设施番茄-黄瓜轮作体系适宜水氮管理和双氰胺调控模式研究

Study on Appropriate Water and Nitrogen Management and Dicyandiamide Regulation Model of Greenhouse Tomato-Cucumber Rotation System

本文采用田间小区试验法研究了不同水氮管理配施双氰胺(DCD)对设施番茄-黄瓜轮作体系经济效益及土壤基本理化性质的影响,探索适宜的番茄-黄瓜轮作水氮管理与DCD调控模式。结果表明:在番茄-黄瓜轮作体系中,与农民常规相比,减氮控水配施DCD处理在保证产量的前提下,节省全年总投入4600~6134 yuan/hm^(2),产投比增加4.29%~10.86%;设施番茄、黄瓜氮素利用率分别显著提高到31.41%、18.57%。设施番茄体系中,减氮控水配施DCD处理较农民常规氮肥农学效益提高了20.82%~61.04%,灌溉水农学效益增加了25.82%~40.20%。设施黄瓜体系中,减氮控水配施DCD处理化肥农学效益和灌溉水效益显著提高。其中,氮肥农学效益是农民常规处理的1.17~2.53倍;生育期内减氮控水配施DCD处理灌溉量较农民常规减少了33.87%,但灌溉水农学效益却提高了54.31%~63.79%。另外,减氮控水配施DCD还可在一定程度上减轻土壤酸化和盐分累积、增加土壤阳离子交换量。综合分析,设施番茄、黄瓜追施氮量分别为250 kg N/hm^(2)、380 kg N/hm^(2),同时配施10%DCD,并结合控水灌溉3200 m~3/hm^(2)、4100 m~3/hm^(2),可实现经济与环境双赢,是适宜的调控模式。

In this paper,a field plot experiment was carried out to study the effects of different water and nitrogen managements combined with dicyandiamide(DCD)application on the economic benefits and soil basic physical and chemical properties in the greenhouse tomato-cucumber rotation system,aiming to explore the appropriate water and nitrogen management and DCD regulation mode of greenhouse tomato-cucumber rotation.The results showed that compared with the conventional management treatment,the nitrogen reduction and water control combined with DCD treatment in the tomato-cucumber rotation system could save 4600~6134 yuan/hm^(2) of total annual investment,increase the input-output ratio by 4.29%~10.86%;and the nitrogen use efficiency of greenhouse tomato and cucumber was also significantly increased to 31.41%and 18.57%,respectively.In the greenhouse tomato system,the agronomic efficiencies of nitrogen and irrigation water in the nitrogen reduction and water control combined with DCD treatment was increased by 20.82%~61.04%and 25.82%~40.20%,respectively.Similarly,in the greenhouse cucumber system,the agronomic efficiencies of nitrogen and irrigation water in the nitrogen reduction and water control combined with DCD treatment were significantly improved,and the nitrogen agronomic efficiency was 1.17~2.53 times higher than that of the conventional management of farmers’treatment.During the growing period,compared with the conventional management treatment,the nitrogen reduction and water control combined with DCD treatment could reduce the amount of irrigation water by 33.87%,while the agronomic efficiency of irrigation water was increased by 54.31%~63.79%.In addition,the nitrogen reduction and water control combined with DCD treatment could also reduce soil acidification and salt accumulation,and increase the soil CEC content to a certain extent.In conclusion,the topdressing nitrogen applied at the rate of 250,and 380 kg/hm^(2),respectively,DCD was applied at the rate of 10%of applied nitrogen,and the amount of irrigation water was 3200 and 4100 m~3/hm^(2),respectively,which could achieve a win-win economic and environmental situation and is considered to be an appropriate regulation mode for the greenhouse tomato and cucumber.