绿洲膜下滴灌调亏对马铃薯土壤环境及产量的影响

为测定膜下滴灌调亏马铃薯全生育期内不同调亏水平土壤养分、土壤水热动态、生长动态、产量效应和水分利用效率,于2016年在河西荒漠绿洲灌区民乐县益民灌溉试验站开展了马铃薯不同生育阶段水分调亏灌溉的试验研究,结果表明,马铃薯膜下滴灌调亏土壤水热变化均匀且利用率高,有利于马铃薯对土壤养分的充分吸收和利用;土壤养分是土壤肥力的核心,是植物在生长发育过程中不可或缺的重要因素,膜下滴灌调亏栽培能有效减少土壤速效养分的流失,并提高马铃薯对土壤速效养分的利用效率;不同生育阶段马铃薯耗水量受水分调亏程度影响较大,其耗水量随调亏程度增大而显著减少(P0.05),水分调亏处理马铃薯全生育期总耗水量均低于全生育期充分灌水CK处理。块茎形成期轻度水分亏缺马铃薯水分利用效率、灌溉水利用效率、生物量均达到最大,较全生育期充分灌水显著提高29.04%,35.61%。因此,块茎形成期轻度水分亏缺灌溉方式能使马铃薯根区土壤始终保持湿润状态,有效减少渗漏损失和植株间无效蒸发损失,改善土壤水、肥和热量状况,有利于提高作物水分利用效率,且不显著降低马铃薯最终产量。

Effects of Regulated Deficit Irrigation on Soil Environment and Yield of Potato under Drip Irrigation in Oasis Region

In this paper,the experimental study of regulated deficit irrigation (RDI) of potato at different growth stages was carried out at Yimin Irrigation Experimental Station in Minle County in Hexi Oasis Region in 2016.The soil nutrient and soil water and heat in the different growth stages dynamics,growth dynamics,yield effects and water use efficiency were measured.The results showed that the water deficit of potato under drip irrigation was uniform and the utilization rate was high,which was beneficial to the full absorption and utilization of soil nutrient.The soil nutrient was the core of soil fertility and plant was indispensable in the growth and development.Regulated deficit irrigation under plastic film drip irrigation could effectively reduce the loss of soil available nutrients and improved the utilization efficiency of soil available nutrients.The water consumption of potato in different growing stages was affected by the degree of water deficit and the amount of water consumption decreased significantly with the increase of water deficit.The water consumption of potato during the whole growth period with regulation of water deficit was lower than that of full irrigation.It was found that the water use efficiency, irrigation water use efficiency of the potato were the highest during the tuber initiation with slightly water-deficit (WD1),and the water use efficiency,irrigation water use efficiency of the potato were 29.04%, 35.61% higher than that of CK control group with full irrigation all the time (CK control) significantly.Therefore,the medium water deficit irrigation in the tuber initiation stage could keep the soil in the potato root area moist all the time,effectively reduce the leakage loss and the evaporation loss between the plants,improve the soil water,fertilizer and heat status,and improve the crop water use efficiency,without significantly reducing the final tuber yield of potatoes.