Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Biogeosciences, 8, 2377-2390, 2011
https://doi.org/10.5194/bg-8-2377-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
30 Aug 2011
Modeling impacts of farming management practices on greenhouse gas emissions in the oasis region of China
Y. Wang1, G. J. Sun1, F. Zhang1, J. Qi1,2, and C. Y. Zhao1 1Key Laboratory of Arid and Grassland Agro-Ecology (MOE), Lanzhou University, Lanzhou, Gansu, 730000, China
2Center for Global Change and Earth Observations, Michigan State University, East Lansing, MI, 48823, USA
Abstract. Agricultural ecosystems are major sources of greenhouse gas (GHG) emissions, specifically nitrous oxide (N2O) and carbon dioxide (CO2). An important method of investigating GHG emissions in agricultural ecosystems is model simulation. Field measurements quantifying N2O and CO2 fluxes were taken in a summer maize ecosystem in Zhangye City, Gansu Province, in northwestern China in 2010. Observed N2O and CO2 fluxes were used for validating flux predictions by a DeNitrification-DeComposition (DNDC) model. Then sensitivity tests on the validated DNDC model were carried out on three variables: climatic factors, soil properties and agricultural management. Results indicated that: (1) the factors that N2O emissions were sensitive to included nitrogen fertilizer application rate, manure amendment and residue return rate; (2) CO2 emission increased with increasing manure amendment, residue return rate and initial soil organic carbon (SOC); and (3) net global warming potential (GWP) increased with increasing N fertilizer application rate and decreased with manure amendment, residue return rate and precipitation increase. Simulation of the long-term impact on SOC, N2O and net GWP emissions over 100 yr of management led to the conclusion that increasing residue return rate is a more efficient method of mitigating GHG emission than increasing fertilizer N application rate in the study area.

Citation: Wang, Y., Sun, G. J., Zhang, F., Qi, J., and Zhao, C. Y.: Modeling impacts of farming management practices on greenhouse gas emissions in the oasis region of China, Biogeosciences, 8, 2377-2390, https://doi.org/10.5194/bg-8-2377-2011, 2011.
Publications Copernicus
Download
Share