Nace El Observatorio del Besòs: un proyecto de seguimiento de la calidad de los sistemas fluviales de la cuenca

La Universitat Autònoma de Barcelona (UAB) a través del Institut de Ciència i Tecnologia Ambientals (ICTA-UAB), y el Consorci Besòs Tordera evaluarán el estado de calidad a largo plazo de la cuenca del Besòs gracias a la creación de la Observatorio del Besòs.

Shift in large-scale Atlantic circulation causes lower-oxygen water to invade Canada's Gulf of St. Lawrence

The Gulf of St. Lawrence has warmed and lost oxygen faster than almost anywhere else in the global oceans.

Climate Change Modifies the Composition of Reefs

Corals devastated by climate change are being replaced naturally by other species such as gorgonians, which are less efficient in acting as a carbon sink.

ICTA-UAB launches the first master’s Degree in “Political Ecology. Degrowth and Environmental Justice”

The Institute of Environmental Science and Technology (ICTA-UAB) launches the master’s Degree in “Political Ecology.

Pioneering study analyses the effects of forests on human health

A group of volunteers have participated in an experimental study conducted by the ICTA-UAB to analyse the potential health benefits of forests.

Marine Litter on Mediterranean Beaches Triples in Summer

The Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB) analyses and quantifies the waste generated by tourists in eight islands of the Mediterranean as part of the European BLUEISLANDS project.

Mapping the Urban Vitality of Barcelona

Researchers at the UAB have mapped Barcelona and and 9 surrounding towns using a new methodology based on urbanism activist Jane Jacobs' ideas on how cities should be configured to become vital spaces: 25% of the area is classified as having high vitality.

Agricultural intensification not a “blueprint” for sustainable development

Social and ecological results of increased agricultural intensification are not as positive as expected.

Green urban planning must consider social equity criteria

Cities that do not include social equity criteria into their political strategies to make their urban environment greener and more ecological will not achieve long-term sustainability and risk creating green enclaves only for the social elite.

The ICTA-UAB alerts of a new invasive Asian beetle pest in Catalonia that kills mulberry trees

A study by researcher of the ICTA-UAB and the Department of Agriculture Víctor Sarto i Monteys has identified in the province of Barcelona the presence of a species from Asia that could spread through Europe.

More than 120 ICTA-UAB researchers addressed environmental challenges at a symposium, especially those arising from global and...

The Institut of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB) organized its 1st Spring Symposium with the aim of addressing some of the main environmental and sustainability challenges.

Low-carbon energy transition requires more renewables than previously thought

A new study by ICTA-UAB analyzes the impacts on lifestyles of substituting fossil fuels for cleaner energies.

Are Farmers Who Belong to Local User Associations Better Adapted to Climate Change?

Droughts, floods and high temperatures derived from climate change are not the only threats that farmers with irrigated crops must face.

Climate Change Threatens World's Largest Seagrass Carbon Stores

Shark Bay seagrass carbon storage hotspot suffers alarming losses after a devastating marine heat wave, according to a study led by ICTA-UAB researchers.

Amazon's indigenous people hunt animals feeding in areas contaminated by oil spills

A study by the ICTA-UAB and the UAB Department of Animal Health and Anatomy demonstrates that the main species hunted by the indigenous popoulations of the Peruvian Amazon ingest water and soil contaminated with hidrocarbons and heavy metals.

The new Planttes app warns of allergy risks in different urban areas

The Planttes application is a citizen science project which aims to encourage people to identify and locate on a map the existence of allergy-causing plants and indicate their phenological state.

New Project to Link Extreme Weather Events, Atmospheric Biodiversity and Human Health

A new ICTA-UAB project led by researcher Jordina Belmonte will study the effects of extreme meteorological events on the biological biodiversity present in the atmosphere in order to predict changes in the environment and possible affectations on human health.

ICTA-UAB’s success: five ERC grants in two years

The Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB) has been awarded five European Research Council (ERC) grants in two years, which is about ten per cent of all ERC grants arriving in Catalonia over the period from the end of 2015 to the end of 2017.

New ICTA-UAB 'Welcome Guide'

The new ICTA-UAB 'Welcome Guide' it is at your disposal now. With this document, we aim to help you discover the basics of the PhD programme, ICTA-UAB’s structure, etc.
News
Climate Change Modifies the Composition of Reefs

Date: 2018-09-20

Climate Change Modifies the Composition of Reefs


Corals devastated by climate change are being replaced naturally by other species such as gorgonians, which are less efficient in acting as a carbon sink.

A study by the ICTA-UAB analyzes for the first time why gorgonians are more resistant than corals to human impacts and global climate change.

The gorgonians are replacing scleractinian corals that are disappearing from marine ecosystems due to human impact and global climate change. This is the result of a study carried out by researcher of the Institute of Science and Environmental Technology of the Universitat Autònoma de Barcelona (UAB) Sergio Rossi, which analyzes the reason why the gorgonians (or octocorals) are proving to be one of the "winning" species in this transition process triggered by the spiraling death rates and degradation of corals in the deep sea and reefs.

It is estimated that after the last El Niño event (2015-2016), 50% of Australia's coral reefs are no longer functional: corals have died or been severely damaged. Climate change is eroding at all levels the most complex systems, such as reefs created by scleractinian corals, which are efficient animals that capture light through their symbionts (microscopic algae) to nourish themselves and build "stone". That same "stone" (the hard part of the coral, formed by calcium carbonate) is partly responsible for the high rate of algae photosynthesis, which supply up to 95% of the nutrients the animal needs to live.

"What is going on? Although the light may remain fairly constant, the sea temperature has risen", explains Rossi. The higher the temperatures, the more acceleration of the metabolic processes related to the photosynthetic process, to the extent that toxic molecules are created. The excess toxicity caused by the algae bothers the coral ... or the algae itself, it is not clear. What is clear is that when the temperature is too high, the algae simply leave the coral. This process is known as bleaching. And without algae, with only 5-15% of nutrients, the coral dies.

Given this situation, the gorgonians (and sponges) are replacing the dead coral to a great extent. The study, which was recently published in the journal Scientific Reports, aims to understand the coral reefs’ functioning in order to foresee their future. To that end, it compares for the first time the photosynthetic efficiency in nine Caribbean gorgonians, one of the most affected places by the transition from a healthy coral reef to one dominated by different species (not only due to climate change). The study shows that the photosynthetic efficiency has to do with the morphology of the organisms -of the gorgonians in question- which have more food (trophic) flexibility with respect to the existing resources than the scleractinian corals. These data allow us better to understand why octocorals seem to have an advantage in transition processes with respect to scleractinians, "although there are still many questions to be answered in order to understand what the future underwater landscape will be in tropical zones of the entire world".

However, according to the researcher, the replacement of corals by gorgonians is not entirely satisfactory. Although the gorgonians are more flexible to changes and adapt better, they store and retain less amount of carbon from the atmosphere, and their structures do not form reefs such as hard corals, nor are they more resistant to hurricanes. According to Rossi, "99% of the energy of the waves reaching the coastline during a hurricane is absorbed by coral reefs". Therefore, the study concludes that the disappearance of these reefs and other complex and long-lived biogenic structures only accelerates the degradation process of the entire planet.

Article:
Rossi S., Schubert N., Brown D., Oliveira Soares M., Grosso V., Rangel-Huerta E., Maldonado E. (2018). “Linking host morphology and symbiont performance in octocorals”. Scientific Reports 8: 12823 https://www.nature.com/articles/s41598-018-31262-3#article-info

ICTA's Activities