论岩溶作用对全球碳循环的意义与碳汇效应——兼对《对〈中国岩溶作用产生的大气CO_2碳汇分区估算〉一文的商榷》的答复

Significance and carbon sink effects of karst processes in global carbon cycle: Also reply to "Discussion on article 'Calculation of atmospheric CO_2 sink formed in karst processes of karst divided regions in China' "

岩溶作用促进大气二氧化碳汇过程不仅局限于碳酸盐岩地区,而是涉及全球陆地地质岩石地区,因此以前仅考虑岩溶面积计算的岩溶碳汇量偏低,需要以河流流域为单元全面计算全球岩溶碳汇效应。除了产生河流溶解无机碳被带入海洋外,岩溶作用还可通过水体生物吸收形成颗粒有机碳以及在岩溶土壤中固定有机碳等方式形成碳汇,因此,岩溶地质过程固碳形式多样。其中,仅全球水生生物固定岩溶水重碳酸根产生的有机碳近0.5Gt,生态恢复可促进岩溶土壤有机碳固定及岩溶流域碳汇,我国西南石漠化治理工程至少可增加岩溶碳汇2～3亿t,如果重视岩溶增汇技术的应用,全球岩溶碳汇效应将非常显著。所以,岩溶碳汇研究意义重大,岩溶碳汇效应更不可忽略。

Atmospheric CO2 can be absorbed and dissolved in water among karst processes, not only occurred in the carbonate rock area but also in all other rock areas of the global continent. Therefore, the previous cal- culation data of the karst carbon cycle based on the carbonate area is less and should be calculated again based on all river basins in the world. Besides the dissolved inorganic carbon of the rivers into oceans, the carbon sink of karst processes can be formed in particulate organic carbon of waters deposited by aquatic vegetation and the karst soil organie earbon etc. many carbon sequestered fashions. Among them,only the particulate organic carbon of waters deposited by aquatic vegetation absorbed from bicarbonate ions can reach about 0.5 Gt. The ecological rehabilitation can promote the organic earbon fixed in karst soils and inorganic carbon sink of water in the basin. As a result, the treatment engineering of the rocky desertification in southwest China at least can raise karst carbon sink 0.2 to 0.3 Gt. If the carbon sequestered technology in karst proces- ses is considered and applied in ecological rehabilitation of the world, the global carbon sink effects should be very evident.