黄土丘陵区人工刺槐林土壤有机碳矿化特征及其与有机碳组分的关系  

Mineralization Characteristics of Soil Organic Carbon and Its Relationship with Organic Carbon Components in Artificial Robinia pseudoacacia Forest in Loess Hilly Region

作　　者：朱玉帆 刘伟超 李佳欣 苏玉博 简俊楠 杨改河[1,2,3] 任成杰 冯永忠 任广鑫[1,2] 王晓娇[1,2] 韩新辉[1,2,3] ZHU Yu-fan;LIU Wei-chao;LI Jia-xin;SU Yu-bo;JIAN Jun-nan;YANG Gai-he;REN Cheng-jie;FENG Yong-zhong;REN Guang-xin;WANG Xiao-jiao;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;College of Ecology,Lanzhou University,Lanzhou 730000,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 [4]兰州大学生态学院,兰州730000

出　　处：《环境科学》2023年第1期444-451,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);大学生创新创业训练项目(202110712249)。

摘　　要：为了探讨黄土丘陵区人工林有机碳矿化特征及有机碳组分变化规律,选择恢复13 a的人工刺槐林以及临近坡耕地为研究对象,开展3种不同温度处理(15、25和35℃)下的室内培养实验.结果表明,土壤有机碳矿化速率表现出先剧烈下降后平稳的趋势;有机碳累计释放量表现为培养初期增加迅速,后期逐渐缓慢;坡耕地土壤有机碳矿化对温度的变化更为敏感,其温度敏感性系数Q_(10)为1.52,而刺槐林地仅为1.38.通过单库一级动力学方程拟合可知刺槐林地和坡耕地土壤矿化潜力Cp分别在2.02~4.32g·kg^(-1)和1.25~3.17g·kg^(-1)之间,即刺槐林的矿化潜力更高.培养期内各种活性有机碳组分含量变化规律一致,均表现为随时间延长而下降,且刺槐林地大于坡耕地,土壤累计碳释放量与MBC和DOC含量均呈显著正相关关系(P<0.05),Q_(10)(15~25℃)与SOC、EOC含量和SWC均呈线性关系(P<0.05).研究结果可为气候变化下黄土丘陵区土壤碳固存研究提供一定参考.In order to explore the characteristics of organic carbon mineralization and the variation law of organic carbon components of an artificial forest in a loess hilly area,an artificial Robinia pseudoacacia forest restored for 13 years and the adjacent slope farmland were selected as the research objects,and indoor culture experiments under three different temperature treatments(15,25,and 35℃)were carried out.The results indicated that the mineralization rate of soil organic carbon decreased sharply at first and then stabilized.The cumulative release of organic carbon increased rapidly in the initial stage of culture and gradually slowed in the later stage.Soil organic carbon mineralization in sloping farmland was more sensitive to temperature change,and its temperature sensitivity coefficient Q_(10)was 1.52,whereas that in R.pseudoacacia forest land was only 1.38.According to the fitting of the single reservoir first-order dynamic equation,the soil mineralization potential CPof R.pseudoacacia forest land and slope farmland was between 2.02-4.32 g·kg^(-1)and 1.25-3.17 g·kg^(-1),respectively,that is,the mineralization potential of the R.pseudoacacia forest was higher.During the cultivation period,the content of various active organic carbon components decreased with time,and that in the R.pseudoacacia forest land was greater than that in the slope land.The cumulative carbon release of soil was significantly positively correlated with the contents of MBC and DOC(P<0.05),and Q_(10)(15-25℃)was negatively correlated with the contents of SOC,EOC,and SWC(P<0.05).These results could provide some reference for the study of soil carbon sequestration in loess hilly regions under climate change.

关 键 词：刺槐林 矿化 温度 温度敏感性系数(Q_(10)) 有机碳组分 

分 类 号：X144[环境科学与工程—环境科学]