Native reforestation benefits biodiversity

Timber harvest and agriculture have had an enormous impact on biodiversity in many parts of the world over the last two hundred years of the industrial era. One such region is 20 to 50 kilometre belt of tropical dry evergreen forest that lies inland from the southeastern coast of India. Efforts to regenerate the biodiversity has been more successful when native tropical dry evergreen forest has been reinstated rather than where non-native Acacia planting has been carried out in regeneration efforts, according to research published in the Interdisciplinary Environmental Review.

Christopher Frignoca and John McCarthy of the Department of Atmospheric Science and Chemistry at Plymouth State University in New Hampshire, USA, Aviram Rozin of Sadhana Forest in Auroville, Tamil Nadu, India, and Leonard Reitsma of the Department of Biological Sciences at Plymouth explain how reforestation can be used to rebuild the ecosystem and increases population sizes and diversity of flora and fauna. The team has looked at efforts to rebuild the ecosystem of Sadhana Forest. An area of 28 hectares had its water table replenished through intensive soil moisture conservation. The team has observed rapid growth of planted native species and germination of two species of dormant Acacia seeds.

The team’s standard biological inventory of this area revealed 75 bird, 8 mammal, 12 reptile, 5 amphibian, 55 invertebrate species, and 22 invertebrate orders present in the area. When they looked closely at the data obtained from bird abundance at point count stations, invertebrate sweep net captures and leaf count detections, as well as Odonate and Lepidopteran visual observations along fixed-paced transects they saw far greater diversity in those areas where native plants thrived rather than the non-native Acacia.

“Sadhana Forest’s reforestation demonstrates the potential to restore ecosystems and replenish water tables, vital components to reversing ecosystem degradation, and corroborates reforestation efforts in other regions of the world,” the team writes. “Sadhana Forest serves as a model for effective reforestation and ecosystem restoration,” the researchers conclude.

Frignoca, C., McCarthy, J., Rozin, A. and Reitsma, L. (2021) ‘Greater biodiversity in regenerated native tropical dry evergreen forest compared to non-native Acacia regeneration in Southeastern India’, Interdisciplinary Environmental Review, Vol. 21, No. 1, pp.1–18.