Phosphorus In Interstitial Water Research Articles

Exogenous paths regulate electron transfer enhancing sediment phosphorus immobilization

The lack of electron acceptors in anaerobic sediments leads to endogenous phosphorus release and low removal efficiency of organic pollutants. This study introduced electrodes and iron oxides into sediments to construct electron network transport chains to supplement electron acceptors. The sediment total organic carbon (TOC) removal efficiencies of closed-circuit (CC) and closed-circuit with Fe addition (CC-Fe) were estimated to be 1.4 and 1.7 times of the control. Unlike the fluctuation of phosphorus in the overlying water of the controls, the CC-Fe was stabled at 0.04–0.08 mg/L during the 84-d operation. The phosphorus in interstitial water of CC-Fe was 30 % less than in control, whereas in sediment, the redox sensitive phosphorus was increased by 14 %, indicating phosphorus was preferred to fix into sediments rather than interstitial water. This is important to reduce the risk of endogenous phosphorus returning to the overlying water. Microbial community analysis showed that the multiplication of Fonticella in CC-Fe (20 %) was 1.8-fold of control (11 %) which improved the TOC removal efficiency. While electroactive microorganisms accumulated near the electrode reduced the abundance of Fe-reducing bacteria, such as Desulfitobacterium (2.4 %), leading to better phosphorus fixation. These findings suggest a strategy for the efficient bioremediation of endogenous pollution in water, with broader implications for regulating electron transport paths and element cycles in aquatic environments.

Dynamics of Phosphorus Content in the Water-Sediment Interface of Wetlands in a Mid-Temperature Steppe.

In order to reveal dynamics changes in phosphorus release from the sediments of wetlands in a mid-temperature steppe without external phosphorus input, the relationship between phosphorus content in the overlying water, sediment, and interstitial water was studied using the variables control method. The results showed that, during the incubation period, the content of total phosphorus in the overlying water and the content of total phosphorus in interstitial water both presented in the order of August > September > July. Furthermore, the correlation relationships between phosphorus content in the overlying water, total phosphorus in the interstitial water, and the ratios of sediment Olsen-P to total phosphorus in the interstitial water, indicated that Olsen-P might be a kind of release form of phosphorus - from the sediment to the overlying water of the wetlands in Hulunbeier steppe, without external phosphorus input. This article is protected by copyright. All rights reserved.

Dynamics of Phosphorus Content in the Water-Sediment Interface of Wetlands in a Mid-Temperature Steppe.

In order to reveal dynamics changes in phosphorus release from the sediments of wetlands in a mid-temperature steppe without external phosphorus input, the relationship between phosphorus content in the overlying water, sediment, and interstitial water was studied using the variables control method. The results showed that, during the incubation period, the content of total phosphorus in the overlying water and the content of total phosphorus in interstitial water both presented in the order of August > September > July. Furthermore, the correlation relationships between phosphorus content in the overlying water, total phosphorus in the interstitial water, and the ratios of sediment Olsen-P to total phosphorus in the interstitial water, indicated that Olsen-P might be a kind of release form of phosphorus - from the sediment to the overlying water of the wetlands in Hulunbeier steppe, without external phosphorus input.

Occurrence and internal loadings of nitrogen and phosphorus in the sediment of Lake Baiyangdian

