造林密度对楠木幼龄林生长、土壤理化性质与酶活性的影响  

Effects of planting density on growth,soil physical and chemical properties and enzyme activities in young Phoebe zhennan plantation

作　　者：陈宇[1] 庞涛 瞿相 彭建[1] 杨汉波 代林利 辜云杰[1] CHEN Yu;PANG Tao;QU Xiang;PENG JIan;YANG Hanbo;DAI Linli;GU Yunjie(Ecological Restoration and Conservation on Forest and Wetland Key Laboratory of Sichuan Province,Sichuan Academy of Forestry,Chengdu 610081,China;Forestry Station of Sichuan Province,Chengdu 614801,China;Sichuan Provincial Key Laboratory of Ecological Forestry Engineering on the Upper Reaches of the Yangtze River&National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River&Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base,Institute of Ecology&Forestry,Sichuan Agricultural University,Chengdu 611130,China)

机构地区：[1]四川省林业科学研究院,森林和湿地生态恢复与保育四川重点实验室,四川成都610081 [2]四川省林业工作总站,四川成都614801 [3]长江上游林业生态工程四川省重点实验室,长江上游森林资源保育与生态安全国家林业和草原局重点实验室,华西雨屏区人工林生态系统研究长期科研基地,四川农业大学,生态林业研究所,四川成都611130

出　　处：《四川林业科技》2024年第3期9-20,共12页Journal of Sichuan Forestry Science and Technology

基　　金：世行贷款长江上游森林生态系统恢复项目(2019-510000-02-01-400761)科技成果推广或科研课题研究项目“珍贵用材树种良种繁育与造林关键技术研究与示范”及“四川珍稀树种种质资源收集及良种选育研究”。

摘　　要：探究造林密度对楠木人工林早期林木生长、土壤理化性质及酶活性的影响,为楠木人工林地力维持和可持续经营提供理论依据,以3种(D1:667株/hm^(2)、D2:833株/hm^(2)和D3:1111株/hm^(2))不同造林密度的6年生楠木人工林为研究对象,调查林木树高、胸径等生长性状,测定不同土层(0<~10、10<~20和20<~30 cm)土壤理化性质及酶活性,分析楠木人工林树木生长、土壤理化性质和酶活性对造林密度的早期响应。结果表明:随造林密度的增加,楠木人工林平均胸径、材积和树冠投影面积均随造林密度的增加逐渐降低,其中D1密度林分显著高于D2和D3密度林分,表明相对低的造林密度更利于楠木人工林材积的积累。造林密度对土壤硝态氮具有显著影响(P<0.01),造林密度、土层深度均对土壤pH、全氮具有显著影响(P<0.01)。楠木人工林土壤呈弱碱性,同一土层,随着林分密度增加,土壤pH、含水率呈降低趋势,而土壤有机碳含量则呈逐渐升高的趋势。随着土层深度的增加,土壤全氮、硝态氮、铵态氮、全磷含量下降,表明楠木人工林土壤养分具有明显的“表聚”现象;同一土层中,D1密度楠木人工林脲酶、蔗糖酶活性最强,蔗糖酶活性随着造林密度的增加而降低;对树木生长、土壤质量的密度效应分别进行综合分析发现,楠木人工林树木生长和土壤质量综合指数分别以D1和D2密度林分最大,分别为0.61和0.56,说明相对较低的造林密度对于树木生长以及土壤质量改善有一定作用。因此,建议对6年生楠木人工林保留密度应不高于833株/hm^(2),更有利于改善土壤质量和促进树木的生长。The effects of planting density on the early growth,soil physicochemical properties and enzyme activity of Phoebe zhennan plantation were explored,which provided theoretical basis for maintaining soil fertility and sustainable management of P.zhennan plantation.The 6-year-old P.zhennan plantation with three different planting densities(D1:667 trees/hm^(2),D2:833 trees/hm^(2),and D3:1111 trees/hm^(2))was selected as the research object.The growth characteristics such as tree height and diameter at breast height were investigated,and soil physicochemical properties and enzyme activity in different soil layers(0-10 cm,10-20 cm,and 20-30 cm)were measured.The early response of tree growth,soil physicochemical properties,and enzyme activity to planting density in P.zhennan plantation were analyzed.The results showed that with the increase of planting density,the average DBH,wood volume,and crown projection area of P.zhennan plantation decreased gradually.The D1 density stand was significantly higher than that of D2 and D3 stands,indicating that relatively low planting density was more conducive to the accumulation of wood volume in P.zhennan plantation.Planting density had a significant effect on soil nitrate nitrogen(P˂0.01),and planting density and soil depth had significant effects on soil pH and total nitrogen(P˂0.01).Soil of P.zhennan plantation was weakly alkaline.In the same soil layer,with the increase of stand density,soil pH and moisture content decreased,while soil organic carbon content gradually increased.With the increase of soil depth,soil total nitrogen,nitrate nitrogen,ammonium nitrogen,and total phosphorus content gradually decreased,indicating a significant"surface aggregation"phenomenon in the soil of P.zhennan plantation.In the same soil layer,the urease and sucrase activities of P.zhennan plantation with D1 density were the strongest,and the sucrase activities decreased with the increase of planting density.Comprehensive analysis of density effects on tree growth and soil quality showed that the

关 键 词：造林密度 楠木 人工林 生长性状 土壤理化性质 土壤酶 

分 类 号：S792.24[农业科学—林木遗传育种] S714[农业科学—林学]