Restoring rainforest fragments: Survival of mixed-native species seedlings under contrasting site conditions in the Western Ghats, India
Historical fragmentation and a current annual deforestation rate of 1.2% in the Western Ghats biodiversity hotspot have resulted in a human-dominated landscape of plantations, agriculture, and developed areas, with embedded rainforest fragments that form biodiversity refuges and animal corridors. This study evaluates restoration efficacy for tropical rainforest under three different site conditions in the Anamalai hills, India.
Research goals & methods
The authors established restoration sites within three rainforest fragments (5, 19, and 100 ha) representing varying levels of degradation such as open meadow; highly degraded sites with dense Lantana camara invasion; abandoned exotic tree plantations (Eucalyptus grandis and Maesopsis eminii), and sites with mixed native and exotic tree canopy. Plots of 0.15-1.0 ha were opened in each of these sites and over 120 species were planted annually between 2000-2004 to establish mixed-species seedling stocks. Seedlings were monitored at 6-month intervals to establish survival rates at 6 months, 12 months, 18 months, and 24 months.
Conclusions & takeaways
Seedling survival was higher under canopy than in more open sites; half of the seedlings planted were of shade-preferent deep-forest species that would have struggled under greater direct sunlight. Seedling survival was also higher in larger plots as compared to smaller plots with more weed pressure. Retaining regenerating native species during weed clearing operations was crucial for rapid reestablishment of a first layer of canopy to shade out weeds and enhance survival of shade-tolerant rainforest seedlings.
Restoring Rainforest Fragments: Survival of Mixed-Native Species Seedlings under Contrasting Site Conditions in the Western Ghats, India. Restoration Ecology. 2009;17:137–147. doi:10.1111/j.1526-100x.2008.00367.x..
- Nature Conservation Foundation, India