Dissertation in Evironmental Science, May 27: Pablo Urrutia-Cordero
Pablo Urrutia-Cordero (Department of Biology and CEC) is defending his thesis in Environmental Sciences, "Local adaptation of freshwaters to global environmental change - Putting food web theory into action".
When: Friday 27 May, 09.00
Where: Blue Hall, Ecology Building
Pablo about his research:
How will future climatic and environmental changes impact our freshwater ecosystems and how can we address undesired regional and global changes in the best way? Firstly, my PhD thesis deals with interactive effects of multiple environmental drivers expected to impact freshwater ecosystems simultaneously during the lifetime of the coming generation. Specifically, I use mesocosm experiments to study whether predicted global and regional trends in eutrophication, warming and brownification (increase of humic substances) will affect aquatic food web interactions and ecosystem functioning. Will we transgress threshold levels of drivers leading to abrupt changes in major ecosystem components or will those changes take place in a more gradual way? If so, which effective tools could be provided to avoid bad transitions as well as aid restoration of already degraded ecosystems?
In this context, I also work in a eutrophic lake that is subject to biomanipulation attempts (removal of planktivorous fish) aiming to improve the water quality. Here, I study how the increase, via trophic cascade, of natural zooplankton herbivores can be used as a tool to increase system stability as well as population control of toxic algal blooms. Moreover, I investigate major factors and mechanisms causing regime shifts in whole lake ecosystems, i.e., systems that change from clear water states dominated by macrophytes to turbid states with incidence of massive toxic algal proliferation.
Why Environmental Science?
My interest in environmental sciences is rooted during my youth at my home country, Spain. As a child, I grew up with the notion that freshwater resources are particularly scarce. This is not only due to droughts, but also as a result of intensive extractions for irrigation in agricultural fields and urbanization. Increasingly, Spanish groundwater and reservoirs are depleting, which is turning national policies toward seawater desalination to meet population water demands.
During my graduate studies in Environmental Sciences at the Autonomous University of Madrid (Spain) and Gothenburg University (Sweden), I came to realize that more effort is needed to improve the quality of available water resources for human and animal consumption. For example, warm and nutrient-rich-polluted water bodies are abundant in Spain and these are prone to host massive growths of blue-green algae (cyanobacteria) producing potent toxins to humans and other animal health. These "toxic cyanobacterial blooms" can therefore dramatically hamper human use of lakes, reservoirs and ponds. Despite these negative impacts, I found it fascinating how these toxic algae have evolved so many efficient physiological adaptations that allow them to spread and colonize not only water bodies, but also terrestrial ecosystems and extreme environments across the entire globe.
Later on, I enrolled on a 2-year European Master program focused on inland water quality assessment in Spain and Sweden. In 2012 I started my PhD studies at Lund University (Sweden). The topic of my PhD thesis was exactly what I was looking for, as it centered on investigating how current environmental changes that act on a global scale (e.g., climate warming and increased humic substances running off from the catchment) affect the growth of toxic cyanobacteria in freshwater ecosystems. In addition, the work was focused on finding out whether food web manipulations (i.e., removing benthic and plankton-feeding fish) could be used to increase the resilience of aquatic systems to their growth and explore their application in adaptation schemes to combat global environmental change.
Today I consider myself an environmental scientist with the primary aim of solving human-induced environmental problems. Modern human lifestyle and population growth are recognized as major drivers of current global-scale environmental change and we therefore have the responsibility and capacity to act in consequence to accommodate nature in the best sustainable way. My interests are now broader and include issues regarding water pollution and overexploitation, biodiversity loss and the sustainability of natural ecosystems as units of ecosystem services. For example, I am soon starting a new project to look into the effects of water resource degradation on terrestrial biodiversity and pollination services in the agricultural landscape. For that purpose, I believe that combining mechanistic experiments with field observational studies is a powerful tool to aid understanding on the consequences of environmental changes, as well as to find solutions to balance both nature and human welfare. I am also very keen to collaborate with other biologists, environmental, economical and social scientists to address related interdisciplinary questions.