"451","12","archive","1",,,"disk0/00/00/04/51","2010-11-20 21:52:47","2017-01-13 20:39:24","2010-11-20 21:52:47","article",,,"show","","","","","","","","","","","0",,,"Mayland","H.F.","","","","",,,,,"","","Fixation of Isotopic Nitrogen on a Semiarid Soil by Algal Crust Organisms",,"pub","soiche_nitr","d_unclass",,,"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","published",,,"0056",,"",,"public",,,,"Soil Science Society of America Proceedings","30","1",,,"56-60",,,,,,,,,,,,,,"unknown",,,,,,,,,"","","",,"","",,,,,,,"",,,,
"451",,,,,,,,,,,,,,,,,,,,,,,,,,,"McIntosh","T.H.","","",,,,,,,,,,,,"autoclass",,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
"451",,,,,,,,,,,,,,,,,,,,,,,,,,,"Fuller","W.H.","","",,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,