Aluminum distribution heterogeneity and relationship with nitrogen, phosphorus and humic acid content in the eutrophic lake sediment☆
Graphical abstract
Introduction
Aluminum (Al), the most abundant metal element on the earth's crust, widely services in human industrial and agricultural activities (Novaes et al., 2018). More and more Al intrude into the ecosystem, leading to poison function on animal and inhibition on crop productivity (Yu et al., 2015, Chen et al., 2018, Pinheiro et al., 2018). Additionally, recent years witnessed the increasing application of Al-salt flocculants in eutrophic lake management, such as the sewage treatment, emergency control of alga bloom and controlling phosphorus (P), etc. (Welch and Cooke, 1999, Rott et al., 2017). Besides, the expansively environment acidification also facilitate the Al dissolving out from mineral and soil and inflow into the water column via surface runoff. Previous researches (Robert and Richard, 1999, Srinivasan et al., 1999, Kopacek et al., 2005, Wang et al., 2010a, Wang et al., 2010b) revealed that water soluble Al ranged 14.3–1170 μg L−1 in Norway, Britain and the USA, being higher than that in major rivers (1.7–52.9 μg L−1) and wetland lake (261–429 μg L−1) in China (Reinhardt et al., 2004, Wang, 2012). Aqueous Al will be toxic to the aquatic animal and plants when it beyond safe concentration (Xie et al., 2015).
A series of chemical reactions and physical migration, such as hydrolysis, chelation (Al bind to PO4−, dissolved organic matter (DOM), etc.) (Namiesnik and Rabajczyk, 2010), flocculation and precipitation, occurred when Al-salt flocculants applied into water treatment (Kasper et al., 2005). Aqueous Al is comprised of inorganic monomer Al species and polymer species, and their proportion vary with pH, cationic/anion, P-coalition, soluble organic matter, water flow velocity (Robert and Richard, 1999, Feng et al., 2015). When Al-salts entering water, firstly, polymeric hydrolysate of Al3+ trigger the destabilization of colloidal particles through electrical neutralization, then the secondary bulky agglomerated particles rapidly settle due to its adsorption-bridging effect and eventually be removed. Meanwhile, Al3+ will adsorb and complex the harm ions (Namiesnik and Rabajczyk, 2010, Quinones et al., 2016). Al-toxicity ecological risk may occur when toxic forms of Al-salt are producted and the concentrations accumulate beyond a threshold level (Guo et al., 2012). However, previous Al-salt researches mainly focused on the terrestrial ecosystems (He et al., 2017). There has been relatively little study on the Al migration and relationships with sediments possessing different physico-chemical properties when Al-salt entering eutrophic lakes.
Eutrophic lakes are typically characterized by highly endogenous nitrogen (N), P nutrient and humus content (Paytan et al., 2017). The application of Al-sulfate in water pretreatment and lake management was originally intended to reduce excessive dissolved P in water and inhibit P release from sediments (Lin et al., 2017a), by forming Al-phosphate complexes (Babatunde and Zhao, 2010, Chu et al., 2018) and covering a floc of relatively insoluble Al(OH)3 over sediment surface (Jiri et al., 2005, Yu et al., 2018), which is pH-dependent. Besides, inorganic phosphate can also adsorb onto Al2O3 and Al(OH)3, that highly dependent on the type of Al-salts and environmental conditions (Ma et al., 2018). In addition, humic acid (HA) is important complexing agent of metal ions, which not only can reduce their content, but also can affect the toxicity and biological effectiveness of metal ions (Namiesnik and Rabajczyk, 2010, Xu et al., 2014). Humus form both weak and strong complexes with Al by the carboxylic acid functional groups (Lin et al., 2014, Jin et al., 2018). The Al-detoxifying capacity of HA is positively correlated with the relative position of OH/COOH groups in main chain and their capacity to form stable ring structure with Al (Tamer et al., 2015, Niu et al., 2018), and HA contributes to Al speciation in natural waters (Wang et al., 2010a, Wang et al., 2010b, Song et al., 2019). Besides, N is an important component of humus, and Al play important role in regulating soil N transformation and in N cycle (Zhao and Shen, 2018). Accordingly, high humus content, high N and P nutrition load and complex environmental condition, all these can affect the migration and transformation of Al-salt in the eutrophic lake systems as well as its bioavailability. Hence, it is important to reveal Al migration rule in the eutrophic lakes.
