Sammanfattning

Eutrophication and anoxia are unresolved issues in many large waterbodies. Globally, management success has been inconsistent, highlighting the need to identify approaches which reliably improve water quality. We used a process-based model chain to quantify effectiveness of terrestrial nutrient control measures on in-lake nitrogen, phosphorus, chlorophyll and dissolved oxygen (DO) concentrations in Lake Simcoe, Canada. Across a baseline period of 2010-2016 hydrochemical outputs from catchment models INCA-N and INCA-P were used to drive the lake model PROTECH, which simulated water quality in the three main basins of the lake. Five terrestrial nutrient control strategies were evaluated. Effectiveness differed between catchments, and water quality responses to nutrient load reductions varied between deep and shallow lake basins. Nutrient load reductions were a significant driver of increased DO concentrations, however strategies which reduced tributary inflow had a greater impact on lake restoration, associated with changes in water temperature and chemistry. Importantly, when multiple strategies were implemented simultaneously, resultant large flow reductions induced warming throughout the water column. Negative impacts of lake warming on DO overwhelmed the positive effects of nutrient reduction, and limited the effectiveness of lake restoration strategies. This study indicates that rates of lake recovery may be accelerated through a coordinated management approach, which considers strategy interactions, and the potential for temperature change-induced physical and biological feedbacks. Identified impacts of flow and temperature on rates of lake recovery have implications for management sustainability under a changing climate. (C) 2018 The Authors. Published by Elsevier B.V.

Nyckelord

Eutrophication; Dissolved oxygen; Phosphorus; Limnology; Temperature; Management

Publicerad i

Science of the Total Environment
2019, Volym: 652, sidor: 382-397
Utgivare: ELSEVIER SCIENCE BV

SLU författare

• Futter, Martyn

  • Institutionen för vatten och miljö, Sveriges lantbruksuniversitet
    

Globala målen

SDG6 Säkerställa tillgången till och en hållbar förvaltning av vatten och sanitet för alla
SDG13 Vidta omedelbara åtgärder för att bekämpa klimatförändringarna och dess konsekvenser
SDG12 Säkerställa hållbara konsumtions- och produktionsmönster


UKÄ forskningsämne

Oceanografi, hydrologi, vattenresurser


Publikationens identifierare

DOI: https://doi.org/10.1016/j.scitotenv.2018.10.160

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/97745