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水稻是对肥料最敏感的作物之一。在苏联各地区的试验中,水稻施用氮肥的增产幅度为3.5—27.9公担/公顷。但尽管氮肥有较高的肥效,植物对氮肥的利用率却并不高(17—45%)。甚至在大量施用氮肥的情况下,水稻产量中总氨量的50%以上为土壤氮。稻田土淹水时,还原过程增强,硝化细菌的活动局限在水稻根际和与水接触的一薄层土壤中。但在种植水稻的秧苗期,土壤中必然会有氧化和还原过程交替发生,氮素可能因硝化和反硝化而损失。
Rice is one of the most sensitive crops to fertilizer. In the experiments in various regions of the Soviet Union, the rate of increase in nitrogen application by rice was 3.5-27.9 hectares / hectare. However, although nitrogen fertilizers have higher fertilizer efficiency, plant nitrogen utilization rates are not high (17-45%). Even with large amounts of nitrogen applied, more than 50% of the total ammonia in rice yields was soil nitrogen. When the flooded paddy soil flooded, the reduction process was enhanced. The activities of the nitrifying bacteria were limited to the rhizosphere of rice and a thin layer of soil in contact with water. However, during the seedling stage of rice cultivation, oxidation and reduction processes inevitably occur in the soil, and nitrogen may be lost due to nitrification and denitrification.