本试验以日光温室秋冬茬番茄-冬春茬黄瓜轮作体系为研究对象,采用田间小区试验,研究了5季节水控肥(冬春茬黄瓜和秋冬茬番茄季N-P2O5-K2O总投入量分别为600-300-525 kg/hm2和450-225-600 kg/hm2)有机无机肥配施对0-40 cm(根区)土壤硝态氮供应、40-100 cm(根区以外)硝态氮残留和0-100 cm土体不同形态氮素淋失的影响,探索了设施蔬菜生产中节水节肥潜力,为构建设施蔬菜合理水肥管理下土壤肥力培育和土壤质量提升模式提供技术支持.试验结果表明,1)农民习惯水肥管理节水节肥潜力较大；节水控肥后0-100 cm土体硝态氮积累量、矿质氮和有机氮渗漏量均明显下降,种植蔬菜经济效益显著增加.2)商品有机肥猪粪与化肥在土壤无机氮供应方面的效果接近；节水控肥1/4～1/2猪粪氮替代1/4～1/2化肥氮后,0-40 cm土体硝态氮供应和40-100 cm土体硝态氮残留均无显著变化,但是随着猪粪氮配施比例的增加,土壤溶液渗漏量及养分淋失量呈增加趋势.3)施用秸秆促进了土壤无机氮固持,降低根区土壤硝态氮供应水平,提高土壤养分保蓄能力；节水控肥1/2秸秆氮替代1/2化肥氮后,0-40 cm土壤硝态氮供应量平均下降34.3％～56.2％,40-100 cm土体硝态氮残留量下降42.5％～87.8％,0-100 cm土体土壤溶液渗漏量下降65.0％,硝态氮淋失量下降82.0％,而产量和经济收入无显著差异.根据本试验结果,对于新建温室可采用单施化肥、化肥与猪粪配施方案,能在短时间内提高土壤无机氮供应强度,满足蔬菜氮素需求；对于种植了一段时间的温室,可采用冬春茬黄瓜季化肥配施猪粪—秋冬茬番茄季化肥配施秸秆方案,能固定积累于土壤中的无机氮,提高土壤养分容量,保证根层土壤氮素的稳定供应,降低环境风险,维护设施农业的可持续发展.%A long-term experiment of combined application of organic manure and chemical fertilizers was conducted to determine changes in soil NO3--N contents at depths of 0-40 cm (rhizosphere) and 40-100 cm,and leaching losses of mineral and organic N through 0-100 cm soil profile under water and fertilizer saving management (OPT management:N-P2O5-K2O application rates were 600-300-525 kg/ha for winter-spring cucumber and 450 -225-600 kg/ha for autumn-winter tomato) in winter-spring cucumber and autumn-winter tomato double cropping system.The results showed significant decreases of NO3--N contents in 0-100 cm soil profile and N leaching loss in leakage water,and distinct increases of economic incomes with the OPT management,indicating the huge water and fertilizer saving potentials in greenhouse vegetable production in farmer's conventional water and fertilizer management.There was no insignificant differences in soil NO3--N contents at depths of 0-40 cm during the growth period and 40-100 cm at the end of the growth period when 1/4-1/2 of chemical N was replaced by N from pig manure.With the increase ratio of pig manure N in the total applied N,leakage water volumes and N leaching tend to increase.When 1/2 of chemical N was replaced by N from straw,NO3--N contents in 0-40 cm soil and the residual NO3--N contents in 40-100 cm soil profile decreased by 34.3％-56.2％ and 42.5％-87.8％respectively,and leakage water volumes and NO3--N leaching amount decreased by 65.0％ and 82.0％,yields and economic incomes kept stable.For newly built greenhouses with lower nitrogen supply in soil,chemical fertilizers only or combined application of chemical fertilizers and pig manure are suitable.These pattern could increase soil N supply in a short time.For greenhouses used for serveral years with continuous cropping obstacles,the proper fertilizer management patterns used are combined application of chemical fertilizers and pig manure in winter-spring cucumber season and chemical fertilizers and straw in autumn-winter tomato season,which could immobilize excessive NO3--N in soils and decrease the risk of N leaching losses.
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