Structure and activity of the denitrifying community in a maize-cropped field fertilized with composted pig manure or ammonium nitrate.
One alternative to mineral fertilization is to use organic fertilizers. Our aim was to compare the impacts of 7-year applications of composted pig manure and ammonium nitrate on the structure and activity of the denitrifying community. Mineralization and organization of N, denitrification rates and N2O/N2 ratio were also investigated. Fourteen months after the last application, the potential denitrifying activity (+319%), N mineralization (+110%) and organization (+112%) were higher under pig compost than under ammonium nitrate fertilization. On the other hand, the N2O/(N2O+N2) ratio was lower (P<0.05, n=5) under organic fertilization. These effects of organic fertilization were in accordance with its higher total carbon content and microbial biomass. Fingerprints and clone library analyses showed that the structure of the denitrifying community was affected by the fertilization regime. Our results reveal that organic or mineral fertilizer applications could affect both structure and activity of the denitrifying community, with a possible influence on in situ N2O fluxes. These effects of the fertilization regime persisted for at least 14 months after the last application.
Dambreville
Christophe
C
UMR INRA - UB Microbiologie et Géochimie des Sols, Dijon, France.
Hallet
Stéphanie
S
Nguyen
Christophe
C
Morvan
Thierry
T
Germon
Jean-Claude
JC
Philippot
Laurent
L
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005308:Fertilizers / Q000382:microbiology*; D016946:Gram-Negative Aerobic Rods and Cocci / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D008372:Manure / Q000382:microbiology*; D050901:Nitrate Reductase / Q000235:genetics / Q000378:metabolism; D009566:Nitrates / Q000378:metabolism*; D009609:Nitrous Oxide / Q000378:metabolism; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011897:Random Allocation; D012988:Soil Microbiology; D013552:Swine
D004269:DNA, Bacterial; D005308:Fertilizers; D008372:Manure; D009566:Nitrates; D050901:Nitrate Reductase; D009609:Nitrous Oxide; C006568:ammonium nitrate