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).