[Emission of NH and NO from Spinach Field Treated with Different Fertilizers].

Agricultural management techniques such as fertilizer or manure application have substantial influence on NH and NO emissions and, by understanding this influence, management strategies can be developed to reduce them. An experiment was conducted in a greenhouse at Hunan Agricultural University during 2012 to 2013, to investigate effects of different fertilizers on NH and NO emissions. The treatments included control without fertilizer (CK), swine composting fertilizer (SC), stored swine manure fertilizer (SS), and chemical fertilizer (FC). The fluxes of NH and NO were collected by venting method and static-chamber method, respectively. The results showed that during the spinach growth season, compared with FC, loss of both NH and NO for SC were reduced by 52.9% and 95.12%, respectively(<0.01). However, loss of NH for SS increased by 24.8%, and loss of NO reduced by 48.8% compared with FC. Loss rate of NH were SS (10.97%) > FC (4.19%) > SC(2.74%), and emission coefficient for NO were FC(4.50%) > SC(2.21%) > SS(0.60%). Yield and utilization of nitrogen for SC were reduced by 19.61% and 13.20% compared with FC, respectively, but not significantly; and significantly reduced by 27.9% and 40.0% compared with SS, respectively. Loss of gases (NH and NO) for SC were 1.83%, which was the lowest, while utilization of nitrogen for SC was 13.20%, similar with FC. Greenhouse temperature was not the critical factor during the spinach planting in winter, but soil water was. Therefore, optimizing manure management could reduce ammonia volatilization and NO emission loss without decreasing vegetables production, and the present data indicated that SC would be optimal for better yields with reduced ammonia volatilization and NO emission loss.