中文摘要：

测定了浙江慈溪5个不同利用年限水稻土（50～2000a）的微生物功能多样性、呼吸作用强度、硝化作用强度及产甲烷势，比较分析了水稻土主要微生物过程强度与利用年限的相关性,结果发现，2000a水稻土的单一碳源底物利用能力最高，而1000a水稻土的短期利用能力也明显高于50-700a的水稻土；随着利用年限的延长，水稻土微生物群落的Shannon指数、Simpson指数和McIntosh指数均趋于升高，利用年限相距500a以上的水稻土的碳源利用特性在主成分PCAl或PCA2上有较好的分离；随着利用年限的延长，水稻土的呼吸强度显著降低，硝化强度和产甲烷势也趋于下降．结果表明，水稻土在持续利用之后，微生物群落功能多样性得到一定加强，而一些调控温室气体排放的微生物过程强度明显减弱．

英文摘要：

The microbial functional diversity, respiration rate, nitrification activity and methane generation potential were investigated in five paddy soils in use for 50 a to 2000 a, and the correlations between microbial processes and field ages were estimated. The sole-carbon-source utilization （ SCSU ） activity was highest in the soil used for 2000 a, and the short-term SCSU activity in the soil used for 1000 a was higher than those in the soils used for 50 -700 a. The Shannon index, Simpson index and Mclntosh index of microbial community diversity increased with years of use. Microbial carbon utilization characteristics could be separated by PCA1 or PCA2 in soils with age differences of more than 500 a. The soil respiration rate decreased significantly with the increased number of years of use, and soil nitrification activity and methane generation potential also tended to decrease similarly. The results suggest that sustained utilization of paddy soil may increase microbial functional diversity, while decreasing some microbial processes related to greenhouse gas emissions.