The Hangzhou West Lake, China, is famous for long culture history and urban landscape. It still faces eutrophication problem (Lin et al., 2017b). To effectively improve the water quality, 4 × 105 m3 d−1 water from the Qiantang River are diverted into the lake since 2002, by different paths after disposing through Al-salts flocculation precipitation (Jin et al., 2015). So a certain content of residual Al-salts (94–115 μg L−1) from water treatment plant flows into the lake with the pretreated water every day, and residual Al-salts could accumulated onto the sediment surface over a long period. The Al-salts from water diversion into the West Lake represents the way of exogenous Al into the eutrophic lakes. So the West Lake provides a research pilot for the study of exogenous Al-salts into the eutrophic lakes in situ.
In this study, how do Al spatio-temporal distributes when Al-salts flows into the eutrophic lake and the migration and transformation characteristics of Al-salts in different trait of sediments was investigated. Besides, the distribution characteristic of total nitrogen (TN), humus and different P species in the sediment of the West Lake was investigated for both horizontal and vertical dimensions, based on which the relationships among Al and TN, humus and different P species were analyzed. Results are of vital importance for evaluating environmental risks of Al-salt in aquatic ecosystems and helpful to eutrophic lakes management.
Section snippets
Sampling sites
The sub-lakes, Maojiabu Lake (30°14′15–24″N, 120°07′36–45″E) and Xiaonanhu Lake (30°13′41–47″N, 120°08′30–36″E), situated in west and southwest of the West Lake, Hangzhou, China, are the important direct inlets of water diversion (Fig. 1), and were chosen as the study area. The two sub-lakes are significantly different in area, division time and amount, sediment depth and moisture, and human disturbance (Table 1). There are two fixed inlets in Xiaonanhu Lake, where the division amount of Inlet
Al distribution characteristic in different sites
The spatial heterogeneity in the surface sediments was evident among the sampling sites and between the upper and lower layer, with one gradient formation. In Maojiabu Lake, the sediment Al content ranged 0.463–1.154 g kg−1 (Fig. 2). The highest Al content of upper layer and lower layer sediment (0.765 g kg−1 and 1.154 g kg−1) both located in M3, respectively being 1.65-fold and 1.25-fold to the minimum (0.463 g kg−1 and 0.924 g kg−1), which presented in M1. Conformably, the upper layer
Al distribution heterogeneity in two sub-lakes of hangzhou West Lake
Polyaluminum chloride and Al sulfate are typically applied as liquid flocculants in sewage treatment and emergency control of lakes P load (Welch and Cooke, 1999, Rott et al., 2017). Once Al-salt entering lakes, hydrolysis take place and various macromolecular complexes of a colloidal nature come into existence, which are in equilibrium with one another: Al3+ ↔ AlOH2+ ↔ Al2(OH)24+ ↔ Al3(OH)45+ ↔ Al8(OH)204+ ↔ Al13O4(OH)247+ ↔Al(OH)3 (Namiesnik and Rabajczyk, 2010). Over time, the floc will be
Conclusions
Obvious spatial distribution heterogeneity of Al in sediment vertical direction and horizontal direction following water flow existed in eutrophic lakes. Higher Al content distributed in upper layer sediment in lake with more human disturbance, which could lead the suspended particle matter containing Al-salts to resuspend. Al contents in sediment are closely related to flow field of entering the water body, and geographical location of the lake. Al contents significantly correlated with
Acknowledgments
This work was supported by the National Natural Science Foundation of China (No.31830013), the State Key Laboratory of Freshwater Ecology and Biotechnology (2017FB05), thez Major Science and Technology Program for Water Pollution Control and Treatment in the 12th Chinese Five-Year Plan (No. 2012ZX07101007-005). We thank Jian Sun and Lai Wang from the Institute of Hydrobiology, Chinese Academy of Sciences for fieldwork and technical assistance.
References (63)
- et al.
Laboratory investigation of the phosphorus removal (SRP and TP) from eutrophic lake water treated with aluminium
Water Res.
(2006) - et al.
Characterization of aluminium-based water treatment residual for potential phosphorus removal in engineered wetlands
Environ. Pollut.
(2009) - et al.
Equilibrium and kinetic analysis of phosphorus adsorption from aqueous solution using waste alum sludge
J. Hazard Mater.
(2010) - et al.
Distribution and phytotoxicity of soil labile aluminum fractions and aluminum species in soil water extracts and their effects on tall fescue
Ecotoxicol. Environ. Saf.
(2018) - et al.
Molecular insights into the mechanism and the efficiency-structure relationship of phosphorus removal by coagulation
Water Res.
(2018) - et al.
Effect of humic acid on water chemistry, bioavailability and toxicity of aluminium in the freshwater snail, Lymnaea stagnalis, at neutral pH
Environ. Pollut.
(2006) - et al.
Effect of pH with different purified aluminum species on coagulation performance and membrane fouling in coagulation/ultrafiltration process
J. Hazard Mater.
(2015) - et al.
Involvement of antioxidative defense system in rice seedilings exposed to aluminum toxicity and phosphorus deficiency
Rice Sci.
