Lake responses following lanthanum-modified bentonite clay (Phoslock®) application: an analysis of water column lanthanum data from 16 case study lakes

Autor: Ana T. Castro-Castellon, Miquel Lürling, Max M. Gibbs, Darren Sleep, Frank van Oosterhout, Bryan M. Spears, Sebastian Meis, Said Yasseri, Claire McDonald, John McIntosh
Přispěvatelé: Aquatic Ecology (AqE)
Rok vydání: 2013
Předmět:
Aquatic Ecology and Water Quality Management
ecological restoration
ecological risk assessment
Alkalinity
netherlands
Water column
terugwinning
aquatic ecology
ecologisch herstel
lakes
Lanthanum
remediatie
Phoslock
phosphorus
Waste Management and Disposal
Water Science and Technology
lanthaan
Ecological Modeling
shallow lakes
unintended consequences
loch leven
bentoniet
Pollution
control methods
eutrophication
Biodegradation
Environmental
quality
international
Bentonite
bestrijdingsmethoden
fosfor
lanthanum
Environmental Engineering
restoration
groundwater quality
meren
chemistry.chemical_element
ecologische risicoschatting
oppervlaktewaterkwaliteit
Ecology and Environment
phosphorus-binding clay
Bottom water
recovery
remediation
Civil and Structural Engineering
Hydrology
WIMEK
bentonite
Phosphorus
removal
aquatische ecologie
Water
daphnia
Aquatische Ecologie en Waterkwaliteitsbeheer
grondwaterkwaliteit
Lakes
chemistry
sediment
Environmental science
Water quality
Eutrophication
surface water quality
eutrofiëring
Zdroj: Water Research, 47(15), 5930-5942. Elsevier B.V.
Water Research, 47(15), 5930-5942
Water Research 47 (2013) 15
ISSN: 1879-2448
0043-1354
Popis: Phoslock(®) is a lanthanum (La) modified bentonite clay that is being increasingly used as a geo-engineering tool for the control of legacy phosphorus (P) release from lake bed sediments to overlying waters. This study investigates the potential for negative ecological impacts from elevated La concentrations associated with the use of Phoslock(®) across 16 case study lakes. Impact-recovery trajectories associated with total lanthanum (TLa) and filterable La (FLa) concentrations in surface and bottom waters were quantified over a period of up to 60 months following Phoslock(®) application. Both surface and bottom water TLa and FLa concentrations were0.001 mg L(-1) in all lakes prior to the application of Phoslock(®). The effects of Phoslock(®) application were evident in the post-application maximum TLa and FLa concentrations reported for surface waters between 0.026 mg L(-1)-2.30 mg L(-1) and 0.002 mg L(-1) to 0.14 mg L(-1), respectively. Results of generalised additive modelling indicated that recovery trajectories for TLa and FLa in surface and bottom waters in lakes were represented by 2nd order decay relationships, with time, and that recovery reached an end-point between 3 and 12 months post-application. Recovery in bottom water was slower (11-12 months) than surface waters (3-8 months), most probably as a result of variation in physicochemical conditions of the receiving waters and associated effects on product settling rates and processes relating to the disturbance of bed sediments. CHEAQS PRO modelling was also undertaken on 11 of the treated lakes in order to predict concentrations of La(3+) ions and the potential for negative ecological impacts. This modelling indicated that the concentrations of La(3+) ions will be very low (0.0004 mg L(-1)) in lakes of moderately low to high alkalinity (0.8 mEq L(-1)), but higher (up to 0.12 mg L(-1)) in lakes characterised by very low alkalinity. The effects of elevated La(3+) concentrations following Phoslock(®) applications in lakes of very low alkalinity requires further evaluation. The implications for the use of Phoslock(®) in eutrophication management are discussed.
Databáze: OpenAIRE
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