西北林学院学报2025，Vol.40Issue(4)：1-8,20,9.DOI:10.3969/j.issn.1001-7461.2025.04.01
基于采伐空间单元的华北落叶松邻近木径向生长研究
Study on Radial Growth of Adjacent Trees of Larix principis-rupprechtii Based on the Logging Space Unit
摘要
Abstract
Taking Larix principis-rupprechtii plantation as the research object,based on the cutting space unit composed of cutting tree and its surrounding adjacent tree,the effects of cutting space unit size and spatial parameters on the radial growth of adjacent tree before and after cutting were explored.It is of great significance for the rational management and protection of Larix principis-rupprechtii,and provides refer-ence for further scientific research.The sample plot survey was carried out before harvesting.After harves-ting,105 adjacent trees around the harvested tree were sampled by micro-core method to measure their ra-dial growth.The results show that:The average spatial structure parameters of adjacent trees in each cut-ting space unit changed after cutting,and the angle scale increased to 0.5,while the size ratio and competi-tion index decreased.The radial growth therefore changes.From 2018 to 2022,the average annual radial growth of adjacent trees was 476.92 μm,472.57 μm,427.34 μm,605.12 μm and 782.90 μm,respectively.The average annual radial growth in the two years before tending felling(2018-2019)was 474.74 μm and the average annual radial growth in the two years after tending felling(2021-2022)was 694.01 μm.The radial growth before tending felling showed a downward trend,and the radial growth after tending felling was significantly higher than that before tending felling.There was a significant difference in the radial growth rate of adjacent trees in different logging space units(P＜0.05),and the average growth rate of ad-jacent trees was 54.66％.The average growth rate of adjacent trees in the smallest logging space unit(0.55 m2)was 75.93％,and the average growth rate of adjacent trees in the largest logging space unit(12.00 m2)was 26.03％.The average radial growth rate of adjacent trees with logging space unit area＜10 m2 was significantly higher than that of adjacent trees with area＞10 m2.There were significant differ-ences in the radial growth rate of adjacent trees before logging(P＜0.05);After cutting,the competition intensity of the adjacent tree itself is divided into three levels,Low(CI＜2.21),Medium(2.21 ≤CI≤3.35)and High(CI＞3.35).The corresponding average radial growth increments were 235.58 μm,223.26 μm and 106.19 μm,respectively.The average growth change rates of adjacent trees were 51.5％,75.9％and 98.25％,respectively.All adjacent trees had different degrees of growth release,mild release,moderate release and severe release,accounting for 16％,20％and 21％,respectively.It can be seen that thinning reduces the intensity of competition,increases the radial growth rate,and results in growth release.关键词
采伐空间单元/邻近木/生长率/微树芯法Key words
harvesting space unit/adjacent tree/growth rate/micro-tree-core method分类
农业科技引用本文复制引用
梁春玲,王玲,杨华,贺丹妮..基于采伐空间单元的华北落叶松邻近木径向生长研究[J].西北林学院学报,2025,40(4):1-8,20,9.基金项目
国家林业与草原局应急"揭榜挂帅"项目(202303). （202303）
