Title: Nitrogen management and supplemental irrigation affected greenhouse gas emissions, yield and nutritional quality of fodder maize in an arid region
Authors: Irshad Ahmad, Zhengang Yan, Muhammad Kamran, Khushnuma Ikram, Muhammad Usman Ghani, Fujiang Hou*
Journal: Agricultural Water Management
Impact factor: IF2021 = 4.516
Abstract: 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.