發(fā)布時間：2018-10-26 09:58

【摘要】：于2013年3月和8月研究了長江口及其鄰近海域葉綠素a的分布特征,并對環(huán)境因子和長江沖淡水對浮游植物生物量分布的影響進行了探討。結(jié)果表明,葉綠素a濃度在豐水期較高,平均值為5.18μg/L,最高值達32.05μg/L,現(xiàn)場海水出現(xiàn)變色現(xiàn)象;與同期歷史資料對比分析,發(fā)現(xiàn)該海域葉綠素a濃度呈現(xiàn)出波動增長趨勢。豐水期與枯水期葉綠素a的相對高值區(qū)均位于沖淡水的中部,122.5°E~123°E之間;豐水期在調(diào)查海域出現(xiàn)溶解氧低值區(qū)與低氧區(qū),最低值僅為0.64 mg/L;發(fā)現(xiàn)低氧區(qū)出現(xiàn)位置北移、面積擴大和溶解氧最低值下降的趨勢。底層溶解氧低值區(qū)分布與表層葉綠素高值區(qū)大致吻合,表明低氧現(xiàn)象與表層浮游植物的生長和現(xiàn)存量密切相關(guān),在躍層存在的水體中表層浮游植物的大量繁殖易造成底層低氧區(qū)的出現(xiàn)。
[Abstract]:The distribution characteristics of chlorophyll a in Changjiang Estuary and its adjacent waters were studied in March and August 2013. The effects of environmental factors and diluted water on biomass distribution of phytoplankton were discussed. The results showed that the concentration of chlorophyll a was higher in the high water season, the average value was 5.18 渭 g / L, the highest value was 32.05 渭 g / L, and the discoloration of seawater was observed. Compared with the historical data of the same period, it was found that the concentration of chlorophyll a in this area showed a fluctuating trend. The relative high value of chlorophyll a in high and dry season is between 122.5 擄E and 123 擄E of diluted water, and the low value of dissolved oxygen and low oxygen is only 0. 64 mg/L; during high water period. It is found that the location of hypoxia region moves northward, the area expands and the minimum value of dissolved oxygen decreases. The distribution of the low value of dissolved oxygen in the bottom layer was approximately consistent with the high value of chlorophyll in the surface layer, indicating that the phenomenon of hypoxia was closely related to the growth and standing stock of phytoplankton in the surface layer. The abundant propagation of phytoplankton in the water body of the cline may lead to the emergence of the lower layer of hypoxic zone.
【作者單位】： 中國科學院海洋研究所海洋生態(tài)與環(huán)境科學重點實驗室;中國科學院大學;
【基金】：中國科學院戰(zhàn)略性先導(dǎo)科技專項(A類)資助(XDA11020302);中國科學院“百人計劃”項目資助 國家基金委-山東省聯(lián)合基金項目(U1406403)~~
【分類號】：Q948.8;X55
，

本文編號：2295354