鸡公山落叶阔叶林土壤呼吸的坡向间差异及其影响因子  

Variations in soil respiration and its impact factors among aspects in deciduous broadleaf forest in Jigong Mountain

作　　者：胡晓杰 田慧敏 郝艺晴 刘彦春[1] 琚煜熙 张旺[3] HU Xiaojie;TIAN Huimin;HAO Yiqing;LIU Yanchun;JU Yuxi;ZHANG Wang(College of Life Sciences,Henan University,Kaifeng 475004,China;Jigongshan Natural Reserve Administration,Xinyang 464133,China;Nanwan Forest Farm,Xinyang 464031,China)

机构地区：[1]河南大学生命科学学院,河南开封475004 [2]信阳市鸡公山国家级自然保护区管理局,河南信阳464133 [3]河南省信阳市南湾实验林场,河南信阳464031

出　　处：《甘肃农业大学学报》2021年第6期104-110,118,共8页Journal of Gansu Agricultural University

基　　金：国家自然科学基金项目(31971454);河南省高等学校青年骨干教师培养计划项目(2020)。

摘　　要：【目的】揭示坡向对森林土壤呼吸空间异质性的影响规律及调节因子.【方法】在河南鸡公山栎类落叶阔叶林内,按照东北、东南、西北和西南4个坡向各布设6个试验样地,利用Li-8100土壤碳通量分析系统测定1~12月的土壤呼吸,并采集土壤样品分析了土壤有机碳和总氮含量.【结果】土壤呼吸在不同坡向间存在显著差异,年均值大小依次表现为:西北(0.97μmol/(m^(2)·s))<东北(1.16μmol/(m^(2)·s))<西南(1.35μmol/(m^(2)·s))<东南(2.30μmol/(m^(2)·s)).然而,坡向并未改变土壤呼吸的温度敏感性.多元逐步回归分析显示土壤温度是调节不同坡向土壤呼吸差异的主要环境因子.土壤总氮和土壤湿度是调控西北坡和东南坡土壤呼吸的重要因子.【结论】量化森林土壤呼吸的坡向间差异及其环境调控规律有助于加深小地形影响下的土壤碳排放规律的认识及提高陆地碳循环的估算精度.【Objective】Revealing the responses of spatial heterogeneity of soil respiration to aspect and its potential mechanism.【Method】Six experimental plots were established at each aspects(northeast,southeast,northwest,and southwest)in an oak-dominated deciduous broad-leaved forest in Jigong Mountain.Soil respiration was measured from January to December using Li-8100 Soil Carbon Fluxes Analyzer,and soil organic carbon and total nitrogen were also investigated.【Result】Significant differences in soil respiration were found among different aspects,with the mean annual values showing the following order:northwest(0.9μmol/m^(2)·s)<northeast(1.16μmol/m^(2)·s)<southwest(1.35μmol/m^(2)·s)<southeast(2.30μmol/m^(2)·s).However,aspect did not affect the temperature sensitivity of soil respiration.Multiple stepwise regression analysis showed that soil temperature was the main environmental factor affecting soil respiration among different aspects,and soil total nitrogen and moisture influenced the variation of soil respiration in northwest and southeast aspects,respectively.【Conclusion】Quantifying the variations in forest soil respiration among different aspects and clarifying the environmental regulation can improve our understanding on topography-depended soil carbon emission and enhance the estimation accuracy of terrestrial carbon cycle.

关 键 词：空间异质性 土壤呼吸 坡向 阔叶林 

分 类 号：S714[农业科学—林学]