冬小麦表施尿素畦灌下土壤水氮分布试验研究

Experimental study on spatial distribution of soil water and inorganic nitrogen under border irrigation after scattering urea

基于冬小麦生长期表施尿素畦灌下获得的田间试验结果,对不同入畦单宽流量和施肥量下土壤水氮空间分布状况及变化趋势开展研究,评价作物有效根系层土壤水氮贮存效率及其沿畦长分布均匀性,探讨适宜的施肥灌溉模式。结果表明,灌后2d土壤水分均布在0～100cm土层,而土壤硝态氮则聚集在0～40cm土层,土壤水分空间分布差异明显小于土壤硝态氮,作物有效根系层土壤硝态氮贮存效率明显高于土壤水分,表施尿素畦灌下的土壤水氮空间分布同步性并不明显。入畦流量和施肥量对作物有效根系层土壤水氮贮存效率和均匀度影响较为明显,高施肥大流量下作物有效根系层土壤水氮贮存效率及其沿畦长分布均匀性明显高于低施肥小流量下的相应值。

Based on the field experiments for border irrigation after scattering urea in the growing season of winter wheat,the distribution of soil water and nitrate before and after irrigation 2d under different inflow rate and amount of fertilizing were analyzed,meanwhile the storage efficiency in the crop root zone and the uniformity along basin length for soil water and nitrate were evaluated.The results show that,2 days after irrigation the soil water are basically distributed in the 0-100cm soil depth,while the soil nitrate were concentrated in the 0-40cm soil depth.The spatial distribution difference of soil water is far less than the soil nitrate,however,in the crop root zone the storage efficiency of soil nitrate is signiticantly higher than the soil water.Under the condition of border irrigation after scattering urea,the synchronism of spatial distribution between the soil water and fertilizer is not obvious.The influence of inflow rate and amount of fertilizing on storage efficiency of water and fertilizer in the effective crop root zone and the distribution uniformity is significant.Under the strategy of large inflow rate and high amount of fertilizing the storage efficiency of water and fertilizer in the effective crop root zone and the distribution uniformity of water and fertilizer along the basin length is better than that under the strategy of small inflow rate and low amount of fertilizing.