ISSN:
1432-1939
Keywords:
Cyanobacteria
;
Fire
;
Acetylene reduction
;
Ash
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary 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 N:available P ratio (aN:P) across a range of concentrations. Nitrogen fixation rate could be related empirically to aN:P 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.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00378663
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