Soil respiration in a pea field on the Loess Plateau was studied in 2007. The researchers found that soil respiration varied throughout the day, with higher rates in summer than in winter. The soil in the area absorbs CO2 in winter, leading to an underestimation of respiration rates. Soil temperature was the main factor influencing respiration, while moisture had little effect. These findings provide important information for understanding carbon cycling in farmland ecosystems.