棕壤各亚类碱解氮含量由高到低依次为：白浆化棕壤>典型棕壤>棕壤性土>潮

The content of alkali-decomposed nitrogen in each subtype of brown soil from high to low is as follows: white pulped brown soil>typical brown soil>brown loamy soil>tidal brown soil. The content of alkali-decomposed nitrogen in subgroups of the Chao soil is quite different. The total nitrogen of Chao soil is the highest, with an average content of 71.13mg/kg; the salinized Chao soil is the lowest, with an average of 61.24mg/kg. The highest value of alkali-decomposed nitrogen was 213.4 mg/kg, which appeared in the subgroup of Chao soil. The content of alkali-decomposed nitrogen in Chao soil is higher than that in salinized Chao soil. <br>(2) The content of soil alkaline nitrogen in different types of land. The average content of soil alkaline nitrogen in different types of land varies greatly, among which the vegetable field has the highest content, with an average of 72.87mg/kg, and a variation range of 40.0~114mg/kg; Grain field, the average content is 70.16mg/kg, the variation range is 21~213.4mg/kg; the orchard is the lowest, the average is 64.63mg/kg, the variation range is 23.5~134.0mg/kg.

The sub-alkali denitrogen content of brown soil is from high to low in order: white-pulpized brown soil, typical brown soil, brown soil, tide brown soil. The content of sub-alkali denitrogen solution in the tide soil was different, the tide soil was the highest, with an average content of 71.13 mg/kg, and the salted soil content was the lowest, with an average of 61.24 mg/kg. The highest value of alkali denitrogen is 213.4 mg/kg, which appears in the tidal sub-species. The nitrogen content of tidal soil alkali is higher than that of salinized tide soil.<br>(2) Soil alkali nitrogen content of different land types. The average content of soil alkali nitrogen relief between different land types is different, of which the vegetable land content is the highest, with an average of 72.87 mg/kg, with a variation of 40.0 to 114 mg/kg; Field, average content of 70.16mg/kg, change rate of 21 to 213.4mg/kg, lowest orchard, average 64.63mg/kg, change 23.5 to 134.0mg/kg

The order of alkali hydrolyzable nitrogen content in brown soil was albic brown soil > typical brown soil > brown soil > tidal brown soil. The content of total nitrogen in fluvo aquic soil was the highest with an average content of 71.13mg/kg, while that of saline soil was the lowest, with an average of 61.24mg/kg. The highest value of alkali hydrolyzable nitrogen was 213.4mg/kg, which appeared in fluvo aquic soil. The content of available nitrogen in fluvo aquic soil was higher than that in saline soil.<br>(2) The results showed that the average content of soil alkali hydrolyzable nitrogen was significantly different among different land use types, among which vegetable field had the highest content, with an average of 72.87mg/kg, with a range of 40.0-114mg/kg; the second was grain field, with an average content of 70.16mg/kg, with a range of 21-213.4mg/kg; orchard was the lowest, with an average of 64.63mg/kg, with a range of 23.5-134.0mg/kg<br>