Spatiotemporal changes of soil organic matter in the Songnen and Sanjiang plains of Heilongjiang Province over 40 years
The spatiotemporal changes in soil organic matter(SOM)hold great significance forthe elevation of both regional soilquality and the potential of soil carbon sequestration.Based on two periods of soil data from the second soil reconnaissance surveyof Hei-longjiang Province in 1980 and thesoil geochemical survey of Heilongjiang Province in 2020,this study analyzed the spatiotemporal changes in SOM content in surface soil(0～20 cm)in the Songnen and Sanjiang plains in Heilongjiang Province over 40 years through spatial analysis in GIS.Furthermore,this study summarized the distribution patterns of SOM lossof different soil types in various cities and counties.The results indicate that the average SOM content in the surface soil in the major two plains decreased by 5.68x10-3over 40 years,generallyexhibiting a downward trend.Areas with decreased SOM are primarily distributed in Qiqihar,Daqing,western Suihua of the Songnen Plain,along with Hegang and western Jiamusi of the Sanjiang Plain,with the largest decreased amplitudeob-served in the Qiqihar Zhaoyuan area along the Nenjiang River basin.Regarding soil types,swampsoils exhibited the highestSOM loss rate(-44.68％),while grassland soilsexhibited a contribution rate for SOM of 44.14％,which established these soilsas the soil type making the most significant contribution to SOM in both plains.The SOM loss area in Wangkui County,Zhaoyuan County,and Daqing City accounted for over 72.11％of the total.This study determines the spatiotemporal changes in SOM in the major two basins in Hei-longjiang Province on a scale of 40 years,providing a theoretical basis for the primary prevention and control targets of regional black soil degradation.
soil organic matterspatiotemporal changerulelosstwo major plains
国家科技期刊平台
NSTL
万方数据
