What is SALGA about?

Shallow lakes are an important natural resource in many densely populated areas in South America. And although temperate shallow lakes are among the best understood ecosystems in terms of stability and community dynamics this does not go for lakes at lower latitudes.

It has been shown that temperate lakes tend to be in either of two alternative stable states: a clear state dominated by submerged plants and high in biodiversity, and a turbid state dominated by phytoplankton which is much lower in biodiversity and has various water-quality problems that greatly reduce human utility.

Preliminary work suggests that shallow lakes may be very sensitive to climatic change. However, our ability to predict effects of expected climate change is limited severely by a lack of appropriate data on lower latitude lakes. The climate induced shifts part of SALGA focuses exactly on this topic.

The majority of the water quality problems are related to high nutrient loading, which promotes excessive phytoplankton development. However, the risk of algal problems depends also on the potential of algal control through the food chain, the so-called ‘trophic cascade’. Knowledge of the interactions in the food chain in lakes in temperate areas can help restore the lake to its clear water state by means of biomanipulation. The SALGA section trophic cascade aims to find out how climate, nutrient load, and the presence of vegetation interact to affect the functioning of the trophic cascade at lower latitude.

Click here for a time schedule of the sampling campaign.

Last updated: by Egbert van Nes. Please mail comments and questions to: Egbert.vanNes@wur.nl