The visible power of trees
In our previous blog we talked about the hidden and often underground power of plants and trees, namely the roots. But what happens to all that good stuff that these roots get from the soil, and how do plants convert this into energy to grow?
Sugar factories
To grow and move, you need energy. People get that energy from the food they eat. Water, oxygen, and a little sunlight (for vitamin D) are also necessary for the body to function properly. Just like us, trees need energy to grow. The special thing about trees, plants and algae is that they can extract this energy from sunlight. We call this process photosynthesis. A concept you probably remember from your biology classes. With the energy from a sunbeam, a tree can bind carbon dioxide (CO2) from the air and water (H2O) from the ground together into sugars (glucose). Oxygen (O2) is the by-product of this. Lucky us. This unique process makes virtually all life on this planet possible.
Plants and trees (and therefore photosynthesis) are indispensable for humans. We owe the oxygen we breathe every day to trees and plants. If you think about it, all energy that we and animals ingest through food is also solar energy passed on by plants [1]. Just like all the fossil energy we use is plant-harvested solar energy. We can therefore think of reforestation as planting sugar factories that run on solar energy, which will give us a lot in the future.
Under the microscope
To find out more about the way plants and trees work, we must zoom in very close on the leaves. These leaves contain two things that are important for photosynthesis: stomata, with which the plant inhales CO2 and exhales O2, and chloroplasts, which provide the green color. In these mini factories, the energy from the sunlight is used to produce sugars, the energy carriers with which the plant can drive its metabolism. Curious what that wonderful micro-world looks like? Then watch this beautiful video from the California Academy of Sciences, where you take a journey into the interior of a Sequoia:
Although you cannot see these stomata and the chloroplasts with the naked eye, by observing plants closely you can see many other special details. For example, you can observe very small hairs on the leaves of the downy birch, and you will see the foliage of the sleeping tree (Albizia) change at sunset because it closes its leaves at night. The nice thing about growing a small tree is that you can clearly see all those processes in action. Who do you give a companion for life?