Trajetórias espaço-temporais de palmeiras em resposta à fragmentação florestal na Amazônia Central

Abstract

Forest fragmentation is one of the biggest threats to global biodiversity. A new spatial configuration of the landscape can expose isolated areas to abiotic and biotic alterations that cause changes in the structure and composition of the remaining native vegetation. However, these changes may take some time to be noticed, especially in processes that depend on organisms with a long life cycle. Only long-term studies that consider different ontogenetic stages of plants can provide evidence of how and for how long the process of forest fragmentation can affect vegetation. However, despite being essential, such studies still need to be available. Here, we had the opportunity to compile data collected 15 and 42 years after the formation of forest fragments to analyze the spatial-temporal trajectory of palms, considering seedlings, juveniles, and adults. The permanent plots were in forest fragments of different sizes and adjacent continuous forests in the Central Amazon. As seen 15 years after isolation, we again recorded a sharp decline among the immature palm population in forest fragments. However, adult palms, previously unaffected by forest fragmentation, increased significantly in both environments over time. However, such changes did not alter the number of species or the composition of the palm assemblage when we analyzed the effect of forest fragmentation and different sizes of forest fragments. We conclude that there was low resilience among palm trees in population recovery after changes caused by forest fragmentation, and there was no clear evidence that even with a more significant number of reproductive palms, there was a success in establishing new individuals. This phenomenon can be further synergistically aggravated by the recurring changes in new climate patterns witnessed in the region.