title: [Effects of nitrogen fertilization, soil moisture and soil temperature on soil respiration during summer fallow season].
abstract: On the loess plateau, summer fallow season is a hot rainy time with intensive soil microbe activities. To evaluate the response of soil respiration to soil moisture, temperature, and N fertilization during this period is helpful for a deep understanding about the temporal and spatial variability of soil respiration and its impact factors, then a field experiment was conducted in the Changwu State Key Agro-Ecological Experimental Station, Shaanxi, China. The experiment included five N application rates: unfertilized 0 (N0), 45 (N45), 90 (N90), 135(N135), and 180 (N180) kg x hm(-2). The results showed that at the fallow stage, soil respiration rate significantly enhanced from 1.24 to 1.91 micromol x (m2 x s)(-1) and the average of soil respiration during this period [6.20 g x (m2 x d)(-1)] was close to the growing season [6.95 g x (m2 x d)(-1)]. The bivariate model of soil respiration with soil water and soil temperature was better than the single-variable model, but not so well as the three-factor model when explaining the actual changes of soil respiration. Nitrogen fertilization alone accounted for 8% of the variation soil respiration. Unlike the single-variable model, the results could provide crucial information for further research of multiple factors on soil respiration and its simulation.
authors.affiliation: College of Resources and Environment, Northwest A & F University, Yangling 712100, China. xiaoyufeifei2008@163.com
authors.forename: Fang
authors.initials: F
authors.lastname: Zhang
authors.forename: Sheng-Li
authors.initials: SL
authors.lastname: Guo
authors.forename: Jun-Liang
authors.initials: JL
authors.lastname: Zou
authors.forename: Ze
authors.initials: Z
authors.lastname: Li
authors.forename: Yan-Jun
authors.initials: YJ
authors.lastname: Zhang
mesh_terms: D000531:Altitude; D002244:Carbon / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis; D002681:China; D005306:Fertilization; D009584:Nitrogen / Q000494:pharmacology*; D009930:Organic Chemicals / Q000032:analysis; D012621:Seasons; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D013696:Temperature; D014867:Water / Q000032:analysis
chemical_list: D009930:Organic Chemicals; D012987:Soil; D014867:Water; D002245:Carbon Dioxide; D002244:Carbon; D009584:Nitrogen