Estimation of nitrous oxide emission from Hungarian semi-arid sandy and loess grasslands; effect of soil parameters, grazing, irrigation and use of fertilizer

Diurnal pattern of nitrous oxide emissions from soils under different vertical moisture distribution conditions

“…For the SW treatment, peaks appeared at 16:00 and 18:00 h on 17 June and 1 July, and at 14:00 h on 22 July (Figures 1d, 1e, and 1f). Mean flux on 1 July (1110.1 μg N2O m -2 h -1 ) was much lower than on 17 June (2741.0 μg N2O m -2 h -1 ), which might be attributable to the low soil moisture content on 1 July that inhibited the nitrifying activity Horváth et al, 2010;Tian et al, 2012). For the SUW treatments, N 2O fluxes followed a diurnal pattern similar to the SW treatment with peak fluxes of 2242.6, 3261.0, and 2678.1 μg N2O m -2 h -1 for the SUW12, SUW15, and SUW18 treatments, respectively, on 17 June (Figure 1d).…”

Increased Nitrous Oxide Emissions Resulting from Nitrogen Addition and Increased Precipitation in an Alpine Meadow Ecosystem

“…Glaciers melted and shrank by 7% (about 3.79×10 3 km 2 ) during the period 1960-2005, and precipitation gradually increased during peak growing seasons, with a notable 14% increase in precipitation per decade in Tibet [3]. Under longterm medium soil moisture conditions, N 2 O is dominant, with N 2 mostly emitted from saturated soil [1]. Aerobic , Guangmin Cao 2 ,Yikang Li nitrification and anaerobic denitrification are responsible for soil N 2 O production [1,4].…”

“…Under longterm medium soil moisture conditions, N 2 O is dominant, with N 2 mostly emitted from saturated soil [1]. Aerobic , Guangmin Cao 2 ,Yikang Li nitrification and anaerobic denitrification are responsible for soil N 2 O production [1,4]. Nitrogen deposition had been shown to increase N 2 O emissions; the relationship between the two variables was not found to be significant on alpine meadows but had been shown to be significant in alpine grasslands during the growing season [5,6].…”

“…An increase in the quantity of reactive nitrogen in the atmosphere, together with increased precipitation, alters soil chemistry and the physiology of soil microbes, and influences the balance of the greenhouse gas N 2 O [1,2].…”

“…Average N 2 O flux had increased by 25.56% following the application of 10 g N m 2 y -1 in semi-arid grassland [7]. Irrigation was found to have only a small effect on yearly emissions during normal years, but had enhanced emissions by 70% during dry years [1]. Rainfall-stimulated N 2 O emissions on corn farmland and increased precipitation could exert a greater influence on N 2 O emissions in grassland soils [1,6,7].…”