喀斯特流域是岩石风化碳汇的关键区域,同时也是CO_(2)逸散研究的热点区域。为探究喀斯特地下河涌出后CO_(2)分压(pCO_(2))及其逸散通量的时空变化格局,选择喀斯特流域巴马盘阳河为对象,分析水体的pH、碱度、总溶解性固体(TDS)、溶解无机...喀斯特流域是岩石风化碳汇的关键区域,同时也是CO_(2)逸散研究的热点区域。为探究喀斯特地下河涌出后CO_(2)分压(pCO_(2))及其逸散通量的时空变化格局,选择喀斯特流域巴马盘阳河为对象,分析水体的pH、碱度、总溶解性固体(TDS)、溶解无机碳(DIC)、溶解有机碳(DOC)、pCO_(2)的时空变化特征,探讨pCO_(2)的调控因素并估算了CO_(2)逸散通量。结果表明,流域内地下水碱度、TDS、DIC和pCO_(2)显著高于地表水,表明喀斯特碳酸盐风化释放大量DIC进入地下水,地下水涌出后产生CO_(2)逸散降低了地表水DIC含量和pCO_(2)。在时间尺度上,旱季常规地表、地下水的碱度、TDS、DIC、pCO_(2)、CO_(2)逸散通量均显著高于雨季,主要归结于雨季雨水的稀释效应。然而次降雨事件下地表、地下水的pH、碱度、TDS、DIC、DOC、pCO_(2)无显著性差异,可能由于降雨量不足或降雨持续时间短。研究期间,巴马盘阳河流域地表水、地下水CO_(2)逸散通量范围分别为-0.10~9.20 kg C m^(-2)year^(-1),-0.12~17.28kg C m^(-2)year^(-1),平均CO_(2)逸散通量分别为1.06±1.46 kg C m^(-2)year^(-1)和2.40±3.14 kg C m^(-2)year^(-1),远高于全球主要大型流域的平均CO_(2)逸散通量(0.64 kg Cm^(-2)year^(-1))。阐明喀斯特流域的CO_(2)逸散通量及其时空变化特征对准确评估河流碳收支状况与评估岩石风化碳汇具有重要意义。展开更多
The 3rd Chinese National Arctic Research Expedition （CHINARE-Arctic III） was carried out from July to September in 2008. The partial pressure of CO2 （pCO2） in the atmosphere and in surface seawater were determined...The 3rd Chinese National Arctic Research Expedition （CHINARE-Arctic III） was carried out from July to September in 2008. The partial pressure of CO2 （pCO2） in the atmosphere and in surface seawater were determined in the Bering Sea during luly 11-27, 2008, and a large number of seawater samples were taken for total alkalinity （TA） and total dissolved inorganic carbon （DIC） analysis. The distributions of CO2 parameters in the Bering Sea and their controlling factors were discussed. The pCO2 values in surface seawater presented a drastic variation from 148 to 563 laatm （1 μatm = 1.013 25× 10-1Pa）. The lowest pCOz values were observed near the Bering Sea shelf break while the highest pCO2 existed at the western Bering Strait. The Bering Sea generally acts as a net sink for atmospheric CO2 in summer. The air-sea CO2 fluxes in the Bering Sea shelf, slope, and basin were estimated at -9.4, -16.3, and -5.1 mmol/（m2.d）, respectively. The annual uptake of CO2 was about 34 Tg C in the Bering Sea.展开更多
文摘喀斯特流域是岩石风化碳汇的关键区域,同时也是CO_(2)逸散研究的热点区域。为探究喀斯特地下河涌出后CO_(2)分压(pCO_(2))及其逸散通量的时空变化格局,选择喀斯特流域巴马盘阳河为对象,分析水体的pH、碱度、总溶解性固体(TDS)、溶解无机碳(DIC)、溶解有机碳(DOC)、pCO_(2)的时空变化特征,探讨pCO_(2)的调控因素并估算了CO_(2)逸散通量。结果表明,流域内地下水碱度、TDS、DIC和pCO_(2)显著高于地表水,表明喀斯特碳酸盐风化释放大量DIC进入地下水,地下水涌出后产生CO_(2)逸散降低了地表水DIC含量和pCO_(2)。在时间尺度上,旱季常规地表、地下水的碱度、TDS、DIC、pCO_(2)、CO_(2)逸散通量均显著高于雨季,主要归结于雨季雨水的稀释效应。然而次降雨事件下地表、地下水的pH、碱度、TDS、DIC、DOC、pCO_(2)无显著性差异,可能由于降雨量不足或降雨持续时间短。研究期间,巴马盘阳河流域地表水、地下水CO_(2)逸散通量范围分别为-0.10~9.20 kg C m^(-2)year^(-1),-0.12~17.28kg C m^(-2)year^(-1),平均CO_(2)逸散通量分别为1.06±1.46 kg C m^(-2)year^(-1)和2.40±3.14 kg C m^(-2)year^(-1),远高于全球主要大型流域的平均CO_(2)逸散通量(0.64 kg Cm^(-2)year^(-1))。阐明喀斯特流域的CO_(2)逸散通量及其时空变化特征对准确评估河流碳收支状况与评估岩石风化碳汇具有重要意义。
基金The National Natural Science Foundation of China (NSFC) under contract Nos 40976116 and 40531007the Fujian Science Foundation under contract No.2009J06025+3 种基金the SOA Youth Foundation Grant under contract No.2012538the Chinese Projects for Investigations and Assessments of the Arctic and Antarctic under contract Nos CHINARE2012: 01-04, 02-01, 03-04, 04-03, 04-04, and CHINARE2013: 01-04, 02-01, 03-04, 04-03, 04-04the Chinese International Cooperation Projects under contract Nos IC201114, IC201201, IC201308, and HC120601the Scientific Research Foundation of Third Institute of Oceanography, SOA under contract Nos 2012006 and 2014006
文摘The 3rd Chinese National Arctic Research Expedition （CHINARE-Arctic III） was carried out from July to September in 2008. The partial pressure of CO2 （pCO2） in the atmosphere and in surface seawater were determined in the Bering Sea during luly 11-27, 2008, and a large number of seawater samples were taken for total alkalinity （TA） and total dissolved inorganic carbon （DIC） analysis. The distributions of CO2 parameters in the Bering Sea and their controlling factors were discussed. The pCO2 values in surface seawater presented a drastic variation from 148 to 563 laatm （1 μatm = 1.013 25× 10-1Pa）. The lowest pCOz values were observed near the Bering Sea shelf break while the highest pCO2 existed at the western Bering Strait. The Bering Sea generally acts as a net sink for atmospheric CO2 in summer. The air-sea CO2 fluxes in the Bering Sea shelf, slope, and basin were estimated at -9.4, -16.3, and -5.1 mmol/（m2.d）, respectively. The annual uptake of CO2 was about 34 Tg C in the Bering Sea.
