文献类型：期刊文献

中文题名：温带榆树稀树草原碳通量变化特征及环境因子的影响

英文题名：Characteristics of Carbon Flux Variations and Its Effects of Environmental Factors in Temperate Elm Savnanna Ecosystem

作者：杨凯捷[1,2,3] 丛巍巍[4] 陆森[5] 冯益明[1,2,3] 王锋[1,2,3]

第一作者：杨凯捷

机构：[1]中国林业科学研究院生态保护与修复研究所,北京100091;[2]中国林业科学研究院荒漠化研究所,北京100091;[3]三北工程研究院,巴彦淖尔015200;[4]沈阳农业大学,沈阳110161;[5]中国林业科学研究院林业研究所,北京100091

年份：2025

卷号：61

期号：9

起止页码：12-21

中文期刊名：林业科学

外文期刊名：Scientia Silvae Sinicae

收录：;北大核心:【北大核心2023】；

基金：中国林业科学研究院科学基本科研业务费专项(CAFYBB2020QD002,CAFYBB2021MC002,CAFYBB2023ZA009);国家自然科学基金项目(32171875);国家重点研发计划项目(2023YFF1304103)。

语种：中文

中文关键词：榆树稀树草原;涡度相关;净生态系统碳交换量;总初级生产力;通量贡献区

外文关键词：elm savanna;eddy covariance;net ecosystem exchange(NEE)of carbon;gross primary production(GPP);flux footprint

分类号：S718.43

摘要：【目的】明确内蒙古浑善达克沙地榆树稀树草原生态系统的能量通量年变化特征及能量收支平衡,阐明其碳通量的季节和日变化特征及受环境因子的影响。【方法】利用涡度相关系统和气象设备,在2021年全年连续原位观测榆树稀树草原的碳通量、能量通量和环境因子,采用净生态系统碳交换量(NEE)的夜间拆分方法、能量闭合度方法和随机森林算法计算分析碳通量变化特征、能量收支平衡及环境因子的影响。【结果】1)榆树稀树草原2021年全年的潜热、显热占净辐射比值分别为48.6%和41.5%,能量闭合度为73%。2)全年的NEE为-231.77 g·m^(-2),生态系统总初级生产力(GPP)为849.79 g·m^(-2),生态系统呼吸为603.36 g·m^(-2)。研究区在1、2、11和12月表现为碳源,其余月份均为碳汇,其中7月和8月碳汇强度最高(分别为-75.17和-73.75g·m^(-2)),占全年固碳总量的64.1%;在日尺度上,碳通量表现为典型的单峰型变化,夏季碳汇峰值为0.220g·m^(-2)halfhour-1。3)在全年尺度,气温是影响碳通量的主要因子。在季节尺度,总辐射是影响春、夏和冬季NEE的最重要环境因子(重要性分别为47%、37%、35%),土壤含水量则是影响秋季NEE的最重要环境因子(重要性58%);GPP最重要的驱动因子是土壤含水量(重要性分别为:春季72%、夏季46%、秋季61%、冬季32%),其次为总辐射。【结论】榆树稀树草原具有远高于同区域草原生态系统的固碳能力,土壤水分是该生态系统碳通量重要的影响因子。我国浑善达克沙地和科尔沁沙地生态治理中,恢复当地天然植被榆树稀树草原同时具有沙地修复和固碳增汇双重效益。
【Objective】The major objectives of this study are to clarify the annual dynamics of energy fluxes and the energy balance in the Otindag Sandy Land of Inner Mongolia,reveal the seasonal and diurnal patterns of carbon fluxes,and explore how environmental factors influence carbon fluxes in this ecosystem.【Method】An eddy covariance system and meteorological instruments were used to continuously in situ observe the carbon fluxes,energy fluxes,and environmental factors in the elm savanna ecosystem of the Otindag Sandy Land in Inner Mongolia throughout 2021.The nighttime partitioning of net ecosystem exchange(NEE),the energy balance closure method,and the Random Forest algorithm were used to calculate and analyze the variation characteristics of carbon fluxes,energy balance,and the impacts of environmental factors.【Result】1)The study found that in 2021,latent heat and sensible heat accounted for 48.6%and 41.5%of the net radiation in the elm savanna ecosystem,respectively,with an energy closure of 73%.2)The annual NEE of the elm savanna was-231.77 g·m^(-2),the gross primary productivity(GPP)was 849.79 g·m^(-2),and the ecosystem respiration was 603.36 g·m^(-2).The study area served as a carbon source during January,February,November,and December,and a carbon sink during the other months of the year.The carbon sink strength was highest in July and August,with values of-75.17 g·m^(-2)and-73.75 g·m^(-2),respectively,accounting for 64.1%of the annual carbon sequestration.On a daily scale,carbon flux exhibited a typical unimodal variation,with a peak carbon sink of 0.220-2 g·m in summer.3)At the annual scale,air temperature was the primary factor influencing carbon fluxes.At the seasonal scale,total solar radiation was the dominant environmental factor affecting NEE in spring,summer,and winter,with relative importance values of 47%,37%,and 35%,respectively.In autumn,soil water content was the most influential factor,contributing relative importance values of 58%.For GPP,soil water content was the most significant driver across all seasons,accounting for 72%in spring,46%in summer,61%in autumn,and 32%in winter,followed by total solar radiation.【Conclusion】The elm savanna has a much stronger carbon sequestration capacity than other grassland ecosystems in the same region,with soil water content being a key environmental driver of carbon fluxes.In the ecological restoration of the Otindag Sandy Land and the Horqin Sandy Land,the recovery of native elm savanna vegetation can provide dual benefits of sandy land rehabilitation and carbon sequestration increase.