Nav: Home

Scientists identify plant that flowers in Brazilian savanna one day after fire

June 18, 2019

Plants in the Brazilian savanna, the Cerrado, have evolved to deal with fire. When fire is used intelligently as part of a carefully planned land management method, it is indispensable to the conservation of this superb ecosystem, the world's most biodiverse savanna. Two months suffice for the Cerrado to burst into flower after a fire (read more at agencia.fapesp.br/26064 and agencia.fapesp.br/26542).

The study "From ashes to flowers: a savanna sedge initiates flowers 24 h after fire", published recently in the journal Ecology, confirms this observation.

"The species is Bulbostylis paradoxa, a sedge [perennial herb similar to rushes and grasses] belonging to the family Cyperaceae," Alessandra Fidelis, first author of the article, told. "Its common name in Brazil is cabelo-de-índio ['Amerindian hair']."

Fidelis is a professor at São Paulo State University (UNESP) in Rio Claro, Brazil, and conducted the study with support from São Paulo Research Foundation - FAPESP as part of the project "How does the fire season affect Cerrado vegetation?".

The Cerrado is a unique type of savanna. Its capacity to grow back and flower after burning is a key difference in comparison to African and Australian savannas.

This had already been reported in the nineteenth and early twentieth centuries by naturalists who visited Brazil, such as French botanist Augustin de Saint-Hilaire (1779-1853) and Danish plant ecologist Eugen Warming (1841-1924).

Leopoldo Magno Coutinho (1934-2016), a professor at the University of São Paulo (USP), focused on it in his habilitation.

Fidelis has been studying postfire regeneration of the Cerrado since 2009, but in this study, she was struck by the speed with which B. paradoxa flowers after being completely charred in a wildfire. The article is indeed a first in this respect. "It's the only event of its kind described worldwide to date," she said.

B. paradoxa is distributed throughout South America and is found from Venezuela to the south of the continent. It flowers on a significant scale only after fires. "In our experiments with burning as a careful management practice, we found that plants of this species reduced to carbonized stumps began exhibiting white spots 24 hours after the fire. These spots were incipient inflorescences," Fidelis recalled.

"In little more than a week, the flowers were fully formed and ready for pollination. The speed of this response is a significant advantage for the plant, enabling it to flower, fructify and disperse windborne seeds in the open, with the soil uncovered and without barriers or competitors. Only 40 days after a fire, it's very hard to find seeds because they've dispersed."

More generally, the abundant seeds available after fires in the Cerrado are an important resource for predators, such as ants and birds. Resprouting leaves are tender and palatable to large mammals, such as deer and cattle.

Burning is a problem when it results from arson or uncontrolled wildfires that spread disastrously owing to a buildup of combustible material after years without properly managed burning.

"The Cerrado has evolved through fire," Fidelis said. "Its vegetation regenerates easily. Species that did not occur before a fire may appear in certain areas. The animals may suffer losses, however, as many of them are trapped in fires. It is crucial to bear in mind that the Cerrado contains gallery forest, valley forest and palm marshes, where fire-sensitive species may fail to recover after a major burning. Hence, careful fire management is important. Preventive burning at the right time, with total area zoning and a rotating fire schedule for demarcated patches, is the best defense against disasters due to uncontrolled wildfire."

Expansion of the agricultural frontier, with large-scale monocultures and the intensive use of machinery and herbicides, leaving the soil completely clear and subject to invasion by signalgrass and molasses grass, is currently the main threat to the Cerrado's survival. Improper use of fire is the next most important threat. Together, these two factors endanger the continued existence of the entire ecosystem.

Some of Brazil's most important rivers originate in the Cerrado, including the Xingu, Tocantins, Araguaia, São Francisco, Parnaíba, Gurupi, Jequitinhonha, Paraná and Paraguay rivers. In addition to the irreparable loss of biodiversity, destruction of the Cerrado jeopardizes the basins of these rivers as a major source of fresh water and hydropower potential.
-end-
About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at http://www.fapesp.br/en and visit FAPESP news agency at http://www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.

Fundação de Amparo à Pesquisa do Estado de São Paulo

Related Fires Articles:

Setting fires to avoid fires
Despite having proven effective at reducing wildfire risks, prescribed burns have been stymied by perceived and real risks, regulations and resource shortages.
How does wildlife fare after fires?
Fire ecologists and wildlife specialists at La Trobe University have made key discoveries in how wildlife restores itself after bushfires, and what conservationists can do to assist the process.
Surprising findings on forest fires
Several years ago, an international team of scientists led by the University of Bonn raised sediments from the bottom of Lake Van in eastern Turkey reflecting the past 600,000 years.
Forest fires as an opportunity for ecosystem recovery
It is estimated that globally there are more than two million hectares of land in need of restoration.
Fighting fires before they spark
With warm, dry summers comes a deadly caveat for the western United States: wildfires.
How forest fires spoil wine
If wine is cultivated where forest fires occur more often, such as in Australia or Italy, aromas that make the alcoholic drink unpalatable can develop in the finished product.
Fires in Australia pop up in places already burned
Fires that span across the Northern Territory and Western Australia appear to have broken out in areas that have already been burned in previous fires.
Wildfires: More people, less fires
Every year, about 350 million hectares of land are devastated by fires worldwide, this corresponds to about the size of India.
Demographic changes increase the risk of natural fires
In many parts of the world, grass and forest fires pose a threat to animals and humans.
Oil fires in Libya continue
The oil refinery fires in Libya that were started by attacks on oil terminals in Libya in very early January continue.
More Fires News and Fires Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: The Power Of Spaces
How do spaces shape the human experience? In what ways do our rooms, homes, and buildings give us meaning and purpose? This hour, TED speakers explore the power of the spaces we make and inhabit. Guests include architect Michael Murphy, musician David Byrne, artist Es Devlin, and architect Siamak Hariri.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.