Autecology and Soil Characteristics of Native Capparis spinosa L. in the Cyrenaica Region, Libya

Abstract

Capparis spinosa L. (caper) is a medicinal and aromatic plant of significant economic and ecological value, well-adapted to the Mediterranean basin's harsh environments. This study investigated the geographical distribution, ecological requirements, and associated soil characteristics of native C. spinosa populations in the Cyrenaica region of northeastern Libya. Field surveys were conducted at nine distinct sites representing the region's diverse ecology, from coastal plains to semi-arid interiors. At each site, plant presence was recorded, and soil samples were collected from the rhizosphere and analyzed for key physicochemical properties (pH, electrical conductivity (EC), and macronutrients). The results confirmed the wide distribution of C. spinosa across an elevational gradient (13-380 m a.s.l.) and its occurrence in a variety of habitats. Soil analyses revealed significant variations in properties across sites, with pH ranging from slightly acidic to slightly alkaline (6.50-8.15) and EC showing high variability (1.45-46.30 dS/m), particularly in coastal sites like La’thrun, indicating salinity tolerance. Nutrient levels (N, P, Ca, Mg) also varied considerably. One-way ANOVA indicated no significant difference in the combined soil measurement means across the sites (p > 0.05), suggesting the plant's broad edaphic tolerance. The plant's resilience in arid and semi-arid conditions underscores its ecological importance for soil conservation and combating desertification. This research provides a foundational scientific basis for the conservation, sustainable utilization, and potential cultivation of this valuable native resource in Cyrenaica.