木醋液熏蒸对大棚土壤及西瓜生长的影响

Fumigation with Wood Vinegar: Effects on Soil and Watermelon Growth in Greenhouse

木醋液是生物质热裂解过程中的烟气液化而形成的液体,作为土壤熏蒸剂的作用与效果目前还没有数据。本研究将不同量木醋液喷施于大棚土壤,并以溴甲烷为对照,观测其抑菌作用及其对西瓜生长的影响。结果表明:喷施750~3000 kg/hm^2木醋液,土壤pH值降低了0.10~0.31个单位,矿质氮无显著的变化,可培养细菌、真菌和放线菌分别提高了101%~132%、38%~204%和10%~58%,而镰孢菌和疫霉菌分别降低了64%~316%和12%~38%。比起溴甲烷,木醋液尽管对土壤微生物区系的负面影响很小,但杀灭病原菌的作用不仅很微弱,且时效也很短;还可能抑制土壤有机氮矿化,降低土壤矿质氮含量,施用量过大会降低西瓜产量,显然,木醋液作为设施大棚土壤熏蒸剂的价值很低。

Wood vinegar is a substance formed from the liquefaction of flue gas during biomass pyrolysis process.Currently,there is no data about the roles of wood vinegar as a soil fumigant.We sprayed different volumes of wood vinegar on soil in greenhouse,took methyl bromide as a control to observe its antibacterial activity and effect on watermelon growth.The results showed that:soil pH value reduced by 0.10-0.31 units,while mineral nitrogen had no significant change with spraying 750-3000 kg/hm^2 wood vinegar;in addition,the amounts of culturable bacteria,fungi and actinomycetes increased by 101%-132%,38%-204%and 10%-58%;both Fusarium and Phytophthora are reduced by 64%-316%and 12%-38%,respectively.Compared with methyl bromide,wood vinegar had weaker and shorter impacts on pathogens though having less negative effect on soil microflora;moreover,nitrogen mineralization might be partially inhibited and thus induced low content of soil mineral nitrogen;spraying too much wood vinegar would reduce the yield of watermelon.In conclusion,wood vinegar has a low value as a fumigant in the greenhouse soil.