Can the effects of human activity on marine ecosystems be irreversible?

Knowing the problems that affect marine ecosystems around the world is one of the necessary actions to provide tools and early solutions in order to achieve adaptation to global climate change. In addition, protecting the biodiversity of the sea is a fundamental aspect of the three pillars of sustainable development -economic, social and environmental-, which maintains the healthy functioning of the planet, according to the UN.

Within this framework, an international investigation in which two scientists from the National Council for Scientific and Technical Research (CONICET) of Argentina participated, analyzed and identified the main problems that will affect marine ecosystems in the next decade.

The study, published in the academic journal Nature Ecology & Evolution, seeks to highlight environmental problems related to the ocean that do not have investment and incentives for research despite the fact that they will play a key role in the next decade due to their impact on the marine diversity.

Among the most outstanding issues are forest fires, the use of scientific devices for research in marine environments, the migration of aquatic species, coastal darkening, the increase in the toxicity of polluting metals due to ocean acidification, the possible exploitation of marine collagen of industrial interest, the extraction of lithium in deep sea waters and the construction of floating cities due to the rise in sea level.

Knowing the problems that affect marine ecosystems around the world is of vital importance. (Photo: courtesy of Alberto Piola, CONICET researcher at the Naval Hydrography Service, who also participated in the study)

These are issues that require in-depth examination and funding to do so, as highlighted, in dialogue with the CTyS-UNLaM Agency, Irene Schloss, CONICET researcher at the Austral Center for Scientific Research (CADIC-CONICET) and the Antarctic Institute Argentinian. With this research, Schloss and her colleagues wanted to bring these issues to light and warn that, if they are not addressed properly, the seriousness of various problems can increase, until some of them become practically irreversible in the near future.

For this international collaborative work, Schloss was invited, along with 30 other researchers from around the world, to identify the critical points that require more visibility. “On behalf of Argentina, with Alberto Piola, CONICET researcher at the Naval Hydrography Service, we think about these issues that will be important in the next decade, with a focus on our region,” the specialist mentioned.

Argentina and Latin America: among the areas most affected by coastal garbage

The fact that the study had the presence of two Argentines is not a minor detail: it meant the possibility of examining local problems, such as the darkening of the coast due to urban solid waste that, from the cities or due to excess fertilizers, ends up as garbage in the ocean and prevent good light from reaching the microalgae and macroalgae to carry out photosynthesis.

“Microalgae and macroalgae are what we call primary producers of food webs, that is, they are the base from which the rest of the food web of these organisms feeds. In order for plants to photosynthesise, light must reach them adequately. If we darken the water due to pollutants, this process is altered”, explained Schloss.

“This triggers several consequences: regarding the food web, whether or not the herbivorous organisms that feed on these marine plants will have enough food. But, in parallel, the fact that they cannot carry out the process of photosynthesis implies that less oxygen is released and, therefore, less carbon dioxide is sequestered, something that is essential to contribute naturally to the mitigation of global climate change,” he emphasized. the investigator.

Future of biodiversity: species that migrate

Another of the issues addressed in the list is the migration of species in different areas of the planet. “If the temperature increases in the middle zones of the globe, the organisms that are adapted to colder temperatures have to migrate south or north, depending on the hemisphere they inhabit; that is, they will move towards one of the poles to find a suitable temperature for their metabolism”, stated Schloss.

According to the specialist, the main areas of conflict for biodiversity are found on the two extremes at the equator and at the poles. “The increase in temperature in the equatorial line, the coastal zone and the tropics is somewhat more recent and they are experiencing records that have never before been taken into account in the matter of study.”

In this sense, he continued: “The serious thing is that there will come a time when the species will not find environments with the right temperature, because the global temperature will have increased and it will no longer be what they need to survive. The climatic conditions become extreme for these organisms.”

Sustainable marine constructions?

Floating hotels, self-sustaining buildings, glass walls under the sea, are some of the tourist proposals and paradisiacal attractions “of the future”. However, how do these constructions affect bodies of water? It is another of the points discussed in the work.

As an example, the biologist pointed to the case of the waters of the countries of the Arabian Peninsula: “It is very common to see aerial photos of the infrastructures on the sea. They are directly big cities and will definitely have an impact on the environment.” (Source: Agustina Lima / CTyS-UNLaM Agency)