Characteristics Of Phosphorus Adsorption And Release By Sediment Of The Suzhou River

We study the release-adsorption of P from sediments in laboratory to research the ability and rule of sediments absorbing-releasing P and the effecting factors. At the same time, we ascertain the depth for dredging up to reduce the release from sediments and save power and capital. By the research and simulating indoor, we want to master the inner pollute from Suzhou river and its effect on water quality, to provide basic data for water environment and appraising system. The results were given as follows:1. pH of water is one of the important factor effecting the adsorption of the sediments. With the increasing of water pH, P adsorbing capacity of sediment decreased. So it is good to water quality by controlling the pH between neutral and slight acidic condition.2. With the increasing of phosphate concentration, the phosphate adsorption capacity of sediment increased. The higher ratio of water to sediment, the lower phosphorus absorbing capacity on sediment will be.3. The sediments from Suzhou river can absorb P in static state without outer input.4. In anaerobic, the released P from sediments are larger than in aerobic. So we should control the quantity of consumer oxygen and increase the level of dissolve oxygen to improve the water quality.5. It is known that from the absorbing ability of different layer sediments: the sediments of 0-5cm is most polluted. On the contrary, the 5-10cm is lest polluted. So when dredging up, we can clear the first 5cm sediments to save money and power.In conclusion, the sediments are not only the resource but also the deposit for the nutrients. In today's condition, the sediments from Suzhou river can absorb the nutrients and improve the water quality without inputting. So how to stop the outer pollution is the key for improving the water quality of Suzhou river.