Secondary Forests Research Network

2ndFOR is a collaborative research network focusing on understanding the ecology, dynamics, and biodiversity of tropical secondary forests and the ecosystem services they provide in human-modified tropical landscapes.

2ndFOR study published in Science today

10th December 2021

Tropical forests are converted at an alarming rate through deforestation, but also have the potential to regrow naturally on abandoned lands. A study published in Science shows that regrowing tropical forests recover surprisingly fast, and can attain after 20 years nearly 80% of the soil fertility, soil carbon storage and tree diversity of old-growth forests. The study concludes that natural regeneration is a low-cost, nature-based solution for climate change mitigation, biodiversity conservation, and ecosystem restoration.

We identified a set of three attributes – maximum tree size, overall variation in tree size and the number of tree species in a forest – that, viewed together, provide a reliable snapshot of how well a forest is recovering. These three indicators are relatively easy to measure, and managers can use them to monitor forest restoration. It is now possible to monitor tree size and forest structure over large areas and time scales using data collected by satellites and drones.

Read more about the study in The Conversation

This graphic shows how four groups of forest attributes – soil, ecosystem functioning, forest structure and tree biodiversity – recover as tropical forests regrow on former farm and pasture lands. For each category, the image shows the average percentage of recovery compared with old-growth forests after 20, 40, 80 and 120 years. Percentages in black squares show average recovery for the whole forest at each interval. Pixels&Ink, CC BY-ND

New 2ndFOR article published in PNAS

29th November 2021

This continental-wide study entitled Functional recovery of secondary tropical forests shows that regrowing tropical forests are quite diverse in their recovery; dry and wet forests differ initially strongly in their functional composition, follow different successional pathways, but become more similar in functional characteristics over time when forests grow older. The study, published today in the Proceedings of the National Academy of Sciences provides insights on which type of tree species should be selected for restoration plantings, thereby enhancing tropical forest restoration success.

Read more here

Picture by L. Poorter

Picture by R. Chazdon

Secondary forests

are forests that regrow naturally after nearly complete removal of forest cover for anthropogenic use (usually for shifting cultivation, conventional cropping or cattle ranching). Currently over half of the world’s tropical forests are not old-growth, but naturally regenerating forests of which a large part is secondary forest. In tropical Latin America, secondary forests cover as much as 28% of the land area.

Picture by F. Bongers

Tropical forests are home to more than 53,000 tree species, accounting for 96% of global tree diversity. These hyperdiverse forests are threatened by high levels of deforestation, mostly driven by agricultural expansion. Once agricultural fields are abandoned, they can be rapidly colonized by naturally regrowing forests, which are called “secondary forests”. Could these regrowing forests help reverse species loss and bring native species back?

Read our brief on the study published on march 2019 in the journal Science Advances

Watch the video made by IIES, Mexico, on our study Biomass resilience of Neotropical secondary forests published in the scientific journal NATURE in 2016