Carbon balance, productivity, and water use of cold-winter desert shrub communities dominated by C and C species.

Common generalizations concerning the ecologic significance of C photosynthesis were tested in a study of plant gas exchange, productivity, carbon balance, and water use in monospecific communities of C and C salt desert shrubs. Contrary to expectations, few of the hypotheses concerning the performance of C species were supported. Like the C species, Ceratoides lanata, the C shrub, Atriplex confertifolia, initiated growth and photosynthetic activity in the cool spring months and also exhibited maximum photosynthetic rates at this time of year.

Mineral ion composition and osmotic relations of Atriplex confertifolia and Eurotia lanata.

Periodic collections of Atriplex confertifolia and Eurotia lanata leaf tissue throughout the growing season were analyzed for osmotic potential, water content, and concentration of Na, K, soluble Ca, Cl, and SO ions. Ionic concentrations of these two species exhibited marked similarities to corresponding values for European members of the same genera. Atriplex confertifolia, like many other Atriplex species, behaves as an alkali halophyte and accumulates Na, while E.