不同经营强度毛竹地下根茎的特征研究

The Rhizome Characteristics of Phyllostachys heterocycla cv. pubescens under Different Management Intensity

通过原位全挖法调查了3种不同强度毛竹林地下根茎特征,并运用分形理论和拓扑学对其分形特征进行了研究。结果发现:3种经营强度下毛竹地下根茎具有很好的分形特征,其分形维数值分别为Ⅰ类1.85±0.02、Ⅱ类1.89±0.002、Ⅲ类1.84±0.01,表现了毛竹根茎具有很强的空间拓展能力。3种经营强度下毛竹地下根茎的拓扑指数均接近1.0,表现为人字形分支结构,不同经营强度间无显著差异。相关性分析表明,分形维数和分形丰度的大小分别与根茎分枝角度、总长度、总体积和拓扑指数具有显著正相关,体现了这些参数是毛竹根茎在土壤中拓展能力的重要反映。

The rhizome system of Phyllostachys heterocycla cv.pubescens under different management patterns was excavated and measured in situ The fractal theory and topology analysis were used to research the rhizome characteristics,and the relationship between various rhizome parameters were explored by Pearson Correlation Analysis.The rhizome systems of Phyllostachys heterocycla cv.pubescens under three management patterns showed apparent fractal characteristics.The fractal dimension values were 1.85 ± 0.02,1.89 ± 0.002 and 1.84 ±0.01 under Pattern Ⅰ,Ⅱ and Ⅲ,respectively,which indicated that the rhizome system had a high ability to occupy the space in the soil.Topological index under different management patterns were all closely to 1.0,showing a herringbone rhizome-branching structure.The rhizome-branching structure were not significantly different between various management patterns.The rhizome total length,total volume,branch angle were all positively correlated to fractal dimension and fractal abundance,indicating that these parameters were important for the spatial occupation ability of the rhizomes.