Effects of intercropping on soil CO2 and N2O emissions from upland: A review.

Abstract

Greenhouse gases (GHGs) emission from arable field is a hot topic recently, adopting appropriate cropping systems is an effective way to reduce GHGs emission. This paper reviewed the impacts and mechanisms of intercropping on soil CO2 and N2O emissions in upland field. Rational intercropping systems could increase soil organic carbon (SOC), promote the transformation of straw to SOC, slow down mineralization rate of SOC, and hence reduce soil CO2 emissions. The Poaceae intercropping with legume could maintain the stability of yield while reducing synthetic N inputs, formation of inorganic N by residue decomposition and soil mineral N, and further reducing soil N2O emission. In addition, crop interactions in intercropping system and filed microclimate were important factors on GHGs emission as well. It is necessary to extent the period of researches in field GHGs emission in order to fully understand the underlying mechanisms of GHGs emission in farm land, especially the function of soil microorganisms at molecular level. It would provide theoretical knowledge in building environment-friendly agricultural system in the future.