A systematic review on the impact of cropping systems on carbon dioxide emissions in semi-arid regions

Semi-arid regions are predominantly vulnerable to climate fluctuations and change, which can contribute to higher CO2 emissions. Therefore, there is a need for sustainable farming practices that mitigate climate change as the demand for food and feed production increases. This study systematically reviewed existing literature on the impact of conservation agriculture on carbon dioxide fluxes in semi-arid regions. Subsequently, a systematic search which adhered Preferred Reporting Items for Systematic Review on two search engines (i.e., Scopus and Web of Science) produced 1312 articles, whereof 31 relevant studies met the inclusion criteria of this paper. The results highlighted that conservation agriculture increases soil organic carbon in semi-arid regions, which further reduce the emission of carbon dioxide. Several studies reported that incorporating legumes into crop rotation systems enhanced carbon sequestration, and subsequently reduced the emission of carbon. Moreover, it has been noted that the type of crop rotation, residue management and tillage practice used in a particular system could influence the reduction of carbon dioxide emissions. However, it was recommended that there is a need for long-term studies on the impact of conservation agriculture in order to understand its positive impact in carbon dioxide fluxes and climate change mitigation. Further research is needed on the long term impact of conservation agriculture on carbon dioxide emissions.