井冈山国家自然保护区典型常绿阔叶林林分空间结构分析

Stand spatial structure of typical evergreen broad-leaved forests in Jinggang Mountain National Nature Reserve

【目的】分析井冈山国家自然保护区典型常绿阔叶林的林分空间结构,为其恢复及次生林改造过程中的树种配置、人工抚育与综合定量评价林分空间结构等提供参考依据。【方法】于2010年6月在线路踏查的基础上,于井冈山国家自然保护区内具代表性的地段,分别对丝栗栲(Castanopsis fargesii)、罗浮栲(Castanopsis faberi)、红楠(Machilus thunbergii)3种典型常绿阔叶林群落设置标准地,每种群落类型各设置3块,对标准地进行调查,获取数据,计算群落的大小比数、混交度、角尺度和林分空间结构指数,对各群落的空间结构特征进行分析。【结果】丝栗栲、罗浮栲和红楠群落的平均大小比数分别为0.491,0.483和0.495,各群落平均处于中庸状态,林木大小分化程度不大;平均混交度分别为0.820,0.847和0.876,各群落中同一树种聚集在一起分布的情况较少;平均角尺度分别为0.535,0.519和0.531,林木分布格局均为聚集分布。经K-S检验,丝栗栲、罗浮栲和红楠群落间的大小比数、混交度和角尺度差异均不显著;平均林分空间结构指数分别为72.9,74.4和74.7,也表明了各群落的空间结构差异不明显。【结论】研究区3种典型群落总体上处于相对稳定的状态,形成亚热带常绿阔叶林多优势种的特征;林分空间结构指数将不同参数进行综合,与采用单一结构参数定量描述林分空间结构状态相比具有较好的效果,可为综合评价林分空间结构及制定合理经营措施等提供依据。

【Objective】This study analyzed the spatial structure of typical evergreen broad-leaved forests in Jinggang Mountain National Nature Reserve to provide reference for tree configuration,artificial tending and comprehensive quantitative assessment of spatial structure in restoration and secondary transformation of evergreen broad-leaved forests.【Method】Based on field survey in June 2010,three standard plots were set in each community at representative area of typical evergreen broad-leaved forests Castanopsis fargesii,Castanopsis faberi and Machilus thunbergii in Jinggang Mountain National Nature Reserve.Then,the spatial structures of the communities were analyzed using neighborhood comparison,mingling,angle index and forest spatial structure index.【Result】The mean neighborhood ratios of the three commu-nities were 0.491,0.483 and 0.495,indicating that the communities were in moderate state with small differentiation degrees.The mean mingling degrees were 0.820,0.847 and 0.876,indicating that same species were less aggregated distributed.The mean angle indexes were 0.535,0.519 and 0.531,showing that the distribution of the stands was aggregated.Different communities displayed no significant differences in the three space structure parameters based on K-Stest.The mean forest spatial structure indexes were 72.9,74.4and 74.7,showing that the differences in the spatial structure of the communities were not significant.【Conclusion】The three communities were in relatively stable state,showing the characteristics of subtropical evergreen broad-leaved forests with diverse and dominant species.Spatial structure index combined different parameters and was better in describing spatial structure of stands.This study provided theoretical basis for comprehensive evaluation of stand spatial structure and forest management.