Effect of nitrogen fertilization on methane flux in a structured clay soil cultivated with onion in Central Hokkaido, Japan

Greenhouse gas fluxes respond to different N fertilizer types due to altered plant-soil-microbe interactions

“…This was unexpected, as previous studies showed that CH 4 oxidation is potentially inhibited by NH 4 + (e.g., Steudler et al 1989;Mosier et al 1991;Hütsch 2001;Hu et al 2002) or NO 3 − (Kightley et al 1995;Wang and Ineson 2003;Reay and Nedwell 2004). Still, our results are supported by several other studies that found a lack of inhibition or even stimulation of CH 4 oxidation following N addition (e.g., Bodelier et al 2000;Hilger et al 2000;Sitaula et al 2000;De Visscher and Van Cleemput 2003).…”

“…Aerated soils act as sinks of CH 4 , and their sink strength has been estimated to be 3%-9% of the global annual removal of CH 4 from the atmosphere (Smith et al 2000). Application of mineral N fertilizers has been shown to reduce the natural CH 4 oxidation capacity of agricultural soils and may therefore lead to increased CH 4 emissions (e.g., Hütsch 2001;Hu et al 2002). This increase has mainly been attributed to the competitive inhibition of the enzyme methane monooxygenase, and to the resulting decrease in pH when NH 4 + is applied to soil (Bedard and Knowles 1989;Hütsch 1998).…”

Dissolved N2O, CH4, and CO2emissions from subsurface-drainage in a structured clay soil cultivated with onion in Central Hokkaido, Japan

“…The measurements were conducted 2-5 times a month from April to October, and once a month in November and January. The methods for the measurements and calculations were described by Kusa et al (2002) and Hu et al (2002). Kusa et al (2002) and Hu et al (2002) reported the direct emissions of N 2 0 and CH 4 from this field, respectively.…”

N2O and CH4fluxes from a volcanic grassland soil in Nasu, Japan: Comparison between manure plus fertilizer plot and fertilizer-only plot

“…It is important to note that the CH 4 flux observed from the soil surface is defined as the net positive flux from soil to the atmosphere. Nitrogen fertilizer has reduced CH 4 consumption in the soil (Hu et al . 2002; Jensen and Olsen 1998; Mosier et al .…”

“…It is important to note that the CH 4 flux observed from the soil surface is defined as the net positive flux from soil to the atmosphere. Nitrogen fertilizer has reduced CH 4 consumption in the soil (Hu et al 2002;Jensen and Olsen 1998;Mosier et al 1991); however, manure has not altered CH 4 consumption in the soil (Hütsch et al 1993). Important environmental factors that control CH 4 oxidation are fertilization, soil moisture, soil temperature and soil pH (Amaral et al 1998;Castro et al 1995;Dunfield et al 1993;Mori et al 2005;Whalen and Reeburgh 1996).…”