大气CO_2和O_3浓度升高对淡水环境水化学条件的影响  

Effects of Elevated CO_2 and O_3 on Environmental Chemical Properties in a Stimulated Micro-Aquatic Ecosystem

作　　者：胡正雪[1] 尹颖[1] 艾弗逊[1] 郭红岩[1] 

机构地区：[1]南京大学环境学院污染控制与资源化研究国家重点实验室,南京210023

出　　处：《农业环境科学学报》2014年第11期2213-2220,共8页Journal of Agro-Environment Science

基　　金：国家自然科学基金(21177058)

摘　　要：在开顶式气室OTC(Opentopchamber)平台下,构建微宇宙水环境模拟系统,初步研究了当大气CO2浓度升高200μL·L-1、O3浓度升高50 nL·L-1及其复合作用下,水体理化参数(pH、Eh、可溶态Zn、Mg、Fe以及可溶态总氮、总磷)、沉积物理化性质(pH、Eh、Zn、Mg和Fe的形态)的变化。经5个月的持续观察发现,与正常大气条件相比,CO2升高(600±10)μL·L-1,水体pH下降,可溶态Zn、Mg浓度升高,可溶态总磷浓度无明显变化;O3升高(125±20)nL·L-1,水体pH无明显变化,可溶态Zn、Mg、总磷浓度无明显变化;CO2和O3复合升高[(600±10)μL·L-1CO2,(125±20)nL·L-1O3],水体pH下降,可溶态Zn浓度无明显变化,可溶态Mg、总磷浓度升高。结果表明:CO2单独升高可降低水体pH,促进沉积物对金属元素的释放;O3单独升高对水体pH、沉积物释放元素无明显影响;而CO2+O3复合升高可降低水体pH,促进沉积物对Mg和磷的释放。In this study we investigated the responses of chemical properties in aquatic ecosystem to treatments with elevated CO2 and 03 in open top chamber（ OTC ） for 5 months. The physiochemical parameters of surface water（pH, Eh, soluble Zn, Mg, Fe, TN and TP） and sedi- ments（ pH, Eh,and percentages of Zn, Mg and Fe fractions ） were measured. Elevated CO2[（ 600±10）μL· L^-1] decreased pH, but increased soluble Zn and Mg concentrations in the surface water. Increasing CO2 had no influence on soluble TP in the surface water. Elevated O3 [（ 125±20 ）nL·L^-1] did not influence pH or concentrations of soluble Zn, Mg and TP in the surface water.Elevation of both CO2 and 03[600±10 ）μL· L^-1 CO2, （ 125±20 ）nL·L^-1O3] decreased water pH, whereas increased soluble Mg and TP concentrations significantly. Soluble Zn was not influenced by elevated CO2 and O3 combination. These results indicate that elevated CO2 decreases surface water pH but increases metal concentrations, while elevated O3 has no significant influence on pH or element contents in water. Combination of elevated CO and 03 re- duces pH and enhances Mg and phosphorus in surface water. Further studies are necessary to investigate the mechanisms under which fu- ture atmospheric conditions influence aquatic ecosystem especially under combined CO2 and O3.

关 键 词：CO2 O3 复合效应 水生生态系统 

分 类 号：X131.2[环境科学与工程—环境科学]