The effect of arable management practices on carbon storage and fractions
Article: Assessing the effect of arable management practices on carbon storage and fractions after 24 years in boreal conditions of Finland
Authors: Salonen, Anna-Reetta et al.
Publication: Geoderma Regional
Soil organic matter (SOM) plays an important role in soil functions that are crucial for sustainable agriculture. Understanding how agricultural management and soil properties affect SOM in different soil depths would aid in maintaining and increasing SOM throughout the soil profile.
The study sampled a 24 year-old cultivation field experiment with organic and conventional cropping systems, and an adjacent unmanaged meadow to 70 cm soil depth. The samples were analyzed to assess the total organic carbon (OC) stocks and the distribution of OC into several different types of organic matter.
Over 83% of the soil OC was in the mineral-associated fraction. The distribution of OC across the different types was not strongly affected by soil management. Largest OC stocks together with the largest plant root biomass was found in the unmanaged meadow, which highlights the potential of deep-rooting plants in sequestering OC into the soil.
The results also indicate that aluminum and iron oxides can play an important role in transporting and stabilizing of OC in the soil profile.