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近年来我国化肥用量虽然大幅度增加,但出现了化肥报酬递减的趋势。人们对长期施用化肥后土壤的理化性质极为关注,然而对土壤中微量元素的变化却很少注意。本文通过对上海地区青紫泥类型土壤的四年肥料定位试验,探讨了土壤中微量元素含量的变化及各种营养元素的平衡供应等问题。一、试验方法及测定本试验在青浦县朱家角进行。供试土壤的主要理化性质(见表1)。土壤为中性,泥炭层位高而且厚度大。该土壤含铁量相当高
In recent years, although the amount of chemical fertilizer in our country has increased substantially, the trend of declining fertilizer returns appears. People pay great attention to the physical and chemical properties of soil after long-term application of fertilizers, but little attention has been paid to the changes of trace elements in soil. In this paper, the four-year fertilizer locating experiment of brucite-type soils in Shanghai was carried out to investigate the changes of trace elements in soils and the balanced supply of various nutrients. First, the test methods and determination The test was carried out in Zhujiajiao, Qingpu County. The main physical and chemical properties of the soil tested (see Table 1). The soil is neutral and the peat horizon is high and thick. The iron content of the soil is quite high