不同施肥方式下水稻土氮形态及有机氮有效性

Soil Nitrogen Forms and Availability in Paddy Soil under Different Fertilization Ways

为了揭示长期不同施肥方式对水稻土氮素分布情况的影响,在延边地区水稻田选取7个典型地块,分0-10 cm和10-20 cm采集土壤样品,测定了土壤有效氮、全氮、无机氮及有机氮各组分含量。结果表明：土壤氮素随层次的增加呈减少的趋势;不同施肥方式对0-10 cm水解氮、全氮、有机氮含量有显著或以上水平影响。施肥方式对10-20 cm土层中全氮含量有显著性影响。有机、无机肥配施有利于土壤有效氮的积累。施有机肥有利于全氮、有机氮的积累;土壤氮素以有机氮为主;就通径分析的直接效应而言,氨基糖态氮、酸解未知氮、非酸解氮对有效氮的影响较为显著,氨基酸态氮与有效氮呈很小负相关。氨基酸态氮是通过其他组分间接影响有效氮。就通径分析总体效应而言,非酸解氮对有效氮影响最大。促进非酸解氮、酸解未知氮的转化,增加有效氮积累是合理施肥要考虑的重要因素。

In order to reveal characteristics of soil organic nitrogen components under different long-term fertilization methods on paddy field,7 typical paddy fields of Yanbian Korean Autonomous Prefecture of Jilin Province were selected,soil samples of from 0 cm to 10 cm and from 10 cm to 20 cm were collected,and available nitrogen,total nitrogen,inorganic nitrogen content and each component of organic nitrogen were analyzed. Results showed that soil nitrogen decreased with the increase of soil depth. Different fertilization methods had a significant or greater effect on available nitrogen,total nitrogen and organic nitrogen in 0 cm to 10 cm soil,and it had a significant effect on total nitrogen content in 10 cm to 20 cm soil. Combined applications of organic and inorganic fertilizer was beneficial for improving available soil nitrogen. Applying organic fertilizer was beneficial for accumulation of total nitrogen and organic nitrogen. Organic nitrogen was a major part of soil nitrogen. In terms of directly affection of path analysis,effects of ammonia sugar nitrogen,acid-hydrolysable unknown nitrogen and non-hydrolysable nitrogen on available nitrogen were significant. A small negative correlation was shown between amino acid nitrogen and available nitrogen. Amino acid nitrogen indirectly affected available nitrogen by other components. In terms of general effect of path analysis,influence of non-hydrolysable nitrogen on available nitrogen was the largest. An important factor to be considered in relation to reasonable fertilization is that promoting non-hydrolysable nitrogen and acid-hydrolysable unknown nitrogen transformed into available nitrogen and accumulated available nitrogen.