Spatial variation of soil phosphorus in the water level fluctuation zone of the Three Gorges Reservoir: Coupling effects of elevation and artificial restoration.

The water level fluctuation zone (WLFZ) is a distinctive and important component of the reservoir ecosystem. Due to periodic inundation, the fraction, spatial distribution, and chemical reactivity of soil phosphorus (P) within the WLFZ can potentially impact the loading of P into reservoir waters. However, a detailed study of this subject is lacking.

Suspended phosphorus sustains algal blooms in a dissolved phosphorus-depleted lake.

The expansion of algal bloom in surface waters is a global problem in the freshwater ecosystem. Differential reactivity of organic phosphorus (P) compounds from organic debris, suspended particulate matter (SPM), and sediment towards hydrolysis can dictate the extent of supply often limited inorganic P (P) for algal growth, thereby controlling the extent of bloom. Here, we combined solution P-31 nuclear magnetic resonance (P NMR), sequential extraction, enzymatic hydrolysis, and 16S rRNA measurements to characterize speciation and biogeochemical cycling of P in Lake Erhai, China.

Fuel from within: Can suspended phosphorus maintain algal blooms in Lake Dianchi.

Extensive algal bloom in the surface water is a pressing issue in Lake Dianchi that causes lake restoration to be difficult owing to complex and variable phosphorus (P) sources in the water column. P released from algae, suspended particles (SS), and sediment can provide sustainable P sources for algal blooms. However, little is known regarding the dynamic of P speciation in these substances from different sources.

Effects of cascade dam on the distribution of heavy metals and biogenic elements in sediments at the watershed scale, Southwest China.

Cascade dam has important effects on the magnitude and dynamics of sediment particles, heavy metals, and biogenic elements in reservoirs. However, systematic studies on the interception effect of cascade dam on the various elements that occur in rivers at the watershed scale are lacking. The aims of this study were to (1) assess the interception effect of a cascade dam on heavy metals and biogenic elements and (2) investigate the key factors of these effects of the cascade dam.

Method for phosphate oxygen isotopes analysis in water based on in situ enrichment, elution, and purification.

The phosphate oxygen isotope (δO) ratio has been proven to be an effective tool to trace the sources and biogeochemical cycles of phosphorus (P) in aquatic ecosystems. However, the enrichment of phosphate (PO) and the removal of impurities are quite complex and easy to cause PO loss in current δO analytical methods. Moreover, the δO value obtained by the commonly-used instantaneous sampling method is more of the instantaneous information of P, which is accidental or uncertain for accurate identification of the P source.

Removal of phosphate by aluminum-modified clay in a heavily polluted lake, Southwest China: Effectiveness and ecological risks.

Lake eutrophication is a main water environmental problem. When the extraneous nutrients are effectively controlled, nutrients in water mainly source from endogenous release from the sediment. In situ passivation is an important pollution control technique for endogenous pollution in lakes or reservoirs.

Pretreatment method for the analysis of phosphate oxygen isotope (δO) of different phosphorus fractions in freshwater sediments.

Accurate measurement of the oxygen isotopic composition of dissolved phosphate (δO) of different phosphorus (P) fractions in lacustrine sediments is very difficult because of the influence of large amounts of impurities. In this study, we developed a five-step method for obtaining high purity AgPO sample for the analysis of δO of different P fractions in freshwater sediments. Sedimentary P was divided into NaHCO-P, NaOH-P and HCl-P by chemical sequential extraction.

In situ, high-resolution evidence of phosphorus release from sediments controlled by the reductive dissolution of iron-bound phosphorus in a deep reservoir, southwestern China.

Reservoirs in southwestern China are encountering the challenge of eutrophication, in which internal phosphorus (P) release from sediments plays an important role. Studies on the high-resolution profile variations and release mechanisms of P at the sediment-water interface (SWI) are rare in these reservoirs until now. In this study, monthly monitoring (Nov 2017 to Oct 2018) using a composite diffusive gradient in thin films (DGT) technique was taken to determine the temporal and vertical profile variations of the DGT-labile P (Fe) at the SWI in Hongfeng Reservoir.

Assessment on the effects of aluminum-modified clay in inactivating internal phosphorus in deep eutrophic reservoirs.

Aluminum-salt inactivating agents are extensively applied to the restoration of lakes polluted by internal phosphorus (hereinafter referred to as "P"). However, there is a lack of micromechanism information regarding the sediment P cycle and its interactions with aluminum salts, which has restricted the engineering applications of aluminum salts. In this study, a sediment core incubation system was used to simulate the influence of aerobic and anaerobic conditions on the effectiveness and stability of aluminum-modified clay (AMC).