黄海近岸溶解活性态铁定点连续分析研究

Continuous analysis of dissolved reactive iron at fixed-point of Yellow Sea coast

铁(Fe)是海洋浮游植物生长必需的微量元素,也是影响海洋初级生产力的关键因素。溶解活性态铁(DR_(Fe))是溶解态Fe的主要组成之一,与海洋生物体的吸收密切相关。本文通过对黄海近岸海水30天定点连续分析监测,研究了黄海近岸海水中DR_(Fe)在高、低潮时的浓度变化特征,分析监测了潮汐作用对DR_(Fe)的影响,并探讨了DR_(Fe)与海水理化参数间的关系。研究表明:高潮时DR_(Fe)浓度略高于低潮,最大浓度差为2.32 nmol/L,最小浓度差为0.44 nmol/L;DR_(Fe)浓度月变化差异不大,其范围为4.06~8.34 nmol/L,平均浓度为5.70 nmol/L;5月初,DR_(Fe)浓度较高,随后逐渐下降;海水温度升高会促进浮游植物生长,致使Chl a含量增加,同时加速DR_(Fe)的消耗。

Iron(Fe)is an essential micronutrient for the growth of marine phytoplankton and a key factor to affect marine primary productivity.Dissolved reactive iron(DR_(Fe)),one of the main components of dissolved Fe,is closely related to the absorption of marine organisms.In this paper,the variation characteristics of DR_(Fe) concentration at high tide and low tide were studied by continuous monitoring at Yellow Sea coast for 30 days.The effect of tidal action on DR_(Fe) concentration was analyzed,and the relationship between DR_(Fe) concentration and physicochemical parameters of seawater was further discussed.This study showed that the DR_(Fe) concentration at high tide was slightly higher than that at low tide,with a maximum concentration difference of 2.32 nmol/L and a minimum concentration difference of 0.44 nmol/L.The monthly variation of DR_(Fe) concentration was not significant in May,ranging from 4.06 to 8.34 nmol/L,with an average concentration of 5.70 nmol/L.DR_(Fe) concentrations were higher at the beginning of the month and then gradually declined.The increase of seawater temperature will promote the growth of phytoplankton and increase of chlorophyll a content,which will accelerate the consumption of DR_(Fe).