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大兴安岭天然次生林林木补植空间优化

王涛 董灵波 刘兆刚 张凌宇 陈莹

王涛, 董灵波, 刘兆刚, 张凌宇, 陈莹. 大兴安岭天然次生林林木补植空间优化[J]. 北京林业大学学报, 2019, 41(5): 127-136. doi: 10.13332/j.1000-1522.20190025
引用本文: 王涛, 董灵波, 刘兆刚, 张凌宇, 陈莹. 大兴安岭天然次生林林木补植空间优化[J]. 北京林业大学学报, 2019, 41(5): 127-136. doi: 10.13332/j.1000-1522.20190025
Wang Tao, Dong Lingbo, Liu Zhaogang, Zhang Lingyu, Chen Ying. Optimization of replanting space of natural secondary forest in Daxing’anling Mountains of northeastern China[J]. Journal of Beijing Forestry University, 2019, 41(5): 127-136. doi: 10.13332/j.1000-1522.20190025
Citation: Wang Tao, Dong Lingbo, Liu Zhaogang, Zhang Lingyu, Chen Ying. Optimization of replanting space of natural secondary forest in Daxing’anling Mountains of northeastern China[J]. Journal of Beijing Forestry University, 2019, 41(5): 127-136. doi: 10.13332/j.1000-1522.20190025

大兴安岭天然次生林林木补植空间优化

doi: 10.13332/j.1000-1522.20190025
基金项目: 国家重点研发计划项目(2017YFC0504103),黑龙江省森林可持续经营试验示范区建设项目(201522-2)
详细信息
    作者简介:

    王涛。主要研究方向:森林可持续经营。Email:376557961@qq.com 地址:150040 黑龙江省哈尔滨市香坊区和兴路26号东北林业大学林学院

    责任作者:

    刘兆刚,博士,教授。主要研究方向:森林可持续经营。Email:lzg19700602@163.com 地址:同上

  • 中图分类号: S725.71

Optimization of replanting space of natural secondary forest in Daxing’anling Mountains of northeastern China

  • 摘要: 目的为优化林分空间结构,提高现有林分质量,加速森林生态系统恢复,加速大兴安岭地区森林群落向顶级群落演替,确定天然次生林林下补植树种和补植位置,为大兴安岭地区的森林经营提供理论支持和方法。方法本文以大兴安岭地区白桦纯林、落叶松白桦混交及针叶混交3种典型的林分类型为例,在次生林原有天然更新的基础上,利用Voronoi图进行空间单元确定和Voronoi结点边缘校正,并使用反距离插值使林木空间结构参数可视化,预测林分中未含林木区域的空间结构信息,将其作为补植依据,使用熵权法确定各空间结构参数权重,将各空间结构参数插值后图像进行加权叠加,以林分非空间结构为约束条件,优化林分空间结构为目标,探讨次生林林下补植树种和位置。结果(1)选取兴安落叶松为补植树种,各林型幼树补植数量分别为660、1 970、315。(2)补植后白桦纯林样地中白桦幼树幼苗混交度增加为0.52,其他树种幼树幼苗混交度增加为0.51;落叶松白桦混交林中白桦幼树幼苗混交度增加为0.84,其他树种幼树幼苗混交度增加为0.70;针叶混交林中白桦幼树幼苗增加为0.78,其他树种幼树幼苗混交度增加为0.50。(3)补植后各林型样地林下幼树幼苗Voronoi图多边形边数标准差分别为1.31、1.41、1.36,均处于随机分布状态。白桦纯林、落叶松白桦混交林及针叶混交林中落叶松幼树幼苗Voronoi图多边形边数标准差分别为1.27、1.40、1.37,均呈随机分布。结论采伐和补植是两种相反的空间优化方式,将林木空间结构参数进行反距离插值,可以预测林分中无林木区域的空间结构参数值,插值后的图像像元大小可以设定为补植幼树所需要的林地面积大小,依据林分空间结构的优化目标和补植数量的调控目标,提取样地未含林木区域空间参数值,进而确定补植的树种和位置。

     

  • 图  1  Voronoi结构单元

    1081、1082等数字代表单株林木编号。The number of 1081, 1082, etc. in the figure represent individual forest No.

