Showing papers by "Robert C. Venette published in 1995"
TL;DR: Observed differences in thermal adaptation may contribute to the predominance of species in the nematode community at different times during the year or at different depths in the soil.
Abstract: By grazing on bacteria, bacterial-feeding nematodes participate in decomposition food webs and N mineralization to an extent determined by metabolic and behavioral attributes and by life history. We studied the respiratory and metabolic activities of 8 species of bacterial-feeding nematodes at 5 temperatures by measuring the rate of CO2 evolution with an IR gas analyzer. We developed a method for determining size- or stage-specific respiration rates from measurements made on populations of varied stage-structure. Species from a single field site exhibited different thermal optima and temperature-niche breadths for respiratory and metabolic activity. Respiration rates of adults ranged between 1.25–8.80 nl O2 h−1 at 20°C among the species. Metabolic rates of adults ranged from 1.15 nl O2 μg(fresh wt)−1 h−1 for Rhabditis cucumeris Andrassy to 4.43 nl O2 μg(fresh wt)−1 h−1 for Bursilla labiata Andrassy at 20°C. At each temperature, metabolic rates of nematodes of similar size varied with thermal adaptation of the species. Metabolic rates of Cruznema tripartitum Zullini and Cephalobus persegnis Bastian were more sensitive to temperature change than were those of Acrobeloides bodenheimeri Thorne, A. buetschlii Steiner and Buhrer and Panagrolaimus detritophagus Fuchs. C. persegnis exhibited the greatest total metabolic activity cross a range of temperatures, and P. detritophagus the least. Observed differences in thermal adaptation may contribute to the predominance of species in the nematode community at different times during the year or at different depths in the soil.
59 citations