中文摘要：

以江苏地区棉花生产主推品种泗杂3号为材料，模拟花铃期土壤短期渍水胁迫环境，研究渍水（3，6，9，12d）对不同土壤层次（0—20，2040cm）中土壤微生物数量、土壤酶活性、土壤养分含量及棉花生物量累积和产量形成的影响。结果表明，花铃期短期渍水显著抑制棉花株高伸长和生物量累积，减少单株铃数与单铃重，导致籽棉产量的降低。随渍水天数的增加，土壤速效氮含量显著降低，而土壤全氮与有机质含量出现一定程度的升高。渍水条件下，土壤真菌、放线菌数量呈明显的降低趋势，而细菌数量的降低幅度较为平缓。渍水导致土壤脲酶、转化酶以及磷酸酶活性显著降低，而促使土壤过氧化氢酶活性出现一定幅度的升高。除过氧化氢酶外，0～20cm土层土壤养分含量、微生物数量以及土壤酶活性显著高于20-40cm土层，且0—20cm土层中各指标的变化幅度较20-40cm也基本表现更为剧烈。由此可见，不同土壤层次中土壤微生物数量以及土壤酶活性对土壤渍水的反应均很敏感，且土壤养分有效性的降低将不利于棉花生物量累积与最终产量的形成。

英文摘要：

The experiment was completed in pool with Siza3 （popularized cultivar in Jiangsu province） at Pailou experiment station in Nanjing Agricultural University. By simulating the short-term waterlogging during the flowering and boll forming stage, set five water treatments including one well watering （soil rela- tive water content was （75＋5）~） and four waterlogging treatments （3, 6, 9, 12 days）, this study aimed to assess the effects of waterlogging on soil microbe quantity, enzyme activity, nutrient content of two soil lay ers （0--20, 20--40 cm） and the accumulation of cotton biomass and yield. The results showed that the growth of the cotton plant height and biomass accumulation were inhibited significantly by waterlogging dur- ing the flowering and boll forming stage, and resulted in the reduction of seed cotton due to the decrease of the number of boll per plant and boll weight. With increasing the waterlogging days, the content of soil or ganic matter and total nitrogen accumulated for a certain degree, while the available nitrogen content reduced significantly, the number of soil fungi and aetinomycetes had an obvious decreasing trend, while the variation of the number of bacteria was gentle. On the condition of waterlogging, soil urease, invertase and phospha- tase activities gradually decreased, while soil catalase activity increased in certain amplitude. Except catalase, soil nutrient content, the number of soil microbe quantity and soil enzyme activity in 0--20 cm layer was sig nificantly higher than that in 20--40 cm layer, and the variations of soil bio indicators in 0--20 cm layer were larger than that in 20--40 cm layer basically. In summary, the soil microbe quantity and soil enzyme activity of two layers were extremely sensitive to waterlogging, and the low soil nutrient availability was not condu- cive to the accumulation of cotton biomass and yield.