Open AccessDiffused Reflectance Spectroscopy for Characterization of Salt-Affected Soil (SAS) Attributes
Author(s) -
Arijit Barman,
Rajeev Srivastava
Publication year - 2019
Publication title -
agropedology
Language(s) - English
Resource type - Journals
ISSN - 0971-1570
DOI - 10.47114/j.agroped.2019.jun2
Subject(s) - vnir , loam , soil salinity , salinity , soil science , soil water , topsoil , soil test , sodium adsorption ratio , environmental science , hyperspectral imaging , mineralogy , chemistry , geology , remote sensing , irrigation , agronomy , oceanography , drip irrigation , biology
Identification of soil salinity based on traditional methods (measurement in saturation extract) required time, labour and capital, whereas, ground based non-imaging hyperspectral remote sensing estimates the soil salinity and alkalinity parameters within limited resources and can be used for real time monitoring purpose. Laboratory experiment was conducted to study the spectral properties using VNIR spectroscopy in silt loam and silty clay loam soil saturated with different levels of chloride, sulphate and carbonate of sodium salts. Salinity absorption features were more pronounced around 1900 nm, followed by 1400 and 2200 nm. The salt concentration was inversely related to reflectance values in saline soils. Wavelength was shifted from 1900 nm to higher wavelength value and this shifting feature was also correlated with the increase in salt concentration. Relatively high correlation coefficients of ECe, saturated extract Na+ and Cl- with soil reflectance values were found in between 1420 to 2020 nm than other soil properties. Increased use and application of VNIR for salt-affected soil would help establish a detailed spectral library through captured signature in sodium salt saturated soil.