Soil CO2 emission and its relationship to soil properties under different tillage systems

There is a lack of understanding as to which soil property is the most important at regulating the temporal variability of soil CO2 emissions on China's Loess Plateau. The objective of this study was to evaluate the CO2 emissions and their relationships to certain soil properties in a winter wheat (Triticum aestivum L.) field subject to no-till (NT) and conventional tillage (CT) practices. The CO2 emissions were significantly higher in the CT (257.6mg CO(2)m(-2) h(-1)), compared with the NT (143.8mg CO(2)m(-2) h(-1)), treatment. Soil organic matter content and carbon stock were 8% and 14% higher, respectively, in the NT, compared with the CT, treatment. Regression analyses between the CO2 emissions and soil properties, including soil temperature and carbon stock, explained up to 88% and 60% of the temporal variability in CO2 emissions in the NT and CT treatments, respectively. Linear correlations between the soil temperature and CO2 emissions were recorded in both the NT and CT treatments. Soil temperature was the most important factor in terms of understanding the temporal variability in CO2 emissions in wheat fields of the study area.