Long-term Rotation Fertilization Effects On Soil Organic Nitrogen Components

According to the organic nitrogen in the soil after acidolysis differ in shape, soil organic nitrogen can be divided into ANOH(Acid hydrolysable orgsnic N) and NHN(Non-hydrolysable N) two parts, the AHOH including AN(Ammonia N),AAN(Amino Acid N),ASN(Amino sugar N),HUN(Hydrolysable unidentified N).Organic nitrogen as the main source of soil nitrogen supply nutrient, and crop nitrogen library source of minerals and nutrients needed. The composition and content of organic nitrogen in the soil and the mineralization conditions and related law is closely related to soil nitrogen supply ability, for the nitrogen cycle, soil fertility level and agricultural ecological environment has important influence. In recent years, domestic and foreign existing related researchers and scholars in long-term experiments as the research object, studies the content of organic nitrogen components under different indicators of components and their ratio change rule, but the results are not consistent, and at present for long-term rotation under different fertilizer treatments on organic nitrogen composition and proportion of research is rarely reported.This experiment in Shenyang Agricultural University topped the long-term rotation positioning fertilizer brown soil testing as the research object, soybeans and corn crop rotation was studied under different fertilizer treatments on soil organic nitrogen and microbial biomass nitrogen, a better understanding of soil organic nitrogen in the relevant laws and profound understanding of the understanding of soil for nitrogen potential, so as to better to develop a rational fertilization methods, to improve crop quality and yield and improve the quality of soil nutrients play a better role in guiding. The main results were as follows:(1) Long-term rotation fertilization can enhance arable layer soil organic nitrogen content of components. Although slightly different in the different fertilizer treatments, since the childhood is the basic order of:ANS< HUN< AN< NHN<AAN. Arable layer soil organic nitrogen content and composition is affected by the fertilization of chemical fertilizer treatment, organic fertilizer and inorganic fertilizer, especially the high amount of organic fertilizer and fertilizer NPK, can significantly improve arable layer soil organic nitrogen the absolute and relative content of each component, especially for the ascension of amino acid nitrogen effect is most obvious.(2) Long-term rotation fertilizing soil organic nitrogen components can acid solution under the profile distribution of broadly similar, with soil depth deepening all components in lower:nitrogen is not only the acid solution to meet the trend, reflecting the disorder. Basic law embodied in the groups:no fertilizer treatment and single fertilizer< single organic fertilizer processing< organic inorganic fertilizer treatment.(3) Long-term rotation fertilization can enhance arable layer soil microbial biomass nitrogen content. This trend is shown as:CK< fertilizer area< low levels of organic fertilizer area< high amount of organic fertilizer, soil microbial biomass nitrogen content especially under the effect of organic inorganic NPK promoted effect is most obvious.All components of soil microbial biomass nitrogen and organic nitrogen showed positive correlation and extremely significant, especially amino sugar nitrogen on soil microbial biomass nitrogen contributions the most significant role.