Soil Nematode Communities as Environmental Indicators in Plantations and Natural Tropical Forests of Ecuador

Soil nematodes are fundamental components of terrestrial ecosystems and serve as sensitive bioindicators of soil health, yet their diversity and ecological functions in tropical forests remain underexplored. This study characterized nematode communities in natural forests and teak (Tectona grandis) plantations at two localities in Ecuador (“La María” and “La Represa”), evaluating abundance, diversity, and ecological indices. A total of 14,250 individuals were identified, with Meloidogyne (43.16%) and Pratylenchus (25.61%) as dominant families, followed by Mononchus (12.28%), while Dorylaimus and Rhabditis represented lower proportions (9.47%). Diversity indices indicated medium to high diversity (Shannon: 2.52–2.67) and high evenness, particularly in natural forests. The maturity index (MI) highlighted significant differences between systems, with higher values in natural forests (3.02–3.4) suggesting greater stability and lower disturbance compared to plantations (3.0–3.2), which reflected the prevalence of colonizer taxa. Despite higher abundance in plantations, natural forests supported more balanced trophic structures and greater ecological stability. These findings are consistent with global evidence that land-use intensification reduces soil biodiversity and trophic complexity. Overall, nematode communities in Ecuadorian tropical soils provide robust indicators of ecological integrity, emphasizing the importance of conserving natural forests and integrating nematode-based metrics into sustainable land management and restoration strategies in tropical regions