Nitrogen management and supplemental irrigation affected greenhouse gas emissions, yield and nutritional quality of fodder maize in an arid region
2022
Ahmad, Irshad | Yan, Zhengang | Kāmrān, Muḥammad | Ikram, Khushnuma | G̲h̲anī, Muḥammad ʻUs̲mān | Hou, Fujiang
Deficit and erratic precipitation in arid regions and imbalance nitrogen (N) fertilization can result in lower yield and nutritional quality of fodder maize. The objectives of the experiment were to investigate the effect of N (urea 46% N) rates i.e., 225 (N₁), 300 (N₂) and 375 kg N ha–¹ (N₃) under 600 (W₁) and 900 mm ha–¹ (W₂) supplemental irrigation levels on the greenhouse gas (GHG) emissions, yield and nutritional quality of fodder maize. The treatments combination comprised of N₁W₁, N₂W₁, N₃W₁, N₁W₂, N₂W₂ and N₃W₂. N fertilization and supplemental irrigation levels significantly affected soil moisture content (SMC) and soil temperature (ST), whereas maximum SMC and minimum ST were recorded in N₃W₂. Increasing N rate decreased soil ammonium nitrogen content (NH₄⁺-N) and increased nitrate nitrogen content (NO₃–-N) and maximum NH₄⁺-N was recorded in N₁W₁ and maximum NO₃–-N in N₃W₁. Methane (CH₄) uptake was higher in W₁ compared with the W₂, and maximum CH₄ uptake was recorded in N₃W₁ followed by N₃W₂. Nitrous oxide (N₂O) and carbon dioxide (CO₂) emissions were higher in W₁ compared with the W₂, and maximum N₂O and CO₂ emissions were recorded in N₃W₁. Cumulative emission of N₂O and CO₂, CH₄ uptake, global warming potential (GWP), and greenhouse gas intensity (GHGI) were higher in W₁ compared with W₂ and their maximum values were recorded in N₃W₁. Treatment N₃W₂ significantly improved the forage yield and nutritional quality of fodder maize by improving the crude protein content and ether extract content, while reducing neutral detergent and acid detergent fibers contents. In conclusion, treatment N₃W₂ improved SMC, forage yield, grain yield, and nutritional quality of fodder maize as well as reduced GHG emissions, GWP and GHGI in an arid region.
显示更多 [+] 显示较少 [-]