Hypothesize how global climate may affect photosynthesis in land plants? in optimum growing conditions where resources (e. g. water, nutrients) are unlimited, which type of plant (c3, c4 or cam is most likely to benefit from global warming? in terms of carbon fixation. edu

Rice Research Station, Kerala Agricultural University, Kochi,India. Climate change affects plants in many different ways. Increasing CO(2) concentration can increase photosynthetic rates. Increasing temperature also affects photosynthesis, With increasing temperature, vapour pressure deficits of the air may increase, with a concomitant increase in the transpiration rate from plant canopies. However, if stomata close in response to increasing CO(2) concentration, or if there is a reduction in the diurnal temperature range, then transpiration rates may even decrease. Soil organic matter decomposition rates are likely to be stimulated by higher temperatures, so that nutrients can be more readily mineralised and made available to plants. This is likely to increase photosynthetic carbon gain in nutrient-limited systems. All the factors listed above interact strongly so that, for different combinations of increases in temperature and CO(2) concentration, and for systems in different climatic regions and primarily affected by water or nutrient limitations, photosynthesis must be expected to respond differently to the same climatic changes..