Responses of soil respiration to warming vary between growing season and non-growing season in a mountain forest of southwestern China

摘要

Understanding the temperature sensitivity of soil respiration is very important to quantify the climate–carbon cycle feedback. Most existing studies have only focused on responses of growing-season respiration to warming. Soil respiration of non-growing season may be more sensitive to warming. However, to our knowledge, this hypothesis remains poorly understood. An experiment was conducted in a mountain pine forest of southwestern China to compare the sensitivity of soil respiration to warming (+5 °C) between growing and non-growing seasons. Experimental warming decreased soil moisture but increased soil respiration on most of the measuring dates. Warming-caused increase in soil respiration and Q10 value was greater during the growing season than during the non-growing season. Q10 values decreased linearly with warming-induced changes in soil moisture. This study provides preliminary evidence that soil respiration of non-growing season is less sensitive to warming compared with that of growing season in the mountain forests experiencing monsoon climate