The Spatio-temporal Variations of Soil NO-3-N and Apparent Budget of Soil Nitrogen Ⅱ. Summer Maize
土壤硝态氮时空变异与土壤氮素表观盈亏Ⅱ.夏玉米

To minimize the loss and residual rate of soil NO - 3-N, the rate, time and method of nitrogen fertilization must be fitted to the crop needs and uptake capacity. Therefore, the spatio-temporal variations of soil NO - 3-N and apparent budget of soil N in summer maize were studied under different nitrogen fertilizer (Nf) level. A field trail was conducted at Wuqiao Research Station, Wuqiao county, Hebei province in 1998. The experiment was laid out in a split-plot design, 5 doses of nitrogen were in the...