The Impact of Deforestation on the Brazilian Amazon Rainforest
There’s a lot of talk about the impact deforestation has on climate change and the loss of both flora and fauna as a result. A major study of the Brazilian Amazon Rainforest was released this week that sheds new light on the many and varied environmental threats this ecosystem faces. The study revealed that the most detrimental land-use change is deforestation of primary forests in order to create pasture.
Let’s start by discussing the difference between a primary forest and a secondary forest. First, primary forests are forests that have native tree species where human activity is not clearly evident and the ecological balance is not significantly disturbed. On the other hand, secondary forests are forests that have grown back after natural or man-made practices, such as agriculture or ranching, have occurred. With this in mind, the research shows that transitions from primary and secondary forests to pasture through deforestation caused almost all biodiversity groups to decline by between 18 and 100 percent. Transitions from forest to mechanized agriculture had the most ecological impact but occurred less frequently than conversion of forests to pasture. Their results show that approximately 24,000 square kilometers a year or nearly 6 million acres a year are converted to pasture from primary and secondary forests in the Brazilian Amazon rainforest. To put that into perspective, Alaska’s Denali National Park and Preserve is approximately 5 million acres in total. Clearly, this type of detrimental deforestation occurs on a large scale annually.
So exactly how was this study conducted? The researchers collected data from 310 plots in the Brazilian Amazon rainforest and recorded how the changes affected biodiversity. They examined more than 2,000 species of trees, lianas, birds, and insects. They also observed the carbon and soil properties of these plots. Finally, the researchers used published data from 2006-2019 about how quickly the landscape has changed over the past decade.
"Deforestation of primary forests to create pasture is the most damaging land-use change in the Brazilian Amazon," said Dr. Alencar Nunes. "Our results show that transitions from primary forests to pasture were always classed as 'high impact, high rate' for biodiversity, carbon storage, and soil properties. This underlines the critical and urgent importance of combating deforestation, which has been increasing in the past few years."
Although it may seem that these discoveries are only negative, it is important to note that the researchers cite opportunities for positive action. There is hope for our future in protecting secondary forests and allowing them to mature. Their research proved that doing so can make a significant positive impact because the diversity of large trees doubled and small tree diversity increased by 55 percent when young secondary forests became older than 20 years.
Dr. Alencar Nunes said: "These are important findings as they show that there are a multitude of actions that can be taken to protect and improve the ecology of the Amazon. When farmers switch land from pasture to growing crops using mechanized agricultural methods, that is also impacting on biodiversity, but it is a process that is largely hidden when compared to deforestation.”
“By reducing the amount of land that is converted to mechanical farming, and by allowing secondary forests to regrow, we can deliver significant ecological restoration gains in the Amazon.”
"Our analysis helps to define and prioritize the local and regional actions required to stimulate a better Amazonia."
Thank you so much for reading! If you are interested in learning more about this study check out this link:
https://www.sciencedaily.com/releases/2022/06/220627165846.htm
