摘要
本文根据NaOH溶液吸收CO2 的原理 ,对西安长延堡春季土壤CO2 释放量进行了观测 ,对土壤CO2释放规律及其影响因素进行了探讨。资料表明 ,从春季的 3月到 5月 ,不同植被下土壤CO2 释放量均呈增加的趋势 ;植被对土壤CO2 释放量有一定影响 ,植被发育好 ,土壤CO2 释放量大 ;从当日早晨到次日早晨 ,土壤CO2 释放量呈现由低到高再到低的变化规律 ;土壤CO2 释放量变化相对于气温的变化具有滞后性 ,表明土壤CO2
On the basis of the principle of which CO 2 is absorbed by the solution of NaOH, the release amount of CO 2 from soils under different vegetation was observed round the clock in Changyanbao of Xi'an, and study the release amount of CO 2 and its change law as well as the factors affecting the release of CO 2 . The observed material shows that the release amount of CO 2 in 24 hours from March to May per square metre is between 900 and 4500mg from grassland, and is between 1 000 and 5 200mg from forest land. The release amount of CO 2 from soils under different vegetation is increased from March to May, which indicates that the release amount of CO 2 is much when temperature is high. The release amount from different soils changes from low to high and then to low from morning to the next morning. By comparing the curves of air temperature change with the curves of the release amount curves of CO 2 , it is known that the time stage of much release amount of CO 2 is corresponding to that of low temperature, and the time stage of less release amount of CO 2 is corresponding to that of high temperature. The reason why the phenomenon occurs is that the change of soil temperature is about 4～6 hours later than change of the air temperature. This shows that the change of the release amount of CO 2 from soils is determined by soil temperature. The release amount is much when the soil temperature is high and is less when the soil temperature is low. There is the difference of the release amount of CO 2 from the soils under different vegetation. The release amount of CO 2 from forest land is more than that from grassland, and the latter is more than that from exposed land. Vegetation play a part in affecting the release amount of CO 2. The vegetation develops well and produce much organic substance, which is favourable to the living of microorganism and producing of much CO 2. The release amount from forest land and grassland in night takes about 70% in day and takes about 30%. The release amount of CO 2 in exposed land in night is slightly greater than that in day.
出处
《干旱区地理》
CSCD
北大核心
2002年第3期208-213,共6页
Arid Land Geography
基金
科技部社会公益专项基金项目 (2 0 0 0 -164 )
国际地质对比计划项目 (IGCP44 8)
中国科学院黄土与第四纪地质国家重点实验室项目 (SKLLQG0 0 0 7)
国土资源部岩溶动力学开放实验室项目研究成果
