长江营养盐浓度的增加对邻近海区海–气CO_2通量的影响  

Influence of Increasing Nutrients of the Changjiang River on Air-sea CO_2 Flux in Adjacent Seas

作　　者：刘哲[1] 罗晓凡[1] 魏皓[2] 赵亮[1] 

机构地区：[1]天津科技大学海洋与环境学院,天津300457 [2]天津大学海洋科学与技术学院,天津300072

出　　处：《天津科技大学学报》2016年第6期55-63,73,共10页Journal of Tianjin University of Science & Technology

基　　金：国家自然科学基金资助项目(41376112;41276016);中国科学院战略性先导科技专项(A类)资助项目(XDA11020305)

摘　　要：近50年来,长江溶解无机氮和溶解无机磷营养盐浓度不断增加,对长江口邻近海区生态系统产生影响的同时,也对海–气CO_2通量带来扰动.基于三维的东中国海生态动力–无机碳循环耦合模型,设计敏感性实验,在不考虑营养盐结构变化的前提下,假设长江营养盐浓度各增加50%,,模拟长江营养盐输入增加情景,探究其对长江口邻近海区海–气CO_2通量的影响.结果表明:与参考实验相比,长江营养盐浓度的增加使得夏季长江浅滩大气CO_2向海通量增加,海表可多吸收约68%,的大气CO_2,而冬季长江浅滩和苏北浅滩大气CO_2向海通量减小,即冬季碳汇作用减弱,全年尺度上长江浅滩吸收CO_2的能力增强约6%,.长江营养盐浓度增加所致的生物效应主控长江口邻近海区溶解无机碳的变化,进而对海–气CO_2通量产生影响.In recent 50 years, the nutrient concentration of the dissolved inorganic nitrogen phosphorus in Changjiang River continued to increase, which has already had certain impact on the ecosystem of Changjiang River estuary and the adjacent seas and also caused disturbances of the air-sea CO2 flux. Based on the three-dimensional ecological dynamic-inorganic carbon cycle coupling model of the East China Sea, sensitivity experiments were designed without considering structural changes in nutrients and assuming that each nutrient concentration of Changjiang River increased by 50%, which simulated the increase of the nutrients in Changjiang River, so as to explore the influence of increasing nutrients on air-sea CO2 flux in adjacent seas of Changjiang estuary. The results show that compared with the reference case, the increased nutrient concentration of Changjiang River has brought about a positive change in the atmospheric CO2 seaward flux about Changjiang Bank. In summer, with the carbon sink strengthened,the sea surface absorbed more atmospheric CO2, about 68%. In winter, the seaward flux of the atmospheric CO2 decreased above Changjiang Bank and Subei Shoal. That is to say, carbon sink was weakened in winter. The CO2 absorption capacity has had an increase of about 6% anmually above Changjiang Bank. The biological effect, due to the increased nutrient concentration of Changjiang River, is the major cause leading to the changes of dissolved inorganic carbon in adjacent seas, which further influenced the air-sea CO2 flux.

关 键 词：海-气CO2通量 营养盐 长江口 生态模型 

分 类 号：P734.4[天文地球—海洋化学]