Nitrogen Fertilizer Rates On Maize And The Dynamic Changes Of Nitrate And Ammonium In Soil

Hei Longjiang Province is an important grain base, handing a large number of grains to the state each year. But year after year,we only obtain nutrients from the soil without supplying, which makes black soil is short of nutrient. Therefore, we have to increase nitrogen fertilization to make sure the production every year, but the amount of fertilizer has not been scientifically controlled areas, so the excess nitrogen fertilizer remained in the soil will bring not only the pollution of surface water and groundwater, but also the addition of residual nitrogen in the soil. Basal fertilizer seems not so important, because the amount of basal fertilizer will not affect the growth of the maize. Therefore, fertilizing top dressing disposably can reduce labor and increase economic benefits, at the same time, cause no cuts. The purpose of this article is to measure the amount of the residual nitrogen in the soil in different periods, different soil depth and different nitrogen treatments to determine which treatment the fertilizer is excess. In this article, we use randomized block design, nitrogen, phosphorus and potassium are treated as top dressing, among them, nitrogen fertilizer is applied in four levels, phosphorus and potassium are applied to the fixed amount. Fertilization is not the way in the past, but the use of fertilizer is divided. In other words, the fertilizer is applied in this furrow, then the furrow next to it will not apply fertilizer. Respectively, the jointing stage, tasseling stage and mature stage takes 0-30 cm, 30-60 cm, 60-90 cm solums of soil to the laboratory to test the amount of nitrate nitrogen and ammonium nitrogen. We should pay more attention to the way taking soils, in each plot, we have to take two kinds of soils, which the one fertilize near the ridge and the other one apart from the no fertilized ridge. Each solum, each ditch takes soil, each one repeated three times, respectively, mixing the soil between each repetition. Conclusions: 1. In terms of the residual ammonium nitrogen in the soil, the amount of nitrogen fertilization and its growth stages are significant differences with ammonium nitrogen, while sampling depth has little effect on the ammonium nitrogen; 2. In terms of the residual nitrate nitrogen in the soil, the amount of nitrogen fertilization, its growth stages and sampling depth are significant differences with nitrate nitrogen; 3. In jointing stage, each of the solum shows dramatic changes from the third processing to the fourth treatment, which indicates the application of nitrogen fertilizer in the fourth treatment is excess. While in the tasseling stage, ammonium nitrogen in each of the solum shows fault during the second, the third treatments; 4. In jointing stage, 0-30 cm soil nitrate nitrogen in the third and fourth treatment shows dramatic increase, so we can indicate the nitrogen fertilization in the fourth treatment is excess; 5. In tasseling stage, the nitrate nitrogen in each solum shows fault from the second to the third treatment; 6. In maturity stage,the depth of 60-90 cm of the nitrate nitrogen shows dramatic increase from the third to the fourth treatment, so we can indicate the nitrogen fertilization of the fourth treatment is excess; 7. In maturity stage, the ammonium nitrogen and nitrate nitrogen in the soil shows low correlation with the sampling depth and the amount of nitrogen fertilization, because with the maturity of the maize kernels, each depth of the soil, nutrients in soil are gradually absorbed by plants.