Deforestation for monoculture and pasture is the main cause of a 34% decrease in river flow by 2050.
In the Cerrado region, 93% of river basins may experience a reduction in water availability, according to the study. The heavy impact of deforestation and climate change on the streamflows of the Brazilian Cerrado biome and a worrying future, supported by ISPN. According to the research, the biome could lose 34% of its water flow in the next 28 years. The study is currently under review by the scientific journal. Sustainability The study concluded that deforestation is the main cause of this decrease, responsible for 56% of the impact. A loss of 23.653 m³/s could occur by 2050 in the rivers analyzed alone; this loss is equivalent to the flow of eight Nile Rivers.
The situation is a cause for concern locally, nationally, and globally. The biome's water resources are becoming increasingly scarce locally, with river flow already declining by 15,4%. Even so, water continues to be exported to China, the European Union, and the United States in the form of "virtual water," that is, water consumed in the production of grains and meat.commodities).
The research analyzed the behavior of 81 river basins in the Cerrado biome between 1985 and 2022. Of these, 88% already show a decrease in flow due to intense changes in land use within the basin's area. This high number indicates a systemic trend of water scarcity and increased water stress until 2050, especially caused by large-scale agricultural occupation, agribusiness.
The study draws attention to changes in land use due to the expansion of agriculture and pastureland, responsible for approximately 46% of the country's greenhouse gas (GHG) emissions, which is one of the factors impacting climate change caused by agribusiness. This impact then reverberates, intensifying droughts, impacting agriculture itself, and amplifying conflicts over water.
Change in water governance
The main conclusion of the analysis is that the expansion of agriculture to commodities Water scarcity and other issues are intrinsically linked. Yuri Salmona, a geographer with a doctorate in Forestry Sciences from the University of Brasília and responsible for the research, comments that the increase in exports of... commodities The way water is consumed has changed water governance.
“Local, regional, and national controls over the Cerrado's waters have been replaced by actors who dominate the global agricultural product chain,” says the expert. This means that the river water, instead of benefiting local communities or the Brazilian population, is being controlled by agribusiness companies that divert the water flow for irrigation and send water to importers in the form of… commoditiesSalmona indicates that the use of water for agricultural production in Brazil must be rigorously monitored and evaluated by government agencies that guarantee the collective interest over private interests.
Climate changes
Although climate change also interferes with the reduction of river flow, the research shows that deforestation is the single largest factor affecting water security. Through statistical tests, validated models, and repeated checks to map the oscillation of river flow over time, Salmona and his colleagues were able to establish projections for the coming decades and analyze them by isolating the effects of deforestation and climate change. The result showed that climate change contributed 43% to the reduction in flow, less than deforestation, which is responsible for 56% of the negative impact on water. And future models produced by the study indicate that the role of land use in reducing the flow of Cerrado rivers should have an even greater weight.
This conclusion was reached by observing the increase in potential evapotranspiration, associated with the increase in temperature and radiation. Although climate change was felt more intensely during the dry season, it was possible to verify that changes in rainfall patterns are not the main factors in reducing flow rates.
Yuri Salmona comments that the misuse of land for agricultural exploitation intensifies the negative consequences of climate change. “We are compounding the negative effects of climate change through increased deforestation and the overuse of water for large-scale crop irrigation; we are working against ourselves. We are losing the chance to mitigate the effects of climate imbalance and are increasing concerns about water availability,” he laments.
According to National Water AgencyBased on the 2018 water resources situation in Brazil, 68% of water consumption is by agriculture. Combined with livestock farming, 80% of the water is committed to agribusiness, which in itself, according to... MapbiomesIt is responsible for 97% of deforestation in the Cerrado, the country's main carbon emitter.
Socio-environmental conflicts and water monopoly
Of the basins analyzed, three rivers present emblematic cases where the change in flow pattern occurred from 1997 onwards. These are the Arrojado River (BA), the Ondas River (BA), and the Corda River (MA). The latter, whose situation is the worst of all, may become intermittent in the coming years if the rate of deforestation continues at the current pace. All three rivers supply traditional communities in the region, but also the agribusiness that occupies immense areas in these territories of MATOPIBA, an acronym that defines the Cerrado portion of the states of Maranhão, Tocantins, Piauí, and Bahia. There, the number of conflicts over water continues to grow.
In western Bahia, for example, since 2012 the agribusiness industry has had unrestricted access to water, in a region experiencing increasing scarcity and worsening social conflicts due to water insecurity. There, the sector has been encroaching on rivers that supply water and territories that are home to communities of traditional grazing lands, traditional farmers, family farmers, and fishermen, with the aim of expanding plantations, generating revolts and protests from the population.
According to one investigation by Agência PúblicaIn western Bahia, agribusiness extracts 1,8 billion liters of water per day free of charge. This volume of water is enough to supply approximately 11,8 million Brazilians, a population larger than that of 22 Brazilian states and the Federal District. Part of this water is collected through dams in streams and wetlands, direct intake from rivers, and through wells that access groundwater that makes up the Urucuia aquifer.
Water and energy importance of the Cerrado.
Known as the "cradle of waters," the biome is home to the headwaters of 8 of the 12 most important river basins in the country and the second largest underground water reservoir in the world, the Guarani and Urucuia aquifers. Furthermore, it supplies 70% of the water for the São Francisco River, which supplies the Brazilian Northeast region, and 47% of the water for the Paraná River, which supplies the Itaipu hydroelectric dam. Its waters are also important for Bolivia, Paraguay, Argentina, and Uruguay.
Besides quenching thirst, the lack of water directly interferes with the availability of electricity in Brazil, whose energy matrix is based on hydroelectric power. For Yuri Salmona, the future is worrying. “Our analysis indicates that we are embracing a future of uncertainty regarding water availability in the Cerrado biome. The data allows us to predict a critical decrease in water availability and, consequently, an increase in conflicts over water,” he states. According to the researcher, the most affected will be local traditional communities, but also agribusiness itself and a large part of the Brazilian population, which depends on the waters of the Cerrado.
Need for conservation
As a supporter of the research, ISPN highlights the need for the implementation of specific public policies for the Cerrado biome, guaranteeing environmental conservation and the protection of the people who are its guardians. The Institute's public policy advisor, Guilherme Eidt, emphasizes that the Cerrado is at risk and needs attention just as much as the Amazon.
"Keeping the Cerrado standing is fundamental to guaranteeing food security, water security, energy security, global climate security, and maintaining socio-biodiversity. The peoples, traditional communities, and family farmers are essential for environmental conservation and climate balance," he points out.
According to Eidt, it is necessary to value non-forest biomes and encourage a policy of transparency in the supply chain. commoditiesthat allows products to be traced back to their origin. The lawyer also adds that importing countries and international legislation are just as important and responsible as Brazil in this task.
“It is important that European regulations guarantee the inclusion of other natural ecosystems within their scope. The European Parliament approved an ambitious text that must be ensured through dialogue with other European institutions. We believe in a different development model, one that generates income while conserving the environment,” concludes Eidt.
Photo: ISPN Archive/Thomas Bauer