Can biochar restore soil quality in a degraded forest and vineyard soil in a one-year percolation lysimeters study, in Portugal?

The use of biochar has increased worldwide in the last years due to its good results for several soil quality indicators. However, restoration potential depends on the type and amount of biochar for each specific soil and land use. In order to investigate this restoration potential differential, we conducted an experiment where we amended two contrasting degraded soils with the same biochar. We installed a controlled and fully randomized percolation lysimeter experiment (3 replicates) with 15 lysimeters on a moderately steep slope angle, monitored for one year. Two types of soil were collected, a low organic matter, hydrophilic vineyard soil and a high organic matter, hydrophobic forest soil. Biochar was applied at 4% for both soils, and an additional treatment at 2% for the forest soil only. Selected soil quality indicators are: soil organic matter, medium weight diameter, aggregate stability, bulk density, pH, electric conductivity, potassium (K), phosphorus (P), soil water repellency, biomass quality. The present study comprises four data collections in different seasons along the year, enabling to compare the development of the biochar effects on different types of soil and its short- and medium-term behaviour.