温度与土壤水分对有机碳分解速率的影响

Effects of temperature and soil moisture on soil organic carbon decomposition.

试验研究温度与土壤水分对有机碳分解速率的影响,结果表明:相同水分条件下,培育初期(1～20d)各处理CO2排放速率较高,相对值表现为35℃处理>25℃处理>15℃处理>5℃处理;随培育时间延长(>20d),CO2排放速率渐趋平稳。相同温度条件下,30%～90%田间持水量时培育初期(1～20d)各处理CO2排放速率初始值较高,之后降低,当趋于某一定值时,相对值大小随土壤水分含量增加而增加。相同温度与土壤水分条件下,CO2排放速率相对值大小随土壤有机碳含量增加而增加。

The incubating experiment was conducted to study the effects of temperature and soil moisture on decomposition of soil organic carbon in black soil with different organic carbon contents. The results show that under the same soil moisture, the CO2 releasing rate is high at the beginning of the incubation（0- 20d）, and the relatively released CO2 amount is elevated as temperature increasing. After that （ 〉 20d）, the CO2 releasing rate is gradually becoming stable. Under the same temperature and 30 % -90 % of field capability, the CO2 releasing rate is high at the beginning of the incubation （0 - 20d）, and then decreases. And the relatively released CO2 amount is elevated as soil water content increasing. Under same temperature and soil water condition, the CO2 releasing rate is enhanced as the organic carbon contents increasing.