    Figure  1.  Voronoi structural unit

    图  2  落叶松白桦混交林空间结构参数反距离插值

    Figure  2.  Spatial structure parameter IDW of mixed forest of Larix gmelinii and Betula platyphylla

    图  3  V-Heygi指数像元邻域窗口

    Figure  3.  Pixel neighborhood window of V-Heygi index

    图  4  V-Mi像元邻域窗口

    Figure  4.  Pixel neighborhood window of V-Mi

    图  5  V-Ui像元邻域窗口

    Figure  5.  Pixel neighborhood window of V-Ui

    图  6  V-Wi像元邻域窗口

    Figure  6.  Pixel neighborhood window of V-Wi

    图  7  各林型补植区域与补植位置

    Figure  7.  Replanting area and replanting position of each forest type

    图  8  补植前后空间结构参数值比较

    Ⅰ为白桦,Ⅱ为落叶松,Ⅲ为其他树种,Ⅳ林分空间结构参数,样地中白桦和落叶松以外的树种记为其他树种。Ⅰ is Betula platyphylla, Ⅱ is Larix gmelinii, Ⅲ is other tree species, and Ⅳ is the spatial structure parameters of forest stand. The tree species except Betula platyphylla and Larix gmelinii in the sample plot are recorded as other tree species.

    Figure  8.  Comparison of spatial structure parameter values before and after replanting

    表  1  各林型样地基本信息表

    Table  1.   Basic information of sample plots in each forest type

    林型
    Forest type
    树种组成
    Species composition
    海拔
    Elevation/m
    郁闭度
    Canopy density
    坡度
    Slope gradient/(°)
    土壤类型
    Soil type
    平均胸径
    Mean DBH/cm
    平均高
    Mean height/m
    白桦纯林
    Betula platyphylla forest
    10白桦Betula platyphylla
    5660.5 < 5暗棕壤
    Dark brown soil
    12.5 ± 4.213.3 ± 3.4
    落叶松白桦混交林
    Larix gmelinii and Betula platyphylla mixed forest
    6落叶松Larix gmelinii
    4白桦Betula platyphylla
    5460.7 < 5暗棕壤
    Dark brown soil
    13.1 ± 4.713.7 ± 3.5
    针叶混交林
    Larch coniferous mixed forest
    6落叶松Larix gmelinii
    2樟子松Pinus sylvestris var. mongolica
    1云杉Picea abies
    1白桦Betula platyphylla
    4570.66暗棕壤
    Dark brown soil
    10.5 ± 4.411.2 ± 2.9
    下载: 导出CSV

    表  2  各林型样地幼苗幼树信息统计表

    Table  2.   Statistical table of seedlings and saplings in sample plot of each forest type

    林分类型
    Forest type
    树种
    Species
    幼苗 Seedling (H ≤ 30.0 cm)幼树 Sapling (30.0 cm < H & DBH < 5.0 cm)
    地径
    Ground diameter/cm
    树高
    Tree height/cm
    密度/(株·hm2)
    Density/(plant·ha− 1)
    地径
    Ground diameter/cm
    树高
    Tree height/cm
    密度/(株·hm2)
    Density/(plant·ha− 1)
    白桦纯林
    Betula platyphylla forest
    白桦
    Betula platyphylla
    0.719.3631.5185.1802
    落叶松
    Larix gmelinii
    0.324.012.3212.6221
    山杨
    Populus davidiana
    1.8199.51 317
    落叶松白桦混交林
    Larix gmelinii and Betula platyphylla mixed forest
    白桦
    Betula platyphylla
    0.322.191.5172.8142
    落叶松
    Larix gmelinii
    0.316.842.3210.0129
    山杨
    Populus davidiana
    0.620.521.3151.2759
    落叶松
    Larix gmelinii
    0.622.1123.2274.61 013
    云杉
    Picea asperata
    0.315.45461.8117.6975
    针叶混交林
    Larch coniferous mixed forest
    白桦
    Betula platyphylla
    0.219.561.8295.3375
    樟子松
    Pinus sylvestris var. mongolica
    1.116.5491.6157.3141
    山杨
    Populus davidiana
    4.17.021.8234.059
    柳树
    Salix matsudana
    0.323.521.1123.7119
    柞树
    Quercus mongolica
    0.214.5220.535.03
    下载: 导出CSV

    表  3  空间结构参数计算公式及变量定义

    Table  3.   Calculation formula of spatial structure parameters and its significance

