Examples of carbon source in the diagram are COMBUSTION AND RESPIRATION while examples of carbon sink are PLANT AND SOIL.
Carbon source refer to any carbon containing molecule that is used by living organisms for synthesis purpose. Carbon sink on the other hand refers to a natural reservoir that stores carbon containing compounds for a long period of time. One basic difference between carbon source and carbon sink is that, the carbon source always release more carbon and thus, shrink in size while carbon sink store more carbon and grow in size.
Examples of carbon sources are: emissions from burning fossils fuels, forest fire and respiration while examples of carbon sink are ocean, plant and soil.
