关键词: 黄土高原, 气候变暖, 胡麻, 生育, 水分利用效率

Abstract: A gnotobiotic microcosm experiment was conducted to study the interactions between bacteria?feeding nematode Caenorhabditis elegans and bacterium Bacillus subtilis,and their effects on soil nitrogen mineralization at different Caenorhabditis elegans density.The results showed that the inoculation of the nematode stimulated the growth of the bacterium,and the increment was in order of 20>10>40 nematodes·g^-1 dried soil.The interaction between Caenorhabditis elegans and Bacillus subtilis significantly enhanced soil respiration rate and soil invertase,urease and phosphatase activities,with no significant differences among three test nematode densities.The inoculation of bacterial?feeding nematode markedly increased soil NH₄⁺-N and mineral N,suggesting that soil N mineralization was enhanced under the effect of the nematode.The increment of soil nitrogen mineralization at different nematode density was also in the same order mentioned above.

Key words: Loess Plateau, climate warming, oil flax, growth, water use efficiency