Traditional markets as indicators of wild plant diversity and availability under land use change in Central Sumatra

Wild plants play an important role in the daily practices of local communities. However, modernisation and rapid habitat alteration in Central Sumatra (Indonesia) threaten local knowledge associated with these resources. We investigated wild plant diversity, distribution patterns, and the socio-ecological factors shaping plant composition across 58 traditional markets in Riau, Indonesia. Using semi-structured interviews ( n = 195) and multivariate ordinations, we assessed species composition in relation to ethnic usage, land-use types, and environmental gradients. During the study, we recorded 172 plant species, alongside 5 fungi and 1 lichen, with food plants comprising the largest use category (54.1%). None of the traded species are legally protected, although several key taxa (e.g., Litsea elliptica ) showed high risk values, indicating potential decline in their availability in the market trade. Markets were clustered geographically into three groups: the capital city, eastern, and western regions, reflecting differences in socio-ecological conditions and ethnic diversity. Markets surrounded by monoculture plantations of oil palm, had significantly lower species richness and greater compositional homogeneity than those in mixed-agricultural and inhabited areas. Our findings indicate that landscape and cultural diversity both shape wild plant diversity in traditional markets. In particular, the expansion of monoculture plantations is associated with lower plant diversity, highlighting the importance of conserving natural habitats for sustaining biocultural diversity and food security.