Soil nematode communities as indicators of forest ecosystem health: A study in Patnitop region of District Udhampur, UT, J&K, India

Nematodes are vital bioindicators of soil health, reflecting ecological conditions and anthropogenic disturbances, such as tourism. This study provides the first comprehensive assessment of nematode diversity in the Patnitop forest (Jammu & Kashmir, India), evaluating their community structure and ecological significance. Soil samples were collected from multiple forest sites, with nematodes identified to genus level and classified by trophic groups and colonizer-persister (c-p) classes. Diversity indices (Shannon Index, Species Evenness, Maturity Index, Plant Parasitic Index) and ecological indices (Enrichment, Structure, Basal) were computed to assess soil food web conditions. Statistical analysis employed the Kruskal-Wallis test. We identified 37 nematode genera, with bacterivores dominating (58.7%), followed by omnivores (20.58%), herbivores (11%), predators (8.9%), and fungivores (2.7%). The c-p classification showed high proportions of opportunistic c-p 1 nematodes (39.0–48.1%) and stable c-p 4 (19.3–27.6%) and c-p 5 (5.8–15.3%) groups. Moderate diversity (Shannon Index: 1.93; Evenness: 0.73) and nutrient-rich conditions (Maturity Index: 2.50; Plant Parasitic Index: 3.20) were observed. High Enrichment (82.59) and Structure (92.48) indices, combined with a low Basal Index (4.17), indicated a stable food web under minimal stress. Trophic group differences were statistically significant (p = 0.00129). The predominance of bacterivores highlights bacterial-mediated decomposition, while nematode metrics demonstrated sensitivity to ecological gradients, underscoring their utility as bioindicators for tourism-linked disturbances. These findings advocate integrating nematode monitoring into forest management frameworks to guide soil conservation in this fragile ecosystem.