研究稻田的氮素循环,包括肥料氮素与土壤氮素的矿化、固定、反硝化、淋溶以及植物吸收和生物固氮,对水稻稳产高产是十分重要的。作者在北陆农试站试验地用~(15)N进行了试验,同时用渗漏测定计做了实验。试验地为两种土壤:(1)强潜育化重粘土(半不良排水田),(2)潜育化重粘土(良排水田)。渗 Studying the nitrogen cycle in paddy fields, including the mineralization of nitrogen and soil fertilizers, the fixation, denitrification, leaching and the absorption of plants and biological nitrogen fixation, is very important for the stable and high yield of rice. The author experimented with ~ (15) N at the pilot station of Hokuriku, and did the experiment with the leak tester. Two types of soils were tested: (1) heavily glenified heavy clay (semi-poorly drained fields), (2) gleyed heavy clay (well drained fields). Infiltration