Dynamics and endogenous release potential of phosphorus at sediment-water interface in Chaohu lakeshore in spring and summer
By using the traditional manual sampling method and diffusive gradients in thin films technique(DGT),we analyzed the phosphorus species in overlying water,interstitial water,and sediment,and DGT-labile phosphorus(DGT-P)and DGT-labile iron(DGT-Fe)in interstitial water,to investigate the dynamics and diffusion flux of phosphorus in the northwestern lakeshore of Chaohu Lake during the spring and summer seasons.Significant decrease of phosphorus in overlying water in early summer was likely due to its rapid uptake by algae.While significant seasonal variations of phosphorus species in interstitial waters were observed.Authigenic phosphorus was the primary form of inorganic phosphorus in the lakeshore sediments.Lower level phosphorus but higher release potential from sediments in the water-level fluctuation zone(S1,S2)in northwestern Chaohu Lake were observed in contrast to those in the dam isolation zone(S3),due to their different level of organic matter and hydrodynamic disturbance.The release potential of endogenous phosphorus from sediments in summer is higher than that in spring.Correlation analysis between DGT-P and DGT-Fe indicated that the release of endogenous phosphorus from sediments in water-level fluctuation zone is mediated mainly through the iron-bound phosphorus reduction,while those in S3 is weak.
Chaohu lakelakeshore zonesedimentsdiffusive gradients in thin films techniquephosphorus
万方数据
维普
