首页|Short-term phosphorus transformation in shallow-lake sediments mediated by nitrogen and iron under anoxic conditions
Short-term phosphorus transformation in shallow-lake sediments mediated by nitrogen and iron under anoxic conditions
扫码查看
点击上方二维码区域，可以放大扫码查看
原文链接
NETL
NSTL
万方数据
The release of internal phosphorus(P)is a key and complex process relative to a lake's nutrient levels.The P response to nitrogen input should be clarified to obtain better detail,especially with respect to the mediation role of iron(Fe)connecting nitrogen and P.A simulation study was done in batch vials con-taining sediment and overlying water collected from Lake Moshui—a shallow lake.Because of nitrate(NO3-)input,the abundances of Firmicutes and Proteobacteria at the phylum level increased,as did the abundances of Crenothrix,Sideroxydans,and Flavobacterium at the genus level.Moreover,nitrate input enhanced the proliferation of nitrate-reducing Fe(Ⅱ)oxidization bacteria and the activity of denitrifying enzyme in sediment,but decreased the concentrations of total phosphorus(TP),soluble reactive P,and enzymatically hydrolyzable P in the water phase.The suppressive effect of nitrate on P release was mainly attributed to the increase in Fe(Ⅲ)(hydr)oxides generated by Fe(Ⅱ)oxidation.With sequential extraction,two types of dominant iron fractions-easily reducible oxides and reducible oxides(Feoxi and Feox2,respectively)-seemed to contribute to the fixation of P largely in the sediment.In addition,more P is converted to Feox2,which is induced by the transformation of Feox1 to Feox2.Driven by nitrate,a higher content of P bound to Feox1 and Feox2 was observed after a 7-day incubation,indicating the potential function of the Fe(Ⅱ)oxidation process.The current study revealed that the P transformation is influ-enced by nitrate input from the angle of iron as the connecting bridge to better understand the geochemical cycle of P in the anoxic environment of lakes.
NETL
NSTL
万方数据
