岩溶作用碳汇强度变化的土地利用调控规律——贵州普定岩溶水-碳通量大型模拟试验场研究  

Karst-related carbon sink flux variations caused by land use changes:an example from the Puding karst test site in Guizhou

作　　者：朱辉[1] 曾成[2,3] 刘再华[2,3] 曾庆睿[2,3,4] 李玲珑[2,3,4] 

机构地区：[1]中国地质大学(武汉)环境学院,湖北武汉430074 [2]中国科学院地球化学研究所环境地球化学国家重点实验室,贵州贵阳550081 [3]中国科学院地球化学研究所贵州省科技厅普定喀斯特研究综合试验站,贵州普定562100 [4]中国科学院大学,北京100049

出　　处：《水文地质工程地质》2015年第6期120-125,共6页Hydrogeology & Engineering Geology

基　　金：国家973重大科学研究计划(2013CB956700);国家自然科学基金重点项目(41430753);贵州省科技厅社会攻关计划基金(黔科合SY字(2013)3163号)

摘　　要：针对野外监测面临的岩溶流域边界难以确定以及多种土地利用混杂在一起的问题,在贵州普定建设了不同土地利用条件下岩溶水-碳通量大型模拟试验场,监测研究了不同土地利用条件下的入渗系数和岩溶作用碳汇强度。结果表明,不同土地利用条件下的入渗系数和岩溶作用碳汇强度差异明显,径流强度强烈影响着岩溶作用碳汇强度,模拟裸岩地、荒地、农耕地、草地、灌木地的碳汇强度分别为14.31、12.27、11.79、9.17和12.24 t/(km2·a)。与传统认识不同的发现是,生物量最大的草地,其岩溶作用碳汇强度最小,而裸岩地的岩溶作用碳汇强度最大。这表明:在试验场尺度下,不同土地利用通过改变径流强度和土壤CO2含量这两个因素,对岩溶作用碳汇强度产生影响,且因水化学的恒定行为,径流强度决定碳汇强度,因此在考虑生态系统修复时,不仅需要考虑生物量增加带来的增汇效应,还要考虑到径流强度降低带来的减汇效应。High-precision evaluation of the difference in karst-related water-carbon flux variations caused by land use changes is important to the evaluation of water resources and carbon sink after the control of rocky desertification. Since there are difficulties in determining the karst basin boundaries and separating different land uses in a field study,the test site were built to monitor the variations in coefficient infiltration and carbon sink flux under different land uses in Puding of Guizhou. It was found that the coefficient infiltration and carbon sink flux differ dramatically under different land uses and run off dominated in the karst-related carbon sink flux. The carbon sink fluxes of the simulated bare rock land,bare land,farm land,grass land and brush land were14. 31,12. 27,11. 79,9. 17 and 12. 24 t /（ km·a）（ C） respectively. An interesting finding is that the grass land with largest biomass had the minimum karst-related carbon sink flux while the bare rock land had the maximum karst-related carbon sink flux. The results indicate that the land use influences the karst-related carbon sink flux by changing the runoff intensity and soil CO2-induced HCO3-concentration,but the former plays a leading role because of the chemostatic behavior of HCO3-. In conclusion,we note that the decrease effect on the carbon sink caused by the decrease in run off while restoring the ecosystem should be considered although the increase effect on the carbon sink caused by the increase of biomass is taken into account.

关 键 词：岩溶作用碳汇强度 土地利用调控 普定岩溶水-碳通量模拟试验场 

分 类 号：P641.5[天文地球—地质矿产勘探]