Quantitative evaluation of soil salinity and its spatial distribution using electromagnetic induction method.

In the Lower Yellow River Delta, soil salinity is a problem due to the presence of a shallow, saline water table and marine sediments. Spatial information on soil salinity at the field level is increasingly needed, particularly for better soil management and crop allocation in this area. In this paper, a mobile electromagnetic induction (EMI) system including EM38 and EM31 is employed to perform field electromagnetic (EM) survey, and fast determination and quantitative evaluation of the spatial pattern of soil salinity is discussed using the field EM survey data. Optimal operation modes of EM38 and EM31 are determined to establish multiple linear regression models for estimating salinity from apparent soil electrical conductivity (ECa). Spatial trend and semivariogram are illustrated and spatial distribution of field salinity status is further visualized and quantitatified. The results suggest that ECa (EM38 and EM31) data is highly correlated with salinity, and that the interpretation precision of soil salinity at various layers can be improved using EM38h and EM31h (where h represents the horizontal mode of EM measurement). Both EM38h and EM31h exhibit significant geographic trend. Nested spherical models fit the semivariance of EM38h and EM31h better than single spherical models. Spatial autocorrelation of EM31h is stronger than that of EM38h, and short-range variation is the chief constitute of spatial heterogeneity for both EM38h and EM31h. Quantitative classification shows that soil salinity exhibits the trend of accumulation in the root zone. In 0-1.0Â m solum, heavy salinized and saline soils are the predominant soil types, accounting for 54% and 41% of total survey area, respectively. The area of light and moderate salinized soils is comparatively small, which accounts for only 0.4% and 4.6%, respectively.

[1]  M. Cannon,et al.  Use of the Electromagnetic-Induction Meter (EM38) as a Tool in Managing Salinisation , 1997 .

[2]  Timothy C. Coburn,et al.  Geostatistics for Natural Resources Evaluation , 2000, Technometrics.

[3]  F. D. Whisler,et al.  Spatial Variability Analysis of Soil Physical Properties of Alluvial Soils , 2005 .

[4]  Scott M. Lesch,et al.  Spatial Prediction of Soil Salinity Using Electromagnetic Induction Techniques: 1. Statistical Prediction Models: A Comparison of Multiple Linear Regression and Cokriging , 1995 .

[5]  J. D. Rhoades,et al.  Monitoring for temporal changes in soil salinity using electromagnetic induction techniques , 1998 .

[6]  John Triantafilis,et al.  Calibrating an Electromagnetic Induction Instrument to Measure Salinity in Soil under Irrigated Cotton , 2000 .

[7]  J. Triantafilis,et al.  Mapping clay content variation using electromagnetic induction techniques , 2005 .

[8]  Michael Edward Hohn,et al.  An Introduction to Applied Geostatistics: by Edward H. Isaaks and R. Mohan Srivastava, 1989, Oxford University Press, New York, 561 p., ISBN 0-19-505012-6, ISBN 0-19-505013-4 (paperback), $55.00 cloth, $35.00 paper (US) , 1991 .

[9]  Dennis L. Corwin,et al.  An Improved Technique for Determining Soil Electrical Conductivity-Depth Relations from Above-ground Electromagnetic Measurements1 , 1982 .

[10]  Peter J. Shouse,et al.  Determining soil salinity from soil electrical conductivity using different models and estimates , 1990 .

[11]  Kenneth A. Sudduth,et al.  Comparison of electromagnetic induction and direct sensing of soil electrical conductivity , 2003 .

[12]  Alex B. McBratney,et al.  Spatial dependence and classification of the soil along a transect in northeast Scotland , 1981 .

[13]  T. Miyamoto,et al.  Effects of Liquid-phase Electrical Conductivity, Water Content, and Surface Conductivity on Bulk Soil Electrical Conductivity1 , 1976 .

[14]  A. McBratney,et al.  Further results on prediction of soil properties from terrain attributes: heterotopic cokriging and regression-kriging , 1995 .

[15]  U. Schmidhalter,et al.  Calibration of electromagnetic induction measurements to survey the spatial variability of soils , 2001 .

[16]  Pierre Goovaerts,et al.  Geostatistical modelling of uncertainty in soil science , 2001 .

[17]  Liu Gao-huan,et al.  Saline-alkali land in the Yellow River Delta: amelioration zonation based on GIS , 2001 .

[18]  R. Aragüés,et al.  Soil salinity and its distribution determined by soil sampling and electromagnetic techniques , 2003 .

[19]  John Triantafilis,et al.  Five Geostatistical Models to Predict Soil Salinity from Electromagnetic Induction Data Across Irrigated Cotton , 2001 .

[20]  Mahmut Çetin,et al.  Spatial and temporal changes of soil salinity in a cotton field irrigated with low-quality water , 2003 .

[21]  Laurent Barbiero,et al.  Salt distribution in the Senegal middle valley Analysis of a saline structure on planned irrigation schemes from N'Galenka creek , 2001 .

[22]  G. C. Topp,et al.  Advances in Measurement of Soil Physical Properties: Bringing Theory into Practice , 1993 .

[23]  Dennis L. Corwin,et al.  Assessment of Non-Point Source Pollution in the Vadose Zone , 1999 .

[24]  Robert S. Freeland,et al.  Soil Investigations using Electromagnetic Induction and Ground-Penetrating Radar in Southwest Tennessee , 2002 .

[25]  A. Konopka,et al.  FIELD-SCALE VARIABILITY OF SOIL PROPERTIES IN CENTRAL IOWA SOILS , 1994 .

[26]  Peter G Slavich,et al.  Estimating average rootzone salinity from electromagnetic induction (EM-38) measurements. , 1990 .

[27]  Dennis L. Corwin,et al.  Measurement of Inverted Electrical Conductivity Profiles Using Electromagnetic Induction1 , 1984 .

[28]  Dennis L. Corwin,et al.  Characterizing soil spatial variability with apparent soil electrical conductivity , 2005 .

[29]  R. Yao,et al.  Calibration of Soil Electromagnetic Conductivity in Inverted Salinity Profiles with an Integration Method , 2007 .

[30]  J. D. Rhoades,et al.  Instrumental Field Methods of Salinity Appraisal , 2012 .

[31]  Dennis L. Corwin,et al.  Mapping Soil Salinity Using Calibrated Electromagnetic Measurements , 1992 .

[32]  David J. Strauss,et al.  Spatial Prediction of Soil Salinity Using Electromagnetic Induction Techniques: 2. An Efficient Spatial Sampling Algorithm Suitable for Multiple Linear Regression Model Identification and Estimation , 1995 .

[33]  Jacques Gallichand,et al.  Spatial interpolation of soil salinity and sodicity for a saline soil in Southern Alberta , 1992 .

[34]  Thomas E. Fenton,et al.  Influence of Soil Water Content, Clay, Temperature, and Carbonate Minerals on Electrical Conductivity Readings Taken with an EM‐38 , 2002 .

[35]  Peter G Slavich,et al.  Determining ECa-depth profiles from electromagnetic induction measurements. , 1990 .

[36]  Jan M. H. Hendrickx,et al.  Soil Salinity Assessment by Electromagnetic Induction of Irrigated Land , 1992 .

[37]  John Triantafilis,et al.  Application of a mobile electromagnetic sensing system (MESS) to assess cause and management of soil salinization in an irrigated cotton‐growing field , 2002 .

[38]  Marc Van Meirvenne,et al.  Soil salinity mapping using spatio-temporal kriging and Bayesian maximum entropy with interval soft data , 2005 .