Limits...
Methane, carbon dioxide and nitrous oxide fluxes in soil profile under a winter wheat-summer maize rotation in the North China Plain.

Wang Y, Hu C, Ming H, Oenema O, Schaefer DA, Dong W, Zhang Y, Li X - PLoS ONE (2014)

Bottom Line: GHG production and consumption in soil layers were inferred using Fick's law.Results showed nitrogen application significantly increased N2O fluxes in soil down to 90 cm but did not affect CH4 and CO2 fluxes.The top 0-60 cm of soil was a sink of atmospheric CH4, and a source of both CO2 and N2O, more than 90% of the annual cumulative GHG fluxes originated at depths shallower than 90 cm; the subsoil (>90 cm) was not a major source or sink of GHG, rather it acted as a 'reservoir'.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei, China.

ABSTRACT
The production and consumption of the greenhouse gases (GHGs) methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O) in soil profile are poorly understood. This work sought to quantify the GHG production and consumption at seven depths (0-30, 30-60, 60-90, 90-150, 150-200, 200-250 and 250-300 cm) in a long-term field experiment with a winter wheat-summer maize rotation system, and four N application rates (0; 200; 400 and 600 kg N ha(-1) year(-1)) in the North China Plain. The gas samples were taken twice a week and analyzed by gas chromatography. GHG production and consumption in soil layers were inferred using Fick's law. Results showed nitrogen application significantly increased N2O fluxes in soil down to 90 cm but did not affect CH4 and CO2 fluxes. Soil moisture played an important role in soil profile GHG fluxes; both CH4 consumption and CO2 fluxes in and from soil tended to decrease with increasing soil water filled pore space (WFPS). The top 0-60 cm of soil was a sink of atmospheric CH4, and a source of both CO2 and N2O, more than 90% of the annual cumulative GHG fluxes originated at depths shallower than 90 cm; the subsoil (>90 cm) was not a major source or sink of GHG, rather it acted as a 'reservoir'. This study provides quantitative evidence for the production and consumption of CH4, CO2 and N2O in the soil profile.

Show MeSH

Related in: MedlinePlus

CH4, CO2 and N2O concentrations (mean ± standard deviations, n = 3) in soil air at various soil depths in a winter wheat–summer maize double cropping rotation receiving 0, 200, 400 and 600 kg of N ha−1 year−1, in 2007–2008 (A); NO3-N contents (mean ± standard deviations, n = 3) at various soil depths as function of N fertilizer application rate, in 2007–2008 (B); Profiles of concentration and annual cumulative flux of CH4, CO2 and N2O, in 2007–2008 (mean ± standard deviations, n = 4).Same letters next to the bars indicated no significant differences between slope positions (P<0.05). (C). Note the differences in X-axes.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4043841&req=5

pone-0098445-g001: CH4, CO2 and N2O concentrations (mean ± standard deviations, n = 3) in soil air at various soil depths in a winter wheat–summer maize double cropping rotation receiving 0, 200, 400 and 600 kg of N ha−1 year−1, in 2007–2008 (A); NO3-N contents (mean ± standard deviations, n = 3) at various soil depths as function of N fertilizer application rate, in 2007–2008 (B); Profiles of concentration and annual cumulative flux of CH4, CO2 and N2O, in 2007–2008 (mean ± standard deviations, n = 4).Same letters next to the bars indicated no significant differences between slope positions (P<0.05). (C). Note the differences in X-axes.

Mentions: Mean concentrations and its standard deviations of CH4, CO2 and N2O at each depth are shown in Figure 1 A, as function of N application rates. Mean CH4 concentration decreased with soil depth. Ambient air CH4 concentration in the area was about 2.2 ppmv. At a depth of 30 cm, CH4 concentration ranged between 1.4 and 1.6 ppmv and at depth of 60 to 300 cm between 0.3 and 0.6 ppmv. There were no clear effects of N fertilizer application on the mean CH4 concentration (Figure 1 A). Mean CH4 concentrations decreased significantly at soil depths of 0, 30, 60 and 90 cm (P<0.05); changes in mean concentration below a depth of 90 cm were not significant (Figure 1 C).


