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用Bremner法测定东北地区滨海盐渍土型开垦5年、30年稻田土壤和邻近未开垦稻田的旱地土壤的有机氮各组分含量。结果表明:(1)在0~60 cm土层,3种土壤非酸解性全氮含量及其占全氮比率明显大于酸解性全氮,但总体上以表层土壤(0~20 cm)为最高。(2)与未开垦旱地土壤相比,种稻5年和30年均使表层土壤酸解全氮含量明显下降,但种稻5年使土壤酸解氨基酸态氮和氨基糖态氮的含量及其占全氮比率明显增加,使氨态氮和未知态氮的含量及其占全氮比率明显下降;而种稻30年则均使土壤酸解各组分氮含量及其占全氮比率明显下降。(3)与未开垦旱地土壤相比,种稻5年和30年稻田土壤酸解全氮含量及其占全氮比率均随土层深度的增加而逐渐降低,但2种稻田土壤酸解各组分氮含量及其占全氮比率的剖面分布则无明显的变化规律。
Bremner method was used to determine the contents of organic nitrogen in the coastal saline soil of northeast China for 5 years and 30 years of paddy soil and the dry land of adjacent uncultivated paddy fields. The results showed that: (1) At 0 ~ 60 cm soil layer, the content of total non-acid soil total nitrogen and the percentage of total nitrogen in soil were significantly higher than that of acid soil total nitrogen, but the surface soil (0-20 cm) was the highest. (2) The total acidolysis of surface soils significantly decreased after 5 and 30 years of paddy cultivation compared with the non-reclaimed paddy soil. However, the contents of acid and amino-sugar nitrogen and amino sugar nitrogen in soil after five years of paddy cultivation and The ratio of total nitrogen to total nitrogen was significantly increased, the content of ammonia nitrogen and unknown nitrogen and the percentage of total nitrogen decreased obviously, but the content of nitrogen and the percentage of total nitrogen decline. (3) Compared with uncultivated land, soil total acid-hydrolyzable total nitrogen content and total nitrogen ratio of paddy soil decreased gradually with the depth of soil layer increasing, but the contents of acidolysis There is no obvious change rule for the distribution of nitrogen content and total nitrogen ratio.