吉林西部盐碱水田生长期土壤有机碳和碱解氮的动态变化特征

aking Qianguo irrigation area of western Jilin Province as an example, the paper field collected saline-alkali soil and paddy soil of five different development years to build experimental plots. The paper tests the contents of soil organic carbon, carbonate and alkali-hydrolyzable nitrogen of seedling, tillering, tassel formation and fructicative stage with potassium dichromate oxidation external heating method, diffusion method and alkaline hydrolysis diffusion method, in order to analyze the seasonal dynamics and the characteristics of development years. The results show that organic carbon and alkali-hydrolyzable nitrogen exist obvious variations. The contents of organic carbon of surface soil increase in different degrees after a growth period, while the contents of alkali-hydrolyzable nitrogen decrease. The contents of organic carbon and alkali-hydrolyzable nitrogen have the same variation tendency during process of paddy development, they both increase with the increasing development years. This paper can provide data support for the study of seasonal cycle of soil carbon and nitrogen, offering scientific guidance to improve soil nutrition conditions and productivity of paddy field ecosystem, providing theoretical bases for land use and paddy field management in the study area.