What in the world is Vegetation Index? It is–in its simplest form–a measurement of the density of vegetation on the planet. In short, we want to increase the density of vegetation on earth, as more trees and forests, grasses and prairies, and agricultural crop cover all help convert and store more atmospheric carbon, retain more moisture in the soil, and reduce the amount of heat reflected off the ground.
There are several ways to increase the earth’s vegetation index.
- No-till agriculture. Instead of plowing up millions of acres of soil and leaving it exposed, keeping the soil surface productive using cover crops is one way to improve our vegetation index.
- Green roofs. Urban areas with commercial buildings bearing white roofs reflect significant amounts of light and heat back up into the atmosphere. Covering a roof with plants helps to reduce that reflected light and heat and increases our vegetation index.
- Reducing heat islands. A heat island is a location that is hotter than surrounding areas–typically urban centers. But on a smaller scale, a typical parking lot can be a heat island. Large asphalt areas absorb heat and then radiate it back up into the atmosphere. If we simply changed the amount and type of trees that are planted in and around asphalt parking lots, we could significantly improve their vegetation index. Broad-crowned trees could cover much more surface area than small or columnar trees that are often used.
- Prune less foliage from trees. Trees are often over-pruned. There is a proper way to prune trees, and it essentially involves keeping them looking completely natural, and simply correcting structural issues and other objectives. In general, a good percentage of growth to prune out of a tree is approximately 20% of the volume of its foliage. Unfortunately, trees are often severely over-pruned, greatly reducing their vegetation index. When we are talking about millions of trees that are pruned annually in our urban and community forests, even a 2% improvement is significant to increasing our vegetation index.
- Keep plants healthy. A healthy plant, with a vigorous, full, green canopy, is far more effective at absorbing light than a sickly plant with yellowing leaves or a sparse canopy. Granted, it is hard to imagine one plant making much of a difference, but collectively, if we took better care of our plants, trees and grasses, it could have a positive impact on the vegetation index.
What other ways can you think of to improve our vegetation index?