Spatial And Temporal Distribution Characteristics Of Soil Carbon And Nitrogen In Typical Farmland Black Soil In Suihua City

For revealing the evolution characteristics of carbon and nitrogen in typical black soil soil in Suihua city on time and space scale,this study systematically studied the spatial and temporal distribution characteristics of organic carbon and total nitrogen in typical black soil soil in 8 counties(cities,districts)of Suihua city in 2002 and 2019 using geostatistics and Arc GIS software.The main research results are as follows:(1)The organic carbon content of black soil in Suihua was 10.66 ? 35.85 g/kg in2002.Average 22.02 g/kg.Total nitrogen content 1.33 ? 3.31 g/kg.Average content 2.16g/kg.According to the national grading standard of soil secondary nutrient content,organic carbon medium level,full nitrogen rich level;organic carbon and all nitrogen are medium variation levels.(2)The organic carbon content of black soil in Suihua was 11.48 ? 36.39 g/kg in2019.Average 21.67 g/kg.Total nitrogen content 1.12 ? 4.62 g/kg.Average content 2.04g/kg.According to the national grading standard of soil secondary nutrient content,organic carbon medium level,full nitrogen rich level;organic carbon and all nitrogen are medium variation levels.(3)Between 2002 and 2019,the average content of organic carbon and total nitrogen in black soil of typical farmland in Suihua city showed a decreasing trend,the average organic carbon content decreased by 1.6 %,the average nitrogen content decreased by 5.6 %,the organic carbon coefficient of variation decreased by 1 %,the coefficient of variation of total nitrogen content increased by 8 %.In terms of spatial distribution,the change of organic carbon content in Wangkui County is the largest,up14.97 percent,the change of average organic carbon content in the northern forest area was minimal,up 0.7 %,changes in other counties and cities ranged between 2.2 ? 9.8 %.The change of total nitrogen content in Lanxi County is the largest 20.57 %.The mean change of total nitrogen content in Helen is the smallest,up 0.86 %.Changes in other counties and cities between 0.92 ? 13.96 %.