Effects of Agricultural Cultivation on Different Organic Nitrogen Components in Black Soils of Northeast China
In order to clarify the influence of agricultural cultivation on soil organic nitrogen in black soil of Northeast China,soil samples(agricultural soil and undisturbed cemetery soil)were collected from north to south in black soil area,and the changes of total soil hydrolyzed nitrogen,hydrolyzed ammonium nitrogen,amino acid nitrogen,amino sugar nitrogen and unknown hydrolyzed nitrogen were determined by using Bremner method in this study.The results showed that agricultural cultivation significantly affected the content of the total soil hydrolyzed nitrogen in black soil area,with a variation range of 7.58%-30.43%.Moreover,the content of total soil hydrolyzed nitrogen was positively correlated with the geographical latitude and soil organic matter content significantly.Besides,compared with the undisturbed cemetery soil,agricultural cultivation significantly decreased the content of hydrolyzed ammonium nitrogen by more than 4.2%and changed the proportion of different organic nitrogen components in total soil hydrolyzed nitrogen.The content sequences of different organic nitrogen components in the cultivated soil were as follows:hydrolyzed ammonium nitrogen>amino sugar nitrogen>amino acid nitrogen>hydrolyzed unknown nitrogen.In addition,the organic nitrogen components were changed with latitude regularly in agricultural soil,especially the high content components of acid-hydrolyzed amino sugar nitrogen and hydrolyzed unknown nitrogen showed significant negative correlation and positive correlation with latitude,respectively.In general,agricultural cultivation significantly affected the content of total soil hydrolyzed nitrogen of black soil and changed distribution pattern of different organic nitrogen components.
black soil of northeast Chinasoil organic nitrogencultivation
万方数据
维普
