茂兰原生森林区岩溶流域水循环碳汇效应

岩溶作用过程积极的参与着碳循环,但在全球碳循环研究中并未对其加以重视。以自动化监测技术为手段,对处于茂兰原生森林区板寨地下河流域进行了一个水文年的实时监测,发现该流域水循环岩溶碳汇值高达353.16tC/a,折合11.8tC/(km2·a)。在此过程中,水循环方式是影响岩溶碳汇的主要因子,潮湿多雨、蒸发量小的天气有利于流域产流,从而可增强碳汇。基于前期森林调查数据,计算得该流域森林植被光合作用碳汇值为454.14tC/a,相当于该区岩溶碳汇的1.3倍。由于光合作用碳汇远大于森林植被的净碳汇,且该区代表了亚热带岩溶区森林顶级生态系统及亚热带岩溶区森林碳汇的最高水平。这说明在亚热带岩溶区,水循环碳汇量与森林植被净碳汇量同等重要,甚至更重要。

Carbon Sequestration during Karst Water Cycle Process in the Maolan Primary Forest Area

Although karst carbon squestration is not attached importance in the model of global carbon cycle, the karst process always takes part in the carbon cycle. Based on the data for nearly one hydrological year under the measurement of auto-monitoring skill in the Banzhai subterranean stream, the Maolan National Nature Reserve of Guizhou (MNRG), the karst carbon squestration (KCS) in the stream catchment is higher than 355.51 tC/a, equivalent to 11.8 tC/(km²·a). Water cycle model is the main factor during this process. The weather with wet air, smaller evaporation is good for runoff yield and KCS. The photosynthetic carbon sequestration (PCS) is also calculated using the data from forest survey. It is about 454.14 tC/a, 1.3 times that of KCS. It is known that the PCS is greater than forest net carbon sequestration (FNCS). MNRG has the climax forest ecosystem and the maximum FNCS of subtropical karst area. The above results showed that the KCS during water cycle process is equivalent to, or more than, FNCS in subtropical karst area.