2015年东海区营养盐的分布变化特征

Seasonal variations of distribution characteristics of nutrients in the East China Sea in 2015

利用2015年春(5月)、夏(8月)、秋(11月)、冬(2月)4个季节在东海区标准断面调查所得的资料,通过对5项营养盐综合分析研究了营养盐表层、10 m层、底层的含量变化及其随季节的分布特征,并对其变化规律和影响因素等进行探讨分析。研究表明:无机氮、磷酸盐及硅酸盐含量均值最高都在底层,几乎都呈现由表层至底层逐渐升高趋势。2015年东海区营养盐分布具有明显的季节变化,对于磷酸盐和无机氮的含量表现为冬季>秋季>夏季>春季,硅酸盐的含量表现为夏季>冬季>秋季>春季。东海营养盐主要来源于长江冲淡水,往往受长江冲淡水和台湾暖流同时控制,浓度大体呈现自西向东递减的变化趋势。

A survey of seasonal distribution characteristics of nutrients in the East China Sea standard sections was carried out in 2015. Based on the survey data in four seasons from East China Sea standard sections （mean values in May, August, November and February represent values in spring, summer, autumn and winter, respectively）, seasonal distribution characteristics and variations in contents of five nutrients at the surface, at the depth of 10 m and at the bottom were comprehensively analyzed. The main impact factors were also discussed in this paper. The results show that the highest inorganic nitrogen, phosphate and silicate contents occurred at the bottom of the content, almost with an increasing trend from surface to the bottom. In the East China Sea in 2015, the distribution of nutrients has obvious seasonal variations, and phosphate content and inorganic nitrogen content are higher in autumn and winter than those in spring and summer. Silicate content is higher in summer and winter than that in autumn and spring. The main source of nutrients in the East China Sea is the Changjiang river diluted water, and the Taiwan Warm Current also carries a portion of nutrients into the East China Sea. The combined effect of the Changjiang fiver diluted water and Taiwan Warm Current makes the nutrients concentration in East China Sea decrease from west to east.