Hydraulic energy indices reveal spatial dependence in a subtropical soil under maize crop in Southern Brazil  

作　　者：Maria Eliza TUREK Robson Andre ARMINDO Ole WENDROTH 

机构地区：[1]Graduate Program of Environmental Engineering(PPGEA),Federal University of Paraná(UFPR),Curitiba 81531980(Brazil) [2]Department of Physics(DFI),Federal University of Lavras(UFLA),Mailbox 3037,Lavras 37200900(Brazil) [3]Department of Plant&Soil Sciences,University of Kentucky(UK),Lexington 40546-0091(USA)

出　　处：《Pedosphere》2021年第5期771-782,共12页土壤圈（英文版）

基　　金：financed in part by the Coordination of Improvement of Higher Education Personnel(CAPES),Brazil(No.001)。

摘　　要：Soil physical quality(SPQ)assessment is an important part in the evaluation of soil use,management,and conservation.It can be assessed using several physical properties,hydraulic indices,and functions.Soils from tropical and temperate regions represent different physical behaviors,and the quantification of their physical properties is important to support soil evaluation and modelling.The objective of this study was to evaluate the SPQ in a subtropical field under maize crop cultivation according to its physical properties,hydraulic indices,and functions in an attempt to infer the spatial variability and to determine the behavior of soil physical structure across a spatial domain.Commonly used soil key physical variables,such as texture,bulk density,total porosity,saturated hydraulic conductivity,and organic carbon content,were measured in a regular grid with a soil sampling density of 30 points per hectare,covering an area of0.5 ha.Saturated hydraulic conductivity varied strongly between subsamples and in the field,suggesting the heterogeneity of the soil structure regarding water drainage.The physical variables were combined with other indicators,which were based on the soil water retention curve and the pore size distribution(PSD)function.Correlation analysis was performed to verify the relationship between the measured and calculated variables,and some strong linear correlations were revealed,such as between aeration energy index and microporosity(r=0.608)and water retention energy index with microporosity(r=0.532)and with bulk density(r=0.541).For most sampled locations,the shape and location parameters of PSD showed results outside of the optimum ranges,whereas the hydraulic energy indices and cumulative hydraulic energy functions presented values that were similar to those found for some tropical soils described in the literature.The spatial variability of these indices was described using semivariograms and kriged maps,indicating the variability of the SPQ in this field.

关 键 词：GEOSTATISTICS integral energy pore size distribution soil physical indicators soil physical quality soil water retention curve 

分 类 号：S513[农业科学—作物学] S152