The Secret of Terra Preta: How Amazonian Soil Could Revolutionize Plant Growth
Terra Preta da Amazônia, or Amazonian Black Earth (ADE), is a type of soil that could revolutionize plant growth. According to recent research, ADE can increase tree growth up to six times compared to traditional soils. This article explores the unique properties of ADE and how it could be used to improve plant growth and regeneration of degraded areas.
Terra Preta and its influence on plant growth
Features of Terra Preta
Terra Preta is a nutrient-rich soil that supports communities of microorganisms beneficial for plant growth. The native inhabitants of the Amazon have used ADE to grow food for centuries, without the need for fertilizers. According to Luís Felipe Guandalin Zagatto, a doctoral student at the Center for Nuclear Energy in Agriculture of the University of São Paulo, ADE is particularly effective in promoting the rapid growth of trees and improving their qualitative development.
Research has shown that the microbiota present in ADEs (bacteria, archaea, fungi and other microorganisms) is very beneficial for plant growth. The addition of ADE to the soil stimulated the growth of three tree species tested. Specifically, Brazilian cedar and yellow poinciana seeds grew two to five times their normal height in 20% ADE soil, and three to six times their normal height in 100% ADE, compared to growth in control soil. Additionally, the ADE contained more nutrients than the control soil: for example, 30 times more phosphorus and three to five times more each of the other nutrients measured, except manganese. It also had a higher pH.
Biotechnological implications and applications.
To carry out the experiment, Zagatto and his colleagues collected ADE samples in the Caldeirão experimental field, in the state of Amazonas. The control soil came from experimental plots maintained by the Luiz de Queiroz Faculty of Agriculture in Piracicaba, in the state of São Paulo. They filled 36 four-liter pots with 3 kilos of soil each and placed them in a greenhouse with an average temperature of 34°C, predicting the impact of global warming, since temperatures in the Amazon currently range between 22°C and 28 °C.
The research team does not propose the use of ADE as such, as it is a finite and well-protected resource. The objective of his research is to analyze the chemical properties of ADEs (nutrients, organic matter and pH), as well as enzymatic activity and other biological and biochemical aspects that benefit plants. “We need to understand exactly which microorganisms are responsible for these effects and how we can use them without the need for ADE as such. Therefore, we can try, for example, to replicate these characteristics through biotechnological developments. “This study was a first step in that direction,” Zagatto said.
Deforestation is a serious problem for Brazil, and not just in the Amazon. It is increasingly important to find ways to rapidly restore these areas, so that forests regrow and ecosystem services resume, with all the benefits they offer to the environment and human populations, including climate regulation and quality. of the air, as well as the storage of carbon in soil.
“In the study, our objective was to evaluate a possible improvement driver for tropical forest ecological restoration projects, more specifically in the Amazon, so that in the future these areas can return as much as possible to their original state,” he said. Zagarro said. “We believe these results are promising and demonstrate that using ADE traits in seedling production or even directly in the field can be a way to accelerate the ecological restoration of tropical forests.”