A study conducted by scientists from Brazil, the United States and Portugal investigated the accuracy and consistency of different satellite data collection with respect to the location and size of the burned area in the Cerrado biome, Brazilian savanna.
The results, published in the International Journal of Applied Earth Observation and Geoinformation, will help increase the output produced by Program Queimadas, a program run by the Brazilian National Space Research Institute (INPE) to monitor forest fires and fires by satellites and to calculate and estimate forest fires risk.
This study is linked to the Brazil Atmosphere-Atmosphere Fire System (BrFLAS), a project supported by the São Paulo Research Foundation – FAPESP. The main investigator is Renata Libonati, a professor at the Federal University of Rio de Janeiro (UFRJ) in Brazil, working with researchers at the University of Maryland (US) and the University of Lisbon (Portugal). This study is also one of several projects carried out as a follow-up to the main research of the first author Júlia Abrantes Rodrigues.
Some previous studies have shown that fire – which can be used intelligently as part of a well-considered strategy with zoning of total areas and rotating fire schedules – is very necessary to update the Cerrado (read more at agencia.fapesp.br/26064).
The use of fire that is careless, often criminal, to eliminate native plants and prepare land for plants and extensive livestock raising is a different story. "In this case, the area is burned repeatedly in very short intervals, almost always in the dry season, and no vegetation can survive. Natural adaptation is not possible," environmental engineer Alberto Setzer). Setzer is a researcher at INPE and co-author of the article.
"The most important aspect to consider is atmospheric emissions from combustion. Depending on the year, they can contribute between 28% and 75% of Brazil's total carbon emissions, contributing greatly to global estimates, because Brazil ranks seventh among world countries that is the biggest source of carbon emissions. Even 28% is very significant, while 75% is very serious, "Setzer said.
"The Amazon is a major concern in the past as far as fire is concerned, but the burning in Cerrado has become very alarming. This biome, especially the part known as MaToPiBa [an acronym that designates the area at the intersection between the states of Maranhão, Tocantins, Piauí and Bahia], has become a magnet for large-scale agricultural projects. For example, western Bahia has experienced brutal destruction, and almost all natural vegetation has been removed. "
Setzer noted that this change was very drastic and fast and that the scientific community was practically unaware of it. Therefore, the timeliness of this new study, which departed to answer the following question: "How many Cerrado were burned?"
Data from satellites operated by reliable organizations such as NASA and the European Space Agency (ESA) are global scale and relatively inappropriate for the study of regional phenomena, according to Setzer.
"In this particular case we are trying to improve the quality of the INPE output for use in measuring the burned area," Setzer said. "This study shows the limitations and errors of estimates of the global scale and those produced by INPE. The aim is to improve our data to arrive at more precise information about the burned area, including what data, when and where, and the results of emissions."
The Queimadas Program Portal offers up-to-date data on the subject. At a resolution of 1 km, it is possible to get data about the total burned area and the burn area based on biomes, year after year and month after month, as well as the percentage of each biomass from the total burned area. Maps also show their respective biomes. This portal offers LANDSAT quadrant images, maps and other detailed information for Cerrado at a resolution of 30 m.
"In our study, we calculated the errors and uncertainties of the data provided by satellite imagery. This is the first study of the type for Cerrado. We also found that data is more reliable for the northern part than the southern part of Cerrado. This is due to the nature of the southern biome smaller, so that the use of fire occurs in a relatively small area rather than on a very large plot of land. In the north, in areas such as Bananal Island, we measure almost continuous fires in an area of 10,000 km2 in a few years. occurs in the northern part of São Paulo or southern Minas Gerais [Southeast Brazil], where land use patterns are very different. This is an important finding because it shows you cannot have a single algorithm for all biomes, "Setzer explained.
At present, the impact on Cerrado is the largest in the area of fertile land. "Cerrado is practically destroyed, and the land is converted into plants or grasslands. In most cases, this is done in violation of environmental laws. In Amazon, the law requires that 80% of any property be abandoned. Untouched. In Cerrado "This requirement only applies to 30%, but even that small proportion is not enforced," he said.
About the 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 providing scholarships, scholarships and grants to investigators related to higher education and research institutions in the State of São Paulo, Brazil. FAPESP realizes that the best research can only be done in collaboration with the best international researchers. Therefore, he has built partnerships with funding institutions, higher education, private companies, and research organizations in other countries that are known for the quality of their research and have encouraged scientists funded by their grants to further develop their international collaboration. You can learn more about FAPESP at http: // www.fapesp.br /id and visit the FAPESP news agency at http: // www.agencia.fapesp.br /id to continue to be updated with FAPESP's latest scientific breakthroughs helping achieve through many programs, awards and research centers. You can also subscribe to the FAPESP news office at http: // agencia.fapesp.br /subscribe.
This story has been published on: 2019-05-29. To contact the author, please use the contact details in the article.