角尺度是一个描述林木空间分布格局的新参数,它通过描述邻近木围绕中心木的均匀性来判定林木分布格局,对空间结构具有很强的解析能力,其应用方兴未艾。为了制定基于Voronoi图计算角尺度时的相关标准,通过1 000次实验,模拟产生了1 000个随机分布面积为1hm2的大样地,确定了基于Voronoi图研究角尺度的标准角为360°/(n+1),通过拉依达准则确定了随机分布时角尺度均值的取值范围为[0.327,0.357],并结合角尺度的定义推理出,均匀分布时角尺度均值的取值范围为[0,0.327),团状分布时角尺度均值的取值范围为(0.357,1]。通过聚集指数和角尺度两种方法分别分析了福寿林场杉木生态公益林中6个实际调查样地的林木空间分布格局,结果是一致的。这一标准的提出为进一步完善角尺度理论,扩大其应用范围,起到了重要的推动作用。
The uniform angle index was a new parameter for describing the distribution pattern of tree positions.It described the degree of spatial regularity of the neighboring trees around a given reference tree.This parameter,accepted by more and more researchers,can be used to analyze complicated forest spatial structures.In order to put forward standards for uniform angle index,based on Voronoi diagram,in this paper,1000 randomly distributed plots with 1hm2 (100m×100m)each one,were simulated and analyzed.And the standard angle of the uniform angle index based on Voronoi diagram was formulated by 360°/(n+1).The critical value for the identification of tree random distribution pattern was discussed within the interval μ±3σ.The mean value of the uniform angle index for the random case was defined by the bounds[0.327,0.357].It can be inferred by the definition of the uniform angle index that a 公式 value of less than 0.327 was most likely from a regular distribution,values exceeding 0.357 were most likely from a clumped distribution.Finally,the tree spatial distribution pattern of six plots in Cunninghamia lanceolata non-commercial forest were analyzed by two different methods,i.e.aggregation index and uniform angle index,and they were same.This new judgment criterion to analyze the type of tree spatial distribution represented an important improvement of the uniform angle index theory.
[1]孔雷,杨华,亢新刚,等.林木空间分布格局研究方法综述[J].西北农林科技大学学报:自然科学版,2011,39(5):119-125.
[2]闫海冰,韩有志,杨秀清,等.华北山地典型天然次生林群落的树种空间分布格局及其关联性[J].生态学报,2010,30(9):2311-2321.
[3]惠刚盈,李丽,赵中华,等.林木空间分布格局分析方法[J].生态学报,2007,27(11):4717-4728.
[4]李明辉,何风华,刘云,等.林分空间格局的研究方法[J].生态科学,2003,22(1):077-081.
[5]Aguirre O,Hui G Y,Gadow K V,et al.An analysis of spatial forest structure using neighborhood-based variables[J].Forest Ecology and Management,2003,183:37-45.
[6] Hui G Y,Gadow K V.Das winkelmass-theoretische überlegungen zum optimalen standardwinkel [J].Allgemeine Forst und Jagdzeitunng,2002,173:173-177.
[7] Hui G Y,Albert M,Gadow K V.Das Umgebungsma? als parameter zur nachbildung von bestandesstrukturen[J].Forstw Cbl,1998,117:258-266.
[8]惠刚盈.基于相邻木关系的林分空间结构参数应用研究[J].北京林业大学学报,2013,35(4):1-8.
[9]惠刚盈.角尺度——一个描述林木个体分布格局的结构参数[J].林业科学,1999,35(1):37-42.
[10]惠刚盈,K.v.Gadow,胡艳波.林分空间结构参数角尺度的标准角选择[J].林业科学研究,2004,17(6):687-692.
[11]惠刚盈,K.v.Gadow,胡艳波,等.林木分布格局类型的角尺度均值分析方法[J].生态学报,2004,24(6):1225-1229.
[12]Pommerening A.Evaluating structural indices by reversing forest structural analysis[J].Forest Ecology and Management,2006,224:266-277.
[13]汤孟平,陈永刚,施拥军,等.基于Voronoi图的群落优势树种种内种间竞争[J].生态学报,2007,27(11):4707-4716.
[14]汪平,贾黎明,魏松坡,等.基于Voronoi图的侧柏游憩林空间结构分析[J].北京林业大学学报,2013,35(2):39-44.
[15]汪平.北京西山侧柏、油松游憩林抚育效果研究[D].北京:北京林业大学,2013:33-36.
[16]章雪莲.基于GIS的森林可视化与空间结构分析技术研究[D].杭州:浙江农林大学,2009:43-45.
[17]郝江勃.黄土高原柴松群落空间结构量化[D].西安:陕西师范大学,2011:28-50.
[18]武爱彬,游先祥,赵艳霞,等.应用3S获取与分析侧柏人工林空间结构研究[J].浙江农林大学学报,2014,31(1):57-63.
[19]郝月兰.基于林分空间结构优化的采伐木确定方法研究[D].北京:中国林业科学研究院,2012:40-42.
[20]郝月兰,张会儒,唐守正.Voronoi图方法确定云冷杉林最近邻木的适用性研究[J].林业资源管理,2011(6):59-64.
[21]赵春燕,李际平,李建军.基于Voronoi图和Delaunay三角网的林分空间结构量化分析[J].林业科学,2010,46(6):78-84.
[22]王芳.基于ArcGIS林分空间结构的研究——以武夷山保护区为例[D].南京:南京林业大学,2013:27-37.
[23]Gadow K V,Hui G Y,Albert M.Das Winkelmaβ -ein Strukturparameter zur Beschreibung der Individualverteilung in Waldbest?nden[J].Centralblatt für das Gesamte Forstwesen,1998,115:1-10.
[24]Hui G Y,Gadow K V,Das Winkelmaβ.Herleitung des optimalen Standardwinkels.[J].Allg.Forst- u.J.-Zeitung,2002,173:173-177.
[25]Pommerening A,Stoyan D.Edge-correction needs in estimating indices of spatial forest structure[J].Can.J.For.Res.,2006,36:1723-1739.
[26]Pommerening A.Evaluating structural indices by reversing forest structural analysis[J].Forest Ecology and Management,2006,224:266-277.
[27]惠刚盈,Klaus von Gadow,胡艳波,等.结构化森林经营[M].北京:中国林业出版社,2007.
[28]梁之舜,邓集贤.中山大学数学力学——概率论及数理统计[M].北京:高等教育出版社,1980.
[29]Mason W L,Connolly T,Pommerening A,et al.Spatial structure of semi-natural and plantation stands of Scots pine in northern Scotland [J].Forest,2007,80(5):567-586.
