川西次生灌丛和不同类型人工林对土壤养分的影响  

Effect of shrubland and reforestation with different tree species on soil nutrients in western Sichuan

作　　者：陈文静[1,2] 祁凯斌 黄俊胜[1,2] 杨婷惠 包维楷[1] 庞学勇 

机构地区：[1]中国科学院山地生态恢复与生物资源利用重点实验室,生态恢复与生物多样性保育四川省重点实验室,中国科学院成都生物研究所,成都610041 [2]中国科学院大学,北京100049

出　　处：《应用与环境生物学报》2017年第6期1081-1088,共8页Chinese Journal of Applied and Environmental Biology

基　　金：国家重点研发计划项目(2017YFC0505002);国家自然科学基金项目(31770658);四川省科技支撑项目(2017SZ0038);应用基础研究和软科学项目(2009SZ0061,2009JY0107,2009ZR0152)资助~~

摘　　要：为评价不同树种造林对土壤养分循环的影响,以落叶阔叶灌丛为对照,比较研究川西亚高山造林恢复28年后4种人工林(连香树Cercidiphyllum japonicum、油松Pinus tabulaeformis、落叶松Larix kaempferi和华山松Pinus armandii)土壤有机质(SOM)、可溶性有机碳(DOC)、可溶性有机氮(DON)及全氮(TN)、全磷(TP)、土壤铵态氮(NH4+-N)和硝态氮(NO3--N)的含量,结合林地凋落物贮量及细根生物量等参数,试图揭示不同人工林土壤养分差异化的影响因素.结果显示:人工造林影响土壤的养分循环,与落叶灌丛林地相比,除连香树样地TP密度及2015年10-20 cm的SOM、TN密度外,落叶人工林土壤养分基本呈下降趋势.除华山松样地的可溶性有机质(DOC、DON)外,油松及华山松人工林土壤地力的退化趋势更甚于落叶人工林样地,其土壤有机质含量、TN、TP密度、可溶性有机质及速效养分均呈不同程度的下降.不同人工林间土壤养分的差异性与不同树种的凋落物、细根、土壤容重及涵水能力差异化有关.综上所述,人工林林分结构单一导致小气候恶化、凋落物分解缓慢是造成土壤养分循环功能下降的重要原因;选择有利于养分循环的阔叶树种营造针阔混交林以改善林分结构和土壤环境条件,可促进土壤养分的循环.Reforestation is a key forest management practice for restoring soil nutrient contents of degraded ecosystems. The conversion from shrubland to plantations can lead to dynamic variations in soil nutrient content, and these changes are dependent on tree species and forest management practices. To evaluate differences in soil organic matter （SOM）, dissolved organic carbon, dissolved organic nitrogen and nitrogen density, phosphorus density, NH4＋-N, and NO3？-N among different vegetation types, four pure plantation （28-year-old） stands with dominant tree species （e.g., Cercidiphyllum japonicum, Pinus tabulaeformis, Larix kaempferi, and P. armandii） were selected; a nature broad-leaf shrubland was selected as a control. The four plantations substituting for coppice were cultivated under similar site conditions and with identical planting and management patterns. In 2013 and 2015, we measured the soil total and available parameters and the storage of litter and fine root biomass. Our objective was to evaluate the dynamics and differences in soil nutrients and discern the influencing factors after conversion from shrubland to plantations. Our results indicated that reforestation significantly influenced the cycling of soil nutrient content. In comparison with native broad-leaf shrubland, soil organic matter and nutrient content in L. kaempferi and C. japonicum plantations were generally lower; the exceptions were phosphorus density and soil organic matter （SOM）, and nitrogen density at a depth of 10–20 cm in C. japonicum plantations in 2015. Different species contributed to variations in soil nutrient content. In comparison with C. japonicum and L. kaempferi plantations, evergreen pure coniferous plantations （i.e., P. armandii and P. tabulaeformis） generally led to a higher deficit of soil nutrient content; the exception was the dissolved organic matter in P. armandii plantations. The differences in soil nutrient content were mainly influenced by the litter, fine root biomass, soil bulk density

关 键 词：造林 人工林 树种 土壤养分 凋落物 细根 

分 类 号：S714.8[农业科学—林学]