摘要
为查明沙漠区CO2浓度和对大气CO2的影响以及在全球碳循环中的作用,利用红外CO2监测仪,在2009年5月对全球最高大的巴丹吉林诺尔图东大沙山等进行了17个钻孔CO2浓度的昼夜观测。结果表明,巴丹吉林大沙山不同观测点CO2浓度差异较大,各观测点CO2浓度变化在0.01%～0.075%之间;夜间沙层CO2浓度低,白天CO2浓度高;CO2浓度昼夜变化明显,从早7时到次日7时1～5m各深度CO2浓度均呈现由低到高再到低的变化规律;在24h内,沙层CO2浓度变化存在4个转折点,分别出现在凌晨5时、11时、18时和21时左右。在沙层水分一定的条件下,昼夜温度变化是造成沙层CO2浓度昼夜规律变化的主要原因,两者呈正相关关系;含水量较高的沙层CO2浓度明显高于含水量较低的沙层;5m深度以上沙层CO2浓度均高于地表空气CO2浓度,表明极端干旱的高大沙山区是CO2的来源区,也指示环境恶劣的裸露高大沙山区微生物活动产生的沙层CO2浓度仍然超过了大气CO2浓度。
In order to find out the concentration of CO2 in the desert area,its influence on the CO2 in the atmosphere and the role that it plays in the global carbon cycle,the research team utilized infrared monitor of CO2 to observe the concentration of CO2 of the 17 drill holes day and night in May 2009 in the highest desert area in Badain Jaran in the world.Results show that the difference of various observation spots＇ concentration of CO2 in the desert area in Badain Jaran is relatively big.The concentration of CO2 at each observation spot changes from 0.01% to 0.075%,and the concentration of CO2 at night is low but high in the daytime.The diurnal variation of concentration of CO2 in the desert area in Badain Jaran is obvious,and from 7 am to 6 pm,the concentration of CO2 at different depths ranging from 1 m to 5 m presents the regularity that it changes from low to high,and then from high to low.During 24 hours,four turning points are observed in the concentration of CO2,and they appear at 5 am,11 am,18 pm and 21 pm.Under the condition of unchanged water content of sand layer,the diurnal variation in temperature is the main reason for the change of the concentration of CO2 in the sand layer,and the diurnal variation in temperature is positively correlated with the diurnal variation of concentration of CO2 in the desert area.The sand layer＇s concentration of CO2 with higher water content is obviously higher than that with lower water content.Concentration of CO2 above 5 m in the desert area is higher than that above the surface,which indicates that the highest desert area where the CO2 comes from is also the source of CO2 in the atmosphere,and the sand layer＇s concentration of CO2 is generated from the activities of germs in the naked high large desert area with nasty environment.
出处
《地理研究》
CSCD
北大核心
2010年第11期1993-2003,共11页
Geographical Research
基金
教育部"长江学者"特聘教授项目(801813)
关键词
沙漠CO2浓度
昼夜变化规律
CO2排放
影响因素
最高沙山
巴丹吉林
the CO2 concentration in the desert
the diurnal variation laws
influencing factors
the highest desert area
the emission of CO2
