关键词: 地质高背景, 水稻, 镉, 耕地, 安全生产阈值

Abstract: It is inconsistent to exceed the Cd standard in the high geological background area and the Cd standard in the rice area, so the safe production threshold of rice-cadmium cultivated land suitable for the high geological background area should be selected.This study based on the soil heavy metals-rice, physical and chemical means of correlation analysis, through spatial interpolation and parameter calculation, get the following results,Cd content in soil and soil physical and chemical indicators (pH, organic matter, cation exchange capacity) is weak, the linear relationship between the regions with high explain geological background due to factors such as soil background value, the soil pollution is serious.There is a close relationship between Cd in rice and soil physicochemical properties, which may be because although the background value of heavy metals in high geological background is high, it is not affected by human activities and has little impact on Cd content of rice planted.By calculating the required parameters and interpolation, the cultivated land safety threshold of the geological high background area was preliminarily judged to be 0.31 mg/kg. The reasonableness of the predicted results was tested, and the result showed that the cultivated land security threshold in the geological high background area was set reasonably.

Key words: high geological background, rice, cadmium, cultivated land, safety production threshold