心土培肥改良白浆土的研究Ⅱ心土对作物产量的贡献及磷、钙培肥心土的效果

Research on Subsoil Fertilization of Albic Luvisol Improvement Ⅱ The Contrbution of Subsoil on the Crop Yield and Effect of Subsoil Fertilization with P and Ca

为明确心土对作物产量的贡献和P、Ca培肥心土的效果,采用盆栽试验与室内模拟试验相结合的方法,研究心土层对作物产量贡献和白浆土心土培肥的机理。结果表明:良好的心土层对作物产量影响十分明显。黑土厚度从20 cm增加到60cm,大豆增产40.4%;不同土层位置对大豆产量的贡献率分别为:20～40 cm土层10%以上,40～50 cm土层为4.57%;50 cm以下土层为1%。磷培肥后心土层吸附磷的能力降低、解吸率增加,土壤中有效磷含量提高;钙培肥后心土层土壤电导率和pH提高,但使土壤中磷的有效性降低;磷培肥后磷在土壤中主要转化为Ca2-P、Ca8-P、Al-P和Ca10-P。

The pot experiments and the indoor stimulation experiments were carried out for albic luvisol.Through the investagation of the contribution rate of subsoil,the effect and mechanism of subsoil fertilization on the albic luvisol were clarified.The results obtained from the experiments were as follows： Effect of better subsoil on yield of crop was obvious.Soybean yield increased 40.4% when the depth of black soil layer was from 20 to 60 cm.The contribution rate of different layers on soybean yield were： 20-40 cm soil layer was more than 10%,40-50 cm soil layer was 4.57%,and soil layers below 50 cm was 1%.The adsorption of P was reduced and desorption of P was increased after subsoil fertilizer with P,while available P was higer than before.EC and pH of subsoil are improved by fertilization with Ca.However,the effectiveness of P in the soil decreased.Subsoil fertilization with P mostly converted to Ca2-P,Ca8-P,Al-P and Ca10-P in subsoil.