The mobility of phosphorus, iron, and manganese through the sediment–water continuum of a shallow eutrophic freshwater lake under stratified and mixed water-column conditions

Giles, Courtney D.; Isles, Peter D. F.; Manley, Tom; Xu, Yaoyang; Druschel, Gregory K.; Schroth, Andrew W.

doi:10.1007/s10533-015-0144-x

Cited by 82 publications

(62 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Persistent suboxic conditions observed in bottom water of MB throughout the winter generated high and progressively increasing concentrations of truly dissolved Mn and P, and subsequent enrichment in colloidal Fe, all due to the reductive dissolution of Fe/Mn (oxy)hydroxides near the SWI (Schroth et al ; Giles et al ). This loading mechanism was independently confirmed by the concentration profile of DO and Mn(II) around the SWI (Figs.…”

Section: Discussionmentioning

confidence: 99%

“…The sensor was calibrated prior to sampling using manufacturer's instructions. The near‐bottom sensor measurements may represent around 5–10 cm above the sediments due to sensor protection guard, which likely over estimates DO concentrations at the SWI where steep gradients are known to occur (Schroth et al ; Giles et al ).…”

Section: Methodsmentioning

confidence: 99%

“…Detailed sample preparation and measurement for high resolution inductively coupled plasma mass spectrometer can be found elsewhere (e.g., Schroth et al ; Joung and Shiller ) (Supporting Information Methods). Another set of water samples were collected and filtered using a 0.45 μm pore size syringe filters (Nalgene, Thermo) for DOC, total dissolved phosphorus, soluble reactive phosphorus (SRP) determination (Silveira ; Schroth et al ; Giles et al ). Unfiltered samples were used for total P (TP) (Supporting Information Methods).…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Winter weather and lake‐watershed physical configuration drive phosphorus, iron, and manganese dynamics in water and sediment of ice‐covered lakes

Joung

Leduc²,

Ramcharitar

et al. 2017

Limnology & Oceanography

Self Cite

View full text Add to dashboard Cite

While decreasing occurrence and duration of lake ice cover is well-documented, biogeochemical dynamics in frozen lakes remain poorly understood. Here, we interpret winter physical and biogeochemical time series from eutrophic Missisquoi Bay (MB) and hyper-eutrophic Shelburne Pond (SP) to describe variable drivers of under ice biogeochemistry in systems of fundamentally different lake-watershed physical configurations (lake area, lake : watershed area). The continuous cold of the 2015 winter drove the MB sediment-water interface to the most severe and persistent suboxic state ever documented at this site, promoting the depletion of redoxsensitive phases in sediments, and an expanding zone of bottom water enriched in reactive species of Mn, Fe, and P. In this context, lake sediment and water column inventories of reactive chemical species were sensitive to the severity and persistence of subfreezing temperatures. During thaws, event provenance and severity impact lake thermal structure and mixing, water column enrichment in P and Fe, and thaw capability to suppress redox front position and internal chemical loading. Nearly identical winter weather manifest differently in nearby SP, where the small surface and watershed areas promoted a warmer, less stratified water column and active phytoplankton populations, impacting biogeochemical dynamics. In SP, Fe and P behavior under ice were decoupled due to active biological cycling, and thaw impacts were different in distribution and composition due to SP's physical structure and related antecedent conditions. We find that under ice biogeochemistry is highly dynamic in both time and space and sensitive to a variety of drivers impacted by climate change.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Winter weather and lake‐watershed physical configuration drive phosphorus, iron, and manganese dynamics in water and sediment of ice‐covered lakes

Joung

Leduc²,

Ramcharitar

et al. 2017

Limnology & Oceanography

Self Cite

View full text Add to dashboard Cite

show abstract

“…Combined with lake level fluctuations, the higher flows through the reservoir contributed to the resuspension of littoral sediments and substantial increases in Fe concentrations (Figure ). Others have observed elevated Fe concentrations during winter and spring months in other reservoirs as a result of increased precipitation and snowmelt (Giles et al, ; Hongve, ; Zaw & Chiswell, ). The lack of a contaminant increase in Mn concentrations suggests that the source of suspended sediment is from the watershed, as watershed soils have a higher Fe to Mn ratio than the reservoir.…”

