Effect of fertilization pattern on yield and nitrate content of vegetables, and loss of nitrogen and phosphorus in simulated soil column.

A fertilization experiment was carried out on two cropping of vegetables growing in simulated soil column.The experiment was designed to have 7 fertilization patterns [i.e.(1)CK or no fertilizer,(2)chemical fertilizer applied as basal dressing,(3)chemical fertilizer applied half as basal dressing and half as side-dressing,(4)chemical fertilizer and dicyandiamide applied as basal dressing,(5)chemical fertilizer and dicyandiamide applied half as basal dressing and half as side-dressing,(6)chemical fertilizer and organic manure(half and half on N basis),and(7)organic manure applied as basal dressing] to test effect of different fertilization patterns on yield and nitrate content of the vegetables,and loss of nitrogen and phosphorus from the simulated soil column.Results show that Pattern 4 and Pattern 7 not only produced higher yield of vegetables that were lower in nitrate content,but also significantly reduced leaching loss of nitrate-nitrogen,ammonia-nitrogen and water-soluble phosphorus from the soil column.Consequently,the findings can be used to effectively alleviate agricultural non-point source N and P pollution from vegetable fields to underground water bodies.