ENVIRON 222 Final: Exam 3 Study Guide
Document Summary
2 ingredients for photosynthesis that are typically limiting: Solar radiation (light) is the primary energy source, light availability determines where and when photosynthesis occurs. Nutrient availability is often a limiting factor (n, p, fe) Key factors that affect transmission of light through water: Water absorbs sunlight, very little penetrates depths below ~100m. Only short wavelength, high energy part of spectrum makes it to. Light rays encounter rough, uneven surface and reflect in different directions. In clear water, scattering is limited and most red & yellow light absorbed, reflected light is blue-green. In turbid, i. e. high particle content water, most visible wavelengths are backscattered. The ocean has clear water because it absorbs red and yellow light and reflects blue-green light. Photic zone: zone in the upper ocean where light is of sufficient intensity. Photic zone: zone in the upper ocean where light is of sufficient intensity to support photosynthesis (~1% of the surface value)