亚高山岩溶生态系统内土壤CO_2体积分数垂向差异分析——以金佛山为例

Variation about the Concentration of CO_2 in Soils with Different Karst Ecosystem in the Sub-mountain Region——A Case Study of Jinfo Mountain

利用CO2红外线分析仪对金佛山夏季垂直自然带上岩溶生态系统内的土壤CO2气体进行一个月的连续观测,研究土壤CO2体积分数的垂向差异.结果表明:山顶样点土壤CO2体积分数的月波动幅度大于西坡样点;山顶林地样点的土壤CO2体积分数高于裸地,低于西坡林地,而其裸地的土壤CO2体积分数则高于西坡裸地;岩溶区生态系统内剖面土壤CO2体积分数基本呈现出随深度增加而增大的单向梯度分布特征;林地土壤CO2体积分数最大梯度出现的深度大于裸地.

The concentration of soil CO2 in the sub-mountain region was observed continuously in a month in summer by utilizing CO2 infrared analyzer to depict the difference of soil CO2 between sub-tropic karst ecosystem and temperate karst ecosystem.The results obtained were as follows：（1） the variation of soil CO2 in summit was larger than that in west slope;（2） the value of concentration of soil CO2 in summit was higher in woodland than that in uncovered land,and lower than that in woodland of west slope;（3） the value of concentration of soil CO2 in uncovered land was higher in summit than that in west slope;（4） the values of concentration of soil CO2 increased with the depth,taking on a characteristic of unidirectional gradient distribution;（5） the position with maximal gradient of concentration of soil CO2 was deeper in woodland than that in uncovered land in sample plots.