Section: Discussionmentioning

confidence: 95%

“…Although it is well‐known that abiotic Mn oxidation kinetics are slow under circumneutral conditions (Davison, , Morgan, ; Munger et al, ), which could help explain the Mn patterns, the dominance of soluble Fe at depth is surprising, considering that Fe oxidation occurs quickly, considerably faster than Mn (Davison, , Morgan, ). One possible explanation for these observations is that decaying cyanobacteria in the reservoir release organic acids that complex with metals and enhance solubility (see McKnight, ), and/or release metals that had accumulated in cells (see Giles et al, ). Additional work would be needed to further address the prevalence of soluble Mn and Fe in the benthic zone of the reservoir after turnover.…”

Section: Discussionmentioning

confidence: 99%

Effects of reservoir stratification and watershed hydrology on manganese and iron in a dam‐regulated river

Munger

Shahady

Schreiber

2017

Hydrological Processes

View full text Add to dashboard Cite

The presence of metals, including manganese (Mn) and iron (Fe), adversely impacts water quality. In seasonally stratified reservoirs, Mn and Fe can accumulate in the water column due to reducing conditions in sediments and be released to downstream rivers through dam discharge. In addition to reservoir stratification influences, the release of metals downstream is influenced by hydrologic conditions in the river. We examined the seasonal and spatial variability of Mn and Fe concentrations in a eutrophic, hydropower reservoir and the downstream river over a two‐year period. Overall, we found that reservoir stratification was a strong predictor of tailrace Mn and Fe concentrations but that tailrace Fe concentrations were also influenced by dam discharge. Downgradient of the tailrace, river discharge and suspended sediment were the dominant predictors of both Mn and Fe concentrations. Using our data, we develop a conceptual model of seasonal and hydrologic drivers of metal concentrations. The model can be modified for other systems aiding drinking water utilities and other water users in forecasting under what seasonal and hydrologic conditions that Mn and Fe concentrations in river systems are likely to be elevated.

show abstract

Evaluating Spatial Variability in Sediment and Phosphorus Concentration‐Discharge Relationships Using Bayesian Inference and Self‐Organizing Maps

Underwood

Rizzo

Schroth

et al. 2017

Water Resources Research

Self Cite

View full text Add to dashboard Cite

Given the variable biogeochemical, physical, and hydrological processes driving fluvial sediment and nutrient export, the water science and management communities need data‐driven methods to identify regions prone to production and transport under variable hydrometeorological conditions. We use Bayesian analysis to segment concentration‐discharge linear regression models for total suspended solids (TSS) and particulate and dissolved phosphorus (PP, DP) using 22 years of monitoring data from 18 Lake Champlain watersheds. Bayesian inference was leveraged to estimate segmented regression model parameters and identify threshold position. The identified threshold positions demonstrated a considerable range below and above the median discharge—which has been used previously as the default breakpoint in segmented regression models to discern differences between pre and post‐threshold export regimes. We then applied a Self‐Organizing Map (SOM), which partitioned the watersheds into clusters of TSS, PP, and DP export regimes using watershed characteristics, as well as Bayesian regression intercepts and slopes. A SOM defined two clusters of high‐flux basins, one where PP flux was predominantly episodic and hydrologically driven; and another in which the sediment and nutrient sourcing and mobilization were more bimodal, resulting from both hydrologic processes at post‐threshold discharges and reactive processes (e.g., nutrient cycling or lateral/vertical exchanges of fine sediment) at prethreshold discharges. A separate DP SOM defined two high‐flux clusters exhibiting a bimodal concentration‐discharge response, but driven by differing land use. Our novel framework shows promise as a tool with broad management application that provides insights into landscape drivers of riverine solute and sediment export.

show abstract

The mobility of phosphorus, iron, and manganese through the sediment–water continuum of a shallow eutrophic freshwater lake under stratified and mixed water-column conditions

Cited by 82 publications

References 45 publications

Winter weather and lake‐watershed physical configuration drive phosphorus, iron, and manganese dynamics in water and sediment of ice‐covered lakes

Winter weather and lake‐watershed physical configuration drive phosphorus, iron, and manganese dynamics in water and sediment of ice‐covered lakes

Effects of reservoir stratification and watershed hydrology on manganese and iron in a dam‐regulated river

Evaluating Spatial Variability in Sediment and Phosphorus Concentration‐Discharge Relationships Using Bayesian Inference and Self‐Organizing Maps

Contact Info

Product

Resources

About