摘要
为探究边缘海区域由陆架到深海盆脂类的分布模式及其指示的生物源的空间变化特征,对采集于南海4个不同水深断面的表层沉积物脂肪酸进行了系统研究.从表层沉积物中检出丰富的脂肪酸,包括直链饱和脂肪酸、直链不饱和脂肪酸和支链脂肪酸等.其中,高碳数直链脂肪酸(≥C20)主要来源于陆源高等植物的输入,低碳数直链脂肪酸主要来源于藻类的贡献,低碳数支链(包括异构和反异构)脂肪酸主要来源于细菌贡献.高碳数脂肪酸指示的高等植物输入,在南海沿岸区的高值与河流的输入有关,而在深海盆的高值可能与洋流、风尘输入等有关.低碳数支链脂肪酸指示的细菌分布在南海北部沿岸表现出高值,在深海盆表现出较低的分布模式.低碳数直链脂肪酸表征的浮游植物的贡献在南海北部表现出高值,在深海盆局部区域也表现出高值分布.细菌和浮游植物在南海北部表现出的高值,可能与丰富的营养盐条件有关.而浮游植物在深海盆的分布模式,可能受到洋流以及其他输入的影响.
To investigate the spatial distribution of lipid biomarkers from offshore to deep basin in the marginal sea, fatty acids （FAs） in surface sediments collected from different water depths across four different transects were studied. Abundant FAs, including saturated and unsaturated normal FAs, as well as saturated iso- and anteiso-FAs, were detected. The FAs are dominated by short-chain saturated FAs, showing a mono-model distribution. The long-chain FAs, showing an even-over-odd distribution, are mainly derived from terrestrial higher plants, and short-chain normal FAs are derived from marine phytoplankton, while saturated iso- and anteiso-FAs are mainly contributed by marine bacteria. The long-chain FAs derived from the higher plants show the higher concentration in the coastal area which is contributed by the fluvial input, as well as in the deep basin which may be resulted from the ocean current, and likely, the aeolian dust input. Branched short-chain FAs indicate that the bacteria have great contribution in the coastal area but not in the deep basin. Short-chain normal FAs indicate that the phyto-plankton relative abundance is greal in northeast South China Sea and the deep basin. The higher contribution of both bacteria and phytoplankton in the coastal area is possibly related to higher nutrient input, while the higher phytoplankton distribution in the deep basin may be influenced by the ocean current or other input.
作者
杨义
郝宇昕
阮小燕
李学杰
姚永坚
杨楚鹏
Yang Yi;Hao Yuxin;Ruan Xiaoyan;Li Xuejie;Yao Yongjian;yang Chupeng(State Key Laboratory of Biogeology and Environmental Geology,School of Earth Sciences,China University of Geosciences,Wuhan 430074,China;Key Laboratory of Tectonics and Petroleum Resources,Ministry of Education,China University of Geosciences,Wuhan 430074,China;Guangzhou Marine Geological Survey,Ministry of Land and Resources,Guangzhou 510075,China)
出处
《地球科学》
EI
CAS
CSCD
北大核心
2018年第11期4027-4035,共9页
Earth Science
基金
国家重点研发计划项目(No.2016YFA0601100)
自然资源部广州海洋地质调查局项目(No.GZH201500202)
关键词
南海
脂肪酸
陆源输入
浮游植物生产力
细菌
Soutb China Sea
fatty acid
terrestrial input
phytoplankton production
bacteria.
