|
|
||||||||
ABSTRACT
The development of indigenous N2-fixing algae in 10 of 12 flooded soils, as measured by acetylene-reduction activity, was stimulated by the addition of phosphate. In P-supplemented flooded soils, these algae generally developed readily at pH 7.3 or greater but poorly at pH 6.5 or less. Iron additions stimulated the activity of inoculated blue-green algae in a phosphate-amended flooded soil of pH 7.9 but not in a soil with a pH of 5.5. Indigenous algae in an acid soil (pH 4.8) were stimulated by CO2. Nitrogen fixation and development of indigenous blue-green algae were correlated with pH and the levels of extractable K and of Ca and Mg in these soils, but not with the concentrations of organic matter, inorganic N, or extractable phosphate and Fe.
1 Contribution from the Graduate Field of Microbiology and Dep. of Agronomy, Cornell Univ., Ithaca, N.Y. 14853. The research was supported in part by a grant from the U. N. Development Program.
2 Graduate Student, Field of Microbiology, and Professor, Dep. of Agron. Present address of senior author: Robert S. Kerr Environmental Research Laboratory, Ada, Ok. 74820.
Received for publication March 12, 1979. Accepted for publication June 13, 1979.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Vadose Zone Journal | Journal of Plant Registrations | ||||
| Journal of Natural Resources and Life Sciences Education |
Journal of Environmental Quality |
||||