Hi, this is Emily from MinuteEarth.
Earthworms have earned a reputation as nature’s gardeners, because they eat leaves and then
poop their way around underground, returning nutrients to the deep soil.
But some plants, and even whole ecosystems, are actually better off wormless.
举个例子 几千年以来 北美北部的森林的树木长得又高又壮
For example, for several thousand years, the forests of northern north america grew tall
and thick, in part, because there were no worms.
没有蚯蚓的啃食 掉落的树叶堆积了厚厚的几层 它们保护了
Without earthworms to munch fallen detritus, leaves piled up in thick layers, which protected
young tree seedlings from frost and herbivores, and also prevented the trees’ competitors
– smaller, sun-loving plants – from pushing their way through.
但是后来 在1800年 一些来自欧洲的幼虫来到了这里
But, then, in the 1800s, some European wrigglers arrived – perhaps as fishing bait for other
可能是作为其他外来生物的鱼饵 它们入侵了周围的木头 并且迅速开始消灭
new immigrants – and invaded the surrounding woods, where they immediately started devouring
the layers of leaves that had built up over the years.
This moved nutrients from the leaf layer to deeper layers of soil, where it’s harder
for young tree roots to reach, and left tree seedlings exposed to the elements.
结果是 当老树死光的时候 没有足够多的新树替代它们
As a result, when old trees died, there weren’t as many young trees to replace them.
相反 生长更加快速的草和灌木开始长得茂盛了 这也包括了一些
Instead, faster-growing grasses and shrubs began to flourish, including some foreign
species that were good at growing around worms, possibly because they had coevolved together
back in Europe.
The invasive worms have been altering the forests of northern North America for over
And scientists are worried that earthworms, along with an increasing deer population and
a warming climate, could cause massive die-off of the forests in the next 50 years, and someday
help turn them into savannas.
准确来说 是变回稀树草原 因为在最后一个冰河世纪的冰川推平北美北部前
Or rather, BACK into savannas, because way back before glaciers bulldozed northern North
America during the last Ice Age, it was probably a savanna, with its own set of native earthworms.
So the new earthworms, by helping nutrients return to the deep soil, might also be making
room (both figuratively and literally) for the landscape to return to the deep past.
But whether or not that return is a good thing is a whole ‘nother can of worms.
本视频由明尼苏达大学赞助 各个领域 科系的学生和老师
This video was sponsored by the University of Minnesota, where students, faculty and
staff across all fields of study are working to solve the Grand Challenges facing society.
Kyungsoo Yoo教授以及研究生Adrian Wackett正在研究由“全球变爬”所引起的
Professor Kyungsoo Yoo and graduate student Adrian Wackett are studying soil changes caused
by global “worming”.
Lee Frelich和Peter Reich正研究蠕虫是如何与其他侵略性生物相互影响并
Lee Frelich and Peter Reich are researching how worms interact with other invasive species
to change the forest.
另外 Cindy Hale经营着The Great Lakes Worm Watch, 它帮助公众们更了解生态系统中的
And Cindy Hale runs The Great Lakes Worm Watch, which helps the public understand worms’ effects
on the ecosystem.
Thanks to the University of Minnesota for their work and this sponsorship.