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  • With California facing a megadrought, many fear that fire season this year will be bigger

  • and more devastating than previous years.

  • But is there a way we could fight forest fires, with fire?

  • Hey guys Julia here for Dnews

  • With drought drying up the west, the threat of wildfires is more dire than ever.

  • In the past five years, many states have seen the biggest fires in 50 years.

  • Previous wildfires have caused millions of dollars in damage to homes and property.

  • Some fires even were deadly.

  • So it's no wonder the US Government spends billions every year to fight them.

  • But unfortunately it's not a simple case as some bear in a hat wants us to believe.

  • Historically, places like California saw big burns every year.

  • But as more and more people moved west, forest fires had to be stopped.

  • But decades of fighting forest fires actually made things worse for a little while.

  • It made some ecosystems less diverse.

  • And suppressing natural fires led to a buildup of debris and clutter on the forest floor,

  • setting the stage for disasters to come.

  • After the Yellowstone fires of 1988 and the fire season of 2000, people began to understand

  • that some ecosystems NEED fire, they've evolved to make use of it.

  • Fire is part of their natural lifecycle.

  • Fire benefits an ecosystem in a few ways.

  • Sometimes it breaks down nutrients in a flash, literally.

  • Nutrients from leaves, logs, and other debris that otherwise would have taken years or decades

  • to break down and return to the soil.

  • Some plants actually need fire and heat to thrive.

  • Like the giant sequoias in Sierra Nevada region in California.

  • They need the heat of fire to reproduce!

  • Sequoias make large cones, that only open and disperse their seeds when they dry up.

  • One of the primary ways they dry out, is from, you guess it kids, the heat of a fire.

  • And they aren't the only ones.

  • In the Pinelands in new jersey, there's several species that need fire to reproduce

  • including the pygmy pitch pine.

  • This small plant evolved a few ways to fight fire.

  • It's got thick bark that protects it from the heat.

  • But if the trunk happens to be damaged by fire, it can regrow sprouts from the wound!

  • Fire doesn't just help things grow, sometimes its powers of destruction, are for good!

  • By clearing out clutter, it can destroy invasive species or harmful insects and can even open

  • up the dense forest canopy to allow sunlight to reach the forest floor, so more things

  • can grow.

  • It also creates new areas of grasslands which some species of animals depend on for shelter

  • or food.

  • so what do we do? is there a way we can protect our homes while still allowing these delicate

  • ecosystems to thrive?

  • Well every year some forestry services practice what's called controlled burn or prescribed

  • fireY.

  • yes there are people whose job it is to set fires.


  • But it's a tricky business.

  • The conditions have to be just right or a fire could quickly get out of control.

  • If conditions are too dry, the fire can get too hot or too big too quickly, and there

  • are a few cases of controlled burns getting out of control.

  • If too damp, well nothing's going to burn.

  • In the Pinelands of New Jersey parameters for burning are tight, like under 55 degrees,

  • wind speeds of 7 to 12 miles per hour and about two or three days since the last rainfall.

  • In some years, they can burn up to 22,000 acres of forest.

  • And this policy seems to be helping.

  • One study published in the journal Ecosphere, found that areas that were purposely burned

  • had twice as many native plant species as nonburned areas after 10 years.

  • And other studies from the Ecological Society of America show that prescribed burns reduce

  • the severity of wildfires.

  • But these are small, very well managed, controlled burns.

  • So it seems it really pays to fight fire with fire.

  • But only if you're a professional with a permit, so still listen to that bear in a

  • hat.

With California facing a megadrought, many fear that fire season this year will be bigger


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B1 中級 美國腔

火灾实际上对森林有益吗?(Are Fires Actually Good For Forests?)

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    joey joey 發佈於 2021 年 04 月 17 日