根据2011年5月~2012年2月春、夏、秋、冬4个航次东海海域的调查资料,分析了东海典型断面 Chl a的分布特征、季节变化及其影响因素。结果表明: (1)东海海域Chl a的平面分布呈现出由近岸向远海递减的趋势,高值区相对集中在西部近岸海域,低浓度区域分布在东部较为开阔的远海海域。水动力条件、陆源径流的输入以及气候变化等因素是形成这种分布格局的主要原因。(2)Chl a的垂直分布受季节影响较大,春、夏两季变化幅度较秋、冬季大。(3)在季节变化上呈春季> 夏季> 秋季> 冬季的规律。(4)相关性分析表明,调查海域Chl a 与水温的关系在夏季较为显著;与盐度的相关性趋势并不明显,与DO 则在春季有着良好的相关性;与营养盐在春季呈显著正相关,说明营养盐是影响Chl a 分布的主导因子。
英文摘要:
Based on the data of 4 seasonal cruises in the East China Sea from May. 2011 to Feb. 2012, this paper posed an analysis on distributions, seasonal variations and influencing factors of Chl a. Results indicated that (1) : The horizontal distributions of Chl a concentration in the East China Sea decreased from the offshore to the open ocean with its higher values in the western coastal area and the lower in the eastern vast area mainly due to hydrodynamic conditions, inland runoff and climate change, etc. (2) : The fluctuation of vertical distributions of Chl a was strongly affected by seasonal variation with spring and summer much more considerably than that in autumn and winer. (3) : The degree of the content of Chl a in terms of seasonal variations ranged from spring, summer to autumn and winter. (4) Correlative analysis implied that there had been a good linear correlation between SST and Chl a in summer with that the same between DO and Chl a in spring,while the relation between salinity and Chl a was insignificant. DIN correlated to Chl a with various degrees among the 4 cruises, of which the most significant in spring,which can be inferred that nutrients were the dominant factor of the distributions of Chl a.