Journal
JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING
Volume 132, Issue 5, Pages 436-444Publisher
ASCE-AMER SOC CIVIL ENGINEERS
DOI: 10.1061/(ASCE)0733-9437(2006)132:5(436)
Keywords
salinity; irrigation; electrical conductivity; soils
Ask authors/readers for more resources
Electromagnetic instruments are increasingly being used for in situ analysis and mapping of soil salinity in irrigated soils. This study develops calibration models for salinity assessment over regional scales on the order of tens of thousands of hectares. These models relate apparent soil electrical conductivity measured with the EM-38 electromagnetic induction meter (Geonics Ltd.) to traditional laboratory-measured saturated paste electrical conductivities (ECe). The study area is located in the Lower Arkansas River Valley, Colo. and is divided into two regions. At each of 414 randomly selected calibration sites, an EM-38 reading was taken and multiple soil samples were extracted for analysis. The sites chosen have soil ECe values ranging from I to 18 dS/m, gravimetric water contents (WC) from 0.02 to 0.4, and textures ranging from sands to clays. The best model for predicting soil ECe in both study regions is bivariate nonlinear and includes EM-38 vertical readings (EMV) and WC as covariates. Uncertainty in the calibration equations is addressed and tests are conducted at 48 independent sites. Results indicate that, while uncertainty is considerable in regional scale surveys, electromagnetic instruments can be calibrated for rapid reconnaissance of soil water salinity, providing reasonably accurate identification of salinization categories.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available