间伐对秦岭松栎混交林土壤异养呼吸的影响  

Effects of thinning on soil heterotrophic respiration of oak-pine mixed forests in Qinling Mountains

作　　者：曹立 王维枫 马雪红 王祥福 李玉 李丽[2,5] 于水强 CAO Li;WANG Weifeng;MA Xuehong;WANG Xiangfu;LI Yu;LI Li;YU Shuiqiang(College of Ecology and Environment,Nanjing Forestry University,Nanjing 10037,Jiangsu,China;Co-Innovation Center for the Sustainable Forestry in South China,Nanjing Forestry University,Nanjing 210037,Jiangsu,China;College of Life Science,Nanjing Forestry University,Nanjing 210037,Jiangsu,China;Key Laboratory National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions,Northwest Surveying and Planning Institute of National Forestry and Grassland Administration,Xi’an 710048,Shaanxi,China;Bamboo Research Institute,Nanjing Forestry University,Nanjing 210037,Jiangsu,China)

机构地区：[1]南京林业大学生态与环境学院,江苏南京210037 [2]南京林业大学南方现代林业协同创新中心,江苏南京210037 [3]南京林业大学生命科学学院,江苏南京210037 [4]国家林业和草原局西北调查规划院旱区生态水文与灾害防治国家林业局重点实验室,陕西西安710048 [5]南京林业大学竹类研究所,江苏南京210037

出　　处：《浙江农林大学学报》2024年第1期22-29,共8页Journal of Zhejiang A&F University

基　　金：国家自然科学基金资助项目(32071763);国家林业和草原局西北调查规划院2021年科技创新项目(XBJ-KJCX-2021-15)。

摘　　要：【目的】研究间伐对秦岭松栎混交林土壤异养呼吸的影响,可深入了解该地区间伐对森林土壤异养呼吸造成的碳损失情况,为研究区森林经营碳汇提供科学依据。【方法】以秦岭松栎混交林为研究对象,对未间伐样地(ck)、间伐4 a、间伐12 a的样地采用静态箱-气相色谱法监测生长季土壤异养呼吸速率的月变化,并计算各处理异养呼吸的温度敏感性(Q_(10))。【结果】①相比ck,间伐4 a、间伐12 a的样地土壤微生物生物量碳均显著下降(P<0.05),土壤pH均显著上升(P<0.05),土壤总有机碳质量分数在间伐4 a的样地中显著下降(P<0.05)。间伐12 a样地的理化指标相比间伐4 a的样地更接近ck。②生长季土壤异养呼吸呈现“双峰型”变化规律,峰值分别出现在6和10月。异养呼吸累计通量在间伐后略有上升但不显著,不同样地从大到小依次为间伐12 a、间伐4 a、ck。③土壤温度与异养呼吸呈极显著指数正相关(P<0.001);间伐后Q_(10)降低,不同样地Q_(10)从大到小依次为ck、间伐12 a、间伐4 a。【结论】土壤温度是影响松栎混交林异养呼吸的关键因素。间伐没有导致秦岭松栎混交林异养呼吸通量显著增大。[Objective]This study,with an investigation of the effects of thinning on soil heterotrophic respiration in oak-pine mixed forests in the Qinling Mountains,is aimed to better understand the carbon loss caused by forest soil heterotrophic respiration under thinning treatments,providing a scientific basis for forest management decisions in the study area.[Method]The static chamber-gas chromatography technique was employed to monitor the variations of soil heterotrophic respiration flux in the growing season for the unthinned plots(4 replicates,ck)and the thinning plots(4 replicates)4 and 12 years ago(4 a and 12 a),respectively.The temperature sensitivities(Q10)of heterotrophic respiration were also calculated.[Result](1)There was a remarkable decrease in the soil microbial biomass carbon content(P<0.05),but a significant increase in the the soil pH(P<0.05)in both 4 a and 12 a compared to ck,while the decrease in the soil organic carbon content of 4 a after thinning was significant(P<0.05).Generally,the soil physical and chemical index in 12 a were closer to that in the ck than the 4 a treatment.(2)The soil heterotrophic respiration during the growing season showed a“bimodal”pattern,and the peaks appeared in June and October,respectively.However the cumulative heterotrophic respiration increased after thinning but not significantly,with the order from large to small being 12 a>4 a>ck.(3)The soil temperature was significantly and exponentially correlated with the soil heterotrophic respiration(P<0.05).The temperature sensitivities Q10 decreased after thinning,with the order from large to small being ck>12 a>4 a.[Conclusion]The soil temperature is a key factor affecting soil heterotrophic respiration in oak-pine mixed forests and the thinning treatment do not promote soil heterotrophic respiration of the oak-pine mixed forests in the growing season at the Qinling Mountains.

关 键 词：秦岭南坡 森林抚育 土壤有机碳分解 土壤呼吸 

分 类 号：S714[农业科学—林学]