Comparative ecophysiology of C₃ and C₄ plants

Abstract. In this review we relate the physiological significance of C 4 photosynthesis to plant performance in nature. We begin with an examination of the physiological consequences of the C 4 pathway on photosynthesis, then discuss the ecophysiological performance of C 4 plants in contrasting environments. We then compare the performance of C 3 and C 4 plants when they occur together in similar habitats, and finally discuss the distribution of C 4 photosynthesis with respect to the physical environment, phylogeny, and life form.