Soil arthropods as indicators: Biodiversity responses across conventional, ecological and natural systems in an oceanic island

Soil arthropod communities are key indicators of agroecosystem sustainability, yet their responses to different management practices remain understudied in oceanic islands. This study evaluates soil arthropod diversity, community structure, and composition across three ecological zones of Tenerife (Canary Islands, Spain), each including an ecological and a conventional agroecosystem, along with a natural reference site. Employing a combination of hypogean fauna pitfall trapping and taxonomic identification, we analyzed communities at five soil depths (0–75 cm). Results show that ecological management fosters communities resembling natural vegetation more closely than conventional systems in laurel forests and thermo-sclerophyllous woodlands, but not in spurge shrublands. Patterns were variable, with conventional systems occasionally supporting higher abundance and richness (e.g., 5922 individuals in conventional vs. 2100 in natural vegetation in laurel forests), albeit dominated by few taxa. Key taxa such as Diplura highlighted management-specific responses, while depth-dependent trends revealed significant surface layer impacts, with the highest dissimilarities at 0–15 cm (0.62 in laurel forests and thermo-sclerophyllous woodlands). Coleoptera analyses further demonstrated that natural vegetation supports a higher richness of endemic and native species (e.g., 23 endemics in laurel forests), while conventional systems are characterized by the abundance of introduced taxa (e.g., 31% of individuals in conventional laurel forests). Despite the potential of ecological practices to enhance biodiversity, natural vegetation remains irreplaceable for conserving endemic and native arthropods. These findings underscore the relevance of soil arthropods as indicators of sustainable land use and the need for agroecological strategies tailored to local contexts to maximize biodiversity conservation. • Soil arthropod communities differed across land-use types and ecological zones • Conventional agriculture soils hosted arthropod communities with lowest evenness • Strongest effects of agriculture on arthropods usually occurred in topsoil (0–15 cm) • Introduced beetles increased from natural to ecological, peaking in conventional