为了解寒旱区内陆河流域碳通量的年际变化及其控制机制,使用涡度相关技术和气象观测系统同步对黑河流域典型生态系统(草地、农田、湿地、荒漠、森林)的碳通量和气象环境要素进行了长期定位观测.分析观测数据显示:黑河流域内农田(玉米)生长季净生态系统生产力(NEP)与总初级生产力(GPP)最大(729.81 g C/m2/a与 1 184.60 g C/m2/a),戈壁荒漠最小(94.18 g C/m2/a与 134.97 g C/m2/a);湿地生长季生态系统呼吸(Reco)最大(460.22 g C/m2/a),戈壁荒漠最小(41.18 g C/m2/a).黑河上游高寒生态系统温度对NEP、GPP和Reco年际变化的解释度明显高于黑河中下游干旱生态系统,而上游高寒生态系统土壤水分对NEP、GPP和Reco年际变化的解释度低于中下游干旱生态系统.在上游的高寒生态系统中,各站点间温度与NEP、GPP和Reco为正相关,而在中下游则为负相关.浅层土壤水分在黑河流域内高寒区和干旱区均与生态系统的NEP、GPP和Reco为正相关,上游高寒区浅层土壤水分与NEP、GPP和Reco的相关性要高于深层土壤水分,而中下游干旱区则是深层土壤水分与NEP、GPP和Reco的相关性更高.
Interannual Change Control Mechanism of Carbon Flux in Inland River Basins in Cold and Arid Regions
In order to understand the interannual variation and control mechanism of carbon fluxes in inland river basins in cold and arid regions,an integrated watershed-scale flux observing network has been constructed for the main ecosystems in the Heihe River basin,including alpine ecosystems in the upper reaches and arid ecosystems in the lower reaches.The observed data analysis indicates that the annual net ecosystem productivity(NEP)and annual gross primary productivity(GPP)were the largest at the cropland site(maize,729.81 g C/m2/a and 1 184.60 g C/m2/a)and the smallest at the Gobi desert site(94.18 g C/m2/a and 134.97 g C/m2/a)in the Heihe River basin.As to the annual ecosystem respiration(Reco),the wetland ecosystem was the largest(460.22 g C/m2/a),and the Gobi desert ecosystem was the smallest(41.18 g C/m2/a).The explaining capacity of the temperature to GPP,NEP and Reco inter-annual variability is higher in the alpine ecosystems than that in the arid ecosystems.In comparison,the explaining capacity of the soil moisture to GPP,NEP and Reco inter-annual variability is lower in the alpine ecosystems than that in the arid ecosystems.In the upper reaches,GPP,NEP and Reco are positively correlated with GPP,NEP,Reco among sites,but the opposite is true in the middle and down reaches.The shallow soil moisture is positively correlated with NEP,GPP and Reco among all sites in the Heihe River basin.In the upstream,shallow soil moisture is more closely correlated with NEP,GPP and Reco than deep soil moisture,but the deep soil moisture is more closely correlated with NEP,GPP and Reco than shallow soil moisture in the middle and lower reaches.
carbonHeihe River basingross primary productivitynet ecosystem productivityecosystemsenvironmental geology
NETL
NSTL
万方数据
