Integrating local ecological knowledge, functional ecology and conservation strategies of wild loquat (uapaca kirkiana müll. arg.) in Malawi

Abstract

Uapaca kirkiana Müll. Arg. is an indigenous fruit tree of Malawi’s Miombo woodlands that provides vital nutritional, economic, and ecological services. Despite its crucial importance to the ecosystems, its populations are declining due to overharvesting, unsustainable pruning, habitat loss, charcoal production, wildfires, and climate change. Its decline is a huge threat to both livelihoods and ecosystem functioning. Despite its importance, limited integrated understanding exists of its ecological, functional, and socio-economic dynamics across Malawi, which constrains sustainable management and conservation planning. This study aimed to analyse local ecological knowledge, ethnobotanical uses, and community-based conservation strategies of U. kirkiana in Malawi, characterize woody species composition and phylogenetic structure along elevation gradients associated with U. kirkiana, quantify intraspecific functional trait variation of U. kirkiana across eco-geographical regions and its relationship with environmental gradients, evaluate population structure, regeneration dynamics, and carbon storage potential of U. kirkiana across geographic regions and model the current and future distribution of U. kirkiana under climate change scenarios. Understanding these aspects is essential to inform sustainable conservation strategies, enhance livelihoods, and maintain ecosystem services. The methods in this study included a stratified survey of 1,222 households to capture local ecological knowledge, conservation practices, species use and perceived vulnerability. Forest inventories were conducted in six forests across the country, with two forests per region, assessing 149 plots and 72 trees for 21 morphological and functional traits. Taxonomic and phylogenetic diversity, diameter distributions, and community structure were analyzed, while trait variability was assessed using mixed-effects models, discriminant and redundancy analyses and hierarchical clustering. Species distribution modeling employed MaxEnt and habitat prioritization used Zonation. The results indicated widespread recognition of population decline, varying by region, profession and education. Deforestation and charcoal production were the main threats, whereas agroforestry, cutting prohibition, regeneration protection and pruning restrictions were key conservation measures. Fruits, trunks, and branches were most utilized for food, firewood and medicine. A vulnerability index of 2.25 reflected moderate risk. Four morphotypes indicated adaptive differentiation across environmental gradients, while small diameter classes dominated populations, suggesting active regeneration but overharvesting of large trees. Phylogenetic diversity and community assembly varied with elevation, mainly influenced by temperature. Structurally, U. kirkiana populations were dominated by small diameter classes (10-20 cm), with few mature individuals (>45 cm), indicating regeneration disturbance. Diameter at breast height (DBH) was positively correlated with the structural quotient (Qs) and inter-tree distance, but negatively correlated with diameter differentiation, suggesting low heterogeneity in mature stands. U. kirkiana tolerated mixed-species stands (mingling index: 20-44%), supporting its suitability for agroforestry systems. The Northern region had the highest carbon storage (57.80 tCO₂/ha), significantly higher than the Southern (51.25tCO₂/ha) and Central (43.80 tCO₂/ha) regions (p < 0.05), because this region is characterized by greater annual rainfall (>1,600 mm), which supports better tree growth and biomass accumulation. The estimated economic value of U. kirkiana was MWK 1,011,997.57 (577.95 USD/ha). The current distribution indicates that only 9% of habitats are suitable for U. kirkiana. Future projections suggest a decline in its range (from 9% to 6%), with a shift toward higher altitudes in the northern and central regions. Temperature emerges as a key factor determining its distribution, emphasizing the importance of strategies such as assisted migration, domestication, and climate-adapted plantations. Overall, U. kirkiana is a multifunctional species facing moderate anthropogenic and climate threats. Integrating LEK and functional ecology with climate models provides a more robust and socially relevant conservation framework than any single method.