【摘要】 土壤水力特性与物理性质的空间异质性及其之间的关系在不同尺度上会有不同表现。采用消除趋势波动分析法对土壤水力特性(田间持水量、萎蔫系数和饱和导水率)和物理性质(机械组成、容重和有机碳含量)进行尺度分析。结果表明,只有在一定尺度范围内才能进行土壤水力特性空间变异分析和尺度转换(外推)。过小的尺度范围内不能摆脱空间相关的束缚,尺度太大时不能抓住主要控制因子,因此无法进行尺度外推。所研究砂壤质褐土田间持水量、饱和导水率、容重和有机碳含量可外推尺度范围较大,分别为55~155、50~125、50~125和50~135 m;砂粒、粉粒和黏粒含量的可外推尺度范围较小,为50~85 m,因此在进行空间尺度转换前应先确定其尺度外推范围。更多还原

【Abstract】 Spatial heterogeneities of soil hydraulic characteristics and soil physical properties,and their relationship may be different at different scales.Scaling analysis of soil hydraulic characteristics(field capacity,wilting point and saturated hydraulic conductivity) and physical properties(particle size distributions,bulk density and organic carbon content) was carried out using the Detrended Fluctuation Analysis(DFA) method.Results show that spatial variability analysis and scaling transformation(e.g.up-scaling) could be performed only within a certain range of scales.The fluctuation pattern cannot be up-scaled when the scale is too small,because it can not get free from spatial interdependency and hence reflects local scale features only.But when the scale is too large scale,it is hard to define dominant factors,including those with certain characteristic length scale.For the sandy loam cinnamon soil in the study,the ranges of up-scaling for field capacity,hydraulic conductivity,bulk density and organic carbon content are relatively large,being 55~155,50~125,50~125,and 50~135 m,respectively,but small for sand,silt and clay contents,being 50~85 m,indicating that it is essential to determine the range of up-scaling before spatial scaling transformation is performed.更多还原