ABSTRACT
Nitrogen availability was also determined to be a factor limiting plant biomass production in inland saline areas. However, when nitrogen fertilization of the zone with inhibited growth is carried out, a significant increase in biomass production occurs. Fertilization with nitrogen increased plant production as well as water uptake in salt marshes, and the increased root growth should serve to increase the oxygen supply available for root growth. A number of investigations have been carried out to determine whether nitrogen availability was a limiting factor determining the biomass production of Spartina alterniflora, the dominant species on Atlantic and Gulf coast salt marshes of North America. Factors limiting nitrogen uptake could produce symptoms of soil nitrogen deficiencies even when soil nitrogen concentrations were adequate for growth. Experiments will have to be designed to take into account the many interactions involved in the nitrogen nutrition of halophytes and how these relate to biomass production in salt marsh habitats.
