2010年春秋季长江口南部硅藻种类组成和密度的时空变化  

Species composition and diatom seasonal successions in the south of Changjiang Estuary and its adjacent waters in spring and autumn of 2010

作　　者：李静[1] 陈长平[1] 梁君荣[1] 刘昱涵 刘广发[1] 高亚辉[1] 

机构地区：[1]厦门大学生命科学学院,滨海湿地生态系统教育部重点实验室,福建厦门361005

出　　处：《应用海洋学学报》2015年第3期372-387,共16页Journal of Applied Oceanography

基　　金：国家“973”资助项目(2010CB428704);国家自然科学基金资助项目(41276128,41276100)

摘　　要：2010年4、5及10月,在长江口南部及其邻近海域典型赤潮高发区分别进行拖网和水样采集,获得浮游植物样品180个,进行硅藻种类组成与数量分析.3个航次分别鉴定出硅藻43属134种、37属126种及45属155种;3个航次共有的属有29个,分别占各航次硅藻属总数的67.44%、78.38%和64.44%.硅藻种类多样性4、10月高于5月.3个航次的种类最多硅藻均为圆筛藻(Coscinodiscus spp.).4、5月和10月圆筛藻属的种类数目及其所占比例分别为22种(16.30%)、30种(23.62%)及26种(16.67%).在这3个航次调查中,圆筛藻种类多样性随季节变化表现出低-高-低的特征,而硅藻种类多样性随季节变化刚好相反,呈现高-低-高的变化,两者具有一定的负相关性.硅藻细胞密度水平分布和垂直分布的的变化趋势为春季4、5月高于秋季10月.骨条藻(Skeletonema spp.)是4、5月的数量优势种,10月没有明显优势的硅藻.硅藻数量分布的季节性变化和春季藻类赤潮、长江冲淡水通量及其流向的季节性变化有关.长江口南部及其邻近海域硅藻高值区表现出从近岸向外海降低的趋势.Analyses of the diatom composition and abundance were done on 180 net and water samples collected from frequent red-tide occurring waters in the south of Changjiang Estuary and its adjacent waters in April,May and October,2010. The diatoms recorded belong to 43 genus and 134 species,37 genus and 126 species and 45 genus and 155 species,from 3 cruises,respectively. There were 29 common species,occupying 67. 44%,78. 38% and64. 44% of the total species in each cruise. Coscinodiscus was the most diversified group of all 3 cruises. The species number and percentage of the total diatom species were 22 species in April（ 16. 30%）,30 species in May（ 23. 62%） and 26 species in October（ 16. 67%）. Coscinodiscus diversity showed a pattern of ＂low-high-low＂with seasonal alterlations while the diversity of diatoms showed the opposite,characterized by a pattern of ＂HighLow-High＂. These 2 indexes showed a negative correlation. The vertical distribution and horizontal distribution of diatom density showed that they were higher in April and May of spring than in October of autumn. Dominate diatoms in the first and second cruises were skeletonema spp.,while they didn＇t dominate in the third cruise. Densitydistribution of diatoms was related to spring＇s algae bloom,the diluted water flux of Changjiang River and current direction. Diatom density showed a decrease tendency from offshore to open waters in the South of Changjiang Estuary and its adjacent waters.

关 键 词：海洋生物学 硅藻 种类 演替 赤潮 海流 长江口南部 

分 类 号：P735[天文地球—海洋生物学]