The Impact Of Arsenic Contamination Of Soil And Crop Systems

Arsenic is a toxic metalloid, has a carcinogenic effect on human and other organisms. In recent years, endemic arsenic contamination has become a prominent environmental issue. Arsenic accumulation in environment will inevitably affect the quality of water and soil, the normal growth and development of crop. The crop quality, antioxidant enzyme system can indicate pollution status of crops, so the corn quality, the determination of antioxidant enzymes is an important indicator of serious pollution or not.This experiment was aimed to reduce the processing costs and time, improve treatment effect with the new adsorbentIn this thesis, the research conclusions are as follows:1. the relative relationship between Arsenic residue in crops and arsenic levels in soil in different areasIn this study, there are four typical areas (Beijing, Anhui, Shuozhou, Ying County) as the main study areas. Determination of Arsenic content in crops and soil which from the four areas by atomic fluorescence spectrometrcrop, analysis of relationship between arsenic residues in crops and arsenic content in soil. The results showed that arsenic levels in soil are much larger than in crop, and arsenic accumulation in different varieties of crops is different.2. The effect of Arsenic at different concentrations on corn seed germination rate, seedling height and root lengthLaboratory incubation methods, with different concentrations of arsenic treatment series(0,0.1,0.5,1,2mg·L-1), were tested on maize seed processing, testing seed germination rate of maize and measuring seedling height and root length. The test results showed that low content of Arsenic could promote the germination rate of corn seedlings, seedling height and root length; high content of Arsenic could inhibit that.3. The effect of Arsenic at different concentrations on the quality of maize seedlingsBased on the above test, colorimetric was used to measure maize seedlings chlorophyll, protein and soluble sugar content. The results showed that low concentration promotion and high concentration inhibition on the content of chlorophyll, protein, soluble sugar。4. The effect of Arsenic at different concentrations on the antioxidant enzyme system activity in corn seedlingsBased on the previous test, select the size of maize seedlings, colorimetry and titration were used to measure maize seedlings polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), β-1,3dextrancarbohydrases (β-1,3glucanase) and catalase (CAT) activity. The results showed that PPO, PAL and CAT activities were promoted in the low concentration and were inhibited in the high concentration, while β-1,3glutamate activity had no significant change in different concentrations of Arsenic series.5. Arsenic enrichment in different parts of cornAccording to the above experiment, atomic fluorescence spectrometry was used to measure Arsenic content in root and leaves of maize seedlings. The test results showed that Arsenic content in root was significantly greater than in leaves.6. Studies on optimal adsorption condition of new adsorbentAdding different amounts of adsorbent in50ml arsenic concentration of1mg·L-1solution to research the adsorption effect of adsorbent dosage on Arsenic-containing solution; after optimum adsorption dosage was determined, Arsenic-containing solution were adsorbed by new adsorbent with different time so that could determine the best adsorption time; finally, the adsorption experiments at under different pH conditions to determine optimal pH. The results showed that optimal adsorption condition is4g of new adsorbent at pH8with adsorption time of15min, the best adsorption efficiency reaches97%.