华北冲积平原壤质潮土的土壤粒径分形空间尺度分析

土壤在一定空间尺度范围内具备分形特征已经为大多数研究所认同,然而这种空间自相似性的存在区间却容易被忽视。该文利用激光衍射法测定了华北冲积平原黄河沿岸43组壤质潮土的土壤粒径分布数据(共93个粒级),并以此为基础分析了该类土壤颗粒分形特征的存在区间及其影响因素。结果表明,该类土壤大多只是在中小粒径级别均呈现严格的分形特征,在较粗砂粒尺度上不存在空间自相似性。分形特征存在区间会随黏粒含量增加呈现变小的趋势,而级配良好的土壤的自相似性空间范围也相对较宽。土壤颗粒的分形维数会受到土壤级配的不均匀系数、部分粒径较小颗粒的含量(〈50pm但不包含5~20pm的颗粒)和有效粒径等的明显影响;但该分形维数与土...

Full description

Saved in:
Bibliographic Details
Published in农业工程学报 Vol. 30; no. 4; pp. 118 - 124
Main Author 李晓鹏 刘建立 张佳宝 王伟鹏 辛文文
Format Journal Article
LanguageChinese
Published 中国科学院大学,北京 100049 2014
中国科学院南京土壤研究所土壤物理与盐渍土研究室,南京,210008%中国科学院南京土壤研究所封丘农业生态试验站,南京,210008%中国科学院南京土壤研究所土壤物理与盐渍土研究室,南京 210008
Subjects
Online AccessGet full text
ISSN1002-6819
DOI10.3969/j.issn.1002-6819.2014.04.015

Cover

More Information
Summary:土壤在一定空间尺度范围内具备分形特征已经为大多数研究所认同,然而这种空间自相似性的存在区间却容易被忽视。该文利用激光衍射法测定了华北冲积平原黄河沿岸43组壤质潮土的土壤粒径分布数据(共93个粒级),并以此为基础分析了该类土壤颗粒分形特征的存在区间及其影响因素。结果表明,该类土壤大多只是在中小粒径级别均呈现严格的分形特征,在较粗砂粒尺度上不存在空间自相似性。分形特征存在区间会随黏粒含量增加呈现变小的趋势,而级配良好的土壤的自相似性空间范围也相对较宽。土壤颗粒的分形维数会受到土壤级配的不均匀系数、部分粒径较小颗粒的含量(〈50pm但不包含5~20pm的颗粒)和有效粒径等的明显影响;但该分形维数与土壤容重和饱和导水率的关系却并不明显,这可能与该土壤在与结构和水力学性质关系密切的大颗粒尺度上并不具备分形特征有关。因此,研究土壤颗粒分形与土壤结构和水力学性质的关系时,应特别注意分形特征存在的空间尺度。
Bibliography:11-2047/S
soils; fractal dimension; particle size analysis; Chao soil; fractal magnitude; laser diffraction particle size analysis
It is widely accepted that soils have fractal characteristics in certain spatial scales. However, the exact magnitude of this spatial self-similarity is often neglected when doing fractal related researches. In this study, 43 sets of soil particle size distribution data of the Chao soil in North China Alluvial Plain were collected, and their particle size distributions with 93 levels were determined by laser diffraction analysis method (Beckman Coulter LS 13-320).The spatial magnitude orders of soils can be taken as fractal objectives and their affecting factors were analyzed based on the particle size distribution data. For determining the fractal magnitude of the soils, we used a typical scale method: 1) calculate the differential fractal dimensions in all the 93 particle size levels (Di, i=l, 2 93) according to the definition fractal; 2) choose a typical scale which is supposed t
ISSN:1002-6819
DOI:10.3969/j.issn.1002-6819.2014.04.015