| The article is chosen according to technology development projects in Jilin Province:The long term study of the lake sediment fluoride released mechanism in west of Jilin Province, and carried on a special investigation for the high concentrations fluoride lake sediments fluoride migration rule, transportation mechanism, forms analysis and influence factors in West of Jilin Province. The low plain area in Western Jilin Province is a model area of high fluorine concentration and fluorosis area. The climate in the area was the arid and semiarid.The area was the shortage of lakes which was alkaline water mostly. The lakes and mud were heavily contaminated by fluorine. Therefore,there was some practical meaning to solve the situation of water resource shortage and accelerate the development of ecological environment in west of LiJin Province.The paper was focused on the lakes:Chaganpao lake, Yueliangpao lake, Huaaopao lake, Daozipao lake and Dabusupao lake, which were the main lakes located in the low plain area in west of Jilin Province.We used the way of field survey and the lab experiment to analyse the lake water and sediment Physicochemical properties and the water type hydrochemistry. The results indicated that the type hydrochemistry of lakes water were:HCO3-Na type,HCO3-Na·Ca type,Cl-Na type,Cl-Na type andCl·CO3-Na type in order, respectively. High concentrations fluoride, strong alkalinity and high salinity were the chief features of the water. The lake mud was the gray fine sand and clay primarily after drying. Alkaline and rich in iron, aluminum and organic matter were the characteristics of sediment. From the research on the sediment fluoride migration behavior in the soil-water entironment we can found, the concentration gradient was the driving force in lake sediment natural release process.The release quantity was the biggest in the first six days and the process basically completed within the 22 days or so. The maximum release quantity was the Dabusupao lake sediment.Come next there were Huaaopao lake, Dazipao lake, Chagan lake and Yueliangpao lake in sequence. The day average release quantity of Dabusupao lake sediment was 5.58～17.61mg/kg, and total release quantity was 150.85～475.61mg/kg in 27 days. The day average release quantity of Yueliangpao lake sediment was 0.16～0.26mg/kg mg/kg, accumulative total release quantity was 4.34～7.02mg/kg in 27 days. With the release experiment went on, plus NaF continued injected. Fluorine in Solid phase reduced constantly. Contrarily, fluorine increased constantly in liquid, and fluorine in liquid started to transfer into solid phase.The sediment began to adsorb fluorine. The adsorption experiment result shown that, adsorption effect of sediment to fluoride was mainly concentrated in 4～6 days. The Dazipao lake sediment average adsorption quantity was the largest, the total adsorbent was 42.37～45.96mg/kg, average adsorbent was 4.71～5.11mg/kg.The minimum sediment average adsorption quantity was Chagan lake, the accumulation adsorbent was 35.4～44.28mg/kg mg/kg, average adsorbent was 3.93～4.89mg/kg. In addition, the adsorption isotherms curve was similar to the Langmuir in the acidic conditions. The mode of adsorption was L type; the adsorption isotherms curve is similar to the Freundlish in alkaline conditions, the mode of adsorption was F type.Form the experiment of influential factors of sediment fluorine released process analyzing we knew, the effect of PH value on sediment fluorine release process was the most important. When the pH value≥5, the release quantity and sediment fluorine pH value were correlated positively. Under strong acidic water the quantity of fluorine release will be a slight increase compared with the weak acidic water. We can concluded that the rate of fluorine releasing in the sediment under the alkaline water was faster than it under acidic water. The rate of fluorine releasing was generally less than 2%d-1 under alkaline water; The rate of fluorine releasing was 15.22～35.88%d-1 under acidic water. High temperature condition can conduce that sediment fluorinated minerals solubility increased and ion active strengthening which resulted the release of sediment fluorine. Water power condition can do a certain extent influence on the sediment fluorine migration behavior to water and the diffusion speed into the water. The fluorine release quantity was increased in a situation of water disturbance, then the release quantity could reduced when the first day after water power stop. With the stop time extended, the release quantity will slowly increasing. Under the environment of high Na/Ca rate, the fluorine mineral solubility reduced,so the fluorine could formed new precipitate which due to the rate went against the sediment fluorine released.On the study of fluorine existing status in the lake mud in the west of Jilin Province, we through the experimental of sequential filtering extraction, picked up the sediment fluorine step by step in natural state and in different pH level, it shown that:residual fluorine>>water-soluble fluorine>organic fluorine>iron-manganese combined fluorine>exchange fluorine. Except the content of the Fe/Mn-F closed to the Or-F, other forms of fluorine distributed as the logarithmic-level basiclly. As we knew, the organic matter content, clay grain percentage, pH value and content of iron and aluminium were the significant influencing factors on forms of fluorine distributed in the lake mud, and the effect of pH value was the most observably. The change trend of Ws-F and Ex-F were similar. The released amount had a positive correlation with the pH. Contrarily, Or-F and Fe/Mn-F were both had a negative correlation with the pH. The discussion of the behavior of fluorine migration in the soil and water environment indicated:the Ex-F, Fe/Mn-F, Or-F and Re-F would converted into the Ws-F under the alkaline environment.The fluoride was migrated and transformed through a range of physiochemical reaction processes such as mechanical screening, adsorption-desorption reaction, precipitation-solution reaction, and complexation-dissociation reaction in water-soil environment of in the west of Jilin Province. The ferric and aluminum oxides were the main adsorbent for F in the water-soil environment. CaF2,CaCO3 and Carbonic acid balance were the key controlling element of precipitation-solution reaction.pH value through worked upon the forms of Fe3+,Al3+ to control the aspect and stability of the complexation-dissociation reaction.
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