Deforestation has exacerbated the natural disaster in Southeast Asia
Decades of extensive deforestation of rainforests weakened Indonesia's resilience to the extreme weather that hit the country in late November. The result is a dramatic increase in flooding and landslides.
FLOOD: A building buried in mud after the flood disaster in Aceh province on Sumatra, Indonesia. Photo: Khairu Syukrillah/ZUMA Press Wire/Shutterstock
By Rainforest Foundation Norway.
The tropical cyclones that struck Indonesia, Thailand and Sri Lanka have caused widespread destruction and loss of life. More than 1,500 people are reported dead, and hundreds of thousands are displaced.
Sumatra, where deforestation is most severe, has suffered the greatest impacts.
Several experts and representatives of the Indonesian government now point out that extensive deforestation has contributed to worsening the flood disaster and triggering extensive landslides.
“We extend our deepest condolences to the victims and their families. These tragedies are a stark reminder that deforestation in Sumatra doesn’t just destroy ecosystems — it puts people directly in harm’s way. Without forest cover to stabilise soil and regulate water, extreme rainfall now triggers far more severe floods and landslides,” says Sinta Lestari, head of the Indonesia and Papua New Guinea team at Rainforest Foundation Norway
PALM OIL: Large areas of rainforest in Indonesia have been destroyed to make way for palm oil plantations. Photo: Forest Heroes
Trees protect against flooding and landslides.
Tree root systems play an important role in stabilising the terrain, especially where it is steep. When forest cover is removed, the risk of erosion and landslides increases during heavy rainfall.
Extensive deforestation – often to make way for agriculture, mining and development – has also led to the soil losing its ability to absorb and retain water. The result is increased surface runoff and a significant rise in landslides and floods.
Rainforest loss exacerbates climate change, increasing the frequency of extreme weather events such as floods and landslides.
REPLANTING: A man from the local community of Long Jalan in the Indonesian province of Kalimantan on the island of Borneo plants a tree. One of the Rainforest Foundation's partners in the country supports the local community in managing their forest areas. Photo: Jon Dalsnes Storsæter/Rainforest Foundation
Replanting, cooperation and stopping illegal logging
Environmental researchers warn that the situation will worsen if deforestation continues at the same pace. They emphasise that forests not only serve as protection against flooding and landslides, but also play a key role in regulating the local climate and preserving biodiversity.
"To prevent future tragedies, Sumatra needs large-scale reforestation, better land-use planning, and consistent enforcement of existing laws and regulations", says Sinta Lestari.
“The disasters remind us how important it is to strengthen the health of our forests moving forward. While many pressures on Sumatra’s ecosystems have accumulated over time, this moment presents an opportunity for the government, civil society, and communities to collaborate on long-term recovery. By prioritising ecological restoration and sustainable land management, we can build a more secure future for the region”, says Mufti Barri, executive director of Forest Watch Indonesia
Barri also emphasises the role of unity and cooperation with local communities:
“Forest loss is a reality felt across Sumatra, and addressing it requires clarity and shared commitment. Rather than becoming stalled in technical debates, we should unite around practical, evidence-based strategies that reduce forest degradation and support community well-being. Strong collaboration will ensure that policies translate into real improvements on the ground”.