[Characteristics and Causes of Ge Enrichment in Vegetable Growing Areas of Beixintun Town, Zhangjiakou City].

The vegetable planting base in the Beixintun area of Zhangjiakou City was selected as the study area, divided into the focus area and regional range as well as the upstream area. A total of 132 surface soil samples, 16 vertical soil profiles, 3 groups of surface profiles, and 4 samples each of colored pepper fruit, purple kale fruit, and corn fruit were collected. From the soil, rock, and crop sample Sc, Cr, Mo, Cd, V, Zn, Sr, Pb, Co Ni, Cu, Ge, and REE on the basis of the referenced germanium (Ge) enrichment standards and enrichment factor levels, it was found that the regional Ge enrichment rate was not high (19.7%), whereas the key area had a high Ge enrichment rate (52%). The spatial distribution of Ge and rare earth elements in the soils of the regional scope and the focal area showed a more obvious consistency, and further comparison of the correlation characteristics of Ge and rare earth elements in soil and crops showed that the ranking of rare earth content was purple kale>colored pepper>maize, whereas the ranking of the Ge element uptake intensity was maize (weak uptake)>purple kale (very weak uptake)>colored pepper (very weak uptake), and there was no obvious synergy between the uptake of Ge and rare earth elements by crops. The PMF and RDA analysis of 28 elements and indicators of soil in the study area showed that the source of regional Ge was dominated by natural geological background factors (66.3%), supplemented by anthropogenic activity-influenced factors (27%) and river deposition factors (6.7%). The source of Ge in the focal area was dominated by natural geological background factors (33.8%) and anthropogenic activity-influenced factors (27.2%), with river sedimentation factors (18.5%) and atmospheric dry and wet deposition factors Ge (20.5%) being supplemented. Soil Ge was positively correlated with rare earth elements and trace elements such as Cd, Zn, Mn, Ni, V, Co, and Cr and negatively correlated with the main elements ČNa ₂ [KG-*2/5]O, SiO ₂ , and K ₂ [KG-*2/5]O and pH. Finally, by combining the analysis of soil lateral profiles with vertical profiles, it was found that the Ge migrating from the source area to the area was primarily in the main river pathway, supplemented by the secondary river and flood flow pathways.