喀斯特不同土地利用方式土壤有机碳矿化特征及其影响因素  

Characteristics of soil organic carbon mineralization and its influencing factors under different land use types in karst areas

作　　者：黎俊 杜馨如 莫小亮 张婷 黄婧 贺同鑫 裴广廷 宋立全 孙立飞 孙建飞 胡宝清 张伟东[4] LI Jun;DU Xinru;MO Xiaoliang;ZHANG Ting;HUANG Jing;HE Tongxin;PEI Guangting;SONGLiquan;SUN Lifei;SUN Jianfei;HU Baoqing;ZHANG Weidong(Key Laboratory of Environment Change and Resources Use in Beibu Gulf,Ministry of Education,Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation Nanning Normal University,Nanning 530001,China;School of Geography and Planning,Nanning Normal University,Nanning 530001,China;Nonggang Karst Ecosystem Observation and Research Station of Guangxi,Chongzuo 532499,China;Huitong Experimental Station of Forest Ecology,Chinese Academy of Sciences,Huitong 418307,China)

机构地区：[1]南宁师范大学北部湾环境演变与资源利用教育部重点实验室,广西地表过程与智能模拟重点实验室,南宁530001 [2]南宁师范大学地理科学与规划学院,南宁530001 [3]弄岗喀斯特生态系统广西野外科学观测研究站,崇左532499 [4]中国科学院会同森林生态实验站,亚热带森林生态系统结构与服务功能湖南省重点实验室,会同418307

出　　处：《生态学报》2025年第2期730-742,共13页Acta Ecologica Sinica

基　　金：广西重点基金(2020GXNSFDA238010);弄岗喀斯特生态系统广西野外科学观测研究站科研能力建设项目(桂科23-026-273);国家自然科学基金(42061009)。

摘　　要：土壤有机碳(SOC)矿化直接影响土壤养分循环和大气CO_(2)浓度,对维持土壤肥力和全球碳循环具有不容忽视的影响。探究喀斯特地区不同土地利用方式土壤有机碳矿化的特征及其影响因素,对深入理解喀斯特地区碳循环和石漠化生态恢复有重要意义。在广西马山县选取5种不同土地利用方式(玉米地、草地、金银花、人工林和灌木林),通过为期30 d的矿化培养,结合土壤性质、微生物群落结构等指标变化,探究不同土地利用方式SOC矿化特征及其调控机制。结果表明:(1)相较于玉米地而言,灌木林和人工林的SOC矿化显著提高,而金银花和草地无显著差异。由于人工林SOC矿化潜力大且碳存留能力相对较弱,在人为干扰或全球变化背景下更容易发生碳流失。而灌木林、草地和金银花具有较高的固碳能力,能存留更多的SOC,因此可作为石漠化区退耕还林的优选模式。(2)表层土壤的有机碳矿化高于深层土壤,但其高的碳输入、较低的有机碳矿化常数和相当的固碳能力促进表层SOC存留。(3)冗余分析结果表明,土壤理化性质解释了SOC矿化特征的65.50%,其中SOC、微生物碳、可溶性碳和Ca^(2+)是解释喀斯特SOC矿化的重要土壤因子。细菌和真菌群落结构分别解释了有SOC矿化特征的66.50%和19.80%,其中拟杆菌门细菌、放线菌门细菌和被孢霉门真菌是调控SOC矿化的主要微生物类群;而细菌多样性和真菌多样性对土壤有机碳矿化特征的变化均无显著影响。综上,土地利用方式不同导致土壤碳底物和Ca^(2+)的变化影响微生物群落结构,特别是特定微生物组群,进而调控SOC矿化。Soil organic carbon mineralization is the main way of carbon output,which directly affects soil nutrient cycling and atmospheric CO_(2)concentration,and plays an important role in maintaining soil fertility and global carbon cycling.It is of great significance to explore the characteristics of soil organic carbon mineralization and influencing factors under different land use types,which is beneficial to understand the carbon cycling and ecological restoration in karst areas.Five land use types(corn field,grassland,Lonicera Japonica,planted forest and shrubland)were selected in Mashan County,Guangxi.The mineralization culture was carried out for 30 days,and the changes in soil and microbial properties were measured,which were used to analyze characteristics of soil organic carbon mineralization and its influencing factors under different land use types in karst areas.The results showed that:(1)Soil organic carbon mineralization significantly increased in the shrubland and planted forest compared with corn field,while there was no difference in grassland and Lonicera Japonica.However,the carbon mineralization potential of planted forest was larger and the carbon retention capacity was relatively weaker compared to other land use types,indicating that the high carbon loss potential in planted forest under human disturbance and global changes.High carbon sequestration capacity occurred in shrubland,grassland and Lonicera Japonica,indicating that the three land use types can retain more soil organic carbon.Thus,these can be used as the optimized model for Grain for Green in rocky desertification areas.(2)soil organic carbon mineralization in surface soil was higher than that in deep soil,but the higher carbon input,the lower soil organic carbon mineralization constant and the same carbon sequestration capacity promoted the retention of soil organic carbon in surface soil.(3)Redundancy analysis results showed that soil properties explained 65.50%of the changes in soil organic carbon mineralization characteristics,and

关 键 词：喀斯特 土地利用方式 有机碳矿化 有机碳累积矿化率 土壤微生物 

分 类 号：S153.6[农业科学—土壤学]