马尾松纯林阔叶化改造对土壤碳氮固持的短期效应  

The short-term effects of converting pure Pinus massoniana forests into mixed broadleaved forests on soil carbon and nitrogen sequestration

作　　者：王浩东 陈梦 袁丛军 何爽 丁访军 杨瑞[4] WANG Haodong;CHEN Meng;YUAN Congjun;HE Shuang;DING Fangjun;YANG Rui(Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China,Guizhou Academy of Forestry,Guiyang 550005,Guizhou,China;Guizhou Leigongshan Observation and Research Station for Forest Ecosystem,Leishan 557100,Guizhou,China;Longli Forestry Farm of Guizhou Prorince,Longli 551200,Guizhou,China;College of Forestry,Guizhou University,Guizhou 550025,Guiyang,China)

机构地区：[1]贵州省林业科学研究院西南喀斯特山地生物多样性保护国家林业和草原局重点实验室,贵州贵阳550005 [2]贵州雷公山森林生态系统国家定位观测研究站,贵州雷山557100 [3]贵州省国有龙里林场,贵州龙里551200 [4]贵州大学林学院,贵州贵阳550025

出　　处：《中南林业科技大学学报》2024年第10期126-137,共12页Journal of Central South University of Forestry & Technology

基　　金：贵州省科技计划项目(黔科合服企〔2020〕4010);2023年贵州天然林保护管理补助资金项目“天然林资源保护与修复效益监测”;2023年贵州森林资源管理补助资金项目“贵州人工商品纯林树种结构优化调整对森林碳汇效益提升监测研究”;贵州雷公山森林生态系统国家定位观测研究站项目资助。

摘　　要：【目的】为了解马尾松纯林补植不同阔叶树种对土壤碳库的影响,筛选不同类型的阔叶化改造土壤高效固碳模式。【方法】在贵州省独山县国有林场内选择林分结构相似且具有代表性的马尾松Pinus massoniana人工纯林,经择伐后补植香樟Cinnamomum camphora、楠木Phoebe zhennan、南酸枣Choerospondias axillaris、鹅掌楸Liriodendron chinense阔叶树种8~14 a,以未补植阔叶树的马尾松纯林为对照,分别设置3块样地,共15块,采集0~20、20~40和40~60 cm的土壤,测定土壤理化性质和活性有机碳组分。【结果】补植不同阔叶树种对土壤碳库影响不同,对0~20 cm影响较为显著,对更深层土壤影响较小,0~60 cm的土壤碳储量变化范围约1.39~12.77 kg·m^(-2),其中,马尾松纯林和马尾松+南酸枣林的土壤碳储量较高,分别达到212.35和203.51 kg·m^(-2),马尾松+香樟林土壤碳储量最低,约为100.78 kg·m^(-2);补植阔叶树种后土壤pH值显著降低,而MBC显著增加;在0~20 cm土层,南酸枣+马尾松林土壤有机碳和全氮显著提升;补植阔叶树种后短期内土壤碳储量降低,但土壤氮储量无显著变化;补植楠木后土壤碳库活度和碳库活度指数提升,补植南酸枣后土壤碳库稳定性显著提升。【结论】优先选择叶片中初始木质素/氮值高的落叶阔叶树种能有效提升马尾松纯林土壤碳氮固持能力。马尾松纯林阔叶化改造短期内对土壤氮储量影响较小,土壤碳库一定程度下降后,可能需要15 a以上的恢复期。【Objective】In order to understand the impact of replanting different broad-leaved tree species on soil carbon storage in Pinus massoniana forests,a study was conducted to identify an effective carbon sequestration model for the broadleaf transformation of P.massoniana plantations.【Method】Within the state-owned forest farm in Dushan county,Guizhou province,a representative artificially planted pure forest of P.massoniana with similar forest structure was selected.After selective logging,Cinnamomum camphora,Phoebe zhennan,Choerospondias axillaris,and Liriodendron chinense of broad-leaved tree species were replanted in the same forest plot for 8-14 a.Three plots were designated for each condition,with a total of 15 plots,and soil samples of 0-20,20-40,and 40-60 cm were collected for determination of soil physiochemical properties and active organic carbon components,using the pure forest of P.massoniana without replanting the broad-leaved trees as the control.【Result】Replanting different broad-leaved tree species had varying effects on soil carbon pools,with significant effects on the 0-20 cm soil layer and smaller effects on deeper soil layers.The range of soil carbon storage changes in the 0-60 cm layer was approximately 1.39-12.77 kg·m-2,with the highest soil carbon storage observed in pure forests of P.massoniana and P.massoniana+C.axillaris,reaching 212.35 and 203.51 kg·m-2,respectively,while the P.massoniana and C.camphora forest had the lowest soil carbon storage,approximately 100.78 kg·m-2.Replanting broad-leaved trees significantly reduced soil pH but increased microbial biomass carbon(MBC).In the 0-20 cm soil layer,the soil organic carbon and total nitrogen significantly increased in the P.massoniana+C.axillaris forest.Although soil carbon storage decreased in the short term after replanting broad-leaved trees,soil nitrogen storage did not significantly change.The replanting of P.zhennan significantly increased soil carbon pool activity and carbon pool activity index,while the replanting of

关 键 词：马尾松人工纯林 碳氮固存 补植阔叶树 短期效应 

分 类 号：S714.2[农业科学—林学]