Biochar preparation from Solidago canadensis and its alleviation of the inhibition of tomato seed germination by allelochemicals

Solidago canadensisis a malignant invasive plant widely distributed in China. In this study, it was used as a biomass source to prepare biocharvia an oxygen-limited pyrolysis method. The effect of temperature, heating rate and pyrolysis time on the yield and surface characteristics of the biocharwas identified. The adsorption properties for dimethyl phthalate(DMP), a typical allelochemical of Solidago canadensis, of the biocharwere explored. In addition, a pot experiment was conducted to reveal the effect of the biocharon tomato seed germination in the presence of allelochemicals. The maximum yield of the biocharwas observed when Solidago canadensiswas pyrolyzed at 300 °C for 2 h, with a heating rate of 8 °C min−1. Variation of pyrolysis conditions had little influence on the surface characteristics of the biochar. The adsorption of DMP on the biocharcould be well described by the Langmuir model, with a maximum adsorption capacity of 59.37 mg kg−1. The addition of biocharto the soil could promote tomato seed germination in the presence of allelochemicals. Therefore, the biocharprepared from Solidago canadensiscan be used for soil amendment for invaded sites.