Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
SEQUENTIAL REDUCTION PROCESSES AND INITIATION OF CH4 PRODUCTION UPON FLOODING OF OXIC UPLAND SOILS
Autore:
PETERS V; CONRAD R;
Indirizzi:
MAX PLANCK INST TERR MIKROBIOL,KARL VON FRISCH STR D-35043 MARBURG GERMANY MAX PLANCK INST TERR MIKROBIOL D-35043 MARBURG GERMANY
Titolo Testata:
Soil biology & biochemistry
fascicolo: 3, volume: 28, anno: 1996,
pagine: 371 - 382
SICI:
0038-0717(1996)28:3<371:SRPAIO>2.0.ZU;2-3
Fonte:
ISI
Lingua:
ENG
Soggetto:
ANOXIC PADDY SOIL; SULFATE-REDUCING BACTERIA; METHANOGENIC BACTERIA; METHANE PRODUCTION; ANAEROBIC-BACTERIA; LITTORAL SEDIMENT; LAKE CONSTANCE; FERRIC IRON; RICE SOIL; METABOLISM;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
44
Recensione:
Indirizzi per estratti:
Citazione:
V. Peters e R. Conrad, "SEQUENTIAL REDUCTION PROCESSES AND INITIATION OF CH4 PRODUCTION UPON FLOODING OF OXIC UPLAND SOILS", Soil biology & biochemistry, 28(3), 1996, pp. 371-382

Abstract

Sequential reduction processes were-Studied in four oxic upland soils(cultivated, forest, savanna and desert soil) which were slurried andincubated under anoxic conditions. NO3- reduction began almost immediately and was followed by reduction of manganese(IV), sulfate and iron(III). The phases of reduction of Mn4+, SO42- and Fe3+ overlapped, with SO42- being depleted long before accumulation of Mn2+ and Fe2+ was finished. CH4 production and growth of methanogenic bacteria began whenall the other reduction processes were finished. Radiotracer experiments showed that CHI was produced from H-2 (29-42%) and acetate. The respiratory index indicated that the acetate was predominantly degraded by methanogenic bacteria. The !ate onset of methanogenesis was not a consequence of limitation by the methanogenogenic precursors, since H-2and acetate were present long before the initiation of methanogenesis. Thermodynamic calculations showed that the concentrations of these substrates were always sufficient to allow exergonic production of CH4 at Gibbs free energies of Delta G < - 30 kJ mol(-1) CH4. However, exergonic production of acetate from H-2/CO2 was not possible. Propionate was also detected in the soil slurries. The redox potential in the soils decreased from > + 400 mV to final values of < - 150 mV, except in the forest soil where the redox potential stayed at + 50 mV. The onsetof methanogenesis and of growth of methanogenic bacteria coincided with redox potentials between + 70 and 0 mV, which is much higher than claimed in the literature. We speculate that the redox-active substances in soil were the signal for methanogenic bacteria to initiate activity.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 09/07/20 alle ore 19:50:11