Sediment dredging can permanently remove pollutants from an aquatic ecosystem, which is considered an effective approach to aquatic ecosystem restoration. In this work, a 2-year field simulation test was carried out to investigate the effect of dredging on nitrogen cycling across the sediment-water interface (SWI) in Lake Taihu, China. The results showed that simulated dredging applied to an area rich in total organic carbon (TOC) and total nitrogen (TN) slightly reduced the NH4(+)-N release from sediments while temporarily enhanced the NH4(+)-N release in an area with lower TOC and/or TN (in the first 180 days), although the application had a limited effect on the fluxes of NO2(-)-N and NO3(-)-N in both areas. Further analysis indicated that dredging induced decreases in nitrification, denitrification, and anaerobic ammonium oxidation (anammox) in sediments, notably by 76.9, 49.0, and 89.9%, respectively, in the TOC and/or TN-rich area. Therefore, dredging slowed down nitrogen cycling rates in sediments but did not increase N loading to overlying water. The main reason for the above phenomenon could be attributed to the removal of the surface sediments enriched with more TOC and/or TN (compared with the bottom sediments). Overall, to minimize internal N pollution, dredging may be more applicable to nutrient-rich sediments.

Effects of sediment dredging on nitrogen cycling in Lake Taihu, China: Insight from mass balance based on a 2-year field study

Nitrogen budget at sediment-water interface altered by sediment dredging and settling particles: Benefits and drawbacks in managing eutrophication.

Effects of sediment dredging on internal phosphorus: A comparative field study focused on iron and phosphorus forms in sediments

Sediment in-situ bioremediation by immobilized microbial activated beads: Pilot-scale study.

Effect of dredging and capping with clean soil on the mitigation of algae-induced black blooms in Lake Taihu, China: A simulation study

A laboratory experiment for studying the effects of sediment dredging on microbial activity and functional diversity of microbial community of sediments was carried out through one year.Using incubation of undredged(control) and dredged cores,we found that dredging the upper 30cm layer of sediment remarkably affected physico-chemical and microbial characteristics of sediments in the study area of Meiliang Bay,Lake Taihu.The microbial activity in dredged sediments was significantly lower(P0.05)than that in undredged sediments.Sediment dredging affected considerably microbial activity in sediments,and the microbial activity in dredged sediments could not recovery in one year experiment.Sediment dredging also affected the functional diversity of microbial community in sediment,the diversity index of microbial community in early dredged sediments was significantly lower (P0.05) than that in undredged sediments.Sediment dredging modified the community composition of sediment microbial ecosystem and resulted in decreasing of diversity of microbial community.Sediment dredging affected microbial activity and functional diversity of microbial community,which consequently affected the cycling of biogenic elements in sediments.

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湖泊底泥疏浚环境效应:iv.对沉积物微生物活性与群落功能多样性的影响及其意义