CalFire points out that vegetation burned by wildfire provides a rich source of nutrients that nourish surviving trees and soil. And periodic fire can be an important way to keep certain ecosystems in balance. Many trees have evolved with fire and some even require it for seed germination; a few species even sport leaves covered with flammable resins manzanita, scrub oak, chamise to encourage fires that help seed the next generation.
National Geographic reports that, surprisingly, wildlife casualties tend to be low during wildfire events, as animals—especially those native to the areas on-fire and evolved to respond to the threat—either burrow in the ground or flee to safer areas instinctively. With the trees now clustered so densely, fires can more easily spread among them and march across a landscape. If a forest is obliterated, it creates problems that can last for years. The resulting burn is also ripe for colonization by invasive species, particularly opportunistic weeds, whose seeds start blowing in from surrounding areas.
By counting trees via satellites, drones, and planes. In a low-severity fire, less than 20 percent of trees will have died. For a high-severity fire, it is over 80 percent. The level of destruction can vary quite a bit within a single fire: The edges might burn more than the interior, or vice versa. Size is a factor too. Wildfire ecologists also analyze the soil structure and chemistry to determine how intense the blaze has been.
The presence of a reddish iron oxide, for instance, indicates that the wildfire burned very hot. Ironically, the unholy blazes that now burn across the western US and Canada are devastatingly destructive to forests and cities—and produce dangerous smoke —but they're also helping tame the fires that will come after them. Controlled use of wildland fires for positive environmental effects is common around the world.
While all fires have the potential to become dangerous to property and life, prescribed, or controlled, burns are planned extensively and performed with tight safety parameters. Humans have been performing such burns for thousands of years and for multiple reasons, but, today, they are mainly used to promote ecological health and prevent larger, more damaging, uncontrolled fires.
It might seem counterintuitive that a fire, which burns plant life and endangers animals within an ecosystem , could promote ecological health. But fire is a natural phenomenon, and nature has evolved with its presence. Many ecosystems benefit from periodic fires, because they clear out dead organic material—and some plant and animal populations require the benefits fire brings to survive and reproduce.
For example, as dead or decaying plants begin to build up on the ground, they may prevent organisms within the soil from accessing nutrients or block animals on the land from accessing the soil.
This coating of dead organic matter can also choke outgrowth of smaller or new plants. When humans perform a prescribed burn, the goal is to remove that layer of decay in a controlled manner, allowing the other, healthy parts of the ecosystem to thrive. Moreover, nutrients released from the burned material, which includes dead plants and animals, return more quickly into the soil than if they had slowly decayed over time. In this way, fire increases soil fertility —a benefit that has been exploited by farmers for centuries.
Several plants actually require fire to move along their life cycles. For example, seeds from many pine tree species are enclosed in pine cones that are covered in pitch, which must be melted by fire for the seeds to be released.
Other trees, plants, and flowers, like certain types of lilies, also require fire for seed germination. Even some animals depend on fire. The sole food source for the endangered Karner blue butterfly caterpillar Lycaeides melissa samuelis is a plant called wild lupine Lupine perennis.
Wild lupine requires fire to maintain an ecosystem balance in which it can thrive. Without fire, the lupines do not flourish, and the caterpillars cannot consume enough food to undergo metamorphosis and become butterflies.
In this way, healthier, post-burn plant populations generally have broad food web effects that trickle up to the foragers and other animals in the ecosystem. Report a problem on this page. Please select all that apply: A link, button or video is not working. It has a spelling mistake. Information is missing. Information is outdated or wrong.
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