Effects of experimental warming and nitrogen addition on soil respiration and CH4 fluxes from crop rotations of winter wheat-soybean/fallow

摘要

Soil respiration and CH4 emissions play a significant role in the global carbon balance. However, in situ studies in agricultural soils on responses of soil respiration and CH4 fluxes to climate warming are still sparse, especially from long-term studies with year-round heating. A warming experiment was conducted at Luancheng research station in the North China Plain from 2008 to 2013. Two levels of temperature (T: increase on average 1.5 degrees C at 5 cm soil depth by infrared heaters, C: ambient temperature) were combined with two levels of nitrogen (N) treatments (N1: with 315 kg N ha(-1) y(-1), NO: no nitrogen input) in the farmland.