摘要
稳定碳同位素技术能够指示生态系统的物质循环与能量流动,根据生态系统碳转移动态,可以探明生态系统中碳循环过程和固碳能力。以科尔沁沙地半流动沙丘固沙植被差巴嘎蒿(Artemisia halodendron)、半流动半固定沙丘固沙植被小叶锦鸡儿(Caragana microphylla)和黄柳(Salix gordejevii Chang),以及在草甸地广泛分布的芦苇(Phragmites australis)与玉米(Zea mays Linn)5种典型植被为研究对象,分析了各植被群落冠层处大气、叶片、凋落物、土壤连续体的δC值和碳含量的分布特征及各组分间的关系。结果表明:沙丘植被冠层处大气CO_(2)浓度显著低于草甸植被,受控于土壤水分特征和植物生长特性。在逆境胁迫下,小叶锦鸡儿叶片水分利用效率最高,固碳耗水成本最低。叶片碳含量和δC值均受叶片生育期的影响,新叶片潜在碳蓄积能力更强,水分利用效率更高。叶片凋落物δC值在不同植被间存在显著差异,说明了植物功能性的驱动作用。随着土壤深度的增加,有机质分解彻底,土壤有机碳含量减小,δC值呈偏正的趋势。沙丘土壤δC值高于草甸,沙丘土壤有机碳周转速率高于草甸,土壤类型对有机碳周转影响较大。有助于深入理解沙地-草甸相间地区碳循环关键过程,为荒漠化治理提供理论依据。
Stable carbon isotope technology can indicate the material cycle and energy flow of ecosystem.According to the carbon transfer dynamics of ecosystem,the carbon cycle process and carbon fixation capacity of ecosystem can be explored.Artemisia halodendron,Caragana microphylla and Salix gordejevii Chang,as well as Phragmites australis and Zea mays Linn,which are widely distributed in the meadow,were selected as the research objects.The characteristics of atmosphere,leaves,litter and soil continuumδC value at the canopy of each vegetation community,the distribution characteristics of carbon content and the relationship between components were analyzed.The results showed that the atmospheric CO_(2)concentration in the canopy of dune vegetation was significantly lower than that of meadow vegetation,which was controlled by the characteristics of soil moisture and plant growth.Under stress,Caragana microphylla leaves had the highest water use efficiency and the lowest cost of carbon sequestration and water consumption.Leaf carbon content andδC value both were affected by the growth period of leaves.The potential carbon storage capacity of new leaves was stronger and the water use efficiency was higher.There were significant differences in leaf litterδC value among different vegetations,indicating the driving role of plant functionality.With the increase of soil depth,organic matter decomposed completely and the content of soil organic carbon decreased,δC value showed a positive trend.Dune soilδC value was higher than that of meadow,the turnover rate of soil organic carbon in dune was higher than that of meadow,and the soil type had a great impact on the turnover of organic carbon.It is helpful to deeply understand the key process of carbon cycle in sandy meadow alternating areas,and provides a theoretical basis for desertification control.
作者
张苗苗
刘廷玺
段利民
王冠丽
杨宇晗
ZHANG Miaomiao;LIU Tingxi;DUAN Limin;WANG Guanli;YANG Yuhan(Water Conservancy and Civil Engineering College,Inner Mongolia Agricultural University,Hohhot 010018,China;Inner Mongolia Water Resource Protection and Utilization Key Laboratory,Hohhot 010018,China)
出处
《生态学报》
CAS
CSCD
北大核心
2022年第18期7663-7675,共13页
Acta Ecologica Sinica
基金
国家自然科学基金重点国际(地区)合作研究项目、地区项目(51620105003,51869017)
内蒙古自然科学基金重点项目(2018ZD05)
教育部创新团队发展计划(IRT_17R60)。
关键词
半干旱地区
稳定碳同位素
碳周转
有机碳
水分利用效率
semi-arid areas
Stable Carbon Isotope
carbon cycle
organic carbon
water use efficiency
