TUBITAK 2232 (118C250): "Climate change effects on trophic structure and dynamics in saline and brackish water based on a space-for-time field sampling, controlled mesocosm experiments, paleoecology, remote sensing and modelling (CLIM-SALTLAKES)"

Funded by: TUBITAK, budget: 3,700,612 TL

Direction: Professor Erik Jeppesen (PI), Professor Meryem Beklioğlu, Professor Zuhal Akyürek, Asst. Professor Korhan Özkan

You can find the web site of project here.

Project Background

Global temperature and precipitation patterns have already been changing as a result of climate change, and the change in the semi-arid and Mediterranean climate zones are predicted to be particularly dramatic. A 25-30% decrease in precipitation and a parallel increase in evaporation in the Mediterranean region are expected by the end of the 21st century. Moreover, the land in drought is expected to double from 2000 to 2100. The magnitude of these changes and a consequent increase in salinity poses a major threat to the functioning and biodiversity of lakes. Novel studies that we have performed in North West China have shown drastic reductions in biodiversity (taxon richness), food chain length and average trophic position in the pelagial of the lakes with increased salinity. This indicates a loss of lake ecosystem functioning, and regime shifts when specific salinity thresholds are reached. However, the knowledge on the effect of warming on saline lakes is fragmented and far from at the level achieved for freshwater lakes.

Objectives

In this project, we aim at providing novel understanding of the structure and functioning of different types of saline/brackish lake ecosystems and their response to key stressors (warming, abstraction and external nutrient loading).

Hypothesis

We hypothesize that global warming and global change will

1) enhance the proportion of lakes that are saline,

2) enhance the variability in salinity,

3) make saline lakes more sensitive to other stressors such as excess nutrients and species invasions,

4) substantial decrease in species and trait richness of the organisms, and

5) consequently lead to major reduction in ecosystem functions and services.

Fig.1: Left: Freshwater lakes sampled in Turkey by METU. Mid and right two saline lakes (Acıgöl and Palas Tuzla) subjected to strong additional salinization due to water abstraction and climate warming.

Methodology

To test these hypotheses, we will use a multi-faceted approach, including

1) field observations through space for time substitute with snapshot samplings in different climate zones (in the short term, Turkey and Central Kazakhstan, in the long-term, inland saline lakes from Brazil to Tibet and a north-south gradient from Denmark to Turkey sampling)
2) analyses of changes in the past century by palaeoecological studies of sediment archives,
3) and on a decadal scale by analyzing existing contemporary time series and use of remote sensing,
4) establish highly equipped advanced mesocosm experimental facilities at Ankara and Mersin METU campus and run a series controlled mesocosms experiments, and
5) finally, by conducting modelling for prediction and syntheses.

We expect that METU within the three years project period will achieve an international leading role in the ecology of saline lakes in a climate change perspective, and using this platform and by attracting scientist to do or join studies in the new advanced experimental facilities, we expect that METU will become a true world leader in this field over the next 10 years period.