锡林浩特草原CO_2通量特征及其影响因素分析  

Observing characteristics of CO_2 flux and its influencing factors over Xilinhot grassland

作　　者：汪文雅 郭建侠[2] 王英舜[3] 武魁[3] 

机构地区：[1]南京信息工程大学,南京210044 [2]中国气象局气象探测中心,北京100081 [3]锡林浩特国家气候观象台,内蒙古锡林浩特026000

出　　处：《气象科学》2015年第1期100-107,共8页Journal of the Meteorological Sciences

基　　金：公益性行业(气象)科研专项(GYHY201106049);中国气象局气候变化专项(CCSF2011-23)

摘　　要：利用锡林浩特国家气候观象台开路涡度相关系统、辐射土壤观测系统,测得的长期连续通量观测数据,对锡林浩特草原2009—2011年期间的CO2通量观测特征进行了分析。结果表明:CO2通量存在明显的年际、季节和日变化特征。3 a中NEE年际变率达到200 g·m-2,季节变率最大达到460 g·m-2,日变化幅度生长季最大达到0.25 mg·m-2·s-1。通过不同时间尺度碳通量与温度、水分、辐射等环境因子的分析,认为CO2通量日变化主要受温度和光合有效辐射影响,而季节变化和年变化主要受降水和土壤含水量的影响。降水强度及时间分布是制约牧草CO2吸收的关键因素,大于15%的土壤含水量有利于促进牧草生长。Based on the continuous measurement of surface fluxes data by eddy covariance during 2009-2011 from Xilinhot National Climatological Observatory, the characteristics of CO_2 flux and its in- fluencing factors were investigated. Results show that diurnal, seasonal and annual variation characteris- tics of CO_2 flux are obvious. The annual variation rate in three years of NEE reaches 200 g· m^-2, the max- imal seasonal one amounts to 460 g· m^-2, and the maximal daily variation amplitude in growth seasons is 0. 25 mg·m^-2·s^-1. Analysis on carbon fluxes and meteorological factors such as temperature, water and radiation at different time scales shows that daily variation of CO_2 flux is mainly affected by temperature and photosynthetically active radiation （PAR） , while annual and seasonal variations are chiefly influ- enced by precipitation and soil moisture content. The intensity and time distribution of precipitation are the key factors to CO_2 flux. Soil water more than 15% will promote the growth of herbage.

关 键 词：CO_2通量 影响因子 锡林浩特草原 

分 类 号：P404[天文地球—大气科学及气象学]