https://eprints.nwisrl.ars.usda.gov/id/eprint/451 2017-01-13T20:39:24Z info:eu-repo/semantics/descriptiveMetadata https://eprints.nwisrl.ars.usda.gov/id/eprint/451/ Fixation of Isotopic Nitrogen on a Semiarid Soil by Algal Crust Organisms Mayland, H.F. McIntosh, T.H. Fuller, W.H. Nitrogen Mass Import - autoclassified (may be erroneous) Semiarid desert algal crust organisms were found to fix N2 when exposed to an atomosphere which contained isotopically enriched N. Significant quantities of the N isotope were detected in the total crust N after 3 days of incubation under field-simulated conditions. Net N2 fixation rates by the algal crust organisms were 0.16 and 0.10 lb of N/acre of crust surface per day under continuous wet and cycling wet-dry conditions, respectively. Net fixation of N under field-simulated conditions adequately compensated for the removal of N by livestock. The rate of N2 fixation under field-simulated conditions increased linearly for at least 520 days. The amount of N in the algal crust was doubled during this time. No net N change was observed in dry crusts. Growing algal crusts contained 1% to 2% of the total N as extracellular NH4-N. Excretion of some fixed nitrogen was suggested by the isotopic enrichment of the extracellular N fraction and uptake of labeled N by grass seedlings (Artemesia sp.) growing on incubated crusts. 1966 Article NonPeerReviewed application/pdf en https://eprints.nwisrl.ars.usda.gov/id/eprint/451/1/56.pdf Mayland, H.F. and McIntosh, T.H. and Fuller, W.H. (1966) Fixation of Isotopic Nitrogen on a Semiarid Soil by Algal Crust Organisms. Soil Science Society of America Proceedings. 30(1):56-60. 0056 0056 info:eu-repo/semantics/objectFile info:eu-repo/semantics/humanStartPage