Heritage trees of Lingshui, China: Diversity, distribution, and conservation challenges

Heritage trees, as vital bioresources, enhance urban ecosystems and cultural heritage in Lingshui, Hainan, China. Yet, urbanization and environmental shifts threaten their persistence, necessitating detailed studies for conservation. From 2023 to 2024, the authors surveyed 133 heritage trees across 18 species, 14 genera, and 10 families. Tamarindus indica L. dominated (importance value 37.60), followed by Ficus microcarpa L. f. (14.37) and Bombax ceiba L. (12.55), comprising 64.52% of the total importance value. Diversity varied across twelve towns, with Yingzhou showing the highest despite fewer trees. Most trees, aged 100-150 years with 60-150 cm diameters, indicated an aging population. Kernel density mapping revealed central-eastern distribution hotspots, hinting at historical or environmental influences. Termite infestation (45.1%) and trunk decay (36.4%) were primary threats, with pests and diseases less impactful (6.8%). Compared to other Hainan cities, Lingshui’s lower tree diversity reflects topography, typhoons, and human pressures including urbanization and agriculture. Targeted conservation addressing biological and socioeconomic factors is critical to sustain these bioresources, which support biodiversity through microhabitats, ecological continuity, and genetic diversity in urbanizing landscapes.