title: [Impact of microbial aggregating agents on soil aggregate stability under addition of exogenous nutrients].
abstract: In this study, we investigated the effects of biological aggregating agents (fungal hyphae and microbial extracellular polysaccharides) soil aggregate (with different sizes) stability under addition of exogenous nutrients. The exogenous nutrients included glucose and ammonium nitrate. Experiments were conducted in a 30 d incubation period with three treatments: (1) the control (0.5 mg x g(-1) soil); (2) CN5 (0.5 mg x g(-1) soil, 0.1 mg x g(-1) soil, C/N = 5); (3) CN10 (0.5 mg x g(-1) soil, 0.05 mg x g(-1) soil, C/N = 10). Results showed that soil respiration rates were not significantly different among the three treatments, with maximums being about 3.10 mg x (h x kg)(-1), indicating that the impact of inorganic nitrogen fertilizer was not obvious in a short term. Aside from 5 d, macroaggregates amount of CK (15.67%) was observably lower than those of CN5 (25.32%) and CN10 (24.63%), there were no remarkable discrepancies among 3 treatments in other incubation period. The insignificant difference in the aggregate amounts among the three treatments suggested that the influence of glucose on microbial activities surpassed the inorganic nitrogen fertilizer in shortterm in the study.
authors.affiliation: School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China. moyanhua811@gmail.com
authors.forename: Yan-Hua
authors.initials: YH
authors.lastname: Mo
authors.forename: Jia
authors.initials: J
authors.lastname: Tang
authors.forename: Ren-Duo
authors.initials: RD
authors.lastname: Zhang
authors.forename: Fang-Zhou
authors.initials: FZ
authors.lastname: Li
mesh_terms: D001419:Bacteria / Q000378:metabolism; D017753:Ecosystem; D005308:Fertilizers; D005658:Fungi / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology; D025301:Hyphae / Q000502:physiology; D009566:Nitrates / Q000494:pharmacology; D009584:Nitrogen / Q000032:analysis; D011135:Polysaccharides, Bacterial / Q000494:pharmacology; D012987:Soil / Q000032:analysis*; D012988:Soil Microbiology
chemical_list: D005308:Fertilizers; D009566:Nitrates; D011135:Polysaccharides, Bacterial; D012987:Soil; D005947:Glucose; D009584:Nitrogen; C006568:ammonium nitrate