摘要
以岩性相近但气候和土地利用迥异的两个具有高分辨率水文水化学自动监测数据的岩溶水系统——湿润亚热带以土质坡地为主的岩溶水系统(贵州普定后寨岩溶水系统)和高寒冰雪覆盖下以石质坡地为主的岩溶水系统(瑞士阿尔卑斯山区的Tsanfleuron冰川岩溶水系统)作为研究对象,进行岩溶作用碳汇强度对比研究。结果发现,后寨岩溶水系统的[HCO3-]年均值为222mg/L,而Tsanfleuron冰川岩溶水系统的[HCO3-]年均值仅为131mg/L,表明湿润亚热带岩溶水系统具有较高的[HCO3-]特征。然而,湿润亚热带岩溶水系统的碳汇强度(60.82t/(km2·a))与Tsanfleuron冰川岩溶水系统的碳汇强度(59.06t/(km2·a))相当。冰川岩溶水系统同样具有较高岩溶作用碳汇强度的原因主要是在全球变暖的背景下,冰川退缩加剧,冰川固体水库水量释放增多,致使冰川岩溶水系统径流量显著增加效应超出因稀释作用而产生的[HCO3-]降低效应,进而使得山岳冰川岩溶水系统的碳汇强度增大。这也暗示着随着某些冰川融化,径流量逐渐减小将使岩溶作用碳汇强度降低。
A comparative study on karst process-related carbon sink intensity between the two karst water systems with similar lithology but different climate and land use scenarios and with high resolution hydrological and hydrochemical automatic monitoring data is presented to show the significance of runoff in determining the carbonate weathering carbon sink intensity. The two systems are Houzhai karst water system with high ratio of soil cover in catchment area （Puding County, Guizhou Province, Southwest China）, and Tsanfleuron glaciated and snow covered rocky karst water system in Alps, Switzerland. The results show that the annual mean concentration of HCO3-of Houzhai karst water systems in their discharge areas is 222 mg/L, while that of Tsanfleuron karst water system is only 131 mg/L. This indicates that the karst water systems in humid subtropics were characterized by high [HCO3-]. However, the carbon sink intensity of the karst water system in humid subtropics （60.82 t/（km2·a）） was almost the same as that of Tsanfleuron glaciated karst water system （59.06 t/（km2·a））. The reason for the high carbon sink intensity in glaciated karst water system was mainly that under the global warming conditions, the glacier melts more quickly, and the effect of resulting runoff increase was much stronger than that of [HCO3-] decrease by dilution, so the carbon sink intensity of alpine glaciated karst water system increased instead. It also implies that the karst process-related carbon sink intensity in glaciated karst water systems will decrease if some glaciers disappear due to global warming.
出处
《气候变化研究进展》
CSCD
2011年第3期162-170,共9页
Climate Change Research
基金
中国科学院“百人计划”项目
国家自然科学基金项目(40872168)
