Latin America: study proposes monitoring marine coastal ecosystems

Priority areas related to the impacts of environmental and climate change in habitats deserve more investigation.

By Elton Alisson

Agência FAPESP – Researchers from Latin American countries—including Brazil—and European countries have published an article in Global Change Biology in which they outline a series of recommendations for development of a scientific and political agenda concerning the impacts of environmental and global and regional climate changes on marine coastal ecosystems in Latin America.

According to the authors of the article, the region contains a large variety of benthic habitats (formed by organisms that live in marine substrates), many of which possess great biodiversity and should be the main priorities (hotspots) for conservation actions. Among these habitats are enormous layers of rhodoliths (reefs made of calcareous red algae), as well as mangroves, marine grass banks and coral reefs in the Tropical Atlantic Ocean with large numbers of endemic species.

These marine habitats are extremely important for the residents of the coastal areas of Latin America, who depend on the environmental quality of the sea for economic activities such as fishing and tourism.

According to the authors of the study, these marine habitats must be protected, particularly at a time of rapid environmental and climatic change and given social problems such as uncontrolled urbanization in the region, which adds to pressures such as aquatic pollution, overfishing and loss and fragmentation of habitats.

“There are several groups that study the impact of climate change, especially in Brazil. But this does not occur on the same scale in other countries in South and Central America,” commented Alexander Turra, professor at the Universidade de São Paulo’s Oceanography Institute and the first author of the article.

Turra currently coordinates the Monitoring Network of Coastal Benthic Habitats (ReBentos), funded by FAPESP under the auspices of an agreement with the National Council of Scientific and Technological Development (CNPq) for consolidation of the National Research System on Biodiversity.

The objective of the project, launched at the beginning of 2011 and linked to the Climate Network’s Coastal Zones Sub-Network (MCT) and the National Science and Technology Institute on Climate Change (INCT-MC), , is to create an integrated network of studies of benthic habitats on the Brazilian coast to detect the effects of regional and global environmental change on these habitats and initiate collection of a historical data series on benthic biodiversity on the Brazilian coast.

“The idea is to establish monitoring sites along the Brazilian coast to be observed over time,” explained Turra. The network consists of 120 benthologists from 14 Brazilian states who are focused on studying the impacts of environmental and climate change on coastal marine habitats.

In the assessment of Turra and the other authors of the article, ReBentos and similar networks in Latin America, such as the South American Research Group in Coastal Ecosystems (Sarce), represent continuous monitoring initiatives for coastal ecosystem habitats that should be replicated in other countries throughout the region to fill critical gaps in the body of knowledge concerning the impacts of climate change.

“The systematic application of standardized monitoring protocols, adapted to each habitat, scale, level of organization and different oceanographic conditions is essential to document the degradation, fragmentation or loss of coastal marine habitats,” noted one of the authors of the study.

“These experimental and proven actions must be spread to other countries in the region through ongoing local projects and a an open access database must be built with information about the current state and forecasts for changes in habitats on the local, regional and global level,” he indicated.

Priority areas

According to the authors of the study, the initial efforts at monitoring coastal habitats should be centralized in locations that are suffering immediate prejudicial pressure, such as coral reefs in the Caribbean, where there are indications of bleaching (death of the polyps responsible for forming the reef) associated with rising ocean temperatures.

Acidification (increased acidity indicated by a reduction in the pH level) of oceans threatens to not only degrade the world’s largest layers of rhodoliths, found on the Brazilian coast, but also reduce the capacity of marine organisms, such as crustaceans, clams and oysters, to produce shells, putting at risk aquaculture and the food security of river-dwelling communities, according to the authors.

The researchers stressed, however, that studies are still needed to prove the associations of these environmental problems with climate change. “We discuss these questions theoretically, because we still don’t have much baseline data on the marine ecosystems to understand how they were before and document the changes they have undergone. That’s why we need to monitor these organisms for a long time,” said Turra.

Another concern among specialists is the impact of extreme climate events—which will tend to be more frequent with global climate change—on marine ecosystems (such as mangroves) that play important roles in protecting coastlines, which are subject to tides and the energy of waves.

The researchers call attention to the need for a warning system for extreme climate events in coastal communities, which face greater exposure to inclement weather than inland communities.

“The increased frequency and magnitude of storms associated with the elevation of wave energy could compromise coastlines and impact buildings and other constructions. One example of this, although not proven to be associated with climate change, were the impacts felt by the Port of Itajaí in Santa Catarina in 2008,” offered Turra.

Contribution to AR5

The article published in Global Change Biology is the result of the workshop “Evaluating the sensitivity of Central and South American benthic communities to global environmental change,” held at the end of April 2012 in Ilhabela, São Paulo. The workshop addressed how Latin American countries should prepare for global climate change.

The workshop was organized by Flávio Berchez, who is a professor in the Universidade de São Paulo’s Botany Department within the Biosciences Institute, a member of ReBentos and one of the authors of the article, along with Turra and other researchers. The event brought together scientists from ten Latin American and three European countries.

“Specialists on marine ecosystems underscore Latin America’s lack of research with significant approaches, such as those highlighted in the article, to reach conclusions on the impact of climate change on these ecosystems, relative to other countries,” explained Marcos Silveira Buckeridge, a professor in the Universidade de São Paulo’s Botany Department within the Biosciences Institute. “Because of this, I suggested the workshop and that the event resulted in an article compiling this information to report it to the IPCC.”

Buckeridge is one of the commentators for chapter 27 of the Intergovernmental Panel on Climate Change (IPCC) report—AR5—which is slated for publication in 2014. The chapter addresses the effects of climate change in Latin America.

According to Buckeridge, the article will be submitted for evaluation by the commentators for chapter 27 at the next meeting of the group of scientists, next July in Slovenia.

The article “Global environmental changes: setting priorities for Latin American coastal habitats (doi: 10.1111/ gcb.12186),” by Alexander Turra and others, can be read at onlinelibrary.wiley.com/doi/10.1111/gcb.12186/abstract.