TY - CONF

T1 - Gasification Biochar Used as Soil Conditioner Positively Affects Physical Properties Known to Control Crop Yield And Nitrogen Leaching on Coarse Sandy Soil

AU - Hansen, Line Vinther

AU - Hansen, Emilie

AU - Petersen, Carsten Tilbæk

N1 - Conference code: 26

PY - 2018

Y1 - 2018

N2 - Sustainable crop production on coarse sandy soils is constrained by restricted root growth and poor water andnutrient retention. Amending with biochar can in some cases increase root depth and improve crop water supply but the mechanisms are not known in details. We added two low temperature, fine-grained gasification biochars (LTST and LTSN) and one fast pyrolysis biochar (FPST) to such soil at concentrations in the interval0-4wt% and investigated after thorough mixing in the lab their effects on the water retention curve and on soil compressibility. All the biochars increased water contents at equilibrium tension levels known to represent fieldcapacity (FC) and wilting point (WP). Available water capacity (θAWC=θFC-θWP) increased linearly over the whole range of concentrations. The effect of LTST and LTSN on AWC (on average 3.6 vol% per wt% biochar) was about 70% larger than the effect of the somewhat coarser FPST (2.1 vol% per wt% biochar). The compression index increased on average 21.2 kg m-3 per wt% of biochar regardless of type, showing that the soil became easier to compress with added biochar. Our results indicate that there is considerable potential for betterresource utilization and protection in crop production on coarse sandy soil by ameliorating the subsoil with finegrained gasification biochar or bioash from straw and other biomass.

AB - Sustainable crop production on coarse sandy soils is constrained by restricted root growth and poor water andnutrient retention. Amending with biochar can in some cases increase root depth and improve crop water supply but the mechanisms are not known in details. We added two low temperature, fine-grained gasification biochars (LTST and LTSN) and one fast pyrolysis biochar (FPST) to such soil at concentrations in the interval0-4wt% and investigated after thorough mixing in the lab their effects on the water retention curve and on soil compressibility. All the biochars increased water contents at equilibrium tension levels known to represent fieldcapacity (FC) and wilting point (WP). Available water capacity (θAWC=θFC-θWP) increased linearly over the whole range of concentrations. The effect of LTST and LTSN on AWC (on average 3.6 vol% per wt% biochar) was about 70% larger than the effect of the somewhat coarser FPST (2.1 vol% per wt% biochar). The compression index increased on average 21.2 kg m-3 per wt% of biochar regardless of type, showing that the soil became easier to compress with added biochar. Our results indicate that there is considerable potential for betterresource utilization and protection in crop production on coarse sandy soil by ameliorating the subsoil with finegrained gasification biochar or bioash from straw and other biomass.

M3 - Poster

T2 - European Biomass Conference and Exhibition

Y2 - 14 May 2018 through 18 May 2018

ER -