Effects of available P and N:P ratios on non-symbiotic dinitrogen fixation in tallgrass prairie soils.
Oecologia
; 79(4): 471-474, 1989 Jun.
Article
em En
| MEDLINE
| ID: mdl-28313480
ABSTRACT
Prescribed burning is a major control over element cycles in Tallgrass prairie (Eastern Kansas, USA). In this paper we report potential effects of fire on nonsymbiotic nitrogen fixation. Fire resulted in additions of available P in ash, which may stimulate nitrogen fixation by terrestrial cyanobacteria. Cyanobacterial nitrogenase activity and biomass responded positively to additions of ash or P in laboratory assays using soil. Further assays in soil showed that cyanobacteria responded to changes in available Navailable P ratio (aNP) across a range of concentrations. Nitrogen fixation rate could be related empirically to aNP via a log-linear relationship. Extrapolation of laboratory results to the field yielded a maximal estimate of 21 kg N ha-1 y-1. Results support arguments from the marine and terrestrial literature that P availability is central to regulation of ecosystem N budgets.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Oecologia
Ano de publicação:
1989
Tipo de documento:
Article
País de afiliação:
Estados Unidos