半干旱岩溶区土壤次生碳酸盐比例及对岩溶碳汇计算的影响

发布时间：2018-06-23 22:14

本文选题：岩溶碳汇 + 碳酸盐　；参考：《中国岩溶》2016年02期

【摘要】：定量评价半干旱岩溶区土壤次生碳酸盐比例和来源有助于认识土壤系统影响岩溶作用的机理。选取山西晋中盆地西南,吕梁山东侧的半干旱岩溶区马跑神泉小流域为研究对象,通过对林地、退耕地、灌丛地土壤剖面进行分层取样并测定碳酸盐含量及其δ~(13) C、CO_2浓度及其δ~(13) C值,分析其随深度的变化规律和控制因素;并结合研究区碳酸盐岩的δ~(13) C值计算3个剖面各层土壤次生碳酸盐所占比例。研究结果表明:3个土壤剖面的碳酸盐含量、CO_2浓度在0~50cm土层随深度增加而增加,在50~70cm土层随深度增加而减少;土壤碳酸盐δ~(13) C值、δ~(13) C_(CO_2)值在0~50cm土层随深度增加而偏负,在50~70cm土层随深度增加而偏重;土壤碳酸盐含量及其δ~(13) C值主要受次生碳酸盐比例控制,而土壤CO_2及其δ~(13) C_(CO_2)值在上层主要受大气CO_2和土壤有机质分解生成的CO_2共同影响,下层还受土-岩界面岩溶作用过程制约;退耕地、林地、灌丛剖面次生碳酸盐所占比例的均值分别为52%、42%和32%,证实北方半干旱岩溶区土壤中存在原生碳酸盐向次生碳酸盐转化过程。
[Abstract]:The quantitative evaluation of the proportion and source of secondary carbonate in the semiarid karst area is helpful to understand the mechanism of soil system affecting karst. The research object is to select the sham spring small watershed in the semiarid karst area of Jinzhong basin in Shanxi and Shandong side of Lvliang, and to sample and measure the soil profile of the forest land, the land of the cultivated land and the shrub land. The carbonate content, the concentration of delta ~ (13) C, CO_2 and its ~ (13) C value, analyze its variation and control factors with the depth, and calculate the proportion of the secondary carbonate in the soil of the 3 sections with the value of the delta ~ (13) C of the carbonate rock in the study area. The results show that the carbonate content of the 3 soil profiles and the CO_2 concentration in the 0~50cm soil layer follow the depth. The increase in the 50~70cm soil layer decreases with the depth of the soil, and the value of soil carbonate delta ~ (13) C and delta ~ (13) C_ (CO_2) is negative in the 0~50cm soil layer as the depth increases with the depth, and the soil carbonate content and its delta ~ (13) C value are controlled by the secondary carbonate ratio, while the soil CO_2 and its delta ~ (13) C_ (CO_2) values are the values of soil carbonate content and its delta ~ (13) C value. The upper layer is mainly influenced by the CO_2 of the atmospheric CO_2 and the decomposition of soil organic matter. The lower layer is also restricted by the karst process of the soil rock interface, and the proportion of the secondary carbonate in the farmland, the woodland and the shrub section is 52%, 42% and 32% respectively. Process.
【作者单位】：中国地质大学环境学院;中国地质科学院岩溶地质研究所/国土资源部广西壮族自治区岩溶动力学重点实验室;
【基金】：国家自然科学基金项目(41302211) 中国地质调查项目(12120113005200)
【分类号】：S151.9

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