    空间结构参数
    Spatial structure parameter
    计算公式
    Formula
    变量定义
    Variable definition
    V-Hegyi指数
    V-Hegyi index
    $\scriptstyle {{\rm{CI}}_i = \sum\limits_{j = 1}^n {\frac{{d_j}}{{d_i L_{ij}}}} }$Lij为对象木i与竞争木j之间的距离;di为对象木i的胸径;dj为竞争木j的胸径;n为竞争木株数。Lij is the distance between the object tree i and the competition tree j; di is the DBH of the object tree i; dj is the DBH of the competition tree j; n is the number of competing trees
    V-混交度
    V-Mi
    $\scriptstyle {M_i = \frac{1}{n}\sum\limits_{j = 1}^n {v_{ij}} }$n为邻近木株数;当参照树i与相邻木j非同种时vij = 1;否则vij = 0。n is the number of adjacent trees; vij = 1 when the reference tree i is not the same as the adjacent tree j; otherwise vij = 0
    V-大小比
    V-Ui
    $\scriptstyle {U_i = \frac{1}{n}\sum\limits_{j = 1}^n {k_{ij}} }$n为邻近木株数;当参照树j的胸径小于中心木 i的胸径,kij = 1;否则kij = 0。n is the number of adjacent trees; when the DBH of the reference tree j is smaller than the DBH of the central tree i, kij = 1; otherwise kij = 0
    分布格局
    Spatial pattern
    SD = [1.264, 1.402]SD为Voronoi图多边形边数的标准差,当SD = [1.264, 1.402],林分呈随机分布;当SD < 1.264时,林分呈均匀分布;当SD > 1.402时,林分呈聚集分布。SD is the coefficient of variation of the number of polygons in the Voronoi diagram. When SD = [1.264, 1.402], the stands are randomly distributed; when SD < 1.264, the stands are evenly distributed; when SD > 1.402, the stands are aggregated distributed
    下载: 导出CSV

    表  5  各林型空间结构参数与补植幼树信息表

    Table  5.   Spatial structure parameters and replanting sapling information table for each forest type

    林分类型
    Forest type
    林分空间结构参数 Forest spatial structure index补植幼树 Replanting sapling
    V-Hegyi指数
    V-Heygi index
    V-混交度
    V-Mi
    V-大小比
    V-Ui
    分布格局
    Spatial pattern
    树种
    Species
    株数
    Tree number
    白桦纯林
    Betula platyphylla forest
    2.580.140.50随机
    Random
    兴安落叶松
    Larix gmelinii
    660
    落叶松白桦混交林
    Larix gmelinii and Betula platyphylla mixed forest
    3.130.410.50随机
    Random
    兴安落叶松
    Larix gmelinii
    1 970
    针叶混交林
    Larch coniferous mixed forest
    3.960.400.50聚集
    Aggregation
    兴安落叶松
    Larix gmelinii
    315
    下载: 导出CSV

    表  4  空间结构参数分级表

    Table  4.   Classification table of spatial structure parameters

    等级
    Grade
    V-Hegyi指数 V-Hegyi indexV-混交度 V-MiV-大小比 V-Ui
    取值区间
    Value range
    状态描述
    State description
    取值区间
    Value range
    状态描述
    State description
    取值区间
    Value range
    状态描述
    State description
    (0.00, 2.50]极弱度竞争
    Extremely weak competition
    0.00零度混交
    Zero mixture
    0.00优势
    Dominant
    (2.50, 5.00]弱度竞争
    Weak competition
    (0.00, 0.25]弱度混交
    Weak mixture
    (0.00, 0.25]亚优势
    Subdominant
    (5.00, 7.50]中度竞争
    Medium competition
    (0.25, 0.50]中度混交
    Medium mixture
    (0.25, 0.50]中庸
    Medium
    (7.50, 10.00]强度竞争
    Intensive competition
    (0.50, 0.75]强度混交
    Intensive mixture
    (0.50, 0.75]劣势
    Inferior
    (> 10.00)极强度竞争
    Extremely intensive competition
    (0.75, 1.00]极强度混交
    Extremely intensive mixture
    (0.75, 1.00]绝对劣势
    Absolute inferior
    下载: 导出CSV
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出版历程
  • 收稿日期:  2019-01-15
  • 修回日期:  2019-03-04
  • 网络出版日期:  2019-05-08
  • 刊出日期:  2019-05-01

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