Chapter 1 - Photosynthesis in the solar corridor system

Abstract

Photosynthesis is the conversion of light into carbohydrates at the cellular level. Photosynthetic rates are determined by the availability of light, carbon dioxide (CO2), and water for a given temperature regime. There are differences between plant species as classified into C4 and C3 plants, especially in their response to light and CO2. Photosynthesis occurs at the leaf level; however, the overall photosynthetic rate at the unit area level is dependent on the rate of leaf area accumulation by plants and the arrangement of leaves into canopies. Leaf level photosynthesis is affected by the temperature of the leaf and the water and nutrient status that determines the efficiency of the photosynthetic process. At the canopy level, the leaf arrangement becomes the important factor that determines how light is distributed within the canopy, especially diffuse light distribution, and equally important is the effect of the canopy architecture on the movement of CO2 into the canopy to prevent this from becoming a limiting factor. Canopy architecture is a function of row spacing, plant population, crop species, and mixtures of plants, and radiation use efficiency becomes the critical metric of how canopy architecture integrates multiple factors into a quantitative assessment of cropping systems. Photosynthesis is critical to converting light into carbohydrates, and understanding the limitations of this process will guide us in manipulating the leaf and canopy leaf processes to achieve future productivity gains.