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红树植物木榄种群植冠层结构的分形特征   总被引:9,自引:0,他引:9  
应用分形理论分析了山口国家级红树林保护区木榄种群植冠层结构的分形特征。木缆3a生枝条的计盒维数介于1.22-1.55之间,这些维数值揭示了分枝结构的复杂程度以及占据生态空间和利用生态空间的能力。分形维数为了解木缆的光能利用效率和掌握它的生长发育过程提供了一个有用的指标。根据双表面积法,20-50a的木缆树冠格局的分形维数介于2.21-2.54之间,表明叶片对树冠的填充程度较低,该树种具有阳生的性质。随着种群个体年龄的增长,树冠被叶片填充的程度出现了由高到低的变化,其分形维数相应地呈现由高到低的动态变化特征。根据植冠层的灰度图分析,得出种群植冠层的计盒维数介于1.47-1.61之间。计盒维数越大,表明种群植冠层的空间结构越松散,透光的空斑块越多,计盒维数有效地揭示了种群植冠层包含于图像中的结构信息及其复杂性。  相似文献   
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广西英罗港红树林区木榄群落土壤粒径分布的分形特征   总被引:12,自引:0,他引:12  
应用分形理论分析了广西英罗港红树林区小榄Bruguiera gymnorrhiza群落土壤粒径分布的分形特征。基于土壤粒径-重量分布资料计算,土壤粒径分布分形维数介于2.78-2.90之间。分形维数的大小与土壤中的细粘粒、盐分和有机质的含量呈显著正相关,与砂粒的含量呈显著负相关。不同质地的土壤,其粒径分布的分形维数呈现砂壤<轻粘土<中粘土的变化。土壤的质地类型、含盐量、有机质含量等是决定土壤粒径分布分形维数的主要因子。  相似文献   
3.
Annotation on Mangrove Plants   总被引:1,自引:0,他引:1  
This paper reviews and discusses the technical terms and definition of mangrove and lnangal, as well as mangrove plant. The word mangrove has been used to refer either to the constituent plant of tropical and subtropical intertidal community or to the community itself but this usage makes mote confusion. Being leaved mangrove in the more limited sense for the constituent plant species, mangal was proposed by MacNae (1968) as a term for mangrove community, which has been universally applied to most previous studies and should be adopted now. Mangrove should be therefore defined as a tropical and subtropical tree restricted to intertidal zones, which possesses some morphological specializion and physiological mechanism adapted to its habitat, and mangal as a tropical and subtropical forest community restricted to marine intertidal zones and periodically inundeated by the tides, A new term “consortive plant” is proposed here for herb. liana, epiphyte or parasite, which is restricted in the strict mangrove habitat.  相似文献   
4.
Wetland ecosystem in the Shenzhen Bay is one of the internationally important ecosystems in South China Region. Its core, with the Mai Po Mangrove Nature Reserve in Hong Kong on the one side and the Futian Mangrove Nature Reserve in Shenzhen on the other side, provides habitats for many rare and endangered wild birds, especially for migratory birds[1, 2]. With the economic development in Hong Kong and Shenzhen, a large mount of silt and untreated waste water are poured into the Shenzhe…  相似文献   
5.
The distribution patterns of mangrove Bruguiera gvmnorrhiza populations in southern China are analyzed using the box-counting method of fractal theory.The patterns of B.gymnorrhiza populations could be thought of as fractals as they exhibit self-similarity within the range of seale considered.Their fractal dimensions are not integer but fractional.ranging from 1.04 to 1.51.The unoccupied dimensions change from 0.49 to 0.96.The combined conditions of population density.pattern type and aggregation intensity together influence the values of fractal dimensions of patterns.The box counting is a useful and efficient method to investigate the complexity of patterns.Fractal dimension may be a most desirable and appropriate index for quantifying the horizontal spatial microstructure and fractal behaviors of patterns over a certain range of scales.  相似文献   
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