Regulating soil microclimate and greenhouse gas emissions with rye mulch in cabbage cultivation

Agriculture is a major contributor to greenhouse gas (GHG) emissions and one of the sectors most vulnerable to climate change. Mulching, the application of an organic layer to an agricultural field, is one promising agricultural practice, with the aim of reducing evaporation, preventing soil erosion and stabilising yields. While mulching has become a popular research topic in recent years, little is known about its effects on climate change adaptation and GHG emissions. We conducted weekly measurements of nitrous oxide (N2O) emissions and analyzed related soil parameters, including soil nitrate content, temperature, and moisture, in an organic cabbage field with mulching and fertilization as treatments. Fertilization increased N2O emissions, but rye mulch had no significant effect on emissions. Soil microclimatic parameters changed substantially under mulch, with significantly higher soil moisture and lower, less fluctuating soil temperatures. At the same time, yields increased with fertilization and mulching combined. In conclusion, our findings suggest that rye mulching can aid in climate change adaptation via soil microclimatic buffering, while not increasing GHG emissions and without compromising cabbage yield, owing to the high C/N ratio of the rye mulch.