(2012) - et al.
Nitric oxide inhibits aluminum-induced programmed cell death in peanut (Arachis hypoganea L.) root tips
J. Hazard Mater.
(2017) - et al.
A simple model for predicting aluminum bound phosphorus formation and internal loading reduction in lakes after aluminum addition to lake sediment
Water Res.
(2014)
Influence of coagulation mechanisms on the residual aluminum - the roles of coagulant species and MW of organic matter
J. Hazard Mater.
Selective binding behavior of humic acid removal by aluminum coagulation
Environ. Pollut.
Effect of citric acid on aluminum hydrolytic speciation
Water Res.
Mobile phosphorus stratification in sediments by aluminum immobilization
Chemosphere
Fate of hydrolyzed Al species in humic acid coagulation
Water Res.
Impacts of residual aluminum from aluminate flocculant on the morphological and physiological characteristics of Vallisneria natans and Hydrilla verticillata
Ecotoxicol. Environ. Saf.
Beneficial effects of aluminum enrichment on nitrogen-fixing cyanobacteria in the South China Sea
Mar. Pollut. Bull.
Effect of water treatment residuals on soil phosphorus, copper and aluminum availability and toxicity
Environ. Pollut.
Speciation matching mechanisms between orthophosphate and aluminum species during advanced P removal process
Sci. Total Environ.
Effects of dissolved and fixed humic acid on Eu(III)/Yb(III) adsorption on aluminum hydroxide: a batch and spectroscopic study
Chem. Eng. J.
Aluminum sulfate (alum) application interactions with coupled metal and nutrient cycling in a hypereutrophic lake ecosystem
Environ. Pollut.
Aluminum: a potentially toxic metal with dose-dependent effects on cardiac bioaccumulation, mineral distribution, DNA oxidation and microstructural remodeling
Environ. Pollut.
Internal loading of phosphate in lake erie central basin
Sci. Total Environ.
Removal of phosphorus from phosphonate-loaded industrial wastewaters via precipitation/flocculation
J. Water Pro. Eng.
Synergistic effects of various in situ hydrolyzed aluminum species for the removal of humic acid
Water Res.
Effects of fulvic acid and humic acid on aluminum speciation in drinking water
J. Environ. Sci.
Factors effecting aluminum speciation in drinking water by laboratory research
J. Environ. Sci.
Influence of shear force on floc properties and residual aluminum in humic acid treatment by nano-Al-13
J. Hazard Mater.
Interactions of riverine suspended particulate matter with phosphorus inactivation agents across sediment-water interface and the implications for eutrophic lake restoration
Chem. Eng. J.
Introducing hydrate aluminum into porous thermally-treated calcium-rich attapulgite to enhance its phosphorus sorption capacity for sediment internal loading management
Chem. Eng. J.
Effect of crystallization of settled aluminum hydroxide precipitate on “dissolved Al”
Water Res.
Cited by (21)
Necroptosis and NLPR3 inflammasome activation mediated by ROS/JNK pathway participate in AlCl<inf>3</inf>-induced kidney damage
2023, Food and Chemical ToxicologySpatiotemporal variation and influencing factors of nitrogen and phosphorus in lake sediments in China since 1850
2022, Journal of Cleaner ProductionCitation Excerpt :They can reveal the biodiversity, evolution, climate change and anthropic factors of lakes under long-term conditions in lake basins (Bao et al., 2021; Foucher et al., 2020; Hillman et al., 2020). The mass accumulate rates (MARs) of lake sediments and nutrient elements (N and P) are important parameters reflecting the long-term evolution of lake environments and the eutrophication of lakes (Lin et al., 2019a; Qin et al., 2020; Tao and Lu, 2020). Since 1850, the MARs and nutrient concentrations of most lake sediments have increased significantly (Wang et al., 2018; Xu et al., 2017).
Impact of submerged vegetation, water flow field and season changes on sediment phosphorus distribution in a typical subtropical shallow urban lake: Water nutrients state determines its retention and release mechanism
2022, Journal of Environmental Chemical EngineeringCitation Excerpt :Hangzhou West Lake in China, a typically urban shallow lake, was classified as a World Heritage Site in 2011 and currently in a state of eutrophication [2]. The sublakes (e.g. Maojiabu Lake, Wuguitan Lake, and Yuhuwan Lake), located in west of the West Lake, Hangzhou, China, which belong to the upstream locations due to the flow fields induced from the water supplement of Longhongjian and Chishanxi, and water diversion project [28]. Consist of the two streams, originating from Longjing Spring and Yuegui Mountain, Longhongjian Stream supply the water at the west location of West Lake, Maojiabu.
- ☆
This Paper has been recommended for acceptance by Jörg Rinklebe