Nematodes as indicators of soil health

Soil nematode communities are composed of both plant-parasitic and beneficial taxa, and are distributed across five trophic groups within the soil food web. These nematodes contribute up to 12% of nitrogen mineralization, making them valuable indicators of ecosystem function. Ecological succession and food web complexity indices are useful for detecting the effects of management practices such as cultivation, fertilizer use, pollutants, and pesticide application. These indices are derived from the abundance of nematodes categorized by their trophic group and colonizer-persister (cp) characteristics. However, future research is needed to empirically validate these cp assignments which are often inferred based on morphology alone. Identifying sentinel taxa that respond consistently to specific types of disturbance would further enhance the interpretation of results and reduce the ambiguity caused by certain taxa. Customizing sentinel taxa to specific ecoregions and ecosystems would also improve molecular diagnostic kits, making it easier for non-specialists to employ nematode indicators on large geographic scales.