The Role of Desert Cryptogams in Nitrogen Fixation
Snyder JM and Wullstein LH. 1973. The Role of Desert Cryptogams in Nitrogen Fixation. The American Midland Naturalist. 90(2):257-265
Several desert cryptogams and associated microorganisms were tested for potential nitrogen fixation using the acetylene-reduction method. Ethylene accumulation was very low for most plants with values between 1.26 and 3.17 n moles ethylene/g/ml/15 days. The highest ethylene assays were obtained for Peltigera rufescens (3720 n moles/g/ml/10 days), Grimmia sp. (52.3 n moles/g/ml/15 days) and Dermatocarpon lachneum mixed with free-living Nostoc spp (162 n moles/g/ml/15 days. Free-living blue-green algae, the Nostoc sp. phycobiont of P. rufescens and Azotobacter-like organisms, were implicated as the nitrogen fixers. However, the role of these organisms as the major providers of nitrogen to the desert ecosystem was questioned.
- Type
- Journal Article
- Authors
- Snyder, J; Wullstein, L
- Units
- ARD
- Keywords
- AIRBIB, desert cryptogams, desert nutrition, Mineralization, Nitrogen Fixation