水肥一体化减量施肥对坡地烤烟肥料利用率及土壤养分平衡的影响

Effects of Water and Fertilizer Integration with Reduced Fertilization on Fertilizer Utilization Rate and Soil Nutrient Balance of Flue-cured Tobacco on Slope Land

【目的】为探寻南方烟区坡地烤烟水肥一体化减量施肥管理模式。【方法】以当地常规水肥管理为对照,研究了水肥一体化减量施肥对坡地烤烟干物质积累、氮钾吸收与分配、肥料利用率及土壤养分平衡的影响。【结果】两年的试验结果显示,应用水肥一体化管理的烤烟,在肥料减量的情况下,其干物质积累、氮钾吸收量仍然高于对照,且显著提高了肥料利用率,降低了养分盈余和平衡系数。水肥一体化肥料减量20%的T2处理,成熟期干物质积累比常规水肥管理年均增加22.28%,伸根期对氮钾吸收促进最显著,分别比CK提高92.64%和83.23%。T2处理的氮肥表观利用率、当季回收率和经济利用率分别比CK增加20.98、14.6和8.6个百分点,比肥料等量的T1处理还高15.25%、16.15%和17.64%,钾肥偏生产力平均增加35.02%,表观利用率、当季回收率和经济利用率与CK的最大差异出现在2017年,达80.62%、105.6%和126.03%。从土壤养分平衡来看,水肥一体化模式增加了作物携出量、降低了养分盈余,减量施肥的T2、T3处理与CK相比,氮素盈余量分别降低49.3和54.6 kg·hm^-2,养分平衡率下降93.85和103.16个百分点;钾素平衡以T2表现最优,盈余量比CK减少86.69 kg·hm^-2,平衡率下降158.75个百分点。【结论】综上所述,水肥一体化管理模式下,坡地烤烟种植适当减少肥料用量、增加追肥比例,可以提高肥料利用率、降低土壤养分盈余。

【Objective】The present paper aimed to explore suitable water and fertilizer integration with reduced fertilization mode for fluecured tobacco production on slope land in southern tobacco-growing areas.【Method】Taking the local conventional water and fertilizer management as a comparison,the effects of water and fertilizer integration on dry matter accumulation,N and K absorption and distribution,fertilizer utilization rate and soil nutrient balance of flue-cured tobacco on slope land were studied.【Result】Results of two-year experiment showed that the dry matter accumulation,nitrogen and potassium absorption of flue-cured tobacco with water and fertilizer integrated management were still higher than those of control when fertilizer was reduced,and fertilizer utilization ratio significantly increased,and the nutrient surplus and balance coefficient were reduced.T2 treatment with 20%reduced fertilization increased the dry matter accumulation by 22.28%in maturing stage than that of conventional treatment,and promoted the absorption of nitrogen and potassium by 92.64%and 83.23% respectively in root extending stage.The apparent utilization rate,season recycling rate and economic utilization rate of nitrogen fertilizer of T2 treatment increased by 20.98%,14.6% and 8.6% respectively compared with CK,even 15.25%,16.15% and 17.64% higher than T1 treatment with the same amount fertilizer.Fertilizer productive efficiency of potassium increased by 35.02%on average,and the biggest difference of apparent utilization rate,season recycling rate and economic u2027 tilization rate between T2 and CK appeared in 2017,reaching 80.62%,105.6%and 126.03%.From the soil nutrient balance,water and fertilizer integration mode increased crop carrying capacity and reduced nutrient surplus.Compared with CK,T2 and T3 treatments reduced nitrogen surplus by 49.3 and 54.6 kg·hm^-2,and the nutrient balance rate decreased 93.85 and 103.16 percentage points.The best performance on potassium balance was T2 treatment,it’s potassium surplus decreased by 86.69 kg·hm^-2 compared with CK,and the balance rate fell 158.75 percentage points.【Conclusion】In conclusion,under the water and fertilizer integration mode,it can improve the fertilizer utilization rate and reduce the soil nutrient surplus by properly reducing the fertilizer consumption and increasing the topdressing ratio.