Changes in Ecosystems

Science, Grade 5

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© Copyright NewPath Learning. All Rights Reserved. 94-4329 Visit www.newpathlearning.com for Online Learning Resources. Changes in Ecosystems How do ecosystems change? Ecosystems are always changing. Some changes are so big that an ecosystem can die, or change into another kind of ecosystem. For example, if a fire burns most of a forest, its plant life will have to start over again. New growth will start with grass, weeds and small shrubs. Soon young trees, or saplings, will sprout, but it will be many years before there will be tall, strong trees standing in that place again. Environmental Changes & Effects On Organisms Another change that may happen because of a forest fire is that certain populations of animals will leave the area to find food and shelter elsewhere. Other populations that depend on those animals for food will also leave or die out. For example, when trees burn, squirrels and birds leave, and foxes and coyotes follow. When the plants start growing back, animals that eat them will start to return to the forest. Over time, if left alone, the forest ecosystem will come back. Life goes on, only now it’s in a new kind of environment!
© Copyright NewPath Learning. All Rights Reserved. 94-4329 Visit www.newpathlearning.com for Online Learning Resources. Pause & Review Ecosystems can change for many reasons, including natural disasters. Changes in Ecosystems Mount St. Helens erupted in Oregon in 1980. Describe how you think this affected organisms living in the area. _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Think of other reasons that ecosystems might change. Describe some. _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Mt. St. Helens before eruption Mt. St. Helens today Photos courtesy of USGS.