Physical properties of an Orthic Black Chernozem after 5 years of liquid and solid pig manure application to annual and perennial crops

Pig (Sus scrofa) manure is added to the soil to supply nutrients and improve soil properties. To our knowledge, no direct comparison has been made on the effect of liquid pig manure (LPM) and solid pig manure (SPM) on the physical properties of a prairie soil. This study was established in 2009 at the University of Manitoba's Ian Morrison Research Station in Carman, Manitoba. The treatment design was a split-plot structure with cropping system as the main plot and manure treatments as subplots. Five years after the study was initiated, soil samples were collected from the 0-10 cm and 10-20 cm depth intervals for determination of bulk density, saturated hydraulic conductivity (K-sat), and water retention at field capacity and permanent wilting point (PWP). For wet aggregate stability, samples were collected from the 0-5 cm layer. Land application of SPM significantly decreased bulk density by 14%, significantly increased K-sat by 110% in the 0-10 cm layer, and resulted in a 30% increase in wet aggregate stability (P < 0.05). In perennial plots, SPM increased water retention at field capacity, PWP, and available water in the 0-10 cm compared with annual plots. This was not the case for LPM-amended soils. We conclude that SPM has the potential as an organic amendment to improve the physical properties of the topsoil.