Photosynthesis: Physiological and Ecological Considerations

23鍚 特 卡 雲 杉The Sitka Spruce (Picea sitchensis) is a large coniferous evergreen tree growingto 50-70 m tall, exceptionally to 90 m tall, and with a trunk diameter of up to 5 m.It acquires its name from the community of Sitka, Alaska.(http://en.wikipedia.org/wiki/Picea_sitchensis)9.3.2 Leaves must dissipate excess light energy24FIGURE 9.12 Excess light energy in relation to a light response curve ofphotosynthetic evolution.12