Abstract:
China is a country with a large area of karst. It is an important part of the terrestrial carbon cycle that the absorption of CO
2 from soil or atmosphere by karstification would form dissolved inorganic carbon and discharge it to the ocean along rivers. The mechanism, influencing factors and measurement methods of karst carbon sinks have been ascertained by China Geological Survey since the exploratory investigation of karst carbon sinks in 2009.`The results show that the huge potential of karst carbon sinks in China has been revealed by the carbonate rock dissolution tablets, runoff-water chemistry and regression models. The important measures of manual intervention to increase karst carbon sinks include vegetation restoration, soil improvement, allogenic water irrigation, and aquatic plants cultivation. The application of basin-scale karst carbon cycle and carbon sink effect investigation technology has promoted a series of results in the theory, investigation, monitoring technology and platform construction of the karst carbon cycle and carbon sink effect evaluation by geological survey. However, there are still major challenges in the measurement, verification, and manual intervention of karst carbon sinks to sequester and increase carbon sinks, which would need to be tackled and improved during the 14th Five-Year Plan period to meet the goal of geological carbon sinks serving carbon neutrality.