[Effects of temperature on organic carbon mineralization in paddy soils with different clay content].
An incubation test with three kinds of paddy soil (sandy loam, clay loam, and silty clay soils) in subtropical region was conducted at 10, 15, 20, 25 and 30 degrees C to examine the response of the mineralization of soil organic carbon (SOC) to temperature change. The results showed that during the period of 160 d incubation, the accumulative mineralized amount of SOC in sandy loam, clay loam, and silty clay soils at 30 degrees C was 3.5, 5.2 and 4.7 times as much as that at 10 degrees C, respectively. The mineralization rate was lower and relatively stable at lower temperatures (< or = 20 C), but was higher at the beginning of incubation and decreased and became stable as the time prolonged at higher temperatures (> or = 25 degrees C). During incubation, the temperature coefficient (Q10) of SOC mineralization in test soils fluctuated, with an average Q10 in sandy loam, clay loam, and silty clay soils being 1.92, 2.37 and 2.32, respectively. There was a positive exponential correlation between SOC mineralization constant k and temperature (P < 0.01), and the response of SOC mineralization to temperature change was in the order of clay loam soil > silty clay soil > sandy loam soil.
Ren
Xiu-E
XE
Key Laboratory of Subtropical Agro-ecology, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China. renxiue2004@163.com
Tong
Cheng-Li
CL
Sun
Zhong-Lin
ZL
Tang
Guo-Yong
GY
Xiao
He-Ai
HA
Wu
Jin-Shui
JS
D002244:Carbon / Q000032:analysis*; D009930:Organic Chemicals / Q000032:analysis; D012275:Oryza / Q000254:growth & development*; D012987:Soil / Q000032:analysis*; D013696:Temperature
D009930:Organic Chemicals; D012987:Soil; D002244:Carbon