Analysis And Evaluation Of Heavy Metal Contents Of Common Fertilizers Used In Typical Northern Vegetable Fields

With the improvement of human living standards,people's attention to food safety has been increasingly strengthened.Food safety is closely linked to each person's living standards and quality of life.There are many reasons why food is problematic,and soil heavy metal pollution is even more prominent.The heavy metals in soil mainly come from fertilizers,sewage use,solid wastes and atmospheric deposition.The application of fertilizers containing too heavy metal elements to the soil is one of the reasons why soil heavy metals are excessively important.Fertilizers provide sufficient nutrients for plant growth.Fertilizers can increase the yield of crops and the quality of crops.One of the most useful ways to increase food production and character,whether in developed or developing countries,is to apply fertilizers to crops.In recent years,the state has paid more and more attention to the agricultural economy and hopes to revitalize the rural economy.At this t ime,people will pursue large-scale application of fertilizers to increase production,but the raw materials for organic manure production are livestock manure,solid waste,sludge,Industrial and agricultural wastes and other harmful heavy metals,not only the production of raw materials in the organic fertilizer production process there are also harmful heavy metal residues,making heavy metals follow the application of fertilizer into the farmland,thus easily causing environmental pollution,a large probability leading to farmland and crops Excessive levels of heavy metals,even through the food chain,pose a risk to human health.Fertilizers and crops are interdependent,the dependence of crop growth on fertilizers is enhanced,and fertilizers play an important role in the increase of crop yields.It is of positive significance to understand the heavy metal content of chemical fertilizers,enable safe application of fertilizers,and maximize the control of heavy metals entering farmland soils.In particular,it is more meaningful to analyze the heavy metal content of the fertilizer used in the northern vegetable field base area.It is based on the concern of this issue that this paper mainly carried out the following research.Including collection of literature data,sampling of commercially available fertilizers from northern vegetable fields(Shouguang C ity,C hina),analysis of five heavy metal contents of arsenic,chromium,cadmium,lead,and mercury in fertilizers and environmental risk assessment.The main results are as follows:1.All of the fertilizer samples collected in this experiment contained arsenic,lead,cadmium,chromium,mercury,and other harmful elements.The content of heavy metals in organic fertilizers is higher than that of other fertilizers;the average content of cadmium and lead in microbial fertilizers is the highest;the average content of chromium in biological organic fertilizers and phosphorus fertilizers is high,but not excessive;urea,phosphate fertilizer and potash fertilizer The average content of heavy metals in fertilizers is relatively low and does not exceed the standard.2.The analysis results of the heavy metal single factor pollution index and the comprehensive pollution index show that: Therefore,the risk of heavy metal pollution in organic fertilizers and bio-organic fertilizers is the greatest.Although the single-factor pollution index is less than 1,the heavy metals have cumulative risks and deserve our attention.In the other fertilizers,the single factor pollution index of all heavy metals was also less than 1,and all of arsenic,lead,cadmium,chromium,and mercury were all clean.The comprehensive pollution index of arsenic,lead,cadmium,chromium,and mercury is between 0.14 and 0.61,all of which are safety grades.3.Heavy metals in fertilizers pose a risk to the soil environment.Based on the first grade standard of soil environmental quality in C hina as the evaluation standard value,Lead and mercury in organic fertilizers and bio-organic fertilizers have the highest levels of soil contamination,with the lead pollution level at the alert level and mercury pollution at light pollution levels.The cadmium single factor pollution index in microbial fertilizers is 9.0.If applied to the soil,the impact on the soil is heavy pollution and reaches a serious level of pollution.Chromium in phosphate fertilizers has a relatively high degree of soil contamination,with a one-factor comprehensive pollution index value of 0.25.The arsenic single factor pollution index values in all fertilizers were all less than 1,indicating that the arsenic in the fertilizers would cause less pollution to the farmland soil after they were put into the farmland,and all were clean.