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机构地区:[1]北京林业大学林学院,省部共建森林培育与保护教育部重点实验室,北京100083
出 处:《西北农林科技大学学报(自然科学版)》2012年第12期73-78,共6页Journal of Northwest A&F University(Natural Science Edition)
基 金:林业公益性行业科研专项(20100400203);高等学校博士点基金项目(20090014110013)
摘 要:【目的】分析北京十三陵林场人工侧柏林的天然更新情况,为北京人工侧柏林的天然更新研究提供依据。【方法】采用标准地调查法,对北京十三陵林场人工侧柏林林分的天然更新状况进行调查,并运用灰色关联法对影响天然更新的8个因子进行定性和定量分析。【结果】人工侧柏林林分中,各树种更新幼苗在≤30cm和>30~≤50cm高度级的更新等级均为不良,在>50cm高度级的更新等级为中等;林分中阔叶树种的更新能力强于针叶树种,优势树种侧柏幼苗更新密度和频度分别为538株/hm2和13.8%;影响侧柏林更新的8个因子的关联度排序为:海拔>坡向>土壤厚度>坡位>林分密度>坡度>灌草盖度>枯落物厚度。【结论】北京十三陵林场人工侧柏林更新状况不佳,难以完成天然更新。在一定范围内,海拔越低,更新株数越多;在南和西南坡向上,光照条件较好,有利于林分的天然更新。【Objective】 This study analyzed the natural regeneration of Platycladus orientalis stands in Shisanling Forest Farm,to better understand the natural regeneration of P.orientalis in Beijing.【Method】 Standard survey method was utilized to investigate the natural regeneration of stands,and gray correlation method was used to analysis the factors affecting natural regeneration qualitatively and quantitatively.【Result】 The update grades of stand seedlings with heights ≤30 cm and 30-≤50 cm were bad,and that of seedlings with height 50 cm was medium.Update ability of the broad-leaved species was better than conifers.P.orientalis was the dominating species,and the regeneration density and frequency of its seedling were 538 plant/hm2 and 13.8%,respectively.Correlation degrees of eight factors which associated with the natural regeneration of P.orientalis stands ranked as follows: altitudeslope aspectsoil thicknessslope positionstand densitygradientshrub and grass coveragelitter thickness.【Conclusion】 Natural regeneration of artificial P.orientalis stands in Shisanling Forest Farm is bad and it is difficult for them to regenerate naturally.Within a certain range,the lower the altitude,the higher the updated number of trees.The slopes towards south and southwest have more sufficient sunlight and are in favor of natural regeneration.
分 类 号:S754.1[农业科学—森林经理学]
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