Short Term Effects of Preceding Crops and Tillage Methods on Soil CO2 Fluxes in the Cropland of the North China Plain

The influence of tillage method and crop rotation on soil respiration (SR) has been widely studied. However, very few studies have investigated the combined effects of different preceding crop types and tillage methods on SR rates of the same crop in the following season. In this study, two tillage methods including no-till (NT) and conventional tillage (CT) and three preceding crops (maize, peanut and soybean) were selected to study their combined effects on SR. The results showed that (1) for the same preceding crop, the total amount of soil respiration (TSR) of NT treatment was significantly higher than that of CT treatment; (2) under the same tillage method, preceding maize treatment generally had higher SR rates than other preceding crop treatments; (3) the temperature sensitivity (Q(10)) values of preceding soybean crops were significantly lower than that of preceding maize and peanut crops under CT treatment, but the values of preceding soybean crops were higher than that of preceding maize and peanut crops under CT treatment, and the difference between preceding soybean and peanut crop was significant. Overall, the results indicated that NT method and preceding maize potentially increased SR by changing soil temperature and soil water content in our study area, further studies should strengthen to reveal the microbiological mechanism under different tillage methods and preceding crops.