The impact of rainfall on soil respiration in a rain-fed maize cropland

Abstract

The research on the impact of rainfall on soil respiration is significant to predict accurately the carbon balance of terrestrial ecosystems under future climate change. It is consensus that a certain degree of drought would suppress soil respiration, as well as the processes of water, carbon and nitrogen would be excited after re鄄watering by precipitation or irrigation. However, some research showed the suppression of soil respiration by precipitation. As a disturbance factor, the effect of precipitation on soil respiration is complex because of different vegetation and soil type in different regions. It is necessary to reveal the impact of rainfall amount, intensity and duration on soil respiration under different soil water content, as well to make clear the turning point of suppression or excitation of soil respiration in different regions. In a maize cropland located at eastern Loess Plateau, soil respiration and its components was measured continuously around 3 rainfall incidents based on in situ observation technique, and the impact of rainfall on soil respiration and its components was analyzed. The study was conducted in Shouyang county, Shanxi Province. It is a semi鄄humid area. The seasonal variation of precipitation is large, about 70% of annual amount occurs from June to September. In the field of maize cropland, soil respiration and its components were measured continuously by LI鄄8150 Soil CO 2 Flux System. Soil respiration was divided into microbial respiration and root respiration respectively based on root exclude method. Each treatment was repeated

Precipitation alters plastic film mulching impacts on soil respiration in an arid area of northwest China

“…The obtained Q 10 values of 1.25-1.65 (Table 2, except for in the planting hole) are below the median of 2.4 reported in a literature review of global soil respiration (Raich and Schlesinger, 1992). Additionally, they are much smaller than the Q 10 of 3.8 found in rain-fed maize cropland on the Loess Plateau of China (Xiang et al, 2012). In contrast, relatively higher correlations between R s and SWC indicate that the SWC may be the main factor affecting R s in a PFM field under drip irrigation.…”