Soil hydrology and EMI
Conversion of boreal forest into agricultural land is likely to occur due to the shift of climatic zones and increasing food demand. However, any land conversion will affect the water balance and hence solute fluxes within the soil column and connected ecosystems. Understanding the consequences of land conversion on soil hydrology is essential to support an economically viable agriculture while minimizing its environmental footprint.
Hydrological simulations revealed lower saturation and higher infiltration rates for unconverted soils, indicating lower runoff and increased infiltration and deep percolation.
In contrast, agricultural soils have slower infiltration rates, particularly in the upper horizon.
Over the long term, agricultural conversion consequently increases erosion risk and nutrient loss by runoff.
This might further progressively limit groundwater recharge, affect hydrological processes and functions and future drought/flood conditions at catchment levels.
Electromagnetic induction (EMI)
EMI is a non-invasive geophysical method to map near subsurface features in engineering and environmental science. The working principle of EMI based on a two-coil system, that generates a primary magnetic field and induces eddy currents in the soil and creates a secondary magnetic field. The ratio between the two magnetic fields can be related to the electric conductivity (EC) of the subsurface. As EMI recorded integral EC values over a certain depth, its unit called apparent EC (ECa). The ease of use and the wide range of possible applications have made the use of EMI very attractive (example here).
Projects
Initial assessment of a new research farm: Pye Farm, Labrador
Labrador (the mainland portion of the province of Newfoundland and Labrador) is a sparsely populated but actively growing region of Canada. Like Yukon and northern Ontario, Labrador offers a snapshot…
Articles
Depth Sensitivity of Apparent Magnetic Susceptibility Measurements using Multi-coil and Multi-frequency Electromagnetic Induction
K. Sadatcharam, D. Altdorff, A. Unc, M. Krishnapillai and L. Galagedara, Journal of Environmental and Engineering Geophysics, 2020 Vol. 25 Issue 3 Pages 301-314 https://doi.org/10.32389/JEEG20-001 Apparent magnetic susceptibility (MSa) as recorded by electromagnetic induction (EMI) instruments could offer relevant information…
Comparison of Multi-Frequency and Multi-Coil Electromagnetic Induction (EMI) for Mapping Properties in Shallow Podsolic Soils
D. Altdorff, K. Sadatcharam, A. Unc, M. Krishnapillai and L. Galagedara Sensors 2020 Vol. 20 Issue 8 DOI: 10.3390/s20082330 Electromagnetic induction (EMI) technique is an established method to measure the apparent electrical conductivity (ECa) of soil as a proxy for…
Effect of Biochar Application Rates on the Hydraulic Properties of an Agricultural-Use Boreal Podzol
D. Altdorff, L. Galagedara, J. Abedin and A. Unc, Soil Systems 2019 Vol. 3 Issue 3, https://doi.org/10.3390/soilsystems3030053 Boreal agriculture struggles with soils of lower agronomic value, most of which are sandy with a low water holding capacity (WHC) and prone…
Temporal stability of soil apparent electrical conductivity (ECa) in managed podzols
E. Badewa, A. Unc, M. Cheema and L. Galagedara, Acta Geophysica 2019 Vol. 67 Issue 4 Pages 1107-1118, https://doi.org/10.1007/s11600-019-00306-1 The spatial variability in soil physical and hydraulic properties for a managed podzol was assessed using soil apparent electrical conductivity (ECa).…
Soil Moisture Mapping Using Multi-Frequency and Multi-Coil Electromagnetic Induction Sensors on Managed Podzols
E. Badewa, A. Unc, M. Cheema, V. Kavanagh and L. Galagedara, Agronomy 2018 Vol. 8 Issue 10, https://doi.org/10.3390/agronomy8100224 Precision agriculture (PA) involves the management of agricultural fields including spatial information of soil properties derived from apparent electrical conductivity (ECa) measurements.…
Effect of agronomic treatments on the accuracy of soil moisture mapping by electromagnetic induction
D. Altdorff, L. Galagedara, M. Nadeem, M. Cheema and A. Unc, CATENA 2018 Vol. 164 Pages 96-106, https://doi.org/10.1016/j.catena.2017.12.036 Electromagnetic induction (EMI) is an established method for mapping field-scale soil water content (SWC). However, the correlation between the recorded apparent electrical…
Impact of projected land conversion on water balance of boreal soils in western Newfoundland
D. Altdorff, L. Galagedara and A. Unc, Journal of Water and Climate Change 2017 Vol. 8 Issue 4 Pages 613-626, https://doi.org/10.2166/wcc.2017.016 Conversion of boreal forest into agricultural land is likely to occur due to the shift of climatic zones and…