控释配方肥氮素在芥菜连作期的去向和平衡

采用小型渗漏计，在施用水溶性肥料及其与控释肥料组成的控释配方肥条件下，研究了3个生长季连作芥菜的吸氮量、N₂O排放损失、氮素淋溶损失、氮素残留和其他损失量.结果表明： 在含25%控释氮素的控释配方肥处理下，芥菜的吸氮量逐季增加，后期显著高于水溶性肥料处理.水溶性肥料处理的N₂O累积排放量和氮素淋溶损失量明显高于控释配方肥处理，各肥料处理氮素淋失的形态均以NO₃^--N为主.相对于水溶性肥料，控释配方肥能改变氮素的去向，氮素吸收利用率提高75.4%，土壤残留增加76.0%，淋溶损失和其他表观损失分别减少27.1%和66.3%.施用控释配方肥是减少氮素各种形式损失、显著提高氮肥利用率的有效途径，控释肥料是氮素养分高效利用的环保型肥料.

Fate and balance of bulk blending controlled release fertilizer nitrogen under continuous cropping of mustard

Under the conditions of applying water soluble fertilizer and its bulk blending with controlled release fertilizer (BB-CRF), and by using micro-lysimeter, this paper quantitatively studied the nitrogen (N) uptake by mustard, the soil N losses from N₂O emission, leaching and others, and the N residual in soil in three rotations of continuously cropped mustard. In the treatment of BB-CRF with 25% of controlled release nitrogen, the N uptake by mustard increased with rotations, and the yield by the end of the experiment was significantly higher than that in the treatment of water soluble fertilizer. The cumulated N₂O emission loss and the Neaching loss were obviously higher in treatment water soluble fertilizer than in treatment BB-CRF. NO₃^--N was the primary form of N in the leachate. In relative to water soluble fertilizer, BB-CRF altered the fates of fertilizer nitrogen, i.e., the N uptake by mustard and the N residual in soil increased by 75.4% and 76.0%, and the N leaching loss and other apparent N losses decreased by 27.1% and 66.3%, respectively. The application of BB-CRF could be an effective way to reduce the various losses of fertilizer N while increase the fertilizer N use efficiency, and the controlled release fertilizer is the environmentally friendly fertilizer with the property of high N use efficiency.