Find out how deforestation in the cerrado generates a water crisis – 06/04/2023 – Environment

With 27 million hectares lost in the last four decades —the size equivalent to the state of Tocantins—, the cerrado is dying. In 2023, the biome has been suffering an average of 150 daily deforestation alerts, according to data from the SAD Cerrado platform, developed by Ipam (Amazon Environmental Research Institute).

The conversion of native forest into soy, corn, sugarcane and cotton crops would bring less concern to scientists if its vegetation were not directly linked to the national water dynamics.

Agribusiness is undergoing an expansion process in the region known as Matopiba (name formed by the abbreviations of the states of Maranhão, Tocantins, Piauí and Bahia).

Biologist Mercedes Bustamante, who is president of Capes (Coordination for the Improvement of Higher Education Personnel) and one of the leading experts on the subject, says that the red light is on.

“The São Francisco hydrographic region, already quite socially vulnerable, and the Pantanal, with its enormous ecological relevance, are being affected by the reduction in the amount of water that enters the cerrado. In addition, the quality of the water is also being harmed by contamination of plantations.”

A world biodiversity hotspot, the biome has 11 types of forest formations ranging from riparian forests to swamps. The same diversity extends to the relief. Thousands of springs sprout from its mountains, plateaus, plateaus, plateaus and levels, supplying eight hydrographic regions of the country.

In the dry season, the trees draw water from the water table, but in the rainy season, it is their deep roots that drain it into the aquifers, recharging them.

Endemic species, such as the pequi tree and the mangab tree, have branched roots that reach more than ten meters in length. It is because of this important function that the biome earned the nickname “inverted forest”.

In addition to deforestation, the overexploitation of water by agriculture, which uses central pivots and suction pumps, is also lowering the water table, according to specialists.

“In the north of Minas, the volume that is being removed from the geological reserves is greater than that which enters, so the level of the water table drops. There is a lack of public policies for the rational use of this limited resource”, says engineer Walter Viana.

For 15 years, he has been monitoring the disappearance of footpaths in the Grande Sertão National Park region with flow meters, tube wells and a meteorological station.

“The problem is that this water tank [o aquífero] has background. It won’t take long for the worst to happen”, says Viana, revealing that in another basin in Minas Gerais, the Rio Verde Grande, the groundwater abstraction rate is 218% higher than the recharge rate. The largest public project in irrigated agriculture from Latin America, Jaíba, was installed in the region during the military period and still operates.

The National Campaign in Defense of the Cerrado, created in 2016, brings together more than 50 national and international organizations. Water conservation is one of its main goals, as well as the claim for recognition of traditional communities spread throughout the region.

Maiana Maia, executive secretary of the network, also warns against the disorderly use of aquifers.

“We are suffering irreversible devastation processes. The country wells are drying up and the reports from the water bodies themselves point out that the underground reserves are at risk. More than 90% of the pivots in the country are in the cerrado, subtracting water for irrigation on a large scale”, scores.

Maia comments that the population associates supply crises with the lack of rain, but civil society needs to be aware of the consequences of this excessive use.

She believes that overexploitation of underground reservoirs could cause damage in other regions of the country, as river flows tend to decrease due to the connection between groundwater and surface water (springs, streams and rivers).

In western Bahia, a region that has been breaking consecutive records of deforestation according to the Prodes Cerrado, environmentalist Marcos Beltrão documents the threats to the Urucuia, one of the most important aquifers in the biome.

“The devastation of forests for planting soy is happening in the flat areas of the plateaus, which are precisely the recharge areas. There are streams that have already dried up and I see the sources migrating from place because the water table has dropped.”

A resident of Correntina (BA), Beltrão warns of the loss of biodiversity in the municipality, one of the five leading agricultural GDPs in Bahia. At the age of 41, he noticed that animals such as alligators and anacondas no longer exist where he used to swim as a child.

In Balsas, the epicenter of agribusiness in Maranhão, retired Antonio de Moraes acts as a pastoral agent supporting rural communities. He confirms that water problems are also intensifying there.

“In Uruçuí, where the Parnaíba River meets the Balsas, on the border with Piauí, they even built a soccer field on the dry riverbed. How are we going to avoid water collapse with so much felling happening in APPs [áreas de preservação permanente]?” he asks.

For biologist Mercedes Bustamante, reducing deforestation is an urgent task. High rates of devastation began in the early 1980s, when public programs such as Prodecer (Japanese-Brazilian Cooperation Program for the Agricultural Development of the Cerrados), a pilot project for agricultural development launched in partnership with the government of Japan, started to be implemented.

Until then, the biome’s acid lands were considered unsuitable for agriculture.

“The scale of the impact is already felt in the entire cerrado. And what worries me most is time. The longer we take to bring down these rates, the less effective the restoration policies that come will be”, says the president of Capes.

The biologist calculates that it would take about 30 years for the cerrado to recover. Without stopping the environmental damage, however, the most biodiverse savannah in the world, which took 40 million years to reach such biological richness, could succumb in this century.