广元市不同土地利用类型土壤的分形特征  

Fractal Characteristics of Soil under Different Land Utilization Type in Guangyuan

作　　者：李进峰[1] 宫渊波[1] 陈林武[2] 程永珍[1] 张发会[2] 

机构地区：[1]四川农业大学四川省生态林业工程省级重点实验室,四川雅安625014 [2]四川林业科学研究院,四川成都610081

出　　处：《水土保持学报》2007年第5期167-170,182,共5页Journal of Soil and Water Conservation

基　　金：国家"十五"重点科技攻关计划"四川盆周低山区水土流失综合治理技术与示范"子课题(2001BA606A-06-3);四川省重点学科森林培育学建设项目

摘　　要：以8个植被类型、2个农地和2个退耕地的土壤颗粒组成数据为基础，运用分形模型计算这12个土地利用类型土壤颗粒的分形维数，研究了土壤颗粒分形维数与土壤性状的关系。结果表明：（1）12个土地利用类型表层土壤颗粒的分形维数介于2．8185～2．9249之间。与退耕地和玉米地相比，各林地土壤颗粒分形维数小；与1990年的2．8633相比，2006年土壤颗粒分形维数（2．8592）减小；各团聚体分形维数规律不明显。（2）决定土壤颗粒分形维数大小的首先是〈o．002mm的含量，其次是0．05～0．25mm和0．0020．02mm的含量；决定团聚体分形维数大小的粒级含量由大到小的顺序是：2～5mm，0．5～1mm和1～2mm，其余粒级含量对分形维数影响较小。（3）土壤颗粒分形维数与团聚体分形维数可作为侵蚀指标，前者与土壤可蚀性因子相关关系显著，后者也可作为渗透蓄水指标。（4）在坡耕地基础上的退耕地比生态退化后的营林地具有更有利于水土保持的土壤分形特征。Take the soil granulometric composition data of 8 vegetation types, 2 farmlands and 2 rehabilitated land as the foundation, the utilization fractal model are considered as 12 land utilization type soil particles fractal dimension, and this paper studied the relationship between fractal dimension and the soil properties. The result showed that, 12 land utilization type surface layer soil particles fractal dimension is between 2. 818 5～2. 924 9. Every forest soil particles fractal dimension is small comparing with rehabilitated land and the corn field; Compared with the 2. 863 3 in 1990, soil fractal dimension 2. 859 2 is diminished in 2006. The law of granular fractal dimension is not obvious. Deciding the primo of soil particles fractal dimension is 〈0. 002 mm contents, the contents of 0.05 ～0.25 mm and 0. 002～0. 02 mm is second. The order deciding granular fractal dimension： 2～5 mm,0. 5～1 mm and 1～2 mm. The particles fractal dimension and the granular fractal dimension may accomplish the index of soil erosion, the latter may store water as penetration more index. Rehabilitated land has more beneficial to soil fractal characteristic about water and soil conservation than forestation in degraded land.

关 键 词：土地利用类型 颗粒分形维数 团聚体分形维数 土壤性状 

分 类 号：S152.3[农业科学—土壤学]