贵州特有植物红花瘤果茶种群空间格局及数量动态研究

红花瘤果茶(Camellia rubituberculata)为地理分布狭窄的贵州特有植物,颇具经济价值。为查清其分布特征和评估其濒危状况,该文在红花瘤果茶的集中分布区设置三个典型样地进行调查,采用空间点格局及多元点格局分析法分析种群空间分布格局,利用种群动态量化指数分析预测种群数量动态规律。结果表明:(1)兴仁县新寨村大皮坡1号样地幼龄树的小尺度呈集群分布、大尺度呈随机分布,中龄树和老龄树均呈随机分布; 兴仁县新寨村槽子土2号样地的幼龄树均呈集群分布,中龄树和老龄树均呈随机分布; 晴隆县紫马乡龙头村上捧碧林区3号样地幼龄树、中龄树和老龄树均呈随机分布。(2)不同发育阶段的空间关联主要表现为1号样地幼龄树和中龄树均为负相关,幼龄树和老龄树在中小尺度上为负相关,在大尺度上为无相关,中龄树和老龄树均为无相关。2号样地幼龄树和中龄树在小尺度上为负相关,中大尺度上为无相关; 幼龄树和老龄树在中小尺度上为负相关,中大尺度上为无相关; 中龄树和老龄树均为无相关。3号样地的幼龄树和中龄树均为正相关; 幼龄树与老龄树在小尺度上为负相关,中尺度上为无相关,大尺度上为正相关; 中龄树和老龄树均为无相关。(3)种群数量动态分析表明3个样地中幼苗补充充裕,种群结构为增长型,但易受外界环境干扰、生态脆弱。(4)红花瘤果茶的生境异质性及其种内种间关系相互作用的结果是影响种群数量扩大和物种散布的主要因素。

Spatial distribution pattern and quantitative dynamics of the endemic plant Camellia rubituberculata in Guizhou Province

Camellia rubituberculata is endemic to Guizhou Province with narrow geographical distribution and has economic value. In order to find out its distribution characteristics and evaluate its endangered status, three typical sample plots were set up in concentrated areas, and the spatial distribution pattern of population was analyzed by spatial dot pattern and multivariate point pattern analysis, the quantitative index analysis of population dynamics was used to predict the dynamic law of population quantity. The results were as follows:(1)The young trees in Dapipo sample plot 1 showed cluster distribution in small-scale and random distribution in large-scale, and the distribution of middle-aged trees and old-aged trees in all scales were random. The young trees in Caozitu sample plot 2 were clustered at all scales, the middle-aged trees and the old-aged trees were random. The young trees, middle-aged trees and old-aged trees were randomly distributed in Shangpengbi sample plot 3.(2)The spatial correlations of different developmental stages mainly manifested that the young and middle-aged trees in sample plot 1 were negatively correlated at all scales, the young trees and old-aged trees were negatively correlated at medium and small scale, and there were no correlation in the large scale. The middle age trees and the old-aged trees were not related at all scales. In sample plot 2, there was negative correlation between young trees and middle-aged trees at small scale and no correlation at medium and large scales, young trees and old-aged trees were negatively correlated at medium and small scales, but not at the medium and large scales, there was no correlation between middle-aged trees and old-aged trees at all scales. The young trees and middle-aged trees in sample plot 3 were positively correlated at all scales; there was a negative correlation between young trees and old-aged trees on the small scale, but no correlation on medium scale, and positive correlation on the large scale; the middle-aged trees and old-aged trees were irrelevant at all scales.(3)The population quantitative dynamic analysis indicated that the seedlings in the three sample plots were well supplemented, and the population structure was growth type, but they were vulnerable to environmental disturbance and ecological fragility.(4)The results of habitat heterogeneity and interspecific interaction of C. rubituberculata are the main factors affecting population expansion and species dispersal.