Nitrogen dynamics fixation

Gardner, W. S., McCarthy, M. J., An, S., Sobolev, D., SeU, K. S., and Brock, D. (2006). Nitrogen fixation and dissimilatory nitrate reduction of ammonium (DNRA) support nitrogen dynamics in Texas estuaries. Limnol. Oceanogr. 51(1), 558—568. 

Piehler, M. F., Thompson, S., Dyble, J., Moisander, P., Fear, J., and Paerl, H. W. (2002). Biologically mediated nitrogen dynamics in eutrophying estuaries. Assessing denitrification, nitrogen fixation and primary productivity responses to proposed N loading reductions in the Neuse River Estuary 339, Water Resources Research Institute of the University of North Carolina, Raliegh, NC. 

Nevertheless, cereal plants can interact with endosymbionts, capable of nitrogen fixation in other species, and be stimulated in their productivity. The odds of soil life are balanced for some bacteria by their interactivity at rhizosphere level, and a realm of exchanged signals dictates entry into hormonally reprogrammed root sites. Specificity for partner plant species is part of a fine speciation process that actively involves the bacterial nodulation genes, and continues to drive their variation dynamics. 

Paerl, H. W., Fitzpatrick, M., and Bebout, B. M. (1996). Seasonal nitrogen fixation dynamics in a marine microbial mat Potential roles of cyanobacteria and microheterotrophs. Limnol. Oceanogr. 41, 419-427. 

Filamentous cyanobacteria are able to differentiate 5-10% of their vegetative cells into cells specialized in N2 fixation - the heteiocysts or heterocytes. Heterocyst formation does not take place randomly within the filament. Most probably it is a dynamic selection in response to nitrogen deprivation but neither the existence of predetermination nor a combination of both events can be ruled out (Wolk, 1996). 

Lanyon, L. E. 1995. Does nitrogen cycle Changes in the spatial dynamics of nitrogen with industrial nitrogen fixation. Journal of Production Agriculture 8 70-78. 

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