Embrapa researchers provide guidance on how to recover agricultural soil after fires

The municipalities of Mato Grosso do Sul recorded rainfall last weekend, some more than others. It may have eased temperatures, but the damage caused to the soil by the fires is not resolved by the rain. According to researcher Michely Tomazi, from Embrapa Agropecuária Oeste (Dourados, MS), the fires eliminate soil cover due to the burning of the straw left by previous crops, which was the main means of protection against the direct action of the rain, increasing the risk of erosion and loss of nutrients, which are readily available in the ashes, in addition to others released during the burning. In addition, it affects the soil microbiota, which lives mainly on the surface.

For a short-term solution, researcher Rodrigo Arroyo Garcia says that the ideal for soybean producers in Mato Grosso do Sul would be to immediately plant millet or crotalaria juncea and cultivate them for about 50 days to form some type of soil cover and then plant the soybeans in November 2024.

Michely emphasizes the need to establish, mainly, organic matter and recover soil nutrients. The main soil restorer will be the cultivation of plants, not only plants of commercial interest, but also cover crops and grasses, “which would be ideal for faster recovery”.

In the long term, the recommendation is to implement a crop rotation system that introduces other plants that are also beneficial to the soil and to the diversity of the biota lost due to the fires. The researcher warns that if rural producers continue to carry out crop succession, with low biomass input, the soil may take more than ten years to recover from the fires or “never recover”.

According to her, the time it takes for the soil to recover depends on the care and “dedication in introducing cover crops, in plants that are soil restorers, often giving up some agricultural crop”, says Michely. For those who work with crop-livestock integration (ILP), the best option, according to her, is to create pasture at this time and let the cattle graze, remaining in this condition for at least a year, “this way the result for the soil and for the economic culture will be very good”, she states.