Ethnobotanical study on wild edible plants in The Kuancheng Traditional Chestnut Eco-Planting System, a globally important agricultural heritage system in Hebei, China

Globally Important Agricultural Heritage Systems (GIAHS) are living agroecosystems shaped by the coevolution of traditional knowledge (TK) and agrobiodiversity. As a core GIAHS criterion, agrobiodiversity should be assessed beyond crops and livestock to include wild resources that communities regularly use and manage. Wild edible plants (WEPs) and associated TK that guide their identification, harvesting, processing, and habitat care are therefore a key but poorly documented part of agrobiodiversity in the mountainous regions of northern China. The Kuancheng Traditional Chestnut Eco-Planting System (KTCES) in Hebei Province, northern China, is a chestnut-based GIAHS with great diversity and value of WEPs. Along with the rapid economic development and fast reduction of TK, it is necessary to document WEPs and associated TK in KTCES, both to contribute to the conservation of agrobiodiversity and to provide a reference for the sustainable development of GIAHS. From February 2024 to July 2025, ethnobotanical surveys were conducted in six townships of Kuancheng Manchu Autonomous County, Hebei, China. The investigation methods include free listings, semi-structured interviews, key informant interviews and participatory observations. A total of 124 respondents were interviewed. Information was collected on the edible parts, categories, consumption methods, and multiple uses of WEPs. The cultural significance of these plants was assessed by calculating the relative frequency of citation (RFC) and the cultural food significance index (CFSI). A total of 87 species of WEPs belonging to 37 families and encompassing various categories, such as wild vegetables (67), wild fruits (16), spices (10) and nuts (3), were documented in this study. The primary parts utilized include tender leaves, fruits, roots, seeds, and flowers, with harvesting predominantly taking place in spring and summer. The most frequently used families were Asteraceae (20), Rosaceae (9), Fabaceae (6) and Amaranthaceae (5). On the basis of the CFSI and RFC values, 30 species were identified as the most significant in local dietary culture, including Gypsophila oldhamiana , Leptopus chinensis , Indigofera kirilowii and Ziziphus jujuba var. spinosa and so on. KTCES possesses abundant WEPs resources, and local residents possess a wealth of TK related to WEPs utilization. The diverse ways in which WEPs are used form the foundation for regional ecological adaptation and cultural identity. High-value WEPs have driven local economic development, ecological protection, and cultural innovation. It is necessary to investigate, document, and preserve WEPs and associated TK in GIAHS, as they hold particular significance for the conservation of agrobiodiversity and GIAHS.