为了掌握亚热带季风气候岩溶地区流域水化学变化特征及量化流域内岩石化学风化过程对吸收大气CO2的贡献,文章选取湘西峒河流域作为研究对象,于2016年7—8月对研究区干流和7个子流域进行了水样采集与分析。结果表明:河水pH平均值为8. 31...为了掌握亚热带季风气候岩溶地区流域水化学变化特征及量化流域内岩石化学风化过程对吸收大气CO2的贡献,文章选取湘西峒河流域作为研究对象,于2016年7—8月对研究区干流和7个子流域进行了水样采集与分析。结果表明:河水pH平均值为8. 31,总体呈偏碱性。EC与TDS的变化范围较大,这主要与流域内岩性的分布有关。水中离子以Ca2+、HCO3-为主,水化学类型为HCO3—Ca型,岩性控制水化学的组成。HCO3-、Ca2+和Mg2+主要来源于碳酸盐岩的风化,其余离子来源多受人为活动影响。峒河流域干流的主要离子中,HCO3-、Ca2+和Mg2+浓度从上游至下游总体下降,反映了河流从碳酸盐岩区流向碎屑岩为主地层的过程。NO3-、K+、Na+、F-、Cl-和SO24-呈增长趋势,说明峒河受人为污染影响较大,反映出人为活动的密集程度。通过子流域的划分可知流域上游主要受灰岩以及白云岩控制,中游以灰岩控制为主,下游受砂岩、泥岩及碎屑岩控制为主。收集流域最终出口吉首观测站一个水文年的数据并运用水化学—径流法估算出峒河流域无机碳通量为60 477. 33 t CO2/a,碳汇强度为71. 15 t CO2/(km2·a)。展开更多
On the basis of mineralogical, geochemical and micro\|textural studies of the typical sections of the red weathering crust of carbonate rocks in the subtropical karst areas of Guizhou Province and Guangxi Autonomous R...On the basis of mineralogical, geochemical and micro\|textural studies of the typical sections of the red weathering crust of carbonate rocks in the subtropical karst areas of Guizhou Province and Guangxi Autonomous Region, we have found, either on a microscopic or on a macroscopical scale and in different positions of the sections, the most direct and most important mineralogical and micro\|textural evidence for the development of metasomatism in the process of weathering\|pedogenesis of numerous carbonate rocks. This paper also has expounded for the first time and systematically the mechanism of metasomatism involved in the process of weathering\|pedogenesis of carbonate rocks and proposed the sequence of mineral metasomatic evolution in the process of weathering\|pedogenesis of carbonate rocks.展开更多
文摘为了掌握亚热带季风气候岩溶地区流域水化学变化特征及量化流域内岩石化学风化过程对吸收大气CO2的贡献,文章选取湘西峒河流域作为研究对象,于2016年7—8月对研究区干流和7个子流域进行了水样采集与分析。结果表明:河水pH平均值为8. 31,总体呈偏碱性。EC与TDS的变化范围较大,这主要与流域内岩性的分布有关。水中离子以Ca2+、HCO3-为主,水化学类型为HCO3—Ca型,岩性控制水化学的组成。HCO3-、Ca2+和Mg2+主要来源于碳酸盐岩的风化,其余离子来源多受人为活动影响。峒河流域干流的主要离子中,HCO3-、Ca2+和Mg2+浓度从上游至下游总体下降,反映了河流从碳酸盐岩区流向碎屑岩为主地层的过程。NO3-、K+、Na+、F-、Cl-和SO24-呈增长趋势,说明峒河受人为污染影响较大,反映出人为活动的密集程度。通过子流域的划分可知流域上游主要受灰岩以及白云岩控制,中游以灰岩控制为主,下游受砂岩、泥岩及碎屑岩控制为主。收集流域最终出口吉首观测站一个水文年的数据并运用水化学—径流法估算出峒河流域无机碳通量为60 477. 33 t CO2/a,碳汇强度为71. 15 t CO2/(km2·a)。
基金This research project was financially supported by both National Natural Science Foundation of China (GrantNo .4 980 0 0 3)andCross Century Qualified Personnel Program of Guizhou Province
文摘On the basis of mineralogical, geochemical and micro\|textural studies of the typical sections of the red weathering crust of carbonate rocks in the subtropical karst areas of Guizhou Province and Guangxi Autonomous Region, we have found, either on a microscopic or on a macroscopical scale and in different positions of the sections, the most direct and most important mineralogical and micro\|textural evidence for the development of metasomatism in the process of weathering\|pedogenesis of numerous carbonate rocks. This paper also has expounded for the first time and systematically the mechanism of metasomatism involved in the process of weathering\|pedogenesis of carbonate rocks and proposed the sequence of mineral metasomatic evolution in the process of weathering\|pedogenesis of carbonate rocks.
