| Phosphorus is an important biogenic element and phosphine has been confirmed to be widespread in the environment. The discovery of phosphine let people rediscover the phosphorus cycle. Now there are wide researches about phosphine in lake, land, marsh and air, but only a few are about the phosphine in marine environment, which now focused mainly on phosphine distribution and emission. There is little information available about phosphine transformation in marine environment. Therefore, it is of great significance to study the effects of environmental factors on the phosphine transformation process in seawater and it will help a lot to make clear the function and status of phosphine in biogeochemical phosphorus cycle.Chose several primary environmental factors according to documents, and laboratory experiments were carried out to study the effects of these factors on phosphine transformation. The results are as follows:Different light conditions can affect the phosphine transformation apparently. Sized down the promotion effect on phosphine transformation and found out that UVC > UVB > daylight > UVA > dark. UVC in per irradiance unit can make bigger promotion of phosphine transformation than UVB.O2 can make promoter action for phosphine transformation but not apparently. There are other constituents which can promote phosphine transformation. O3 have greater effects on phosphine transformation than O2.Salinity of artificial seawater has weak inhibition effects on phosphine transformation due to its effects on gas dissolvability. The increase of salinity of natural seawater seems to promote phosphine transformation because of the increase of other constituents'concentration in it. In our research, acidic or alkaline environment can be benefit for phosphine transformation. When pH=10, the phosphine transformation progress was taken mainly in the first 3 hours.Mn, Cu, Fe in low concentration shows no effects on phosphine transformation. Fe in high concentration(6×10-7-3×10-4mol/L) can react with phosphine as an oxidant and the phosphine transformation ratio can be as high as 18.63%. Pd can catalyze phosphine transformation even at low concentration(0-3×10-8mol/L) and can get the highest phosphine transformation ratio when with the concentration of 7.50×10-7mol/L. It would show inhibition when the concentration is higher than this value. The phosphine transformation process was fast at first, and then got slow. When Pd concentration was 7.50×10-7mol/L, the phosphine transformation was taken primarily in the first hour.
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