农业机械学报2017，Vol.48Issue(8)：219-228,10.DOI:10.6041/j.issn.1000-1298.2017.08.025
土壤容重对涌泉根灌土壤水氮运移特性的影响
Effects of Soil Bulk Density on Transport Characteristics of Water and Nitrogen under Bubbled-root Irrigation
摘要
Abstract
The different soil bulk density levels (1.35 g/cm3,1.40 g/cm3,1.45 g/cm3 and 1.50 g/cm3)were constructed by indoor manual configuration.The experiment of water and fertilizer infiltration was carried out in the soil bin.The effects of soil bulk density on cumulative infiltration,wetting front migration,soil moisture,NH4+-N and NO3--N transport were investigated.An empirical model was created,in which the cumulative infiltration amount and the wetting front migration distance were the dependent variables,and the bulk density and infiltration time were independent variables.Results showed that the soil bulk density had a significant effect on the cumulative infiltration,the migration distance of wetting front and the distribution and transformation of moisture and nitrogen in the soil.With the decrease of soil bulk density,the cumulative infiltration,wetting front migration,moisture in the body,NH4+-N and NO3--N contents showed an increasing trend.The greater the soil bulk density was,the smaller the infiltration coefficient K became.The greater the soil bulk density was,the greater the infiltration index α became.At the same time,the average value,the change amount and the conversion rates of NH4+-N and NO3--N in wetted body were increased with the increase of soil bulk density.The closer the distance to the emitter was,the higher the contents of NH4+-N and NO3--N became.The distribution of NH4+-N in the moist body was mostly concentrated in the vicinity of the emitter.With the redistribution,the content of NH4+-N in the wetted soil and the conversion rate were decreased gradually,and the transformation amount was increased gradually.After the redistribution for 3 d,5 d,10 d,15 d and 20d,with the end of irrigation time as the benchmark,the decline order was 2.34％,11.41％,34.22％,59.06％ and 73.75％,respectively.The distributions of NO3--N in the soil were similar to water.After the redistribution for 3 d,5 d,10 d,15 d and 20 d,with the end of irrigation time as the benchmark,the NO3--N content increase order was 0.76％,60.12％,156.95％,204.68％ and 180.51％,respectively.The soil bulk density had a significant effect on the distribution and transformation of moisture and nitrogen in the soil.关键词
涌泉根灌/土壤容重/再分布/模型/氮素运移Key words
bubbled-root irrigation/soil bulk density/redistribution/models/nitrogen migration分类
农业科技引用本文复制引用
费良军,刘显,王佳,曾健,杨扬..土壤容重对涌泉根灌土壤水氮运移特性的影响[J].农业机械学报,2017,48(8):219-228,10.基金项目
国家重点研发计划项目(2016YFC0400204)、国家自然科学基金项目(51279157、51479161)和公益性行业(农业)科研专项(201203003) （2016YFC0400204）
