Poyang Lake Typical Wet Metro Distribution And On Soil Phosphorus Adsorption And Release Effect

Iron as the typical redox sensitive elements, in the wetland soil redox reaction cycle plays an indispensable role.Active iron content, marking the wetland soil redox properties, affecting the wetland soil around other nutrient elements in plants enrichment.This study used the site test and laboratory simulation combining typical to Poyang Lake subway, wet distribution and on soil phosphorus adsorption and release effects were studied.The results show that:1. Moist Poyang Lake subway morphology in different profiles have differences, but with the soil depth, iron by high valence state into low state, soil by the oxidation state is reducible, soil is the reductive.Poyang Lake and the surrounding counties of total iron content is not very high, and the change is not significant, variations in the range of16.3～38.87g/Kg,25.8g/Kg average value.Throughout the total iron content in different section of the trend is not big also, basically maintained at24.01-31.54g/Kg around.The soil pH value, Eh and the environmental factors such as soil organic matter and active iron content was significantly correlated. Active iron content increased with the depth of soil, content decreased, and active iron in dry season than early flood season.2. Poyang Lake wetland soil on phosphorus adsorption is a complex dynamic process, this paper takes Poyang Lake Baishazhou wetland soil material, on soil phosphorus sorption characteristics and their influence factors research. The results showed that soil on phosphorus adsorption in lh after reaching steady state, is in a dynamic balance, by using Langmuir equation, calculating soil on phosphorus adsorption capacity, maximum buffering capacity and equilibrium constants are:Xm=333.33; MBC=1250mg/Kg; K=3.75. Environmental factors on wetland soil phosphorus adsorption by a greater impact, the study found that, when the solution of Fe3+concentration is too large, will P adsorption capacity produced significant inhibition; wetland soil P adsorption capacity increases with pH increasing, wetland soil phosphorus adsorption by pH significantly; temperature on soil phosphorus adsorption effect the larger, temperature, adsorption amount greater than; water, ionic strength, Fe2O3content and Fe3+concentration on phosphorus adsorption has inhibitory action.3. Poyang Lake wetland soil on phosphorus release process is reversible, i.e. wetland soil adsorption of phosphorus can again be released.This paper takes Poyang Lake Baishazhou wetland soil material, on soil phosphorus release characteristics and their influence factors research.The results showed that soil on phosphorus release in5h after achieving balance; when Fe3+concentration is too large, the phosphor release a quantity to have apparent stimulative effect; pH on soil phosphorus release significantly, in different pH value, soil phosphorus release amount were significantly different.The ratio of water and soil, ionic strength and Fe3+concentration on phosphorus release had promoting action.