Effects of Different Fertilization Schemes on Vegetable Yield and Nitrogen Loss from Vegetable Fields

Field plot trials with amaranth,brassica chinensis,and eggplant involving 6 different fertilization schemes including non-fertilizer,chemical fertilizer,optimal fertilizer(combined chemical fertilizer and organic manure),organic manure,increased N fertilizer,increased P fertilizer,were conducted under natural rain-fed condition to investigate the effects of the fertilization schemes on yield,as well as N accumulation,nitrogen fertilizer utilization rate,and loss of N by surface runoff.The results show that compared with non-fertilizer,the other 5 fertilization models can increased yield of 93.55%,103.74%,96.68%,130.78% and 136.04%,respectively.With different fertilization,the loss of total N by surface runoff varied between 68.11~92.10 kg/hm2.Compared with the chemical fertilization,organic fertilization and optimum fertilization could decreased total N loss by 4.67% and 2.02% respectively.Compared with the optimal fertilizer,increasing N and P fertilizer could increase the amount of total N loss respectively by 10.53% and 8.28%.Therefore,the fertilizer ratio should be improved to effectively reduce nitrogen loss on vegetable lands.With steady inputs of N and P,organic fertilizer should be increased while chemical fertilizer should be reduced.