【摘 要】
：
延安地区属干旱、半干旱性气候,年平均降雨量500mm左右。该地土壤瘠薄,氨磷均严重缺乏。在农业生产的三大制约因子(薄、粗、旱)中,土壤瘠薄又是主要限制因子。所以增施肥料、
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延安地区属干旱、半干旱性气候,年平均降雨量500mm左右。该地土壤瘠薄,氨磷均严重缺乏。在农业生产的三大制约因子(薄、粗、旱)中,土壤瘠薄又是主要限制因子。所以增施肥料、培肥地力是农业生产之根本。“一次施肥”技术是顺应于该区气候特点、土壤特点和作物需肥特点而提出的一项旱地农业增产措施,在小麦生产中发挥了巨大的作用。在今后小麦生产由低产向高产的过渡中,提高“一次施肥”的质量标准并使之与农艺技术相配套则是非常关键的。
Yanan area is arid, semi-arid climate, the average annual rainfall is about 500mm. The soils are infertile and there is a serious shortage of ammonia and phosphorus. In the three major constraints of agricultural production (thin, rough, dry), infertility is the main limiting factor. Therefore, increasing fertilizers, fertilizing land fertility is the fundamental agricultural production. The “one-time fertilization” technology is a dry-farming yield-increasing measure that adapts to the climatic characteristics, soil characteristics and crop yield characteristics of the area, and has played a huge role in wheat production. In the future transition from low-yielding to high-yielding wheat production, it is crucial to improve the quality standard of “one-time fertilization” and make it compatible with agronomic technologies.
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