Hypotheses ans Objetives

Hypotheses

– Increase in environmental unpredictability influences life-history traits related to dormancy in our model species, and by extension, to hololimnetic species living in time-varying environments.
– The interannual variability in the length of the growing season and the probability of false starts at the onset of the growing season select for bet-hedging strategies in traits related to the timing of breaking diapause at two levels, the proportion of hatching each cycle (bet-hedging between years) and the timing of hatching delay within each cycle (bet-hedging within years).
– The capacity to respond to unpredictability among and within years for the timing of diapause is more constrained in populations with a lower clonal diversity in origin, and this effect is more pronounced after several cycles of selection.
– Decline in adaptability after several cycles of evolution can be inferred from regions of the genome that are sensitive to selective pressure due to unpredictability.
– Signals of adaptability loss in the genome can be correlated with environmental traits in the studied natural waterbodies.
– The species diversity and composition of aquatic communities significantly varies i) according to a climate gradient between colder and warmer sites and ii) depending on the hydroperiod length of the water body (i.e. permanent to temporary). It is possible to define some groups of indicator species for different clusters of water bodies classified according to these two factors.
– Hatching experiments from egg banks of water bodies determine whether there are high differences from the active communities and if future communities affected by increased temperatures differ from present active ones and if they are resilient in their ecosystem functions. There are mismatches and reduced diversity from hatching experiments at temperatures warmer than those experienced under natural conditions.
– A positive relationship of the incidence of emergent pathogens such as the Nile virus in birds as reservoirs, with their incidence in mosquito vectors of the studied water bodies, would exist.
– Ecological niche models predict further expansions of freshwater exotic species and emerging pathogen vectors under the future scenarios of raising temperatures driven by global change
– The temperature and hydroperiod (and its predictability) are key factors for the species turnover among prokaryotic and eukaryotic aquatic communities.
– The relative incidence of pathogens and exotic species increase with increasing temperatures.
– A unidirectional response pattern to unpredictability arises for the studied communities.
– The rates of metabolic activities, such as those of the main carbon processes measured by gas exchanges, as well as of these and other biogeochemical pathways determined by metatranscriptomics, increase along the temperature gradient of the study sites.
– The hydroperiod length and its predictability influences the overall annual balances of the main biogeochemical activities of the C and other element cycles

 

Objectives

The general objective is to study the influence of factors relevant to climate change (temperature, hydroperiod length and variation, predictability) on the potential response (adaptability) of populations, communities and ecosystems in Mediterranean aquatic systems. Specific objectives are the following:

• Objective 1: (populations) To test the consequences of clonal diversity reduction, on fitness-related traits among populations of a model organism (the rotifer B. plicatilis) inhabiting water bodies of increasing unpredictability in the length of their hydroperiod.
• Objective 2: (communities) To evaluate the effect of climate-related limnological traits of lentic shallow water bodies (temperature, hydroperiod) on the diversity and composition of Mediterranean aquatic communities, with special emphasis on exotic species and pathogens.
• Objective 3. (ecosystems) To assess the differences in ecological functioning of Mediterranean wetland ecosystem given by differences in temperature and the hydrological pattern and their predictability.
• Objective 4. (integration and adaptation to climate change) To provide integrative insights to the authorities and the society to favour climate change adaptation in Mediterranean wetlands.