Digital mapping of soil salinity at various depths using an EM38
2019
Narjary, Bhaskar | Meena, Murli Dhar | Kumar, Satyen | Kamra, Sushil Kumar | Sharma, Dinesh Kumar | Triantafilis, John
PROBLEM DEFINITION: Spatial information on salinity is required at the farm level to enable suitable soil, crop and water management practices. RATIONALE: To facilitate this, we used an electromagnetic (EM) induction instrument for rapid measurement of apparent soil electrical conductivity (EC ₐ—mS m–¹) across the 11 ha area of the Central Soil Salinity Research Institute experimental farm in Nain, Haryana, India. METHODS: The ECₐ was measured using an EM38 in horizontal (ECₐₕ) and vertical (ECₐᵥ) modes on a grid survey. Using the ECₐ data, we selected 21 locations using the response surface sampling design (RSSD) module of Electrical Conductivity Sampling Assessment and Prediction (ESAP) software. We collected soil samples at four depth increments, including two topsoil (0–0.15 and 0.15–0.30 m), a subsurface (0.3–0.6m) and a subsoil (0.6–0.9m) and measured the soil electrical conductivity (EC ₑ—dS m–¹). RESULTS: We developed multiple linear regression to predict ECₑ using the ESAP software from ECₐₕ and ECₐᵥ and two trend surface parameters (i.e., Easting and Northing) across the farm. The prediction accuracy and bias were compared at different depth increments, and results of the spatial distributions of ECₑ using ordinary kriging (OK) interpolation were described in terms of the crop and soil use and management implications. CONCLUSIONS: We conclude the overall approach allows for generations of a digital soil maps (DSMs) of ECₑ which serve as baseline data that will allow the monitoring of any rehabilitation effort of salt‐affected soils according to their actual degree of salinity.
Mostrar más [+] Menos [-]Palabras clave de AGROVOC
Información bibliográfica
Este registro bibliográfico ha sido proporcionado por National Agricultural Library