关键词: 硫, 重金属, 土壤, 植物解毒, 形态转化

Abstract: A gnotobiotic microcosm experiment was conducted to study the influence of bacterivorons nematodes (Protorhab-ditis sp. ) on bacteria (Pseudomonas fluorescens) population under different conditions including substrate concen-tration, oscillation pattern, and numbers of nematodes inoculated. When the bacteria were incubated under intermit-tent oscillation by hand (6 times at 0.5 h intervals, 22℃ ), their growth was stimulated in the presence of nema-todes, and the bacteria grew faster with the increase of nematode numbers and substrate (liquid potato-sucrose medi-um) concentration. However, when the incubation was under continuous oscillation (100 rpm, 22℃ ), bacteria pop-ulation was deflated with the addition of nematodes, and the inhibition was greater when a higher concentration of substrate was used. It was found that the stimulation or inhibition of bacteria population by nematodes occurred in the logarithmic stage of bacteria growth. The optimal and over-grazing of nematodes on regulating bacteria popula-tion was discussed.

Key words: sulfur, heavy metal, soil, phytodetoxification, speciation transformation.