通过分析干旱区农业特点和过去几十年世界粮食增产的原因，讨论了长期施用化肥对作物产量和土壤肥力的影响、施用化肥培肥土壤的机理，以及施用化肥的效益，提出了干旱区生态农业建设要注重土地内涵的发展，建立物质、能量和不断扩大养地用地的良性循环，而这些都必须增加化肥的投入。 By analyzing the characteristics of agriculture in arid areas and the reasons for increasing grain output in the world during the past few decades, the effects of long-term application of chemical fertilizers on crop yields and soil fertility were discussed. The mechanism of applying fertilizers to fertilize soils and the benefits of applying fertilizers were discussed. The construction of agriculture should pay attention to the development of the connotation of land, establish a virtuous cycle of material and energy and continuously expand the land for raising land, and all of these must increase the input of fertilizer.