Climate-related differences in the dominance of submerged macrophytes in shallow lakes

• Published in: Global change biology Vol. 15; no. 10; pp. 2503 - 2517
• Main Authors: KOSTEN, SARIAN, KAMARAINEN, AMY, JEPPESEN, ERIK, VAN NES, EGBERT H, PEETERS, EDWIN T.H.M, MAZZEO, NÉSTOR, SASS, LAURA, HAUXWELL, JENNIFER, HANSEL-WELCH, NICOLE, LAURIDSEN, TORBEN L, SØNDERGAARD, MARTIN, BACHMANN, ROGER W, LACEROT, GISSELL, SCHEFFER, MARTEN
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01-10-2009; Blackwell Publishing Ltd; Wiley-Blackwell
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Aquatic Ecology; aquatic macrophytes; aquatic plants; Aquatische ecologie; Biological and medical sciences; climate; Climate change; climatic zones; communities; Comparative studies; depth; diepte; Ecology; europa; Europe; eutrophic lakes; fish; fosfor; Fresh water ecosystems; Freshwater; Fundamental and applied biological sciences. Psychology; fytoplankton; General aspects; growth; klimaat; Lakes; logistic regression; logit analysis; meren; nitrogen; noord-amerika; North America; nutrient; Nutrients; phosphorus; phosphorus concentrations; phytoplankton; restoration; shallow lakes; South America; stikstof; submerged macrophytes; Synecology; temperature; temperatuur; troebelheid; turbidity; vegetatie; vegetation; voedingsstoffen; water quality; waterkwaliteit; waterplanten; zuid-amerika; South America; North America; Europe; America; Uruguay; USA, Florida; South America; Logistic regression; Climate; shallow lakes; Europe; submerged macrophytes; Lakes; Phosphorus; Aquatic plant; Nitrogen; Shallow water; North America
• ISSN: 1354-1013; 1365-2486
• DOI: 10.1111/j.1365-2486.2009.01969.x

It has been suggested that shallow lakes in warm climates have a higher probability of being turbid, rather than macrophyte dominated, compared with lakes in cooler climates, but little field evidence exists to evaluate this hypothesis. We analyzed data from 782 lake years in different climate zones in North America, South America, and Europe. We tested if systematic differences exist in the relationship between the abundance of submerged macrophytes and environmental factors such as lake depth and nutrient levels. In the pooled dataset the proportion of lakes with substantial submerged macrophyte coverage (> 30% of the lake area) decreased in a sigmoidal way with increasing total phosphorus (TP) concentration, falling most steeply between 0.05 and 0.2 mg L⁻¹. Substantial submerged macrophyte coverage was also rare in lakes with total nitrogen (TN) concentrations above 1-2 mg L⁻¹, except for lakes with very low TP concentrations where macrophytes remain abundant until higher TN concentrations. The deviance reduction of logistic regression models predicting macrophyte coverage from nutrients and water depth was generally low, and notably lowest in tropical and subtropical regions (Brazil, Uruguay, and Florida), suggesting that macrophyte coverage was strongly influenced by other factors. The maximum TP concentration allowing substantial submerged macrophyte coverage was clearly higher in cold regions with more frost days. This is in agreement with other studies which found a large influence of ice cover duration on shallow lakes' ecology through partial fish kills that may improve light conditions for submerged macrophytes by cascading effects on periphyton and phytoplankton. Our findings suggest that, in regions where climatic warming is projected to lead to fewer frost days, macrophyte cover will decrease unless the nutrient levels are lowered.