摘要
【目的】研究甘肃南部不同密度云杉人工幼龄林的径级结构、树高结构、空间分布和土壤理化特征,探讨林分最佳留存密度,以期为人工云杉林的营建与可持续经营提供科学依据。【方法】采用固定样地调查、角尺度研究及分层取样分析的方法,设置7种不同林分密度(850,1 060,1 350,1 550,1 750,2 300和3 000株·hm^(-2))人工云杉幼龄林(林龄30～40年)样地28块,测定径级结构、树高结构、冠幅、角尺度等林分结构以及土壤密度、土壤饱和持水量、田间持水量、毛管持水量、总孔隙度、毛管孔隙度、有机质、全氮、全磷、全钾、速效氮、速效磷和速效钾等土壤理化性质,计算各指标的平均值、标准差,并进行各指标间的差异性检验。【结果】林分的平均胸径和冠幅随林分密度增大而减小,平均树高则随林分密度的增大先增大后减小;不同密度林分径级结构和高度结构均呈现正态分布的单峰曲线,峰值径级随着密度增大而逐渐减小,胸径处于12～24 cm树木的频度较高而DBH>24 cm和DBH<12 cm的树木很少;采用角尺度研究林分空间分布格局,林分角尺度值随着林分密度增大而逐渐减小,林分密度≤1 550株·hm^(-2)时为随机分布,林分密度>1 550株·hm^(-2)时为均匀分布;林分密度是影响云杉人工林土壤理化性质(尤其是土壤有机质含量和总孔隙度)的关键因子;中密度(1 550株·hm^(-2 ))时土壤养分含量总体较高,土壤密度最小,表层(0～20 cm)土壤饱和持水量、毛管持水量、田间持水量和总孔隙度都最大,土壤理化特性均优于过密或过疏的林分。【结论】林分密度与林分结构特征以及土壤理化性质密切相关,中等密度(1 550株·hm^(-2))利于保持较好的林分结构特征和土壤理化性质,是甘肃南部云杉人工幼龄林分的最佳留存密度。
【Objective】 In this research, we have studied the diameter structure, tree height structure, spatial distribution and soil physicochemical characteristics of young plantation of Picea asperata with different densities and investigated the optimum stand retention density of plantation in Southern Gansu, the purpose of these efforts were to provide scientific basis for the construction and sustainable management of Picea asperata plantation.【Method】 In this study, 28 plots within 7 levels of tree densities （850, 1 060, 1 350, 1 550, 1 750, 2 300, 3 000 individual ·hm^-2 ） in young plantation of Picea asperata were studied by method of sample plot investigation, uniform angle index and stratified sampling analysis, determined the diameter class structure, tree height structure, uniform angle index, soil density, saturated moisture, field capacity, capillary capacity, total prosity, capillary prosity, organic matter, total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus and available potassium etc.,calculated the average value of each index, standard deviation, and the differences between the various indices.【Result】 The growth of the average DBH and average crown width all decreased along with the increase of density, the average height increased at first then decreased with the increased of density.The diameter and height structure with different densities were unimodal curves belong to normal distribution, the peak diameter gradually decreases with the increase of density, the frequency of tree medium diameter
（DBH：12-24 cm） were much more than diameter （DBH〉24 cm） and （DBH〈12 cm）.Using spatial structure parameters of the uniform angle index to study the spatial structure characteristics of forest, the uniform angle index gradually decreases with the increase of density, the stand structure was random distribution when the stand density was less than 1 550 individual ·hm^-2 and when the stand density was greater than 1 550 individual ·hm^-
作者
冯宜明
李毅
曹秀文
刘锦乾
齐瑞
赵阳
陈学龙
Feng Yiming;Li Yi;Cao Xiuwen;Liu Jinqian;Qi Rui;Zhao Yang;Chen Xuelong(College of Forestry,Gansu Agricultural University Lanzhou 730070;Research Institute of Forestry,Bailongjiang Forestry Administration Lanzhou 730070;Gansu Bailongjiang National Forest Ecosystem Research Station Wudu 746000)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2018年第10期20-30,共11页
Scientia Silvae Sinicae
基金
国家自然科学基金项目(31360205)
甘肃省科技支撑计划项目(144FKCK072)
甘肃林业科技项目(2017kj041)
关键词
云杉人工林
林分密度
林分结构
土壤性质
径级结构
高度结构
空间分布格局
Picea asperata plantation
tree density
stand structure
soil property
diameter structure
height structure
spatial distribution pattern
