基于地理探测器的中国陆地生态系统土壤有机碳空间异质性影响因子分析  

Influential Factors Analysis for Spatial Heterogeneity of Soil Organic Carbon in Chinese Terrestrial Ecosystem with Geographical Detector

作　　者：丁倩 张弛[1,3] DING Qian;ZHANG Chi(State Key Laboratory of Desert and Oasis Ecology/Xinjiang Institute of Ecology and Geography,CAS,Urumqi 830011,China;University of Chinese Academy of Sciences,Beijing 100049,China;Research Center for Ecology and Environment of Central Asia,CAS,Urumqi 830011,China)

机构地区：[1]中国科学院新疆生态与地理研究所/荒漠与绿洲生态国家重点实验室,新疆乌鲁木齐830011 [2]中国科学院大学,北京100049 [3]中国科学院中亚生态与环境研究中心,新疆乌鲁木齐830011

出　　处：《生态环境学报》2021年第1期19-28,共10页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(31770515)。

摘　　要：中国陆地生态系统土壤有机碳库对全球生态系统碳平衡具有显著影响。为揭示土壤碳库空间分布的潜在主控因子并为今后建立碳库空间分布模型提供依据,利用地理探测器对中国陆地生态系统表层土壤(0—20 cm)有机碳密度的影响因子(气温、降水量、DEM、NDVI、陆地生态系统类型、人口密度)进行空间分异性探测和定量归因。结果表明:自然因素是全国和区域尺度陆地生态系统表层土壤有机碳密度的主要因素,而人为因素影响较小。全国尺度各影响因子按解释程度大小排序分别为:温度(0.22)>NDVI(0.16)>DEM(0.12)>陆地生态系统类型(0.09)>降水量(0.06)>人口密度(0.04);自然因素中的气候因素是中国陆地生态系统表层土壤有机碳密度空间分异性的主要影响因子,温度与降水量交互作用的解释程度为0.37,其中温度的作用尤为重要;气温因子与土壤有机碳密度在相对寒冷的地区(均温<15℃)呈负相关,但在更热的地区则呈正相关,意味着生态系统碳平衡对未来气候变暖可能表现出异质性的响应特征;强烈的因子互作效应表明,中国陆地生态系统表层土壤有机碳空间分异性是由多种因子共同作用影响而非单一因素决定;中国六大分区(东北、华北、华东、西北、中南、西南)陆地生态系统表层土壤有机碳密度的各影响因子解释程度存在差异,体现出土壤有机碳密度的主控因子的空间异质性。Soil organic carbon pool in terrestrial ecosystem in China has a significant impact on the global ecosystem carbon balance.In order to explore potential dominant factors of the spatial distribution of soil carbon pool and provide the basis for establishing the spatial distribution model of soil carbon pool in the future,the influential factors(temperature,precipitation,DEM,NDVI,terrestrial ecosystem types,population density)of spatial heterogeneity of soil organic carbon density on the surface(0‒20 cm)in terrestrial ecosystem in China were detected and quantitatively attributed by the geographic detector.The results show that natural factors are dominant factors of soil organic carbon density in large scale or medium scale terrestrial ecosystems,but human factors have little influence.The explanatory power of each influential factor in large scale is as follows:temperature(0.22),NDVI(0.16),DEM(0.12),terrestrial ecosystem types(0.09),precipitation(0.06),population density(0.04).Climate is the primary factor influencing the spatial heterogeneity of organic carbon density in topsoil of terrestrial ecosystems in China,especially temperature.The explanatory power of the interaction between temperature and precipitation is 0.37.The temperature factor is negatively correlated with soil organic carbon in relatively cold regions(mean temperature<15℃),but positively correlated with soil organic carbon in hotter regions,indicating that the carbon balance of the ecosystem may show heterogeneous response characteristics to future climate warming.The spatial heterogeneity of soil organic carbon density in terrestrial ecosystems in China is influenced by multiple factors rather than a single factor.The interpretation degree of the influencing factors of soil organic carbon density in terrestrial ecosystems surface in the six regions(Northeast,North,East,Northwest,Central-South and Southwest)is different,which indicates that the main controlling factors of soil organic carbon density have spatial heterogeneity.

关 键 词：土壤有机碳 影响因子 空间异质性 地理探测器 陆地生态系统 

分 类 号：Q142.3[生物学—生态学] X144[生物学—普通生物学]