渤黄海营养盐结构及其潜在限制作用的时空分布

根据2006-2007年4个季节的现场调查资料,分析探讨了渤海和黄海营养盐结构分布变化特征及其对浮游植物生长的潜在的限制状况.结果表明,渤黄海水体 Si/N/P 比值均偏离 Redfield 比值,季节变化明显;春夏冬季 N/P和 Si/P比值由近岸向远岸海域递减,高值区主要分布在黄河口、鸭绿江口及苏北近岸,秋季上层水体N/P和Si/P比值的分布趋势有所不同,高值区主要分布在南黄海的中部海域.受陆源输入的影响,近岸特别是河口区 N/P和 Si/P比值均较高,温跃层的生消变化和生物活动调控着黄海中部海域营养盐结构的变化.渤黄海浮游植物生长主要受P的潜在限制,部分季节受N、Si的潜在限制;营养盐限制状况存在着明显的时空变化及不同营养盐的同时或交替限制的现象.

Temporal and spatial distributions of nutrient structure and potential nutrient limitation in the Bohai Sea and the Yellow Sea

Based on the seasonal field observation during 2006 -2007, distributions of nutrient structure and their potential limitation on phytoplankton growth in the Bohai Sea and the Yellow Sea were discussed. The results showed that ratios of N/P, Si/N and Si/P varied greatly in different seasons, and deviated from Redfield ratios. The ratios of N/P and Si/P decreased from inshore to offshore area in spring, summer and winter, while showed the different pattern in the upper water in autumn, higher values of N/P and Si/P ratios were observed in the middle of the southern Yellow Sea. Due to the influence of terrestrial runoff, the inshore waters especially at the estuary area presented very high N/P and Si/P ratios. Changes of thermocline and biological activities controlled the nutrient structure in the central area of the Yellow Sea. The primary production might be limited by phosphate in a considerable portion of the Bohai Sea and the Yellow Sea. The potential nutrient limitation showed temporal and spatial variations, and the phytoplankton were usually limited by single or multiple nutrients at the same time or subsequently.