Ethnobotanical utilization, local vulnerability, and soil-driven distribution of medicinal plants across disturbed and protected landscapes in Daura Emirate, Nigeria

Abstract

This study assessed the distribution, indigenous utilization, vulnerability, and conservation status of medicinal plants across cropland, rangeland, and forest reserve ecosystems in the Daura Emirate, Katsina State, Nigeria. A mixed-methods ethnobotanical and ecological approach was employed, integrating structured questionnaires, semi-structured interviews, field surveys, and soil analysis. A total of 150 respondents contributed 616 medicinal plant records across five Local Government Areas. Data were analyzed using descriptive statistics, alpha diversity indices, Sorenson similarity index, and Principal Component Analysis (PCA). Results revealed that croplands recorded the highest number of medicinal plant records (217), followed by rangelands (205) and forest reserves (194), indicating significant utilization of human-modified landscapes for traditional healthcare. The most frequently cited species included Guiera senegalensis, Bauhinia reticulata, and Azadirachta indica, primarily used in treating fever, malaria, wounds, and gastrointestinal ailments. Alpha diversity analysis showed high species diversity in croplands (Shannon = 4.697; Simpson = 0.9889), while forest reserves exhibited lower diversity but higher evenness. Sorenson similarity indices indicated moderate species overlap among land-use types, with the highest similarity between forest reserve and rangeland (0.512). PCA revealed distinct clustering of plant communities according to land use, explaining nearly all observed variance in species distribution. Soil analysis indicated higher organic carbon and organic matter in forest soils compared to croplands and rangelands, suggesting a strong link between soil fertility and medicinal plant distribution. Several low-frequency species were identified as potentially vulnerable due to habitat disturbance and overharvesting. The study highlights the dual role of agricultural landscapes in conserving medicinal plant diversity and the increasing vulnerability of forest-dependent species. It underscores the need for community-based conservation strategies, sustainable land management, and systematic documentation of indigenous knowledge to ensure long-term preservation of medicinal plant resources in semi-arid ecosystems.