Successional dynamics of a regenerated forest in a plantation landscape in Southern India

In a new study researchers from ATREE and Gubbi Labs monitored native forest regeneration over 11 years in a eucalyptus plantation and compared it with the neighbouring primary forest. For the plantation forest, the study hypothesized that species richness, density, basal area and densities of old-growth species would increase over time. The hypothesis also claimed that compared to the primary forest, plantation forest would have higher species richness and density, but lower densities of old-growth species.

In 2016, the researchers repeated the protocol of a study that sampled the plantation forest in 2005, with thirty 10 by10 metre plots and enumerated trees saplings and seedlings.

The study found that in plantation forest, for trees, the species richness, density of gap, bird-dispersed and mammal-dispersed species increased by 67%, 156%, 116% and 238% respectively; whereas for saplings, density of gap, bird-dispersed and small-seeded species declined by 45.2%, 51% and 18.2% respectively over time. The study found that seedling densities did not change across functional groups. Stand basal area increased by 80.1% in the plantation forest. The primary forest had 446% greater density of closed-canopy trees compared with plantation forest.

Contrary to the hypothesis, the plantation forest did not accumulate significant densities of old-growth species over time, probably due to demographic filters that prevent them from attaining maturity.