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塿土是我国黄土高原地区农业历史悠久的耕种土壤之一,是我国粮棉生产的重要基地。 磷肥在塿土中的施用,在解放前后大多数认为磷肥增产效果不明显,甚至于以否定,1953年以后少数资料认为有增产效果。近年来,磷肥肥效表现出增产的趋势,但肥效往往不稳定。目前,随着高产品种的推广及大量施用氮素化肥,由此对磷肥的要求日益迫切。过去,对塿土磷素进行过一些研究,但是,多数研究者集中在关中西部的油塿土上,对其它土壤,特别是高度培肥的塿土,磷素资料十分缺乏。为了合理
Loess Plateau is one of the cultivated soils with a long history of agriculture in the Loess Plateau, and an important base for the production of grain and cotton in our country. The application of phosphate fertilizer in clay soil, before and after liberation, most of them believed that the effect of increasing phosphorus fertilizer yield was not obvious. Even with the negative result, a small number of data after 1953 were considered to have the effect of increasing yield. In recent years, the efficiency of phosphate fertilizer shows an increasing trend, but the efficiency of fertilizer is often not stable. At present, with the popularization of high-yielding varieties and the large-scale application of nitrogenous fertilizers, the requirements for the phosphate fertilizer are becoming more and more urgent. In the past, some studies on stratum phosphorus had been conducted. However, most of the researchers focused on the stratum in the western part of the Guanzhong area and lacked data on the contents of other soils, especially highly fertilized stratum and phosphorus. To be reasonable