Biological Dinitrogen Fixation in Chaparral1
نویسنده
چکیده
Microbiologist, Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture, Riverside, Calif. Abstract: Presently available data indicate that biological dinitrogen fixation is responsible for the greatest proportion of nitrogen entering chaparral ecosystems. Dinitrogen fixation by the Rhizobium-legume symbioses is relatively unimportant in chaparral when compared to the possible substantial fixation by free-living soil bacteria and the Frankia-woody shrub (Ceanothus) symbioses. At present, estimates of these processes are scant. Site degradation is possible if management practices adversely affect biological dinitrogen fixation.
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