In order to face challenges in the future, scientists are investigating the Earth’s past

A joint project between Brazilian and French scientists attempts to reconstruct the stages of evolution based on geological sediments analysis; that and other initiatives that look at the challenges of the period known as the Anthropocene were presented at FAPESP Week France.

By Heitor Shimizu, from Paris  |  Agência FAPESP – The need to find alternatives for the future has motivated a group of Brazilian and French researchers to look more than 500 million years into the past, in an attempt to understand the many stages in the evolution of terrestrial life.

The study, supported by FAPESP, was presented on November 25th by Magali Ader, a professor at the Institut de Physique du Globe de Paris, during FAPESP Week France.

“Facing the challenges of the Anthropocene [a term used by some scientists to describe the current period in the history of Planet Earth] will require human societies to adjust to climate change and find new energy sources. Some of these sources could be hydrogen, water, hydrocarbons, or rare elements and, for this, it is important to understand the Earth system well,” said the researcher.

The focus of the line of research conducted by Ader is on geological sediments in Brazil. The investigation involves the collaboration of Professor Ricardo Trindade’s group, at the Institute of Astronomy, Geophysics, and Atmospheric Sciences of the University of São Paulo (IAG-USP).

The Thematic Project brings together more than 30 scientists from Brazil and France. The group’s aim is to study the Earth system and the evolution of life during the Neoproterozoic era (between 1 billion and 541 million years ago), a period of significant changes in the planet’s composition and dynamic, with the appearance of complex lifeforms and the shaping of continents, as well as important climate variations.

“It’s very important to be able to work with Professor Trindade’s group, as we have complementary research specialties. In this work, we need to include scientists from different areas and that requires substantial funding. There aren’t many agencies in the world willing to support a project like this and, thankfully, FAPESP is one of them. Because of that, Brazil is one of the few places where such a project could be conducted,” Ader told Agência FAPESP.

The greenhouse effect

Climate change caused by the emission of greenhouse gases, such as carbon dioxide (CO₂), nitrous oxide (N₂O) and ozone (O₃), is one of the challenges humanity faces in the period known as the Anthropocene.

The emissions resulting from sugarcane production in the State of São Paulo was the topic addressed by Janaina Braga do Carmo, a professor at the Federal University of São Carlos – UFSCar’s Sciences and Technologies for Sustainability Center, at FAPESP Week France.

“Brazil is the biggest producer of sugarcane for the production of ethanol [renewable energy] and sugar in the world. Soil management, the use of nitrogen fertilizers, and waste from ethanol production, as well as vinasse, filter cake, and post-harvest hay, can compromise the sustainability of cultivations, increasing greenhouse gas emissions,” she said.

According to Carmo, another important issue is the expansion of sugarcane into grasslands, characterizing a change in land use – which can alter the dynamic and balance of greenhouse gas emissions in Brazilian agriculture.

“We’re seeking to understand the greenhouse gas emissions during the process of converting grasslands into sugarcane plantations, considering normal management practices. The aim is to propose management alternatives capable of reducing emissions and increasing the sustainability of the production system,” she said.

The research is being conducted within the scope of a Thematic Project under the aegis of FAPESP Research Program on Global Climate Change (RPGCC), coordinated by Professor Luiz Antonio Martinelli, of the Center for Nuclear Energy in Agriculture (CENA) at USP.

“After the first year of measures and analyses, we verified that the emissions resulting from sugarcane cultivation are greater than those that existed under grassland conditions. However, we still need to evaluate the nitrogen source used in the experiment,” Braga told Agência FAPESP.

Mitigation of gases

The impact of the soil microbiota on the mitigation of greenhouse gases in tropical forests was the topic of a lecture given by Tsai Siu Mui, a professor and vice-director at CENA-USP.

As the researcher reiterated, greenhouse gases retain the thermal energy reflected by the Earth’s surface. However, in soils of tropical forests, such as the Amazon, elements such as methane and nitrous oxide are actively recycled through biogeochemical processes.

“This was demonstrated by measuring subterranean microbial activities together with gas flows,” said Tsai, who has been coordinating a study within the scope of the FAPESP Research Program on Biodiversity Characterization, Conservation, Restoration and Sustainable Use (BIOTA-FAPESP).

According to the researcher, microorganisms coordinate the ecological processes on which life depends, but little is known about their biodiversity. The research project she coordinates combines advances in nucleic acid sequencing and ecosystem biochemistry to investigate the control of the methane cycle throughout gradients of soil use in tropical forests.

“To answer these questions, we’re studying the genetic, phylogenetic, and functional dimensions of the biodiversity of bacteria and archaea in two fragments of tropical forest threatened by development: one in the East Amazon, in [the state of] Rondônia, and a reserve in the West Amazon close to Santarém, in [the state of] Pará,” she said.

“These forests have a range of ecosystems, soil characteristics, and soil use history. We’ve already observed a reduction in nitrous oxide emissions when the natural fauna is freely present in the forest,” she said.

The session also included a presentation by François Moriconi, from the Université Paris Diderot, who was a visiting researcher at the São Paulo State University (UNESP) in Presidente Prudente and spoke about his collaboration with the Research Group for the Production of Space and Regional Redefinitions (GAsPERR).

The FAPESP Week France symposium took place between November 21st and 27th, thanks to a partnership between FAPESP and the universities of Lyon and Paris, both in France. Read other news about the event at www.fapesp.br/week2019/france/.