Organic carbon controls water retention and plant available water in cultivated soils from South Greenland

A groundbreaking study reveals that organic carbon (OC) plays a dominant role in controlling soil water retention and plant available water (PAW) in agricultural soils of South Greenland, with implications for high-latitude agriculture. The research found that a 1% increase in OC content can boost PAW by over 4%, nearly double the effect reported in recent meta-studies. This significant impact on soil-water balance was evident across various soil-water potentials, highlighting the critical role of OC in mitigating drought stress in warming climates. The study analyzed 464 soil samples from 20 fields using pedotransfer functions based on OC and clay content, providing a robust dataset that challenges conventional assumptions about soil water dynamics in circumpolar regions.

Weber, P. L., Blaesbjerg, N. H., Moldrup, P., Pesch, C., Hermansen, C., Greve, M. H., Arthur, E., & de Jonge, L. W. (2023). Organic carbon controls water retention and plant available water in cultivated soils from South Greenland. Soil Science Society of America Journal, 87(2), 203–215. Portico. https://doi.org/10.1002/saj2.20490