三峡库区4种不同草本植物根际土壤的颗粒分形特征  

Fractal Characteristics of Rhizosphere Soil Under Four Different Herbaceous Plants in the Three Gorges Reservoir Area

作　　者：陶俊[1] 何丙辉[1] 李天阳[1] 谌芸[1] 徐小军[1] 孙文艳[2] 

机构地区：[1]西南大学资源环境学院三峡库区生态环境教育部重点实验室,重庆400715 [2]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《水土保持学报》2013年第6期35-40,共6页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(40971166);国家科技支撑计划项目(2011BAD31B03)

摘　　要：研究了三峡库区4种不同草本植物根际土壤颗粒分形维数的空间变化特征以及分形维数与土壤性状的关系。结果表明：不同草本植物根际土壤粒径分布具有不同的分形特征，其分形维数的范围在2．6786～2．6939之间，大小顺序为：T2（百喜草）〉T4（香根草）〉T1（紫花苜蓿）〉T。（狗牙根）〉T5（对照）；不同草本在相同土层的全N含量、有机质含量、土壤容重、土壤pH值规律类似；不同草本植物根际土壤的分形维数与0．5～0．25，0．25～O．1，0．1～0．05mm粒径含量呈极显著负相关，与0．005～0．002，〈0．002mm粒径含量呈极显著正相关，土壤的颗粒越小，分形维数越大；分形维数与土壤有机质、容重、pH值和全N含量等没有显著的线性关系。土壤颗粒分形维数可用作评价三峡库区不同草本植物根际土壤肥力大小的定量指标。The fractal dimension of soil particle-size of rhizosphere under four different herbaceous plants and the relationship between fractal dimension and soil properties were studied in Three Gorges Reservoir area. The results showed that. The particle-size distribution of rhizosphere under different herbaceous plants had different fractal characteristics, the range of fractal dimensions were from 2. 678 6 to 2. 693 9, and following as 〉 T2 （Paspalum natatum ） 〉 T4 （Vetiveria zizanioides ） 〉 T1 （Medicago sativa ） 〉 T3 （ Cynodon dactylon ）〉 T5 （Control）. There were similar laws among the total nitrogen content, soil organic matter, soil bulk density and the pH values in the rhizosphere soil of different herbaceous plants. The fractal dimensions of rhizosphere soil under different herbaceous plants had extremely significant negative correlation with the particle-size of 0.5~0.25, 0.25~0.1, 0.1~0.05 mm, and had a very significant positive correlation with 0. 005~0. 002,~ 0. 002 mm. The smaller the soil particle size was,the greater the fractal dimension was. The fractal dimension had no significant linear relationship with soil organic matter, soil bulk density, pH and soil total N. Fraetal dimension of soil particle-size might be used as a quantitative index to evaluate the soil fertilizer of rhizo- sphere under different herbaceous plants in the Three Gorges Reservoir area.

关 键 词：根际土壤 土壤颗粒 分形维数 草本植物 

分 类 号：S152.3[农业科学—土壤学]