腐植酸对土壤理化性质及洋葱产量的影响

Effects of Humic Acid Application on Soil Physical and Chemical Properties and Onion Yield

为了改善耕地质量、减量施用化学肥料,开展了腐植酸应用田间试验。试验设4个处理,分别为:T_(1)常规施肥、T_(2)常规施肥+600 kg/hm^(2)腐植酸、T_(3)常规施肥+1200 kg/hm^(2)腐植酸、T4常规施肥+1800 kg/hm^(2)腐植酸,研究了不同用量腐植酸对河西走廊灌漠土理化性状、重金属生物有效性及洋葱产量的影响。结果表明:灌漠土耕层中施入腐植酸后,与常规施肥相比,土壤pH值降低0.27%~0.69%,容重降低3.5%~6.9%,有机质、碱解氮、速效磷、速效钾分别提高3.3%~4.7%、8.6%~23.7%、7.6%~21.1%、15.9%~36.5%,洋葱增产3.5%~5.3%;施入不同量的腐植酸,可不同程度地降低土壤中重金属生物有效性,有效铅、有效锌、有效铜、有效镉分别较对照降低了17.7%~18.5%、4.4%~13.7%、39.5%~44.7%、17.1%~35.8%。可根据不同土壤特点和腐植酸特性,制定相应合理施肥方案。

In order to improve the quality of cultivated land and reduce the application of chemical fertilizer,a field experiment of humic acid application was carried out.Four treatments were set in the experiment,T_(1) was conventional fertilization,T_(2) was conventional fertilization+600 kg/hm^(2) humic acid,T_(3) was conventional fertilization+1200 kg/hm^(2) humic acid,T4 was conventional fertilization+1800 kg/hm^(2) humic acid.The effects of humic acid on soil physicochemical properties,bioavailability of heavy metals and onion yield of irrigation desert of Hexi Corridor were studied.The results showed that after the application of humic acid,the soil pH value decreased by 0.27%-0.69% compared with conventional fertilization,the bulk density of soil decreased by 3.5%-6.9%,the organic matter,alkali hydrolyzable nitrogen,available phosphorus and available potassium and yield increased by 3.3%-4.7%,8.6%-23.7%,7.6%-21.1%,15.9%-36.5% and 3.5%-5.3%,respectively.The availability of heavy metals in soil could differtntly reduced by applying different amounts of humic acid,the available lead,available zinc,available copper and available cadmium decreased by 17.7%-18.5%,4.4%-13.7%,39.5%-44.7% and 17.1%-35.8%,respectively.The corresponding rational fertilization program could be formulated according to different soil characteristics and humic acid characteristics.