How forests in the U.S. have changed over the past 25 years

How forests in the U.S. have changed over the past 25 years Today’s Video of the Day comes from NASA Goddard and features a look at how forests across the United States have changed over the last quarter-century.

Scientists have used data from the Landsat satellites to compile a look at forest disturbances due to human activity, natural disasters, and natural aging.

According to the research team, the most drastic changes were related to fires in the western United States and logging in the Pacific northwest, Maine, and southeast. As forests mature the average number of small trees tends to decline due to natural competition and the number of large trees increases. 

In just over 100 years the world lost as much forest as it had in the previous 9,000 years. An area the size of the United States. From the chart we see that this was driven by the continued expansion of land for agriculture.

Still, more than half of the world’s habitable land was forested. The turn of the 20th century is when global forest loss reached the halfway point. he annual rate of net forest loss halved from 7.3 million ha per year in the 1990s to 3.3 million ha per year between 2010 and 2015.

Tropical forests are home to great numbers of animal and plant species. When forests are logged or burned, it can drive many of those species into extinction. Also you can find that Tropical forests are cleared to make way for logging, cattle ranching, and oil palm and rubber tree plantations. How forests in the U.S. have changed over the past 25 years as shown in video will show the change over the decades. Also how Much of Earth’s farmland were  once forests.

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By Rory Arnold, Earth.com Staff Writer

Video Credit: NASA Goddard