白洋淀环境整治对区域生态文明建设具有重要意义，然而，目前对加剧白洋淀富营养化的内源氮、磷污染负荷依然缺乏系统的研究.本研究以野外调研和室内培养实验相结合形式，在白洋淀主要水域内采集原位柱状沉积物样品，详细地研究了白洋淀沉积物中氮、磷赋存形态、间隙水中氮、磷剖面特征以及沉积物-水界面氮、磷交换特征.结果表明，白洋淀沉积物总氮、总磷含量分别为1230.8~9559.0 mg/kg（均值2379.5 mg/kg）和344.4~915.4 mg/kg（均值608.4 mg/kg），氮、磷累积污染量大.沉积物中铵态氮赋存量大（3.2~175.8 mg/kg），由此导致间隙水中铵态氮浓度较高，最高达到28.8 mg/L.沉积物磷形态以Ca-P和Fe-P为主，分别占总量的38.3%~76.1%和3.98%~18.0%，间隙水中磷酸盐浓度已接近甚至高于国内外典型富营养湖区.间隙水中高浓度的铵态氮和磷酸盐导致沉积物-水界面氮、磷交换通量较高，铵态氮平均释放和扩散通量分别为106.37和12.42 mg/（m²·d）；磷酸盐平均释放和扩散通量分别为15.06和2.33 mg/（m²·d），沉积物内源氮、磷污染负荷较高，已严重威胁到白洋淀水环境质量，迫切需要整治.其中，北部河口区域以及中部府河入湖区和人口密集活动区沉积物氮、磷内源负荷尤为突出，应成为白洋淀沉积物内源污染整治的关键区域.;The environmental restoration of Lake Baiyangdian is of great significance for regional construction of ecological civilization. However, information on the internal loadings of nitrogen and phosphorus, which aggravated the eutrophic status of Lake Baiyangdian, is still limited. In this study, a detailed field survey was carried out to investigate the occurrence and fractions of nitrogen and phosphorus in the sediment, the profiles of nitrogen and phosphorus in interstitial water, and the exchanges of nitrogen and phosphorus across the sediment-water interface. A series of in situ sediment core samples were collected in important water areas of Lake Baiyangdian for the study. Results showed that the contents of total nitrogen and total phosphorus in the sediments were in the range of 1230.8-9559.0 mg/kg (average:2379.5 mg/kg) and 344.4-915.4 mg/kg (average:608.4 mg/kg), respectively. A large quantity of the cumulative pollution of nitrogen and phosphorus was discovered. The high levels of ammonium nitrogen in the sediments (3.2-175.8 mg/kg) led to high concentrations of ammonium nitrogen in the interstitial water, with the highest concentration of 28.8 mg/L. The phosphorus forms in the sediments were largely Ca-P and Fe-P, accounting for 38.3%-76.1% and 3.98%-18.0%, respectively. The phosphate concentrations in the interstitial water were close to or even higher than those in typical eutrophic lakes around the world. The high levels of ammonium nitrogen and phosphate in the interstitial water resulted in high exchange fluxes of nitrogen and phosphorus across the sediment-water interface. The average release and diffusive fluxes of ammonium nitrogen were 106.37 mg/(m²·d) and 12.42 mg/(m²·d), respectively. The average release and diffusive fluxes of phosphate were 15.06 mg/(m²·d) and 2.33 mg/(m²·d), respectively. The high internal loadings of nitrogen and phosphorus in the sediments are now serious threat to the water environmental quality of Lake Baiyangdian. Urgent measures should be carried out to reduce the internal loadings. Especially, the northern estuary area and the central heavily populated area under the influence of the Fuhe River had higher internal loadings of nitrogen and phosphorus than other areas. These two areas should be given top priority during the remediation of internal loadings in Lake Baiyangdian.

Phosphorus in Interstitial Water Induced by Redox Potential in Sediment of Dianchi Lake, China

The sediment redox potential was raised in the laboratory to estimate reduction of internal available phosphorus loads, such as soluble reactive phosphorus (SRP) and total phosphorus (TP), as well as the main elements of sediment extracts in Dianchi Lake. Several strongly reducing substances in sediments, which mainly originated from anaerobic decomposition of primary producer residues, were responsible for the lower redox potential. In a range of −400 to 200 mV raising the redox potential of sediments decreased TP and SRP in interstitial water. Redox potentials exceeding 320 mV caused increases in TP, whereas SRP maintained a relatively constant minimum level. The concentrations of Al, Fe, Ca 2+, Mg 2+, K +, Na + and S in interstitial water were also related to the redox potential of sediments, suggesting that the mechanism for redox potential to regulate the concentration of phosphorus in interstitial water was complex.

Distribution of Kinetic Parameters of Alkaline Phosphatase in Sediments of Shallow Lakes

东湖沉积物磷酸酶在较高的pH范围内表现出较高活性,故为碱性磷酸酶.东湖与严西湖沉积物中碱性磷酸酶的动力学参数表现出明显的空间异质性,且与间隙水和表层水中正磷酸根浓度无明显的对应关系.此外,它们在垂直方向上亦极具变化,除在沉积物表面显示较高催化效率之外,较深层面(约距表面8-12cm)亦有类似峰值,这一结果补充说明了湖泊沉积物磷循环的另一活跃区域以及相应的生物化学机制.;Phosphatase in sediments in Lake Donghu, Wuhan can be classified as alkaline phosphatase, showing a higher activity at alkaline pH ranges.The kinetics of alkaline phosphatase exhibited a distinct spatial heterogeneity in sediments of Lake Donghu and Yanxihu, which is not significantly correlated with the concentrations of soluble reactive phosphorus in interstitial water, overlying water and surface water.Furthermore, it varied greatly in vertical profiles, and peaked both at surface and in a middle layer (8-12 cm beneath the surface).The latter added a new dimension in which P cycling mediated by some biochemical mechanisms is active.

Phosphorus in interstitial water: methods and dynamics

Phosphorus in interstitial water: methods and dynamics