云南陆良植烟土壤粒径分布及其分形维数空间变异研究

Spatial Variation of Soil Particle Distribution and Its Fractal Dimensions in a Tobacco Planting Area——A Case Study of Luliang Tobacco Growing Area

采用GPS定位技术,在陆良烟区采集土壤样品341个。采用经典统计学、地统计学和分形数学相结合的方法研究了土壤粒径分布及其分形特征的总体特征、空间变异特征,同时分析了土壤粒径分形维数与土壤颗粒组成及土壤养分的关系,以及土壤粒径及其分形维数的影响因素。结果表明,土壤颗粒含量及其分形维数在不同质地土壤间存在显著或极显著水平差异;粘粒含量和分形维数表现为轻粘土>重壤土>中壤土>轻壤土,砂粒和粉粒含量则相反;土壤颗粒质量分形维数在2.524~2.928之间,平均为2.823;土壤颗粒分形维数与土壤粘粒含量呈极显著正相关关系,与粉粒及砂粒含量呈极显著负相关关系;土壤颗粒分形维数可直观地反映土壤粒径分布;土壤颗粒含量和土壤粒径分形维数均具有中等的空间相关性,其空间变异是由结构性因素和随机性因素共同决定的结果,变程仅为0.12~0.27 km,表明其空间自相关范围较小,空间分布主要呈东西向变化趋势,高低值区域分异和明显;土壤粒径分形维数D值与全氮、全磷、全钾、碱解氮和速效钾呈极显著正相关,与有效磷含量呈极显著负相关,土壤分形维数可用于表征土壤养分状况;海拔高度、有机质、土壤类型、地形、轮作模式均对土壤颗粒含量和土壤粒径分形维数有显著影响。

Based on GPS technology,341 soil samples were collected from areas in Luliang County. Descriptive analysis characteristics,spatial distribution of soil particle and its fractal dimensions（ D value） were studied. Relationship between D value and soil particle distribution as well as the main nutrients were analyzed and special attention was paid to the influencing factors of soil particle content and D value. The results indicated that there were significant or very significant differences of soil particle content and D value between different soil textures： light clay heavy loam medium loam light loam. The opposite was observed with the content of sand and silt.Mean of D value was 2. 823 with an amplitude of 2. 524 - 2. 928. D value had a highly significant positive correlation with the weight percentage of clay soil（ 〈0. 002 mm）,and at the same time a highly significant negative correlation with the weight percentage of sandy soil（ 〉0. 05 mm） and silt（ 0. 002-0. 05 mm）. There was a moderate spatial correlation between soil particle content and D value. The spatial variability was determined by structural factors and random factors and the variable range was only 0. 12-0. 27 km. The spatial autocorrelation was of a narrow scope and the spatial distribution was mainly with an east-west trend with high and low values of regional differentiation. There was a highly significant positive correlation between D value and total N,as well as total K,total P,available N,and available K,while there was a highly significant negative correlation between D value and available P. Altitude,organic matter,soil types,terrain,and rotation pattern mode had significant effects on the soil particle content and soil particle size fractal dimension.