Deforestation in SP and surrounding areas was 370 hectares in one year – 09/28/2023 – Environment

The vegetation area of ​​the São Paulo macrometropolis had 273 deforestation alerts from July 2022 to July 2023, which meant the loss of 370.73 hectares, the equivalent of two Ibirapuera parks demolished. A significant portion of this devastation occurred in spring systems that surround, integrate and supply the capital of São Paulo with water.

The data, anticipated to Sheetare part of the project to monitor and generate deforestation alerts in water sources in the city of São Paulo and its surroundings, under the responsibility of the IDS (Democracy and Sustainability Institute) together with Semil (State Secretariat for the Environment, Infrastructure and Logistics).

The information will be released this Thursday afternoon (28), at Alesp (Legislative Assembly of São Paulo).

The initiative is the result of a parliamentary amendment by state deputy Marina Helou (Rede) who allocated almost R$250,000 for the partnership and implementation of the project.

The macrometropolis concerns more than a hundred municipalities in the state, including the city of São Paulo. The area considered has tens of millions of inhabitants and great economic relevance.

Just over 68 of the deforested hectares are in the PCJ watershed system, an acronym that designates the basins of the Piracicaba, Capivari and Jundiaí rivers. Next, the systems of Alto Cotia (21.53 hectares), Itupararanga (14.87), Cantareira (13.28), Guarapiranga-Billings (10.82), Paraíba do Sul (8.54) and Alto Tietê appear. (5.07).

The basins considered above are of interest for public water supply in the region. The rest of the felling is made up of points outside these hydrographic units.

The hundreds of hectares felled do not necessarily mean areas with illegal deforestation. An area with vegetation may be removed after authorization.

Considering only the areas within the aforementioned systems, 118 deforestation alerts were registered. Of these, around 41% (49 alerts) were considered non-reportable, that is, they were disregarded by the state secretariat after an audit. These cases could be, for example, deforestation that was licensed or a landslide.

Sergio Augusto Ribeiro, water security consultant at IDS, says that part of the objective of the initiative is to facilitate access to this type of information for the population. Starting this Thursday, it will be possible to view each of the deforestation warning points online on an IDS page.

Another objective is to speed up and make field inspection by São Paulo environmental authorities more precise.

The quest for zero deforestation and the PCJ case

Although not all deforestation is illegal, the country is seeking zero deforestation, whether legal or illegal. Furthermore, in areas such as those observed by the project, clearings impact the population’s water security.

“From the point of view of water security, there are places that are more important than others. We have to have intersectoral policies and actions focused on these regions”, says Ribeiro.

It is worth remembering the water crisis experienced by São Paulo in the last decade and, in more recent years, the fear that has surrounded the levels of the reservoirs that feed the capital, such as Cantareira.

Currently, El Niño is underway, which could lead to changes in the rainfall and temperature cycle across the country. “We are entering a more dramatic scenario for this issue of water security and we are still observing a situation where there is a considerable suppression of vegetation”, says the IDS specialist.

Ribeiro cites the PCJ basin as an outlier, with 58 alerts registered, that is, almost half of the records in the spring systems observed in the period. “It turns on a yellow light noticeably for this system.”

Marcos Rosa, technical coordinator of the MapBiomas platform and member of the project, highlights that the PCJ basin occupies a larger area, which, proportionally, could partly explain a greater number of alerts. Considering the type of clearing, compared to other basins, the PCJ presents a considerably higher number of alerts linked to agricultural expansion.

In other basins, says Rosa, it is more common to see deforestation linked to urban expansion. “They are normally very small alerts. It’s what we call the little ant effect.”

Rosa remembers that, although São Paulo has recently seen more vegetation gain/recovery than loss, attention is still needed. “These small areas accumulate and, normally, people don’t see them,” she says.

“It’s still a constant concern, because, despite not being a very significant value, these forests here, especially in this region of springs, are very important. We must always be talking about recovering areas that were lost and ending deforestation.”

How monitoring is done

The technical coordinator of MapBiomas points out that one of the developments in relation to what was done before was to apply greater refinement to monitoring, to examine possible smaller deforested areas.

The initial identification of alerts is done by artificial intelligence. Then there is a visual validation by IDS, using satellite images from the company Planet. It is generally possible to observe vegetation removals of up to 0.15 hectare. To find out if there really was deforestation, the most recent images of the location are superimposed with the Forest Inventory of the State of São Paulo.

The alert is also validated by Semil, which checks whether there was authorization for the withdrawal.

Because they are looking specifically at supply systems, another precaution is necessary. When we talk about deforestation monitoring, we usually refer to forest areas, but detection in the specific systems observed in São Paulo and surrounding areas can be more complex, considering the humid areas around bodies of water.

Natural flooding and drought processes can end up generating false alerts (which fall into the non-reportable category), hence the importance of checking.

Rosa compares it with the Amazon situation, which is much larger, where there has recently been an increase in deforestation of more than one hundred hectares. “It’s a hundred football fields. It’s basically a guy who thinks he’ll never get charged,” she says. “The smaller the deforestation, the more difficult both detection and action.”