fisheries Sciences
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| Abstract: |
| Data gathered in eight seasonal oceanographic investigations in the Changjiang (Yangtze River) estuary (28°00'—32°00'N, 122°00'—123°30'E) in 1959 and 2002 were used to study the temporal-spatial distribution of Noctiluca scintillans in the waters, with which the ecological groups were classified using mathematical modeling. The impact of environmental factors on the eutrophication and the relation between eutrophication and the abundance of the species were studied. Clear seasonal variations in the abundance and occurrence frequency of N. scintillans have been recognized: very high abundance (48576.00ind/m3) and occurrence frequency (96.30%) in spring and low in other seasons; they assembled in spring, but scattered in other seasons. Salinity was shown a critical factor in determining the distribution in the estuarine waters, so did temperature as it inhabited coastal temperate zone in a narrow range of 15—20℃, best around 17.53℃. Notably, the abundance in spring of the estuary has been increasing significantly in recent years, resulted from eutrophication and caused HAB. Therefore, the species can be used to estimate eutrophication status.
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| Key words: Noctiluca scintillans, Eutrophication, Optimal temperature, Optimal salinity, The Changjiang estuary |
