Is it possible to prevent the future impact of new occurrences of the Red Tide phenomena?

Researchers from the Centre for Biotechnology and Bioengineering (CeBiB) and the Centre for Mathematical Modelling (both at the University of Chile), and scientists from the Centre i-Mar at the University of Los Lagos and the Institute for Fishing Promotion (IFOP), recently constituted a multidisciplinary team. This group looks for the development of a biological-mathematical model to understand the dynamics of the Red Tide phenomena to create a model that allows predicting the evolution of such events.

A multidisciplinary team of ecologists, marine biologists and mathematicians, along with experts from other disciplines, was formed a couple of months ago to develop a mathematical model that allows understanding the dynamics of the Red Tide occurrences and to develop a computer based application to predict the evolution of such events.

In this initiative researchers from the Centre for Biotechnology and Bioengineering (CeBiB) and the Centre for Mathematical Modelling CMM (both at the Faculty of Physical and Mathematical Sciences in the University of Chile and with funding from CONICYT Associative Research Program) are participating and scientists from the Centre i-Mar at the University of Los Lagos and the Institute for Fishing Promotion (IFOP), at Puerto Montt.

The group will address one of the most difficult questions about microalgae harmful bloom: is it possible to predict their occurrence?

Alejandro Buschmann, principal researcher at CeBiB and i-Mar, says that “although it is as complex as predicting the weather, it is possible. It requires a system of ocean sensors (buoys) to monitor the marine environment and to detect changes in temperature, light, currents and nutrients in the water. By using mathematical models, it could be possible to analyze the possibility of predicting these events and test the system in time. Now, this approach requires investment and funding to keep it operative”.

The development of this potential mathematical model is described by Carlos Conca, Chilean National Science Award, as a major challenge. Conca, researcher at CeBiB and CMM, says, “the first precaution is to realize that this research is just beginning and that this topic is an extremely complex phenomena that involves many physical and biological variables. It is a major challenge not only predicting a blooming event, but its evolution”.

Professor Carlos Conca

Professor Carlos Conca, from CeBiB and CMM, Chilean National Science Award.

Observation system: the key element

Conca and Buschmann agree in the complexity of the phenomena and they compare it to meteorological prediction: “Forty years ago it was impossible to predict the weather. Today, thanks to the development of mathematical models, their computerization and the vast amount of data available, predictions are reliable in a scale of hours. This was possible not only because of the mathematical modelling and computerization work, but also because of the development of a data network composed of satellites and meteorological stations, among other systems”.

The data, consisting in readings and observations- it is a key component of a potential model.

Daniel Varela, ecologist, director of the centre i-Mar and researcher at CeBiB, explains that the data registry has been implemented in other countries with different success rates: “In the United States, for instance, a system was developed for the Atlantic coast and it works perfectly, very close to reality. With it they were able to develop predictive strategies for algal bloom”.

Algal blooms are a recurrent phenomenon: the events occur after a certain amount of years and they have shown to be moving from the south of Chile to the coast of Los Lagos county. “This region is more inhabited and, therefore, the impact of the event is deeper”, according to Buschmann.

Is it possible to prevent the impact?

“In parallel with the development of strategies to face the crisis, it is clear that Chile must invest in a preventive system: it is urgent to have a study of nitrate levels in our marine basins across urban, agrarian and livestock regions”, explains Buschmann. With this study, we could have an evaluation of the current state of the coastal water in the south of Chile: “Today we don’t have this information and I think it is urgent. We must have evidence of the impact that human activities are having in our marine ecosystems”.

In addition, we must understand the impact of changing variables associated to climate change (such as temperature and light regimes) and acidification on the quality of the water. With this information, we should be able to analyze the potential impact on aquaculture and fishing.

Without a system that provides data permanently, mathematical modeling is comparable to children toys, says Carlos Conca. “They only acquire a real predictive capability once they receive a vast amount of qualitative and quantitative data”, explain Marc Dambrine and Bénédicte Puig, mathematicians from France currently working in Chile in this project.

For Red Tide, Carlos Conca describes the variables they need to know: those related to the sea (temperature, salinity, light, oxygen concentration, currents, etc.) and the nutrient and gametes concentration related to Alexandrium catanella, the microalgae specie most known for its negative effects when it blooms. “Currently, we only have access to partial data obtained abroad, from a variety of catanella that blooms in the Gulf of Maine, New England (USA)”, explains the mathematician.

Conca is emphatic to state that “without the development of a network of monitors and the generation of data, this work could remain in the academic field: there will be papers, but it will not be of direct utility for society in the short term. This question is more a requirement for those in charge of taking the decisions”, he concludes.