温度和土壤水分对祁连山青海云杉林土壤呼吸的影响  

Influence of Temperature and Soil Moisture on Soil respiration of Picea crassifolia in Qilian Mountains

作　　者：彭家中[1] 常宗强[1] 冯起[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所寒旱区流域水文及应用生态实验室,兰州730000

出　　处：《干旱区资源与环境》2008年第3期165-169,共5页Journal of Arid Land Resources and Environment

基　　金：中国科学院创新团队国际合作伙伴计划(CXTD-Z2005-2);国家科技部"重大基础研究前期研究专项"(2005ccA05200);国家自然科学基金项目(40501012)共同资助

摘　　要：采用美国Li-cor公司生产的LI6400-09土壤呼吸室和LI6400便携式光合作用测量系统对祁连山云杉林土壤呼吸速率进行野外测定,并通过多元回归对其影响因子进行了分析。结果表明：土壤呼吸总体趋势是夏季高,其它季节低,但季节动态呈现不规律的多峰曲线;气温、地表温度以及5cm、10cm、15cm和20cm的土壤温度均与土壤呼吸速率呈显著的指数关系,温度对土壤呼吸的影响在低温时比高温时更显著;土壤呼吸的平均速率为2.145μmol.m^-2·s^-1。以气温、地表温度以及5cm、10cm、15cm和25cm的土壤温度为依据得到的Q10值依次为2.67、2.23、4.17、4.32、4.36和4.54;0-10cm和10-20cm土层的土壤含水量均与土壤呼吸速率呈相关关系,当土壤水分含量较低的情况下,随着土壤水分含量的增加,土壤呼吸速率也随着增加,但是当土壤水分含量增加到一定程度时,土壤呼吸速率则表现出降低的趋势。This one-year study of CO2 evolution from different type of vegetation soil using a LI6400-09 soil chamber connected to a LI6400 portable photosynthesis system in Qilian Mountains,examines seasonal trends and CO2 efflux in relation to biomass and climatic factors.The seasonal pattern of CO2 efflux was irregular,though the rate of CO2 evolution was greater in summer than in other seasons.Significant relationships were found between CO2 evolution rate,ambient air temperature and soil temperature（the surface,5cm depth,10cm depth,15cm depth and 20cm depth,respectively）,which could be best described by exponential equations.The influence of temperature was more conspicuous at lower temperature than at higher temperature conditions.This was consistent with the results reported by other researchers.The mean soil respiration rate during the study period was 2.145μmol·m^-2·s^-1,and the calculated Q10 values based on air temperature and soil temperature at surface,5cm,10cm,15cm and 20cm depth were 2.67、2.23、4.17、4.32、4.36 and 4.54,respectively.Soil respiration rate was linearly correlated with soil gravimetric water content at 0-10 cm and 10-20 cm.

关 键 词：土壤呼吸 青海云杉林 温度 土壤水分 Q10 祁连山 

分 类 号：S152[农业科学—土壤学]