Wetlands in the Pantanal went from 7.2 million hectares in 1988 to 5.1 million hectares in 2018, the year of the last flood em 1988 para 5,1 milhões de hectares em 2018, ano da última cheia 

Pantanal biome highlights from Collection 7

Data obtained by MapBiomas from the analysis of satellite images between 1985 and 2021 confirms that the Brazilian Pantanal has been showing much drier patterns in recent years. The year 2021 represents the driest ever observed, with a wetland area equivalent to 1.6 million hectares - 76% less than at the start of the series (6.7 million hectares in 1985).  

As this is a biome where the water surface varies seasonally, the researchers evaluated the variation between the years with flood peaks and drought peaks. Adding together flooded fields and surfaces covered by water, the reduction was 29% in the extreme years of flood peaks (from 7.2 million hectares in 1988 to 5.1 million hectares in 2018) and 66% in the extreme years of drought peaks (from 4.7 million hectares in 1986 to 1.6 million hectares in 2021).  

In the most recent years of the series, it can be seen that the floods are getting smaller and smaller, both in terms of area and duration. In 2020 and 2021 the flooded area was below the already decreasing trend, with the most flooded months less expressive than the driest months of the other years in the series. 

Regardless of seasonality, the data shows that every month of the year shows a downward trend in the area flooded. Considering the monthly mapping and the area, trend and frequency data, in the period from 1985 to 2021 the Pantanal is flooding smaller areas and also for less time.

In the last 37 years, the surface area of water in the Pantanal has gone from 2.7 million hectares in 1985 to 500,000 hectares in 2021. In 1985, 4 million hectares were wetlands; in 2021, it was 1.1 million hectares. In the same period, grasslands went from 1.6 million hectares in 1985 to 5.7 million hectares in 2021. Agricultural activities, meanwhile, occupied 600,000 hectares in 1985 and 2.8 million hectares in 2021. In 1985, 6 million hectares were forest and savannah; in 2021, 4.9 million hectares.

"The Pantanal is suffering from multiple and simultaneous vectors of local, regional, national and global degradation," explains Eduardo Reis Rosa, from MapBiomas. "At a local level, we see a process of converting natural areas into exotic pastures. The occupation of the plateau area, without respect for the springs and permanent protection areas along the rivers, is affecting the quantity and quality of water and causing siltation in the rivers of the plain. There is also a high frequency of fires, which hinders the natural recovery of the biome. On a regional level, we also have the advance of dams, PCHs, artificial drains and roads, which are compromising the flow of water. At a national level, we are seeing greater irregularity in the rainfall regime due to the deforestation of the Amazon and the impairment of its ability to pump moisture into the atmosphere. Finally, the Pantanal is also suffering from the worsening climate crisis," he said. 

The conversion of natural grasslands to pastures planted with exotic species is emblematic of the Pantanal's degradation process. A biome that has historically been occupied by livestock activities, the Pantanal has seen the advance of exotic pastures over natural ones as the receding waters leave larger tracts of land exposed. However, this process has left a legacy of soil degradation, most pronounced in the eastern part of the biome:

The Upper Paraguay river basin is made up of the lowland area (the Pantanal) and its headwaters in the plateau area (comprising areas of the Cerrado and the Amazon). The picture of the basin in 2021 shows a big difference in preservation between the plain (where 83% of the area is still natural) and the plateau (only 43%). It is worth noting that all of the Pantanal's river springs (+140,000) are located on the plateau. Among the Permanent Preservation Areas of rivers (30m) and springs (50m) in the basin, 43% of the area is under anthropic use in 2021 (656,000 ha), of which 185,000 hectares of preservation areas have been converted to anthropic use in the last 37 years. 

MapBiomas also calculated figures for the Upper Paraguay Basin:

• In 1985, 8.9 million hectares were forested; in 2021, there were 5.9 million - a loss of 3 million hectares in 37 years.
• In 1985, 8.9 million hectares were forested; in 2021, there were 5.9 million - a loss of 3 million hectares in 37 years.
• In 1985, 8.5 million hectares were occupied by agricultural activities; in 2021, there were 14.7 million - a gain of 6.2 million hectares in 37 years. 

In all, the biome had a total of 12 million hectares of natural areas in 2021, a loss of 12% in 37 years. Last year, 39.6% was occupied by grassland formations, 19.7% by forest formations, 16.8% by pastures, 12.9% by savannah formations, 7.1% by flooded fields and 3.5% by water.