Biochar amendment to coarse sandy subsoil improves root growth and increases water retention

• DOI: 10.1111/sum.12102
• Publication Date: 2014-02-07T18:43:15Z
• Authors: E. W. Bruun; C. T. Petersen; E. Hansen; J. K. Holm; H. Hauggaard‐Nielsen
• Keywords: Subsoil; Amendment; Permanent wilting point; Topsoil

Abstract Crop yields and yield potentials on D anish coarse sandy soils are strongly limited due to restricted root growth poor water nutrient retention. We investigated if biochar amendment subsoil can improve development in barley significantly increase soil S pring ( H ordeum vulgare cv. Anakin) was grown columns (diameter: 30 cm) prepared with 25 cm topsoil, 75 biochar‐amended subsoil, un‐amended lowermost placed an impervious surface. Low‐temperature gasification straw‐biochar (at 0, 0.50, 1.0, 2.0, 4.0 wt%) slow pyrolysis hardwood‐biochar 2 were investigated. One wt% be scaled up 10 Mg/ha of char. After full irrigation drainage, the in‐situ moisture content at 30‐80 depth increased linearly R = 0.99) a rate corresponding 0.029 m 3 /m /%. The lab determined wilting point also char (R but much lower (0.003 /%). Biochar concentrations 2% density roots 40–80 interval. Addition 1% had most positive effect penetration resulting highest average (54% coverage compared 33% without biochar). This treatment resulted greatest spring grain (22%). Improving quality subsoils has global potentials, incorporation right amount correctly treated residues from bioenergy technologies such as is promising option.