In Atlantic Forest restoration, connection between fragments is more important than fragment size

A recent study examining Atlantic Forest restoration has revealed that the connection between forest fragments, rather than their size, is crucial for seed richness and diversity. Seed dispersal through wind, water, or animals plays a key role in forest renewal and biodiversity preservation. Researchers from the Institute of Biosciences of São Paulo State University (IB-UNESP) analyzed the seed rain patterns across 52 Atlantic Forest fragments located throughout Brazil.

The findings, published in the Journal of Ecology, indicate that forest cover and precipitation are the main factors responsible for seed richness and diversity, regardless of fragment size. Small patches of forest surrounding green areas are more capable of regenerating themselves than large but isolated fragments in deforested landscapes.

The study analyzed seed traps, which collected 1.3 million seeds from 1,905 traps across these fragments, identifying 1,029 seed taxa. Areas with higher rainfall had more zoochorous seeds, which come from trees that produce fruits attractive to birds and mammals. Deforestation has led to a loss of large-seeded species that require wildlife for dispersal.

Forest fragments with low forest cover, particularly in drier areas, tend to be dominated by a limited set of pioneer species. These fragments often lack connectivity with other forest areas, limiting seed exchange and maintaining biodiversity. Prioritizing conservation strategies that target connected ecosystems and increasing surrounding forest cover can enhance seed exchange, improve species community functioning, and ultimately contribute to the restoration of functional ecosystems within the Brazilian Atlantic Forest.