Climate Change Spurs Growth in Amazon Rainforest Trees

Syllabus: GS1/ Geography,  GS3/ Environment

Context

• A recent study published in Nature Plants  reveals that trees in the Amazon rainforest are steadily increasing in size due to rising levels of atmospheric carbon dioxide (CO₂).

Key Findings of the study

• Tree Growth: Amazon trees are getting bigger, with average diameter increasing by ~3.3% per decade.
  • Rise in CO₂ levels (nearly 20% in 30 years) led to the carbon fertilisation effect, where higher CO₂ enhances photosynthesis and accelerates growth.
• Shift in forest structure: The accelerated growth of larger, canopy-level trees is happening at the expense of smaller trees, whose numbers are declining. This fundamentally changes the forest’s structure and biodiversity.
• Shift in forest structure: The accelerated growth of larger, canopy-level trees is happening at the expense of smaller trees, whose numbers are declining. This fundamentally changes the forest’s structure and biodiversity.

Amazon Rain Forests

• Location: The region belongs to nine nations of the South American continent.
  • It is bounded by the Guiana Highlands to the north, the Andes Mountains to the west, the Brazilian central plateau to the south, and the Atlantic Ocean to the east.
• Area Covered: The majority of the forest, 60%, is in Brazil, followed by Peru with 13%, Colombia with 10%, and with minor amounts in Bolivia, Ecuador, French Guiana, Guyana, Suriname and Venezuela.
• Climate: Hot and humid climate with temperatures of 26-30°C throughout the year.
  • There are no periodic seasons.The precipitation ranges from 2,000 mm to 10,920 mm annually. 
• Tribes: Yanomamo, Kayapo, Akuntsu, Matses, Tupi etc.
• Fauna: Anaconda, Jesus lizard, howler monkey, golden lion tamarin, jaguar, sloth,     spider monkey, Amazon River dolphin, toucan and the scarlet macaw, poison dart frog and the glass frog.
• Flora: Moist broadleaf tropical rainforest like myrtle, laurel, palm, acacia, rosewood, Brazil nut, rubber tree, mahogany and Amazonian cedar. 

Significance of the Rainforests

• Lungs of the planet: Rainforests generate about 20% of the world’s oxygen and its trees play a key role in reducing pollutant levels.
• Fight climate change: They act as a crucial buffer in the global fight against climate change as it holds tremendous capacity to store carbon.
  • It is estimated that around 150-200 billion tonnes of carbon are stored in the Amazon rainforest.
• Biodiversity: Rainforests house a vast array of plant and animal species, many of which are found nowhere else and some of which are endangered.
• Medicinal Properties: Many of these plants contain bioactive compounds capable of treating diseases that are not yet curable, especially cancer.

Threat to the forests

• Climate Change: Due to climate change the forests are witnessing various challenges like changes in rainfall patterns,pollution etc.
• Deforestation: The size of the Amazon forest shrank dramatically as a result of settlers’ clearance of the land to obtain lumber and to create grazing pastures and farmland. 
• Wildfires: It causes threat to the survival of ecosystems and biodiversity. The 2019 forest fires in the region have led to widespread devastation in the region.

Concluding remarks

• Rainforests are nature’s living archives, holding irreplaceable biodiversity and regulating the planet’s climate. 
• Their protection is not just an environmental imperative but a safeguard for humanity’s future, linking ecological health with social, cultural, and economic resilience.

Source: IE