Study On Soil Nutrient Factor And Selenium Enrichment Of Vegetables In Ledou Selenium-rich Region

The range of selenium enrichment region in Qutan town, Ledou country,Qinghai province was delineated by geological findings.65topsoil samples and157vegetables were collected, The total selenium content, nutrient factor of soil samplesand total selenium content, part of nutritional quality of vegetables samples wereanalysised. The effect of nutrient factor of soil to total selenium content, differentenrichment and nutritional quality of vegetables were researched. The types ofvegetables and soil selenium enrichment level were evaluated by divided ecologicallandscape selenium limit value. The results were shown as below:(1) The total selenium content of Ledou topsoil in the range of86~608μg/kg, theaverage of total selenium content of Ledou topsoil was257μg/kg. Hongzhuangvillage, where the highest selenium content of soil in Ledou, it was reached468μg/kg,86.1%of soil samples was enough selenium,7.7%of soil samples was Se-rich. Thetotal selenium content in topsoil and available phosphorus and potassium had asignificant relationship.(2) Selenium content in vegetables were different between the species. The averagelevels of selenium from high to low were: garlic, jerusalem artichoke, french bean,cabbage, radish, carrot, garden beet, potato, pepper. The vegetables reached Se-richlevel as follows: garlic (90.0%), Jerusalem artichoke (66.7%), radish (87.5%), carrot(78.1%), garden beet (61.9%), potato (65.0%),french bean (81.8%), pepper (40.0%),cabbage (60.0%).(3) Most of selenium in vegetables was organic selenium. The garlic organicselenium reached156.84μg/kg, was the highest of the vegetables. The pepper organicselenium reached53.53μg/kg, was the lowest of the vegetables. Jerusalem artichokehad highest conversion rate, potato had the lowest conversion rate respectively was85.76%and74.89%. The different vegetables had different enrichment capability,follow: garlic, french bean,radish, cabbage, carrot, Jerusalem artichoke, garden beet,potato, pepper. (4) The correlation of different selenium content and nutritional quality indifferent vegetables was not same, Vc and selenium content in garlic at0.05levelwas negatively correlated. The selenium content and Ca, P in carrot at the0.01levelwere significantly and positively correction. It was related to the selenium and Vccontent of potato, and Ca, Mg content in0.01level was positively correlated. The Ca,Mg content in garden beet positively correlated at the0.01level with seleniumcontent. There was no obvious correlation between the Se content and nutritionalfactors of others vegetables. There was linear relation between4total seleniumcontent of vegetables(garlic, jerusalem artichoke, radish, potato) and soil totalselenium content.