| Black soil and its parent material are special sediments, and the study of its provenance characteristics is of great significance to the protection and utilization of black soil. In the north of Songnen Plain, the author selected Kedong County and other five counties with rich and deep black soil layer as the research area. Based on the geochemical data of the black soil layer and the parent material layer obtained from the ground substrate survey, the ground substrate types and geochemical elements characteristics of the black soil layer and the parent material layer were compared, and the provenance characteristics were discussed. The results show that loam is the main type of ground substrate in the black soil layer (92%), clay is the main type of ground substrate in the parent material layer (67%), followed by loam (24%). The average content of organic matter in the black soil layer (underlying non-sandy soil) is 3.34%, which is significantly higher than that in the parent material layer (non-sandy soil), which is 0.96%. The black soil layer (underlying non-sandy soil) has a good material inheritance to the parent material layer (non-sandy soil), but the black soil layer (underlying sandy soil) has no material inheritance to the parent material layer (sandy soil). Black soil and parent material (non-sandy soil) are aeolian origin, and Songnen Sandy land is the main provenance of the study area. During the formation process, the sediment has undergone a certain degree of recycling. The sandy soil under the black soil is obviously different from the black soil in geochemical characteristics, and the sandy soil should mainly come from the Lesser Khingan Mountains area. Therefore, it is of great significance to investigate and study the geochemical properties of the ground substate layer of the black soil for its material source area, formation and evolution history. |