重庆市缙云山3种森林类型的土壤呼吸特征研究  

Soil Respiration Characteristics of Three Forests in Jinyun Mount of Chongqing City

作　　者：冯华敏[1] 王玉杰[1] 王云琦[1] 雷声坤[1] 刘春霞[1] 周彬 

机构地区：[1]北京林业大学水土保持学院水土保持与荒漠化防治教育部重点实验室,北京100083 [2]重庆缙云山国家级自然保护区管理局,重庆400700

出　　处：《水土保持通报》2011年第5期38-44,共7页Bulletin of Soil and Water Conservation

基　　金：林业公益性行业科研专项"森林生态系统碳氮水耦合观测;模拟与应用技术"(201104009-03);林业公益性行业科研专项"长江三峡库区典型森林植被对水资源形成过程的调控研究"(201104005-01)

摘　　要：2010年7—12月,采用LI—COR公司生产的LI-8100土壤碳通量测量系统及土壤温度、湿度传感器对重庆市缙云山自然保护区内的毛竹林、针阔混交林、针叶林的土壤呼吸速率以及地表下5cm处的土壤温度和体积含水量进行测定,最后对3种林地土壤呼吸的时间变化特征及其与土壤温湿度和森林凋落物的关系进行了分析。结果表明:(1)3种林地土壤呼吸速率日内变化特征不明显,白天总体呼吸速率大于夜间。(2)月际变化明显,表现为从7—8月土壤呼吸速率增大,8—12月逐渐减小。3种林分7—12月总体平均土壤呼吸速率表现为毛竹林>针阔混交林>针叶林。(3)毛竹林、针阔混交林、针叶林的土壤呼吸速率与5cm土壤温度均存在极显著的指数相关关系(p<0.01),温度每升高10℃,土壤呼吸的变化比率Q10值分别为2.67,2.19,2.13。(4)土壤呼吸特征与5cm土壤含水量之间没有明显的相关关系。(5)各林地无凋落物的土壤呼吸速率均小于对应林地有凋落物土壤呼吸速率,各林地无凋落物的Q10值均大于对应林地有凋落物的Q10值。A field study was conducted in Jinyun Mountain Nature Reserve,Chongqing City from July to December in 2010.A LI-8100 soil carbon flux measurement system（LI—COR） was employed to measure soil respiration rates（SRRs） in bamboo,mixed wood and coniferous forests.In addition,soil temperature and volumetric water contents were measured at 5 cm below ground.By analyzing temporal change characteristic of SRR and its relationship with soil temperature,moisture and litter,the results indicate that no obvious diurnal variation of SRR was found in all the three forests.SRRs during day time were greater than those at night.SRR changed significantly monthly： it gradually increased from July to August and decreased from August to December.The average SSRs during experiment period in the three forests exhibited a decreasing order as bamboomixed woodconiferous.The SRRs of the three forests were closely correlated with soil temperature（p0.01）,with Q10 values（the ratio of soil respiration change whenever the temperature increase 10 ℃）2.67,2.19 and 2.13 respectively.Conversely,the SRRs were not significantly correlated with soil water contents.In addition,the SRRs of all forests without litter cover were smaller than those with litter,indicated by the greater Q10 values found in the forests without litter.

关 键 词：三峡库区 土壤呼吸速率 土壤温度 土壤湿度 凋落物 

分 类 号：S154.1[农业科学—土壤学]