HR: 1330h
AN: B32B-0380    [PDF]
TI: N2O, NO, CO2 and CH4 emissions from Chinese cabbage residues addition in a Japanese Andosol as affected by different soil moisture
AU: * Cheng, W
EM: cheng@niaes.affrc.go.jp
AF: National Institute for Agro-Environmental Sciences, 3-1-3, Kannondai, Tsukuba, Iba 305-8604 Japan
AU: Tsuruta, H
EM: htsuruta@xd6.so-net.ne.jp
AF: National Institute for Agro-Environmental Sciences, 3-1-3, Kannondai, Tsukuba, Iba 305-8604 Japan
AU: Yagi, K
EM: kyagi@affrc.go.jp
AF: National Institute for Agro-Environmental Sciences, 3-1-3, Kannondai, Tsukuba, Iba 305-8604 Japan
AB: It is considered that incorporated crop residues to soil not only affect soil fertility, but also contribute greenhouse gases (N2O, CO2 and CH4) emissions. A laboratory incubation experiment was conducted to examine the effects of Chinese cabbage residues addition and soil moisture on N2O, NO, CO2 and CH4 emissions form Japanese Andosol. Six treatments were designed by residue factors in 2 levels (with and without residue addition) and soil moisture factors in 3 levels (40, 60, and 80% of water filled pore space (WFPS)). Amount of added residues was 0.543% (w/w) of dry soil, equivalent to 200 mg N/kg soil addition. Gas sampling for N2O, NO, CO2 and CH4 fluxes was carried out two or three times a week, and soil sampling for soluble C, NH4, NO3 and extractable organic N measurements was taken up every week during 85 days incubation at 25oC. The results showed that amounts of residue-derived N2O emitted from 40, 60 and 80% WFPS soil moisture conditions were 0.014, 0.019 and 2.86%, respectively, of residue addition N. Residue-derived N2O emitted from 80% WFPS soil moisture condition was 204 and 151 times higher than that from 40 and 60%. NO emissions were only detected in early period of incubation at all treatments. The amounts of residue-derived NO emitted from 40, 60 and 80% WFPS were 0.13, 0.06 and 0.04%, respectively, of residue addition N. The amounts of residues-derived CO2-C were accounted for 29.36, 33.91 and 44.79%, respectively, of the residue addition C from 40, 60, and 80% WFPS soil moisture conditions. CH4 fluxes results indicated that CH4 oxidation was found in all treatments. Calculated global warming potential (GWP) from CO2, CH4 and N2O emission rates during 85days incubation showed that GWP were 3.02 and 2.62 times higher in 80% WFPS soil moisture condition than that in 40 and 60%, because a large amount of residue-derived N2O emitted from 80% WFPS moisture condition.
DE: 0315 Biosphere/atmosphere interactions
DE: 0400 Biogeosciences
DE: 1615 Biogeochemical processes (4805)
DE: 4820 Gases
SC: Biogeosciences [B]
MN: 2003 Fall Meeting