Effects of Storage Container,Storage Time,and Calculation Software on the Measurement of Carbon Dioxide Partial Pressure in Water
This study explores the effects of different storage containers(glass dissolved oxygen bottles and high density polyethylene(HDPE)bottles),storage time,and calculation software programs(CO2SYS and PHREEQC)on the analysis of CO2 partial pressure(p(CO2))and CO2 flux(F(CO2))of water.The results showed that no significant difference(p＞0.05)in the p(CO2)and F(CO2)results was observed between glass dissolved oxygen bottles and HDPE bottles.The storage time showed no significant impact(p＞0.05)on the measurements of p(CO2)and F(CO2),as long as the samples were pass through 0.45 μm microporous filter,kept at(4 ℃),and measured within 24 hours.The calculated p(CO2)values by CO2SYS were approximately only 30％of those by PHREEQC,with a significant difference(p＜0.05).The possible reason could be that PHREEQC considers karstification,while CO2SYS did not.However,in the assessments of the effects of water characteristics(chemical oxygen demand(COD),total nitrogen,nitrate nitrogen,ammonia nitrogen,total phosphorus,total chlorophyll,dissolved oxygen(DO),and carbonate mineral saturation index)on the p(CO2)and F(CO2)of water,the patterns obtained by the two software programs were consistent.
partial pressure of carbon dioxidestorage containerstorage timeCO2SYS softwarePHREEQC software
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万方数据
