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种群的空间分布格局是由多种机制的交互作用而形成,是探究生物多样性维持机制的基础。北热带喀斯特季节性雨林是我国北热带石灰岩山地具有地带性特征的植被,其生境的典型特征在于土层浅薄、岩石裸露率高、贮水能力低和周期性水淹,以及富钙强碱性环境等。本研究基于广西弄岗北热带喀斯特季节性雨林15 ha动态监测样地的第一次调查资料,采用双关联g(r)函数点格局方法,分析了雨林中出现个体数≥15株的160个种的种群空间分布格局以及不同类群间种群分布的差异。研究表明:160种木本植物中有146种在0–10 m的尺度上呈聚集分布,且随着空间尺度的增大,聚集度呈下降趋势;物种的种群聚集度与其物种多度、平均胸径和最大胸径成负相关;常绿物种的种群聚集度与落叶物种间差异不显著;不同生活型间的种群聚集度差异显著,总体表现为亚乔木层物种高于乔木层,灌木层物种显著高于亚乔木层;剔除生境异质性后大部分物种表现为随机分布,仅少部分物种的种群表现为聚集分布。这表明物种的功能属性如物种多度、生活型等可较好地预测物种的分布格局。此外,物种种群的分布格局还受生境异质性的影响,且不同物种受生境异质性影响的程度不同。
The spatial distribution pattern of the population is formed by the interaction of various mechanisms and is the basis for exploring the mechanism for maintaining biodiversity. The northern tropical karst seasonal rainforest is a kind of vegetation with zonal characteristics in the northern tropical limestone mountains. Its habitat is characterized by shallow soil, high rock exposed rate, low water storage capacity, periodic flooding, and calcium-rich strong alkaline Environment and so on. Based on the first survey data of 15 ha dynamic monitoring plots of the tropical karst rainforest in the north of Nonggang, Guangxi, the paper analyzed the distribution of 160 The spatial distribution pattern of species and the distribution of populations among different species. The results showed that 146 of 160 species of woody plants were clustered on the scale of 0-10 m, and the degree of aggregation decreased with the increase of spatial scale. The degree of population aggregation, the species abundance, the mean The DBH and DBH were negatively correlated. The population aggregation of evergreen species was not significantly different from that of deciduous species. The population aggregation degree of different life forms was significantly different. The overall population of sub-arbor layer was higher than arbor layer and shrub layer was significant Higher than the arbor layer. Most of the species excluding the habitat heterogeneity showed random distribution, while only a few of the species showed aggregated distribution. This indicates that species functional properties such as species abundance, life-style and so can better predict species distribution patterns. In addition, the distribution patterns of species populations are also affected by habitat heterogeneity, and the extent to which different species are affected by habitat heterogeneity is different.