Study On The Genesis And Utilization Of Selenium Rich Soil In Handan And Xingtai Area

Selenium is one of the essential trace elements in human life activities.Excessive or low intake of selenium will cause harm to human health.Handan and Xingtai region is an important grain producing area in Hebei Province,and the selenium content is relatively high.Therefore,it is of great significance to study the causes of soil selenium and its development and utilization in order to rationally develop and utilize selenium rich soil resources,protect human health,improve local economic level and promote the transformation of traditional agriculture.Through the collection and testing of multi-media,soil,groundwater,atmospheric dust and crop samples,the selenium content level in Handan and Xingtai region was analyzed and determined.The range of selenium rich soil was delineated by Arc GIS,and the formation reason of selenium rich soil was discussed.The migration and transformation law between soil and crops was deeply studied,and the ecological effect of soil selenium was preliminarily evaluated.Finally,the land in the study area was evaluated Based on the comprehensive evaluation of soil quality and the distribution of selenium,the development and utilization plan of selenium rich soil was put forward.The main conclusions are as follows1.The average Se content of surface soil in Handan and Xingtai area was 0.23 mg/kg,and the total Se content showed a decreasing trend from west to East.The average selenium content in the surface layer of the key anatomical area is 0.32 mg/kg.The high selenium value areas are concentrated in the north and middle of the study area.The selenium rich area is about 93.17km~2,and the selenium resources are relatively rich.The soil selenium content in Wuan section was higher than that in Baixiang section,which was only 0.18 mg/kg.2.The natural sources of soil selenium in the study area are mainly carbonate weathering and late Taiyuan Formation coal bearing strata,while the non-natural sources are coal burning,groundwater irrigation and chemical fertilizer.The main genesis of selenium rich soil is unnatural,and the enrichment of selenium in surface soil is caused by human activities.3.The migration ability of soil in the environment is closely related to the occurrence form.The results showed that selenium mainly migrated downward in water-soluble,exchangeable and carbonate combined forms in soil.The absorption and transportation capacity of different forms of selenium in different parts of wheat were different.The root of wheat was easy to enrich selenium,but it was difficult to transport the above ground part.Compared with wheat stem,wheat seed had stronger ability to transport selenium and its compounds.4.The average selenium content of wheat seeds was higher than that of other cereals,and the selenium enrichment rate of all crop samples was 63.63%.Selenium rich soil is an important basis for the production of selenium rich agricultural products.The existing forms of selenium and the absorption capacity of plants can affect the selenium content of crops.5.Most of the soil in the study area is not polluted by heavy metals,and the overall nutrients are relatively rich.The first and second grade soil quality can account for more than98%,and the comprehensive quality is high.The net increase of selenium content in soil is2.83?g/kg,and the selenium resources will not decrease significantly in a short period of time,so it has the sustainable development and utilization.6.The soil in the study area is divided into suitable areas for crop planting.The suitable planting areas can produce natural pollution-free selenium rich agricultural products.For other areas that do not meet the standard of selenium rich soil,combined with the local agricultural development situation,the corresponding planting measures are proposed to provide reference for the local agricultural development.