关键词: 抑制剂, 脲酶, 硝酸还原酶, 亚硝酸还原酶, 羟胺还原酶, 活性

Abstract: Paddy soils account for 60% of the total cultivated areas in Jiangsu province and their rice yields account for 75% of the total grain output. In this province, paddy soils are classified into five types:permeable, stagpating, percolating, waterlogged and side-bleaching, which differ in their distribution and fertility features. The level of soil fertility has been significantly promoted by a series of effective measures such as building irrigation works, applying fertilizers and manures and practising rotation cropping systems. But different obstacle factors still exist. In this paper, factorial and discriminatory analyses are used to establish a model for discriminating the fertility classes of the paddy soil. To make full play of the productive potentials of paddy soils, it is needed to further improve the ecological environments of farmland, apply fertilizers rationally and adopt better cropping systems.