Multifunctional Woody Polycultures and their Influence on Soil Organic Carbon
This study investigates the impact of woody perennial polycultures (WPP) on soil organic carbon (SOC) change in previously row-cropped marginal lands. After seven years, changes in SOC were quantified across three polyculture treatments varying in species and density, against the corn-soybean control. Utilizing both grid and plot-based sampling, the research assessed relationships between labile organic matter fractions (Particulate Organic Matter (POM), Potentially Mineralizable Nitrogen (PMN)), and inherent and landscape factors, and SOC change. Findings revealed significant increases in SOC stocks across all treatments including the control, with gains ranging from 0.75 to 4.79 Mg C ha-1 yr-1. Gains in stocks (0-60cm) were larger in the lower than higher diversity WPP treatments. Gains in SOC increase with depth up until 30-45cm. Gains in POM-C and POM-N concentrations observed under polycultures were greatest in the surface depths. Topographic factors, Bray I P, MS, and PMN suggest how site factors influence SOC change at different depths.
