Trees, Forests and People (Dec 2023)
Life histories and extraction impacts models in two untapped Geonoma palms
Abstract
The sustainable management of wild useful palms is crucial for their long-term survival. To understand how populations respond to extraction, it is necessary to examine the impacts of extraction in relation to their life histories in their habitat. A suitable genus for studying extraction responses and understanding life histories is Geonoma, as it exhibits a variety of demographic strategies, has a high potential for use, and some species are considered as untapped sources. Two species, Geonoma orbignyana and G. undata, are used as ornamentals for domestic purposes and commercialized in small-scale markets. They differ in their habitats, with G. orbignyana found in the understory and G. undata in more open spaces, suggesting different life histories. Therefore, the main objective of this study was to simulate the impacts of extraction for ornamental purposes in G. orbignyana and G. undata and identify the relationship with their life histories. The research was conducted in the Andean Forest of Chicaque Natural Park, Colombia in 2019–2021. We determined the demography of the two species, using Integral Projection Models (IPMs), and simulated the extraction of juveniles, leaves, and fruits. We found that both species exhibited typical understory palm patterns in terms of survival and growth rates. However, G. orbignyana had lower maximum individual size and onset of fecundity, indicating understory strategies, while G. undata displayed mixed strategies. The population of G. undata declined during both census periods due to high elasticities on juveniles, and extracting of juveniles is unsustainable, contrary of extraction of fruits and leaves, that seems to be sustainable under certain scenarios. Similarly, the extraction of leaves and fruits in G. orbignyana is potentially sustainable if occurring on specific sizes and rates, but the extraction of juveniles depletes the population. These findings suggest that sustainable extraction practices can be implemented to untapped palm populations while ensuring their conservation. To achieve this, it is crucial to protect the sizes and processes related to the growth and survival of acaulescent juveniles. Only after ensuring their growth should any extraction activities be considered. By adopting these practices, we can promote the responsible use of palm resources and safeguard their long-term viability.
