title: Temperature Sensitivity of Soil Respiration to Nitrogen Fertilization: Varying Effects between Growing and Non-Growing Seasons.
abstract: Nitrogen (N) fertilization has a considerable effect on food production and carbon cycling in agro-ecosystems. However, the impacts of N fertilization rates on the temperature sensitivity of soil respiration (Q10) were controversial. Five N rates (N0, N45, N90, N135, and N180) were applied to a continuous winter wheat (Triticum aestivum L.) crop on the semi-arid Loess Plateau, and the in situ soil respiration was monitored during five consecutive years from 2008 to 2013. During the growing season, the mean soil respiration rates increased with increasing N fertilization rates, peaking at 1.53 μmol m-2s-1 in the N135 treatment. A similar dynamic pattern was observed during the non-growing season, yet on average with 7.3% greater soil respiration rates than the growing season. In general for all the N fertilization treatments, the mean Q10 value during the non-growing season was significantly greater than that during the growing season. As N fertilization rates increased, the Q10 values did not change significantly in the growing season but significantly decreased in the non-growing season. Overall, N fertilization markedly influenced soil respirations and Q10 values, in particular posing distinct effects on the Q10 values between the growing and non-growing seasons.
authors.affiliation: College of Resources and Environment, Northwest A&F University, Yangling, China.
authors.forename: Qingfang
authors.initials: Q
authors.lastname: Liu
authors.affiliation: College of Resources and Environment, Northwest A&F University, Yangling, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.affiliation: State key laboratory of soil erosion and dryland farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Rujian
authors.initials: R
authors.lastname: Li
authors.affiliation: State key laboratory of soil erosion and dryland farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi, China.|Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resource, Yangling, China.
authors.forename: Yaxian
authors.initials: Y
authors.lastname: Hu
authors.affiliation: College of Resources and Environment, Northwest A&F University, Yangling, China.|State key laboratory of soil erosion and dryland farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi, China.|Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resource, Yangling, China.
authors.forename: Shengli
authors.initials: S
authors.lastname: Guo
mesh_terms: D018533:Biomass; D017753:Ecosystem; D004784:Environmental Monitoring; D005308:Fertilizers / Q000032:analysis*; D009584:Nitrogen / Q000032:analysis*; D012621:Seasons; D012987:Soil / Q000737:chemistry*; D013696:Temperature; D014908:Triticum / Q000254:growth & development*
chemical_list: D005308:Fertilizers; D012987:Soil; D009584:Nitrogen