Effects of Temperature on Population Growth and N Mineralization of Soil Bacteria and a Bacterial-feeding Nematode

Abstract

Effects of temperature on the population growth of soil bacteria, P. fluorescens and B. subtilis, and a bacterial-feeding nematode, C elegans, and their activities for N mineralization were studied in gnotobiotic microcosms at 15, 20 and 25°C. Nematode densities increased significantly with temperature. Inoculation of nematodes significantly increased bacterial densities of both P. fluorescens and B. subtilis at 20 and 25°C. Bacterial and nematode densities rose simultaneously. The amounts of NH4+-N were significantly greater in the microcosms with nematodes and bacteria than the microcosms with bacteria alone at 20 and 25°C. There were significant interactions between temperature, nematodes and bacterial populations. These results indicate that nitrogen mineralization was closely related to the population dynamics of the nematodes and bacteria. © 2001, Japanese Society of Microbial Ecology & The Japanese Society of Soil Microbiology. All rights reserved.