清水江流域岩石风化特征及其碳汇效应

发布时间：2018-03-25 10:18

本文选题：碳汇　切入点：化学风化　出处：《环境科学》2016年12期

【摘要】：岩石风化产生的碳汇是全球碳循环的重要组成部分,文中对清水江流域主要离子组成进行分析测定,通过主成分分析、化学物质平衡法和扣除法估算流域岩石风化速率及对大气CO_2的消耗量.结果表明,流域河水溶质主要来源于碳酸盐岩和硅酸盐岩风化,并以碳酸盐岩风化为主.碳酸盐、硅酸盐、大气CO_2对河水溶质的贡献率分别为58.28%、17.38%、17.74%.流域岩石化学风化速率为109.97 t·(km~2·a)~(-1),与乌江接近,高于全球流域均值.流域岩石风化对大气CO_2的消耗通量为7.25×10~5mol·(km~2·a)~(-1),岩石风化对大气CO_2的消耗量为12.45×10~9mol·a~(-1),其中,碳酸盐岩风化消耗量占63.13%,为7.86×10~9mol·a~(-1),硅酸盐岩风化消耗量占36.87%,为4.59×10~9mol·a~(-1).SO_4~(2-)、F~-、NO_3~-的相关分析及空间分布特征表明,人为活动对清水江流域河水溶质的影响不容忽视,其贡献率为4.87%.
[Abstract]:The carbon sink produced by rock weathering is an important part of the global carbon cycle. The chemical balance method and deduction method are used to estimate the weathering rate of rocks and the consumption of atmospheric CO_2 in the basin. The results show that the solute of river water mainly comes from the weathering of carbonate rock and silicate rock, and mainly from carbonate rock weathering. The contribution rates of silicate and atmospheric CO_2 to the solute of river water are 58.28% and 17.38% and 17.74% respectively. The chemical weathering rate of rocks in the basin is 109.97 t / kg / kg ~ (2) / a ~ (-1) ~ (-1), which is close to Wujiang River. The consumption flux of atmospheric CO_2 by rock weathering in the basin is 7.25 脳 10~5mol / km-1 ~ (-1), and the consumption of atmospheric CO_2 by rock weathering is 12.45 脳 10~9mol ~ (-1) ~ (-1). The weathering consumption of carbonate rock accounts for 63.13, which is 7.86 脳 10~9mol / a ~ (-1), and silicate rock's weathering consumption is 36.87, and the correlation analysis and spatial distribution of the correlation of weathering consumption of carbonate rock and silicate rock are 4.59 脳 10~9mol / a ~ (-1). So ~ (4) ~ (4) ~ (4) ~ (4) ~ (4) ~ (-) ~ (-) ~-and its spatial distribution characteristics show that the influence of human activities on the solute content of river water in Qingshui River basin can not be ignored, and its contribution rate is 4.87 ~ (th).
【作者单位】：贵州大学资源与环境工程学院;贵州大学喀斯特环境与地质灾害防治重点实验室;中国科学院地球化学研究所环境地球化学国家重点实验室;
【基金】：国家自然科学基金项目(42603123) 中国博士后科学基金项目(2014M562388) 水利部公益性行业科研专项(201401050)
【分类号】：P512.1;X14

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