Potential environmental controls on nitrogenase activity in biological crusts of the northern Chihuahuan Desert

TitlePotential environmental controls on nitrogenase activity in biological crusts of the northern Chihuahuan Desert
Publication TypeJournal Article
Year of Publication2002
AuthorsHartley AE, Schlesinger WH
JournalJournal of Arid Environments
Volume52
Pagination293-304
Date Published2002
Accession NumberJRN00363
Call Number00803
Keywordsarticle, articles, journal, journals, nitrogenase activity, soil crust, biological
Abstract

We used the acetylene reduction assay to analyse soil nitrogenase activity at the Jornada Long-Term Ecological Research site (northern Chihuahuan Desert, New Mexico, U.S.A.). A three-day irrigation and fertilization experiment showed that water and carbon (glucose) enhanced nitrogenase activity, while NH4NO3 reduced activity. Micronutrient (Mo, Fe, Co) and phosphorus fertilization had no significant effect. A survey of Jornada Basin soils did not reveal an inverse relationship between nitrogenase activity and the ratio of available nitrogen (N) to phosphorus (P), as hypothesized; however, the highest rates of nitrogenase activity were detected in tarbush floodplain soils with a low ratio of available N to P. These findings suggest that labile carbon and inorganic N may exert a stronger control on nitrogenase activity than phosphorus or micronutrient levels.

URLfiles/bibliography/JRN00363.pdf
DOI10.1006/jare.2002.1007
Reprint EditionIn File (03/25/03)