Methane, carbon dioxide and nitrous oxide fluxes in soil profile under a winter wheat-summer maize rotation in the North China Plain.

Wang Y, Hu C, Ming H, Oenema O, Schaefer DA, Dong W, Zhang Y, Li X - PLoS ONE (2014)

CH4, CO2 and N2O concentrations (mean ± standard deviations, n = 3) in soil air at various soil depths in a winter wheat–summer maize double cropping rotation receiving 0, 200, 400 and 600 kg of N ha−1 year−1, in 2007–2008 (A); NO3-N contents (mean ± standard deviations, n = 3) at various soil depths as function of N fertilizer application rate, in 2007–2008 (B); Profiles of concentration and annual cumulative flux of CH4, CO2 and N2O, in 2007–2008 (mean ± standard deviations, n = 4).Same letters next to the bars indicated no significant differences between slope positions (P<0.05). (C). Note the differences in X-axes.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4043841&req=5

pone-0098445-g001: CH4, CO2 and N2O concentrations (mean ± standard deviations, n = 3) in soil air at various soil depths in a winter wheat–summer maize double cropping rotation receiving 0, 200, 400 and 600 kg of N ha−1 year−1, in 2007–2008 (A); NO3-N contents (mean ± standard deviations, n = 3) at various soil depths as function of N fertilizer application rate, in 2007–2008 (B); Profiles of concentration and annual cumulative flux of CH4, CO2 and N2O, in 2007–2008 (mean ± standard deviations, n = 4).Same letters next to the bars indicated no significant differences between slope positions (P<0.05). (C). Note the differences in X-axes.
Mentions: Mean concentrations and its standard deviations of CH4, CO2 and N2O at each depth are shown in Figure 1 A, as function of N application rates. Mean CH4 concentration decreased with soil depth. Ambient air CH4 concentration in the area was about 2.2 ppmv. At a depth of 30 cm, CH4 concentration ranged between 1.4 and 1.6 ppmv and at depth of 60 to 300 cm between 0.3 and 0.6 ppmv. There were no clear effects of N fertilizer application on the mean CH4 concentration (Figure 1 A). Mean CH4 concentrations decreased significantly at soil depths of 0, 30, 60 and 90 cm (P<0.05); changes in mean concentration below a depth of 90 cm were not significant (Figure 1 C).

Bottom Line: GHG production and consumption in soil layers were inferred using Fick's law.Results showed nitrogen application significantly increased N2O fluxes in soil down to 90 cm but did not affect CH4 and CO2 fluxes.The top 0-60 cm of soil was a sink of atmospheric CH4, and a source of both CO2 and N2O, more than 90% of the annual cumulative GHG fluxes originated at depths shallower than 90 cm; the subsoil (>90 cm) was not a major source or sink of GHG, rather it acted as a 'reservoir'.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei, China.

ABSTRACT
The production and consumption of the greenhouse gases (GHGs) methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O) in soil profile are poorly understood. This work sought to quantify the GHG production and consumption at seven depths (0-30, 30-60, 60-90, 90-150, 150-200, 200-250 and 250-300 cm) in a long-term field experiment with a winter wheat-summer maize rotation system, and four N application rates (0; 200; 400 and 600 kg N ha(-1) year(-1)) in the North China Plain. The gas samples were taken twice a week and analyzed by gas chromatography. GHG production and consumption in soil layers were inferred using Fick's law. Results showed nitrogen application significantly increased N2O fluxes in soil down to 90 cm but did not affect CH4 and CO2 fluxes. Soil moisture played an important role in soil profile GHG fluxes; both CH4 consumption and CO2 fluxes in and from soil tended to decrease with increasing soil water filled pore space (WFPS). The top 0-60 cm of soil was a sink of atmospheric CH4, and a source of both CO2 and N2O, more than 90% of the annual cumulative GHG fluxes originated at depths shallower than 90 cm; the subsoil (>90 cm) was not a major source or sink of GHG, rather it acted as a 'reservoir'. This study provides quantitative evidence for the production and consumption of CH4, CO2 and N2O in the soil profile.

Show MeSH
Related in: MedlinePlus