Contents And Chemical Forms Of Fluorine And Aluminum In The Soils Of Tea Garden Planning In Bijie Region

Fluorine and Aluminum in tea were harmful to human health, which was gradually attached importance to the researchers at home and abroad.The soils of tea garden planning areas in Bijie in Guizhou were studied in the paper.The pollution levels and situation characteristics of Fluorine and Aluminum in soils were researched by analyzing the chemical forms of Fluorine and Aluminum in soils in order to clarify geochemical status of Fluorine and Aluminum,and their transfer,delivery in soils. At the same time people can have preliminarily realized regular pattern which the tea leaves absorb and enrich Fluorine and Aluminum from the soil.Through studying the characteristics of transfer of Fluorine and Aluminum in soils,which can provide clues in order to know a special mechanism of enriching Fluorine and Aluminum,as well seek a breakthrough of prevention and treatment methods of tea-type Fluorine poisoning.Through this research,this thesis has been the following preliminary conclusions:1.The average value of pH was around 5.50 in soils investigated,these soils were significantly acidic.The standard deviation of pH value in soil sample was less than 1.0, the coefficient of variation was less than 20.0 percent.The pH value of the soils was in line with requirements of the tea plant leaves.The organic matter contents were different in study regional soils,and the highest value was 16.94 times of the minimum value.The difference of average of the exchangeable electropositive ions in the investigation regional counties soils were not significant,but it was a great difference between the maximum value and minimum value,their difference was about 75 times,so every county exchangeable electropositive ions of soils were of a great difference,the coefficient of variation was up to 95.74 percent.Which show greatly their difference of the exchange capacity of the soils.2.The average of Fluorine contents in three counties soils investigated was more than background value of soil.The maximum value of Fluorine was about 2.50 times of the background value in Nayong,and they were 1.94 and 1.75 times of the background value in Weining and Jinsa.The contents of Fluorine were great differences in three counties soils.The coefficients of variation were all more than 60 percent.The overall rates of exceeded standard value were 85.29 percent in three counties soils.3.According to study morphological characteristics of Fluorine in three counties soils,the distribution trend of forms of occurrence of Fluorine was residual fraction > organic phase> Fe-Mn oxides > water-solubility> exchangeable form.The contents of the high biologic validity water-solubility Fluorine and exchangeable form Fluorine were not high,the most were the form of residue Fluoride in soil,which showed harm of Fluoride in the studied soils reached the level of slightly ecological harm.4.The morphological characteristics of Fluorine were significant difference in different regions soils,the forms of Fluorine contents in soils were also impacted by different factors,which was the relationship with the composition of the soils,the structure of the soils,rock weathering as well as the development stutas of local industry and agriculture.But between different soils there were some common characteristics, namely:there were very significant positive correlations between the contents of exchangeable electropositive ions and pH values in soils in the 0.01 levels at a certain range(4.0～6.5), the average value of correlation coefficient was 0.766.There were the positive correlations between the contents of exchangeable Fluorine and exchangeable electropositive ions in soils.There were the significant positive correlation between iron-manganese oxide bound of Fluorine and organic bound of Fluorine.There were very significant correlations between organic-bound of Fluorine and residues of Fluorine with the total Fluorine in the 0.01 levels,the average values of correlation coefficients were 0.670 and 0.676.There were highly positive correlation between residual Fluorine and total Fluorine content in soil in the 0.01 levels,the correlation coefficient reached 0.999,that is,there was linear relationship between residual Fluorine content and total Fluorine content.5.The average of Aluminum content in three counties soils investigated was more than average of Aluminum in our country soils,the maximum value of Aluminum content in Nayong soil was about 2.0 times of the average of Aluminum in our country soils, they were 1.59 and 1.69 times of the average of Aluminum in our country soils in Weining and Jinsha.The contents of Aluminum were great differences in three counties soils investigated, their coefficients of variation(RSD) were all about 30.0 percent.If planting tea leaves in the high contents of soils, phenomenon of Aluminum poisoning must attach great importance to us.6.According to study morphological characteristics of Aluminum in three counties soils,the distribution trend of forms of occurrence of Aluminum was residual fraction > organic phase> Fe-Mn oxides > carbonates> exchangeable form.The most were the form of residue Aluminum in soil,The contents of the high biologic validity exchangeable form Aluminum and carbonates Aluminum were not high,which showed harm of Aluminum in the studied soils reached the level of slightly ecological harm.7.The morphological characteristics of Aluminum were significant difference in different regions soils,the form of Aluminum content in soil was also impacted by different factors, which were the relationship with the composition of the soil, the structure of the soil,rock weathering as well as the development of local industry and agriculture.There were some common characteristics between different soils,namely:there were very significant negative correlations between the contents of exchangeable Aluminum and pH values in soils in the 0.01 levels at a certain pH range(4.0～6.5),the average value of correlation coefficient was-0.693.There were the negative correlations between the content of exchangeable Aluminum and exchangeable electropositive ions in soil.There were highly positive correlations between residual Aluminum and total Aluminum contents in soils in the 0.01 levels,the correlation coefficient reached 0.964.8.According to analyzing correlation between contents of Fluorine and Aluminum in the soils,we can know that the correlation between Fluorine and Aluminum was not significant.9.By comparing the form of Aluminum and that of Fluorine in the three counties soils,we can know that the correlation was not significant between form of Aluminum and Fluorine.