Abstract: A pot experiment was conducted to study the variation in the soil microbial biomass carbon(C_mic),soil microbial biomass nitrogen(N_mic),soil respiration intensity,soil microbial metabolic quotient,soil enzyme activities,and chlorophyll content,proline content and peroxidase activity(POD) in rice leaf at different developmental stages under submerged conditions.The C_mic,N_mic and soil respiration activity significantly ascended at the early stage and then declined during rice growth,but ascended slightly again at maturity.Whereas soil metabolic quotient declined at all stages.Soil urease activity increased firstly and then decreased,but acid phosphatase and dehydrogenase activities descended first and then ascended,and descended again.Soil urease activity and acid phosphatase activity showed a peak value about 30 days after rice transplanting,but the peak value of dehydrogenase activity emerged about 50 days after rice transplanting and the three soil enzyme activities were significantly different at different developmental stages.As rice growing,chlorophyll content in rice leaf descended at the early stage then ascended sharply and a peak value appeared about 70 days after rice transplanting.POD activity increased gradually,but proline content declined gradually.It was suggested that soil biochemical characteristics was affected significantly by rice growth in the interaction system of the rice,soil and microorganisms.

Key words: rice, soil microbial biomass, soil metabolic quotient, soil enzyme activity, chlorophyll, proline, peroxidase

摘要： 研究了全生育期淹水栽培条件下，水稻不同生长阶段的土壤微生物生物量C、土壤微生物生物量N、呼吸作用强度、代谢商、土壤酶活性及水稻叶绿素、脯氨酸、过氧化物酶（POD）活性的变化特征。随着水稻生长，土壤微生物生物量C、土壤微生物生物量N、呼吸作用强度表现为先升后降，到成熟期有所回升的变化规律，且在水稻不同生育阶段差异显著，而土壤微生物代谢商一直下降。土壤脲酶活性表现为先升后降，而酸性磷酸酶与脱氢酶活性则表现为先降后升再降的变化规律。脲酶及酸性磷酸酶活性在水稻移栽后的30 d左右形成峰值，而脱氢酶活性则在50 d左右形成峰值，且在水稻不同生育阶段差异显著。随着水稻生长，水稻叶片中的叶绿素含量表现为先降后升的变化规律，在移栽后70 d左右形成峰值，然后急剧下降，POD的活性则表现为逐渐增强，而脯氨酸含量表现为逐渐下降，不过上述水稻生理指标与土壤各生物化学指标间不存在显著的相关性。试验结果表明在水稻土壤微生物相互作用的体系中，土壤微生物量和酶活性明显受到水稻生长发育的影响。

关键词: 水稻, 土壤微生物生物量, 土壤代谢商, 土壤酶活性, 叶绿素, 脯氨酸, 过氧化物酶