Study On Characters Of Phosphate Adsorption/Desorbs Of Suspended Sediments In The Three Gorges Reservoir Area

The Three Gorges engineering of the Yangtze River is the super water conservancy engineering and it spanned the century. When the engineering finished, The Three Gorges area will change from riverway to reservoir and the hydrology in three gorges will also change greatly, and it will lead the zoology and environment be change. Especially, parts of branches inclined to eutrophication because of low velocity of flow. In addition, the sandiness rate is high in the reservoir area because of the running away of the soil。This article points out that it is important to study sediments affects in the three gorges, analysis the effects of the adsorption/desorbs of suspended sediments to phosphate to eutrophication of the three gorges. There are several important aspects in the main study outcome:Firstly, the article summarizes the actuality of the study of adsorption/desorbs of the sediments and soil to phosphate. Points out there are many reports on the study of adsorption/desorbs of the sediments since 20th80s. and study the every factors to the desorbs and adsorption process, but it just about heavy metal and poisonous organic. The sorbents is localized in sediments of river and soil although we have deeply study about nutrient organic especially phosphate.Secondly, the article points out the change of desorb mass when the sediments diameter /concentration and phosphate concentration changed. The law of adsorption accords with fifth type Langmuir isotherm when sediments concentration is low (<1.0kg/m3), and it accords with Langmuir haploid molecule model. The phosphate adsorption on sediments will get to max when phosphate concentration increased when sediments concentration is low (<1.0kg/m3), afterward the phosphate adsorption mass will decrease when phosphate concentration keep on increasing. In addition, according with the desorbs experiments of sediments to phosphate , the desorbs of sediments to phosphate will decrease when sediments concentration and sediments diameter increase, and the time of desorbs balance of sediments to phosphate is more short.Thirdly, according to the studies on adsorption and desorbs of sediments of different position to phosphate, the influence of organic mass of suspended sediments on adsorption/desorbs is small. The PH of suspended sediments affects the adsorption/desorbs in a certain extent, the PH of suspended sediments is higher, the...