高寒草原不同退化阶段土壤颗粒分形特征  

Fractal Dimensions of Soil Particles in Different Degenerate Stages of Alpine Steppe

作　　者：柳妍妍[1] 胡玉昆[1] 公延明[1] 

机构地区：[1]中国科学院新疆生态与地理研究所中国科学院干旱区生物地理与生物资源重点实验室,新疆乌鲁木齐830011

出　　处：《水土保持通报》2013年第5期138-142,184,共6页Bulletin of Soil and Water Conservation

基　　金：国家重点基础研究发展计划"973"项目"干旱区地下有机碳过程及其与无机碳吸收的关系"(2009CB825103)

摘　　要：土壤分形维数能够很好地反映土壤结构及土壤养分特征。利用杨培岭的土壤分形模型对巴音布鲁克高寒草原4种不同退化阶段（未退化CK、轻度、中度和重度）土壤分形维数变化进行了研究，探讨了土壤分形维数与土壤颗粒含量、土壤理化性质及其与草地退化的关系。结果表明：（1）土壤分形维数随退化程度的加重其值增大，分形维数在2．573～2．635。（2）土壤分形维数与不同粒径土壤颗粒含量之间存在明显的相关关系，其中土壤分形维数与砂粒含量呈极显著负相关（P=0．01），与粉粒含量呈显著正相关（P〈O．05），与黏粒含量呈极显著正相关（p〈0．0001）。（3）土壤分形维数与有机质含量和全氮含量呈显著负相关，与容重呈显著正相关，与土壤退化指数呈负相关（但不显著）。（4）适度放牧有利于提升土壤质量，但不能超过阈值。Soil fractal dimension can better reflect soil texture and soil nutrient characters. Bayanbulak alpine grassland was taken as the research objective in August 2009. Yang Peiling＇s soil fractal model was used to analyze four different degenerate stages（nondegeneration CK and slightly, moderately and heavily deteriora ted grasslands）. Soil fractal dimension in relation to soil particles, soil physicochemical properties and soil degradation were discussed respectively. Results showed that. （1） Soil fractal dimension varied from 2. 573 to 2. 635 for the different degradations and increased with the increased degree of degradation. （2） There were significant differences between fractal dimension and different grain levels. Specifically, fractal dimen sion was significantly negatively correlated with sand content（p=0.01）, but significantly positively correla ted with clay content （p（0. 000 1）. （3） There existed significant negatively correlations between fractal dimension and SOM and total nitrogen content. The correlation between fractal dimension and soil bulk den sity was significantly positive. There was a positive correlation between fractal dimension and soil degrada tion index. （4） Moderate grazing could promote soil quality, but could not exceed the threshold value.

关 键 词：高寒草原 退化阶段 土壤颗粒 分形维数 

分 类 号：S812.2[农业科学—草业科学]