Soil quality improvement a b s t r a c tThermal gasification of various biomass residues is a promising technology for combining bioenergy production with soil fertility management through the application of the resulting biochar as soil amendment. In this study, we investigated gasification biochar (GB) materials originating from two major global biomass fuels: straw gasification biochar (SGB) and wood gasification biochar (WGB), produced by a Low Temperature Circulating Fluidized Bed gasifier (LT-CFB) and a TwoStage gasifier, respectively, optimized for energy conversion. Stability of carbon in GB against microbial degradation was assessed in a shortterm soil incubation study and compared to the traditional practice of direct incorporation of cereal straw. The GBs were chemically and physically characterized to evaluate their potential to improve soil quality parameters. After 110 days of incubation, about 3% of the added GB carbon was respired as CO 2 , compared to 80% of the straw carbon added. The stability of GB was also confirmed by low H/C and O/C atomic ratios with lowest values for WGB (H/C 0.12 and O/C 0.10). The soil application of GBs exhibited a liming effect increasing the soil pH from ca 8 to 9. Results from scanning electron microscopy and BET analyses showed high porosity and specific surface area of both GBs, indicating a high potential to increase important soil quality parameters such as soil structure, nutrient and water retention, especially for WGB. These results seem promising regarding the possibility to combine an efficient bioenergy production with various soil aspects such as carbon sequestration and soil quality improvements.

No abstract

16Gasification biochar (GB) contains recalcitrant carbon that can contribute to soil carbon sequestration 17 and soil quality improvement. However, the impact of GB on plant-available water capacity (AWC) 18 and plant growth in diverse soil types still needs to be explored. 19 A pot experiment with spring barley (Hordeum vulgare L.) was conducted to investigate the effect of 20 soil amendment by 1 % straw and wood gasification biochar (SGB and WGB), respectively, on AWC 21 and plant growth responses under two levels of water supply in a temperate sandy loam and a coarse 22 31 32 structure 35 3 36 Abbreviations 37 GB Gasification biochar 38 SGB Straw gasification biochar 39 WGB Wood gasification biochar 40 AWC Plant-available water capacity 41 WHC Water holding capacity 42 43 4

No abstract

No abstract