IRRIGATION SCIENCE, cilt.44, sa.3, 2026 (SCI-Expanded, Scopus)
Irrigation and fertilization are standard practices in vegetable cultivation to enhance crop productivity. While manure application improves crop yield and soil health, assessing its potential impact on CO2 emissions, driven by increased soil organic carbon across varying irrigation levels, is essential for environmental sustainability. This research is motivated by limited understanding of how fluctuating irrigation levels influence CO2 emission dynamics in cabbage fields treated with cattle manure. Consequently, this study aimed to assess soil CO2 emissions under different irrigation levels in soil amended with cattle manure. A two-year field experiment was conducted using three fertilization treatments, mineral fertilization (M) as a control, medium-high soil organic matter content of 3% (CM1), and high soil organic matter content of 4.5% (CM2), integrated with three irrigation levels: W1 (100%), W2 (75% of W1), and W3 (50% of W1), with three replicates per treatment. The results indicated that manure application significantly increased seasonal CO2 emissions when combined with full irrigation (W1). Compared to mineral fertilization, total CO2 emissions in the CM1 and CM2 treatments increased by 135.5% and 158.6%, respectively. However, due to higher crop productivity, CO2 emissions per unit yield increased by only 50.7% and 50.4%. Furthermore, emissions per unit of water consumption rose by 140.1% and 164.7%, respectively. Statistical analysis revealed that emissions were positively correlated with soil moisture and negatively correlated with soil temperature. While the W3 treatment reduced total CO2 emissions by 27.9% compared to W1, it resulted in a 44.2% increase in emissions per unit yield and an 11.0% decrease in emissions per unit of water consumption. Based on fertilizer performance and yield efficiency, applying cattle manure in conjunction with the W1 and W2 treatments is recommended, as these regimes produce higher total yields and lower CO2 emissions per unit yield than the W3 treatment. Conversely, in water-scarce regions, the W3 treatment may be a more practical strategy for minimizing emissions per unit of water consumed.