Biodiversity–productivity relationships in small-scale mixed-species plantations using native species in Leyte province, Philippines

Background

The authors of this study identified environmental and biodiversity factors to explain variation in productivity at Rainforestation sites across the Philippine islands.

Conclusions & Takeaways

In mixed species plantations, no correlation between productivity, measured as the basal area increment, and several species richness indices was found. They argue, however, that a higher species diversity may bring other benefits such as non-timber forest products to the local community. Nguyen et al. found a higher productivity in monocultures and a positive correlation between stand productivity and the share of exotic species, and the share of fast-growing species in a stand. The authors examined additional factors to biodiversity and concluded that biodiversity, stand density and stand age had a combined effect on the productivity. These factors and the growth rates greatly differed between sites. Other factors such as topographical position, slope degree or ground cover showed no significant relationship to the stand productivity. Finally, in Rainforestation Farming sites a greater stand growth was found in young stands, likely due to the higher densities in these stands. After 10 years, stand production decreased but this effect may be compensated using forest management methods such as thinning.