Geochemical Characteristics Of Selenium And Other Elements In Soil And Agricultural Products In Typical Areas Of Shandong Province

Through the agricultural geological survey over the typical area in Shandong Zhangqiu, Laiwu, Zaozhuang, Huantai and Qingdao, we collected samples in the soil, specialty crops and agricultural products and analyzed geochemical characteristics of selenium and other elements. Selenium status of soil and crops were evaluated in the study area combining with the specifications and standards of “ the land quality geochemical assessment standard”. The selenium-rich soil with sufficient nutrition elements and standarded heavy metals which was circled in Zhangqiu and Laiwu are all of high quality, having high selenium-rich soil and selenium-rich agricultural products development value. Some initial suggestions are also given on the planting of selenium-rich crop cultivation, the safety of agricultural products and reasonable fertilization. The main results obtained are as follows:1) Most of the surface soil in the study area are at the level of enough selenium(about 75%) and rich selenium(about 20%).The circled selenium-rich soil area in Zhangqiu is about 63 kilometers; while the area in Laiwu was about 54 square kilometers.2) The content of Se in soil has a significant positive correlation with the content of organic matter. While effective Se content has a significant positive correlation with Se content, and the Se content is higher at areas with higher pH, meanwhile the effective Se mainly occurs in the silt soil.3) The content level of nutrition element in the surface at the studied area is above moderate, while the content of P element achieves a very level. The soil pollution index of heavy metal element at the research area is mainly less than 0.7, and the soil environment is clean, while individual soil pollution index of Cd is between 0.7 to 1 with the soil environment level as slight clean. The comprehensive soil geochemical comprehensive quality level at the studied regional is of high quality.4) In addition to Zaozhuang, the wheat and corn in the other parts has reached the selenium-rich standard at different proportion. Meanwhile six kinds of crops reaches the requirements of the rich selenium standard.5) Corn, wheat, cabbage and tea samples are in the standard range of heavy metals. As and Hg did not excess standard in all agricultural products, only one cole sample exceeded the standard of Cd, and the samples exceeding the standard of Cr and Pb are relatively larger.Therefore, the safety of agricultural products should arouse the attention of the relevant departments.