A study contributed by researchers from CMU Faculty of Science titled ‘The road to recovery: a synthesis of outcomes from ecosystem restoration in tropical and sub-tropical Asian forests’ revealed that forestation in areas with an existing forest canopy had higher success than in fully-deforested areas, having significant implications on the worldwide attempts in tropical forest restoration.
The CMU research team was led by Associate Professor Dr. Stephen Elliott of The Forest Restoration Research Unit (FORRU-CMU) and Ms. Benjaphan Manohan, a graduate student in biology. The research studied the outcome of forestation on the restoration of tropical and sub-tropical forests in Asia, using a synthesis of the mortality and growth data of trees planted in 176 sites, including FORRU-CMU’s demonstration plot. The structural and biodiversity recovery of the actively restored and naturally regenerating forest plots were compared.
The results have shown that forestation attempts in fully-deforested areas were less successful than in the areas with existing canopy. The trees planted in the latter had a higher survival rate of around 20 per cent, highlighting the importance of preventative and protective measures to take great care of planted trees in highly-disturbed areas. However, this remains a challenging goal due to the lack of effective ecosystem restoration techniques.
One of the approaches recommended in the study is the framework species method adopted by FORRU-CMU, in which 500 trees of 20 – 30 local woody species found in nearby natural forests are planted per a 1,600 m2 of land. The selected tree species should have dense spreading crowns and be tolerant of exposure to sunlight and aridity, canopy-shaped, allelopathic, attractive to seed-dispersing animals such as having a fruit or a flower that attracts seed-dispersers, and easy to propagate.
To succeed, forest restoration also requires collaborative efforts by the community for it to become a source of food and income for locals. To drive sustainable restoration, the researchers have educated the community on seedling production, plot preparation, and planting and nurturing, as well as wildfire prevention and collection of seedling survival data. For more information, visit https://www.forru.org/th
Although the process is full of challenges and takes a long time to succeed, the implementation will face fewer issues if the contexts, species, size and quantity are taken into account, along with close supervision and data collection of the survival and growth of the seedlings in the actively restored plot for further analysis on factors affecting the restoration. CMU is among millions worldwide who are working to restore the forests and biodiversity, combatting climate change by reducing carbon in the atmosphere.