不同处理方式下湿地松人工林土壤呼吸及温度敏感性变化  

Changes of Soil Respiration and Temperature Sensitivity in Pinus elliottii Plantation Under Different Treatments

作　　者：沈健 何宗明[1,2] 董强 郜士垒[1,2] 林宇 石焱 SHEN Jian;HE Zong-ming;DONG Qiang;GAO Shi-lei;LIN Yu;SHI Yan(College of Forestry,Fujian Agriculture and Forestry University,Fuzhou 350002,Fujian,China;Engineering Research Center of Chinese Fir,National Forestry and Grassland Administration,Fuzhou 350002,Fujian,China;Minhou Baisha State-Owned Forest Farm of Fujian Province,Fuzhou 350100,Fujian,China;National Academy of Forestry and Grassland Administration,Beijing 102600,China)

机构地区：[1]福建农林大学林学院,福建福州350002 [2]国家林业和草原局杉木工程技术研究中心,福建福州350002 [3]闽侯白沙国有林场,福建福州350100 [4]国家林业和草原局管理干部学院,北京102600

出　　处：《西北林学院学报》2023年第5期10-18,共9页Journal of Northwest Forestry University

基　　金：福建省林业科技基目([2022]52号)。

摘　　要：研究碳输入处理对沿海地区湿地松人工林土壤碳排放的影响,分析不同碳输入下各组分(植物根系、凋落物层及矿质土壤)的呼吸速率及其贡献,为人为干扰下滨海沙地碳循环模式和未来沿海地区气候变化提供参考。在福建省长乐大鹤国有防护林场的湿地松人工林中,采用随机区组试验改变湿地松人工林地上、地下碳输入方式,设置对照(SC)、去除根系(SR)、去除凋落物(SL)、环割(SG)、环割+去根(SGR)、环割+去凋落物(SGL)6个处理,采用开路式碳通量测定系统Li-8100测定不同处理样地每月的土壤呼吸速率、土壤温度和土壤湿度,并计算不同呼吸组分的速率和温度敏感性(Q_(10))。结果表明:1)观测期间,不同处理土壤呼吸年通量由大到小依次为对照(23.82 t·hm^(-2))、环割(20.04 t·hm^(-2))、去除凋落物(19.74 t·hm^(-2))、去除根系(14.4 t·hm^(-2))、环割+去凋落物(14.39 t·hm^(-2))、环割+去根(14 t·hm^(-2)),与对照相比碳输入减少后土壤呼吸均有所降低。2)不同处理间的土壤湿度差异极显著(P<0.01),土壤温度差异不显著(P>0.05)。3)湿地松林地异养呼吸在总呼吸中占比60.4%,自养呼吸占比39.6%。各组分呼吸速率对总呼吸速率的贡献率分别为矿质土壤呼吸(43.3%)、根系呼吸(39.6%)、凋落物层呼吸(17.2%)。4)不同处理使土壤呼吸温度敏感性(Q_(10))均有所升高(除环割+去根处理),各处理Q_(10)依次为环割+去凋落物>去除凋落物>去除根系>环割>环割+去根=对照。不同碳输入处理对土壤CO_(2)排放有明显影响,碳输入方式是影响森林土壤呼吸速率的重要因子。The objectives of this study were to study the effects of carbon input on soil carbon emissions from Pinus elliottii plantations in coastal areas,and to analyze the respiration rates of each component(plant root,litter layer and mineral soil)and their contributions under different carbon inputs,and to provide a reference for the carbon cycle patterns in coastal sandy areas under anthropogenic disturbance and future climate change in coastal areas.The experiment were carried out from September 2019 to August 2020 in P.elliottii plantation in Dahe State-owned Forest Farm,Changle,Fujian Province,China.A randomized group experiment was adopted to change the above-and below-ground carbon input of P.elliottii plantation in six treatments:control(SC),root-trenching(SR),litter removal(SL),girding(SG),girding+oot-trenching(SGR),and girding+litter removal(SGL),and an open-circuit carbon flux measurement system Li-8100 was used to determine monthly soil respiration,soil temperature,and soil moisture in the sample plots of different treatments,and the rate and temperature sensitivity(Q_(10))of different respiration components were calculated.1)The annual soil respiration fluxes of the different treatments during the observation period were in the order of magnitude SC(23.82)>SG(20.04)>SL(19.74)>SR(14.4)>SGL(14.39)>SGR(14 t·hm^(-2)·a^(-1)),soil respiration decreased after the reduction of carbon input compared with the control.2)The variability of soil moisture was extremely significant(P<0.01),and soil temperature was not significant(P>0.05)among treatments.3)Heterotrophic respiration accounted for 60.4%of the total and autotrophic respiration accounted for 39.6%in the P.elliottii plantation.The contribution of the respiration rates of individual component to the total respiration rate were mineral soil respiration(43.3%),root respiration(39.6%),and litter respiration(17.2%).4)All the treatments increased the temperature sensitivity of soil respiration(Q_(10))(except girding+root-trenching treatment),and the order of Q_(10

关 键 词：碳输入 碳排放 自养呼吸 异养呼吸 温度敏感性 

分 类 号：S714.5[农业科学—林学]