Production Status And Application Evaluation Of Liquid Fertilizer In A Facility Vegetable Garden In The Suburbs Of Beijing

In order to discuss the current situation of vegetable production in Beijing suburbs and the nutrient release of double-effect inhibitors in liquid nitrogen fertilizer UAN,and the effects of drip irrigation techniques on the growth and environmental effects of lettuce.The research is divided into three parts: First,in May-July 2018,the investigation on the status quo of five vegetable production parks in suburban counties in Beijing was carried out;Second,in July and August 2018 in Beijing Agriculture and Forestry The Academy of Sciences carried out an indoor culture experiment on the release of soil nutrients from different doses of double-effect inhibitors in liquid nitrogen fertilizer UAN.Third,the field experiment on the effects of liquid fertilizer drip fertigation on the growth and environmental effects of lettuce in September-December 2018.The survey was conducted in the form of on-site investigation and filling out questionnaires.The indoor culture experiment was set up with 7 inhibitor additives,and the addition amount of double-effect inhibitors was pure.0,0.25%,0.5%,1.0%,1.5%,2.0% of nitrogen,no fertilizer for control(CK),10 times for each treatment;three treatments for field experiment,optimized fertilization mode for liquid fertilizer(LF)The conventional fertilizer fertilization mode(CF)and non-nitrogen fertilizer(CK)treatment were completely randomized block design.The results show that:(1)The number of workers aged 50 or older in the facility vegetable garden in Beijing accounts for 78.3% of the total number of workers,and the aging trend is obvious.Among the 20 parks,the management of water and fertilizer is extensive,and there is almost no quantitative concept.There are 11 workers whose wages are above 100 yuan/day/person,of which the highest wage is 140 yuan/day/person,and the labor input cost is relatively large.In the survey of vegetable gardens,the proportion of pollution-free,green and organic production methods is 60%,30%,and 10% respectively.The production area of green and organic vegetables is insufficient,and the production potential of high-quality vegetables is large and needs to be improved.In the use of light simplification technology,such as small mechanical transplanter has a degree of 0%,ridge machine ownership of 5%,water and fertilizer integrated application of 90%,in addition to drip fertigation,the use of light simplification,mechanization technology is rarely,In the research park,the management of the park has a strong demand for light and simplified technology,and the demand level is 100%,indicating that the development of light and simplified technology is urgently needed in the production of facilities.(2)Adding a double-effect inhibitor to the liquid fertilizer UAN has a significant dose effect,and the effective action time is 10 days.When the dose of the double-effect inhibitor added to the liquid nitrogen fertilizer UAN is 0.5% of pure nitrogen,a suitable nutrient release rule can be provided,and a low cost input can be maintained.(3)The optimized fertilization mode of liquid fertilizer reduced the yield of 15% of nitrogen fertilizer compared with the conventional fertilization mode,and significantly reduced the ammonia volatilization and nitrous oxide emission of the soil,and the emission reduction rate reached 24.6% and 21.6%,at the same time,improved fertilization efficiency,reduced soil nitrate nitrogen residue,and increased nitrogen fertilizer utilization rate by 2.37%.