Students will identify the positive and negative effects of grassland fires on plants.
Students will describe some of the changes fire can make in ecosystems.
Students will list reasons for the importance of preventing human caused wildfires.
Students brainstorm positive and negative effects of grassland fires and create murals showing changes from fire in grassland ecosystems. NAAEE Learner Guidelines:
2.1 A), D)
2.4 A), E)
3 B) Background:
For a period of time, all fires were suppressed or vigorously fought. Today many fires are allowed to burn as part of a natural cycle within forest and grassland ecosystems. Research has shown that the lack of periodic fire in many wild areas increases risks to society and the environment. In remote areas, some agencies monitor lighting-ignited wildfires and allow them to burn as long as they stay within acceptable limits of fire behavior and location. However, wildfires near populated areas still are fought aggressively. There is a movement to use “prescribe” fires under some conditions and in some places in an effort to replicate natural cycles that contribute to maintaining healthy ecosystems. Such “prescribed burns” are planned and tended by qualified resource managers.
Fires can have negative as well as positive effects. If a fire is too large, too hot and burns too fast and, wildlife cannot easily move to safety. Individual animals may die or be displaced from their habitats. Short-term and long-term loss of vegetation can have a variety of effects, including loss of food and shelter for wildlife and increase in silting and sedimentation in the waters.
Some positive effects and benefits of fire are that it:
Provides habitats for species primarily dependent on fire-driven ecosystems such as Kirkland’s warbler;
Increases soil productivity by releasing and recycling nutrients in litter and undergrowth;
Prepares soil for germination of some seeds.
Poster paper, art supplies.
See “Smokey Bear Said What?” in Project WILD for additional information.
Begin this activity with a discussion about forest and grassland fires. Student’s reactions may be negative at first. Point out that while fire may be detrimental to some wildlife and plants, fire may benefit them, too.
Brainstorm positive and negative effects of grassland fires. Post this on a board for all to see.
Divide the class into groups of 2-4 students. Each mural should portray the area before, during, immediately after and five years after a fire.
Describe two benefits of wildfire to an ecosystem.
Describe a short term and long term effect to a rancher if fire occurred in a pasture used for grazing livestock.