| 摘要: |
| 2014年冬季对西太平洋雅浦区Y3海山及其邻近大洋海域不同粒径浮游植物叶绿素a浓度进行了现场观测，同时结合温度、盐度、营养盐数据，分析了Y3海山区总叶绿素a浓度分布情况，不同粒级浮游植物对总叶绿素a浓度的贡献率及其与环境因子的关系，并与热带西太平洋大洋区（DY断面）进行了比较。结果表明：Y3海山A、B断面与DY断面水体平均叶绿素a浓度相差不大，分别为0.057、0.054和0.051mg/m3，A、B和DY三个断面各水层（0、30、75、100、150和200m）叶绿素a浓度变化范围分别为0.009—0.205、0.005—0.236和0.007—0.229mg/m3。不同粒级浮游植物的叶绿素a占总叶绿素a的比例从大到小依次为微微型浮游植物、微型浮游植物和小型浮游植物，三者在各断面的比例分别为A断面：59.97%，25.39%，14.64%；B断面：50.87%，30.70%，18.43%；DY断面：55.87%，29.87%，14.26%。微微型浮游植物在整个调查区域为优势类群，在A、B和DY三个断面的平均浓度分别为0.025、0.026和0.029mg/m3。各站位均有次表层叶绿素a浓度最高值现象，其中Y3海山区西南部和东南部为叶绿素a浓度高值区。洋流、温度和营养盐均对叶绿素a浓度分布有一定的影响。本研究发现海山经典假说不适用于2014年冬季的Y3海山区。 |
| 关键词: 西太平洋海山 浮游植物叶绿素a 粒级结构 环境因子 |
| DOI：10.11693/hyhz20160100020 |
| 分类号: |
| 基金项目:中国科学院海洋先导科技专项（A类），XDA11030204号；国家重点基础研究发展计划（973）资助项目，2014CB441504号。 |
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| CHLOROPHYLL A CONCENTRATION AND SIZE STRUCTURE OF PHYTOPLANKTON AT YARP Y3 SEAMOUNT IN TROPICAL WEST PACIFIC IN WINTER 2014 |
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ZHANG Wen-Jing1,2, SUN Xiao-Xia1,3, CHEN Yun-Yan1,2, LI Jun-Lei1,2, DU Juan1
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1.Jiaozhou Bay Marine Ecosystem Research Station, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;2.University of Chinese Academy of Sciences, Beijing 100049, China;3.Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
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| Abstract: |
| The size-fractionated chlorophyll a concentration (Chl a), temperature, salinity, and nutrients at Seamount Y3 near Yarp Trench in the western Pacific in winter 2014 were investigated. In terms of Chl a, size-fractionated contribution to the total Chl a, and correlation between Chl a and ambient factors, Seamount Y3 (Transects A and B) was compared with the tropical western Pacific (Transect DY). The results indicate that there were no obvious differences among Transects A, B and DY in average Chl a (0.057, 0.054, and 0.051 mg/m3, respectively), and in Chl a range in 0, 30, 75, 100, 150, and 200 m depth (0.009—0.205, 0.005—0.236, and 0.007—0.229 mg/m3, respectively). The size structures in the 3 transects were similar. Specifically, the proportion of Chl a from micro-phytoplankton, nano-phytoplankton, to pico-phytoplankton was in a descend order, i.e., 59.97%, 25.39%, 14.64% for Transect A; 50.87%, 30.70%, 18.43% for Transect B; and 55.87%, 29.87%, 14.26% for Transect DY. The average pico-phytoplankton Chl a was 0.025, 0.026, and 0.029 mg/m3, respectively. Phytoplankton was dominant, a subsurface Chl a maximum was common in all the study region, and higher Chl a was recorded to the southwest and southeast of Y3 Seamount. The Chl a distribution was affected by currents, temperature, and nutrients. The above data show that traditional explanation on Chl a in seamount does not fit for the case of Seamount Y3 in winter 2014. |
| Key words: Western Pacific seamount phytoplankton Chl a size structure ambient factor |
