Since relatively few studies of the decomposition of vertebrate remains have examined the microfaunal members of the soil food web that function as secondary consumers, specifically nematodes, the goal of the current project was to catalog decomposition-induced nematode succession and changes to alpha, beta, and functional diversity, identifying potential indicator taxa associated with decomposition progression.
Nematodes are often used as indicators of enrichment in other systems, and initial observations from vertebrate decomposition zones have indicated there is an effect on nematode communities. In the current study, six adult beaver (Castor canadensis) carcasses were allowed to decompose in a forest ecosystem for 1 year. During this period, soil temperature, moisture, and electrical conductivity were monitored. Soils samples were taken at two depths to assess nematode community dynamics: 30-cm cores and 1-cm interface samples. Nematode abundance, alpha, beta, and functional diversity all responded to soil enrichment at the onset of active decay, and impacts persisted through skeletonization. After 1 year, nematode abundances and alpha diversity had recovered to original levels; however, both community membership and functional diversity remained significantly altered. identified Seven indicator taxa were identified that marked major transitions in decomposition progression. Enrichment of Rhabditidae (B1) and Diplogasteridae (B1), coupled with depletion in Filenchus (F2), characterized active and advanced decay prior to skeletonization in both cores and interface soils. Enrichment of Acrobeloides (B2), Aphelenchoides (F2), Tylencholaimidae (F4) and Seinura (P2) occurred during a narrow period in mid-skeletonization (day 153). Thus, this study has documented soil nematode successional patterns during vertebrate decomposition and has identified organisms that may function as indicator taxa for certain periods during decomposition. (publisher abstract modified)