不同覆土厚度对裸岩石砾地土壤理化性状和冬小麦产量的影响

目的]为了揭示在裸岩石砾地通过不同覆土厚度作物耕作层土壤理化性状及冬小麦产量的变化。方法]2011～2012年在陕西富平基地设置了在裸岩石砾地,通过30 cm(C30)、40 cm(C40)、50 cm(C50)、60 cm(C60)、80 cm(C80)和100 cm(C1000)等6种不同覆土厚度,分析不同覆土厚度下土壤容重、土壤养分和冬小麦产量的差异。结果]不同覆土厚度对耕作层土壤容重和土壤孔隙度的影响差异显著(P0.05),且以C50处理效果最佳;与C30、C40、C60、C80和C100处理相比,C50处理0～40 cm土层平均土壤容重降幅达到1.01%～2.64%;平均土壤孔隙度最大,为33.19%。不同覆土厚度对土壤0～50 cm土层的土壤碱解氮、速效磷和速效钾含量具有明显的影响;碱解氮、速效磷和速效钾含量都随着土层深度的增加而减小。在0～50 cm土层中,C50处理土壤平均碱解氮含量分别比C60、C80和C100处理高12.18%、11.93%和17.49%;在10～30 cm土层C40处理土壤的速效磷含量明显高于其他处理;C50处理能有效提高0～10 cm土层的土壤速效钾含量,C40处理能有效提高10～30 cm土层土壤速效钾含量,即C50处理较其他处理具有保肥作用。不同处理对冬小麦产量、产量构成因素的影响显著,以C50处理平均籽粒产量最高,为6 474.02 kg/hm2,与其他处理之间差异显著(P0.05)。结论]C50处理具有保肥作用且增产效果最佳。

Effects of Different Depth of Soil Thickness on Soil Physiochemical Properties and Winter Wheat Yield on Barren Gravel Land for Land Reclamation

Objective] The research aimed to investigate the effects of different soil thickness on soil physiochemical properties and winter wheat yields.Method]A continuous winter field experiment of six different soil thickness treatments,which included thirty cm（C30）,forty cm（C40）,fifty cm（C50）,sixty cm（C60）,eighty cm（C80） and hundred cm（C100） were conducted at Fuping County,Shaanxi Province in 2011-2012.Soil bulk density,soil nutrient and winter wheat yield under different soil thickness treatments were analyzed.Result] The soil bulk density and soil porosity of the plough layer were different（P 0.05） and the effect of C50 treatment was the highest.Compared with C30,C40,C60,C80 and C100 treatment,the average of soil bulk density decreased from 1.01% to 2.64% and the average of soil porosity was 33.19%,the highest one in 0-40 cm soil layer respectively under C50 treatment.The hydro-N,available P and K content were significantly different in 0-50 cm soil layer under different soil thickness.The content decreased with the increase of the soil layer.Compared with C60,C80 and C100 treatment,the average of hydro-N content increased by 12.18%,11.93% and 17.49% in 0-20 cm soil layer under C50 treatment.The average of available P content was significantly higher than others in 10-30 cm soil layer under C40 treatment.The available K content increased in 0-10 cm soil layer under C50 treatment and increased under C40 treatment in 10-30 cm soil layer.Compared with other treatments,the soil fertilization effects of C50 treatments were significantly higher.Compared with other treatments,C50 treatment was significantly different and the grain yield of C50 treatments was the highest one under the different soil thickness.Conclusion] C50 presented best on fertilizer conservation and yield-increasing effect.