不同坡长扰动土壤微团聚体及颗粒组成的分形特征  

Fractal features of soilmicro-aggregate and particle-size distribution under different slope length and disturbance surface

作　　者：郭晓朦 姚云[1,3] 何丙辉[1] 秦伟[4] GUO Xiaomeng YAO Yun HE Binghui QIN Wei(College of Resources and Environment, Southwest University/Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing 400715, China Sichuan AIIvery Environmental Protection Co.. Ltd, Chengdu 610000, China Water Authority of Xifeng County in Guiyang, Guizhou 551100, China Department of Sediment Research China Institute of Water Resources and Hydropower Research, Beijing 100038, China)

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]四川沃尔宜环保科技有限公司,成都610000 [3]贵州省贵阳市息烽县水务管理局,贵州551100 [4]中国水利水电科学研究院泥沙研究所,北京100038

出　　处：《中国农业大学学报》2017年第7期90-98,共9页Journal of China Agricultural University

基　　金：水利部公益性行业科研专项经费项目(201301048);国家自然科学基金(41271291)

摘　　要：为研究径流小区紫色土在不同坡长下人为扰动地表后土壤微团聚体及颗粒组成的分形特征,通过野外采样与室内分析相结合的方法,研究了在20、40和60m坡长下扰动地表与自然坡长下土壤微团聚体及颗粒组成的分形特征及其与土壤理化性质的关系。结果表明:土壤颗粒组成中的优势粒级是0.250~0.050 mm,含量在33.21%~22.55%。土壤微团聚体中的优势粒级是0.250~0.050mm,次级优势粒级是0.050~0.010mm。扰动地表下的土壤分形维数小于自然坡长下的分形维数,坡长越长分形维数越高。坡长越长土壤养分含量越高,即:60>40>20m,3种坡长扰动地表处理下的土壤养分均小于自然坡长下的土壤养分。土壤分形维数同土壤容重呈极显著正相关(P<0.01),同土壤全量养分呈极显著相关(P<0.01),扰动地表下的土壤分形维数同土壤孔隙度呈显著或极显著相关(P<0.01或P<0.05)。土壤微团聚体机及颗粒组成的分形维数能较好地反映紫色土区土壤的理化性状,更加直观的体现人为扰动地表后土壤理化性质及土壤性状的变化,为紫色土区土壤质量评价和农业评价提供科学依据。To provide a scientific basis for the rational development and utilization of land resources micro-aggregate and particle-size distribution under different slope lengths and disturbance surface were studied.Through field sampling and laboratory analysis,fractal features of rhizosphere soil micro-aggregate and particle-size and its relationship with soil physicochemical properties in the natural slope and disturbance surface in 20,40 and 60m were investigated.The results showed that：Soil particle-size distribution in the dominant aggregates was 0.250-0.050 mm,and the content was 33.21%-22.55%;Soil micro-aggregates in the dominant aggregateswere 0.250-0.050 mm and secondary advantage was 0.050-0.010mm;The fractal dimension under disturbance surface was less than the fractal dimension under natural slope length.The length of slope was longer and the fractal dimension was higher;Soil nutrient content ofthe longer slope length was higher in the order of 60〉40〉20m;Soil nutrients under disturbance surface were less than those under natural slope length in three slope lengths;Positive correlation between soil fractal dimension with the soil bulk density was significant（P〈0.01）while soil total nutrient was significantly associated（P〈0.01）and the dimension of soil fractal under disturbance surface with soil porosity were significant or very significantly correlated（P〈0.01 or P〈0.05）.In conclusion,the fractal dimension of soil micro-aggregate and particle-size distribution better reflected physical and chemical structure of soil in the purple soil area and more intuitively reflected the changing of soil structure and physical and chemical properties after the disturbance,which providing a scientific basis for soil quality evaluation and agricultural assessment in purple soil area.

关 键 词：坡长 扰动地表 土壤微团聚体 土壤理化性质 分形维数 

分 类 号：S152.32[农业科学—土壤学]