Name: 火灾实际上对森林有益吗？（Are Fires Actually Good For Forests?）
Uploaded: 2021-04-17T03:04:06.000Z
Duration: 3 min 27 s
Description: 【看影片學英語】數萬部 YouTube 影片，搭配英漢字典即點即查，輕鬆掌握單字發音與用法，長久累積看電影不必再看字幕。

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?

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.

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.

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

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 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

Some plants actually need fire and heat to thrive.

Like the giant sequoias in Sierra Nevada region in California.

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.

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

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

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

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

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

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

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.

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

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