黄土高原次生林演替过程土壤有机碳库及其化学组成响应特征  

Response Characteristics of Soil Organic Carbon Pool and Its Chemical Composition During Secondary Forest Succession in the Loess Plateau

作　　者：刘涵宇 刘颖异 张琦 封伦 高起乾 任成杰 韩新辉[1,2,3] LIU Han-yu;LIU Ying-yi;ZHANG Qi;FENG Lun;GAO Qi-qian;REN Cheng-jie;HAN Xin-hui(College of Agronomy,Northwest A&F University,Yangling 712100,China;Shaanxi Engineering Research Center of Circular Agriculture,Yangling 712100,China;Forest Ecosystem Positioning Research Station of Huanglong Mountain,Yan'an 716000,China)

机构地区：[1]西北农林科技大学农学院,杨凌712100 [2]陕西省循环农业工程技术研究中心,杨凌712100 [3]黄龙山森林生态系统国家定位观测研究站,延安716000

出　　处：《环境科学》2023年第4期2275-2282,共8页Environmental Science

基　　金：国家林业和草原局林草科技创新发展与研究项目(2020132111);国家自然科学基金项目(41877543)。

摘　　要：为探明黄土高原次生林演替过程中土壤有机碳库及其化学组成演化特征,选取陕北黄土高原黄龙山林区次生林演替初级阶段(山杨林)、过渡阶段(山杨、辽东栎混交林)和顶级阶段(辽东栎林)样地为研究对象,分析不同土层深度(0~10、 10~20、 20~30、 30~50和50~100 cm)土壤有机碳含量、储量和化学组成变化特征.结果表明:(1)土壤有机碳含量和储量随次生林演替过程显著增加(P<0.05),土壤有机碳含量随土层深度增加显著降低,土壤有机碳储量从初级阶段的64.8Mg·hm^(-2)增加至顶级阶段的129.2Mg·hm^(-2),增加了99%.(2)次生林演替过程中,表层(0~30 cm)土壤有机碳中结构简单、相对易分解的脂肪族碳组分相对含量减少,结构复杂、相对难分解的芳香族碳组分相对含量增加,表明表层土壤有机碳化学组成稳定性随次生林演替过程显著提高,而深层(30~100cm)土壤有机碳化学组成稳定性表现为先增加后降低,即过渡阶段>顶级阶段>初级阶段.(3)次生林演替过程中,初级阶段和过渡阶段土壤有机碳化学组成稳定性随土层深度增加显著增加,顶级阶段整体上趋于稳定,深层土壤碳稳定性略有降低.(4)Pearson相关性分析表明,次生林演替过程中,土壤有机碳储量、化学组成稳定性均与土壤全磷含量呈显著负相关.总的来说,次生林演替过程中0~100cm土壤有机碳含量及储量均显著提升,扮演了“碳汇”的角色,且随次生演替过程,表层(0~30cm)土壤有机碳化学组成稳定性显著增加,深层(30~100 cm)土壤有机碳化学组成稳定性先增加后降低.In order to explore the characteristics of the soil organic carbon(SOC)pool and its chemical composition during the succession of secondary forests in the Loess Plateau,samples of the primary stage(Populus davidiana forest),transition stage(Populus davidiana and Quercus wutaishansea mixed forest),and top stage(Quercus wutaishansea forest)of secondary forest succession in the Huanglong Mountain forest area of the Loess Plateau in Northern Shaanxi were selected as the research object.The variation characteristics of SOC content,storage,and its chemical composition at different soil depths(0-10,10-20,20-30,30-50,and 50-100 cm)were analyzed.The results showed that:①the contents and storage of SOC increased significantly with the secondary forest succession process(P<0.05).The content of SOC decreased significantly with the increase in soil depth,and the storage of SOC increased from 64.8 Mg·hm^(-2) in the primary stage to 129.2 Mg·hm^(-2) in the top stage,with an increase of 99%.②During the succession of secondary forests,in the surface(0-30 cm)soil organic carbon,the relative content of aliphatic carbon components that have a simple structure and can be decomposed more easily decreased,and the relative content of aromatic carbon components that have a complex structure and cannot be decomposed easily increased,indicating that the chemical composition of organic carbon stability of surface-layer soil increased significantly with the process of secondary forest succession.However,the stability of the chemical composition of SOC in the deep layer(30-100 cm)first increased and then decreased,that is,the transition stage>the top stage>the primary stage.③In the process of secondary forest succession,the stability of SOC chemical composition in the primary stage and transition stage increased significantly with the increase in soil depth.The top stage tended to be stable,and the deep soil carbon stability decreased slightly.④Pearson correlation analysis showed that during the secondary forest succession process,S

关 键 词：黄土高原 次生林演替 土壤有机碳化学组成 傅里叶红外光谱技术(FTIR) 土壤有机碳库 

分 类 号：X144[环境科学与工程—环境科学]