The effects of burning, mowing, and nitrogen (N) and phosphorus (P) fertilization on the trophic structure of a tallgrass prairie nematode community were examined in a long-term field experiment established in 1986. Nematode densities and trophic composition were determined in October of 1987, 1989, and 1994 following 2, 4, and 9 years of treatment, respectively.
To examine the effects of burning, mowing, and nitrogen (N) and phosphorus (P) fertilization on the trophic structure of the tallgrass prairie nematode community.
Composite soil samples consisting of four 5 cm diameter × 20 cm deep cores were collected in a systematic pattern from each plot in October of 1987, 1989, and 1994, following peak plant biomass production. To differentiate effects due to treatment per se from those due to changes in plant species composition which resulted from treatment, a second set of soil samples, with sampling restricted to the rhizosphere of A. gerardii, was collected in October 1989. Nematodes were extracted from 100 cm 3 subsamples using a modified Christie-Perry technique (Christie and Perry, 1951). Nematode counts were adjusted for extraction efficiency as determined by repeated extractions of selected samples. Extracted nematodes were identified to genus and assigned to one of the following trophic groups based on information summarized by Yeates et al. (1993b): (1) herbivore (root-feeding); (2) fungivore (hyphal-feeding); (3) microbivore (bacterial- and unicellular eucaryote-feeding); (4) predator (invertebrate-feeding); (5) omnivore (primarily invertebrate-feeding). In view of conflicting observations on the feeding habits of the Tylenchidae (root vs. fungal feeding; Yeates et al., 1993b), which represents a large component of the nematode community in tallgrass prairie, this family was analyzed separately from obligate herbivore taxa (sensu Yeates et al., 1993a). Conversely, since the major omnivorous nematodes in tallgrass prairie (represented by genera of the Dorylaimida) are primarily predaceous, these two trophic groups were combined for analysis (sensu Sohlenius et al., 1988). The dominant tallgrass prairie nematode taxa associated with each trophic group have been reported in an earlier publication (Seastedt et al., 1987). A list of nematode species native to tallgrass prairie can be found in Orr (1965).
For additional metadata information see: http://lter.konza.ksu.edu/sites/default/files/DC.pdf
For additional methods information see: http://lter.konza.ksu.edu/sites/default/files/MM.pdf