农田中氮肥的损失与对策

评述了我国有关农田中氮肥的损失及其对策的研究结果。主要涉及农田中氮肥的损失程度、途径和机理；氮肥损失对环境的影响；减少氮肥损失、提高氮肥利用率的技术原则和主要措施。这些措施包括确定适宜的施氮量，以及采用深施、水肥综合管理、平衡施肥、脲酶抑制剂、硝化抑制剂、液态分子膜等。

Loss of Fertilizer N from Plants-soil System and the Strategies and Techniques for Its Reduction

The present paper summarizes the studies conducted in China relevant to the improvement in the efficiency of fertilizer N by reducing N losses from crop plant-soil systems. It includes those topics such as the extent, pathways and mechanisms of fertilizer N losses from soil-plant systems, the agronomic efficiency of fertilizer N and the environmental impact of N loss, and the principles and techniques for reducing N loss and improving N efficiency. The efficacy of optimization of the rate and timing of N application, deep placement, irrigation-fertilization, urease inhibitors, nitrification inhibitors, and surface film for reducing ammonia loss from flooded rice fields are thoroughly discussed.