Primary productivity: Plants at work

Plants use a process called photosynthesis to convert absorbed sunlight into energy. During photosynthesis the chlorophyll in plants absorbs red and blue light and reflects back green light and “near-infrared” light – which is why the parts of the plants containing chlorophyll appear green. Measuring this near-infrared light allows us to track changes in vegetative life. Parks Canada staff use data from satellites to observe the amount of near-infrared light being reflected by vegetation and determine the amount of vegetation growth in the park.

Changes in the volume of plant growth of a forest ecosystem could indicate disturbances, such as insect defoliation, and allow park staff to determine if management actions are required. Specialists monitor landscape level changes and calculate the volume of annual plant growth. Satellite images of the forest and grasslands within Elk Island National Park have been gathered for several years. These images are used to create baseline data to which future changes in plant growth can be compared too.