辽东山区不同密度落叶松人工幼龄林林木生长和土壤养分特性  

Study on the forest growth and soil nutrient characteristics of Larix spp.plantations with different densities in mountainous area of Liaodong

作　　者：郑颖[1] 冯健[1] 于世河[1] 卜鹏图[1] 王月婵[1] 黄夏[1] 郑璐 ZHENG Ying;FENG Jian;YU Shihe;BU Pengtu;WANG Yuechan;HUANG Xia;ZHENG Lu(Liaoning Academy of Forestry Sciences,Shenyang 110032,Liaoning,China;The Agriculture and Forestry Research Institute in Dryland of Liaoning Province,Chaoyang 122000,Liaoning,China)

机构地区：[1]辽宁省林业科学研究院,辽宁沈阳110032 [2]辽宁省旱地农林研究所,辽宁朝阳122000

出　　处：《中南林业科技大学学报》2022年第1期94-103,共10页Journal of Central South University of Forestry & Technology

基　　金：“十三五”国家重点研发计划项目子课题(2017YFD060040103);国家自然科学基金项目(31971652);辽宁省农业科学院基本科研业务费计划项目(2021GR2913)。

摘　　要：【目的】探究落叶松人工林生长和土壤特性与初植密度的关系,为辽东山区落叶松人工林的合理经营提供科学依据。【方法】以辽宁省清原大孤家林场内3种初植密度(1600、2500、3300株/hm;)的15年生落叶松人工林为研究对象,基于林木生长指标和土壤养分指标等数据,分析初植密度对林木生长和土壤特性的影响。【结果】林分平均胸径、树高、冠幅和单株材积均随初植密度增大而减小,而蓄积量和高径比则随密度增大而增大,密度对树高影响很小。低密度林分胸径、冠幅和单株材积比高密度分别高出了21.5%、21.4%、47.2%,而蓄积量则表现为高密度比低密度高出64.8%。在不同土层间,除了全钾外,落叶松人工林土壤养分总体表现为随土层加深而降低的规律,而pH值则相反;在不同初植密度间,不同土壤养分变化趋势不尽相同,更多的土壤养分在高密度(3300株/hm;)或低密度(1600株/hm;)林分达到最大。在0~20 cm土层中,铵态氮、含水率和pH值以初植密度为1600株/hm^(2)最高,当株数密度为2500株/hm;时pH值最低,呈现明显的酸化趋势,当密度增加到3300株/hm^(2)时,硝态氮、全磷、速效钾、全钾、全氮、有机质和有效磷含量最高;在20~40 cm土层中,硝态氮、pH值、全钾、有效磷以1600株/hm^(2)最高,铵态氮、含水率以2500株/hm^(2)最高,当密度增加到3300株/hm^(2)时,全氮、全磷、速效钾、有机质含量最高。从不同土层看,在0~20 cm土层的全磷、有效磷、铵态氮与林木生长指标关系更为密切,而在20~40 cm土层的速效钾与林木生长指标关系更为密切。从不同初植密度看,密度为2500株/hm^(2)时,林木胸径、树高、单株材积与氮、磷含量关系密切;密度为3300株/hm^(2)时,林木树高、单株材积与氮磷钾含量呈正相关,而蓄积量与pH值呈显著负相关。【结论】初植密度与林木生长和林地土壤特性密切相关,同其他初植密度�【Objective】This study was designed to clarify the relationship between the growth of larch plantations and soil characteristics as well as initial planting densities,in order to provide a scientific basis for the rational management of larch plantations in the mountainous area of eastern Liaoning.【Method】The 15-year old larch plantations with 3 different primary planting densities(1600,2500 and 3300 plants/hm^(2))in Dagujia forest farm,Qingyuan,Liaoning province were used as the research objects.Based on the growth and soil nutrient indexes of the forest,the effects of initial planting densities on forest growth and soil characteristics were analyzed.【Result】The stand growth characteristics showed that the average DBH,tree height,crown width and volume per tree decreased,while the stock volume and height-diameter ratios increased with the increase of initial planting density.The density had little effect on tree height.The DBH,crown width and volume per plant of low-density stands were 12.1%,17.6%and 32.1%higher than those of high-density stands,respectively,while the stock volume of high-density stands was 39.3%higher than the low-density.The soil nutrients in Larix chinensis plantations decreased with soil depth deepening,except total potassium,while the pH values was the opposite.The variation trends of soil nutrients were different among different initial planting densities,and soil nutrients reached the maximum in high-density(3300 plants/hm^(2))or low-density(1600 plants/hm^(2))stands.In the 0-20 cm soil layer,the ammonium nitrogen,water content and pH value were the highest when the initial planting density was 1600 plants/hm^(2).The pH value was the lowest when the density was 2500 plants/hm^(2),showing an obvious acidification trend.When the planting density increased to 3300 plants/hm^(2),the contents of nitrate nitrogen,total phosphorus,available potassium,total potassium,total nitrogen,organic matter and available phosphorus were the highest.In the 20-40 cm soil layer,nitrate nitrogen,pH v

关 键 词：落叶松人工林 初植密度 林木生长 土壤特性 

分 类 号：S718.516[农业科学—林学]