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ellowstone Park’s forest fire of 1988. The eruption of Mount Saint
Helens in 1980. The deluge of Hurricane Floyd in 1999. It’s hard
to imagine an upside to disasters like these. But Seth Reice, associate
professor of biology and ecology, is asking us to do just that.
Where most of us see only destruction, he sees creative disturbancea
fresh new page in the ongoing story of change.
The ideas in The Silver Lining took shape several years
ago as Reice was measuring the diversity of life in North Carolina
streams. When he selectively removed one species from the habitat,
he found only minor effects on the remaining populations. But then
he decided to shake things up.
"I did an experiment in which I picked up baskets of rocks
from the stream and shook them," he recalls. Tumbling the rocks
eliminated some animals at first, but within two weeks the numbers
of animals had rebounded far beyond their original levels. "So
then I knew that disturbance was the key," Reice says.
Ecologists have long understood that nature takes some kinds of
upsets in stride. Seasonal flooding, for instance, replenishes bottomland
soils and stirs up a feast for the fish and their prey. Even fire
has its advantages. The longleaf pine, patriarch of North Carolina’s
eastern forests, needs fire to expose bare soil to its seeds and
to weed out competitive oaks.
But even in examples like these, Reice says, we traditionally have
looked for a scripted stability, for systems that seemed to be running
according to plan. If the fires or the floods were too disruptive,
we would assume they were problems we needed to solve.
Reice doesn’t see things that way. Disturbance, he writes, isn’t
the exception, it’s the rule. Plants and animals are always recovering
from their last disturbance. And people, Reice thinks, should learn
how to go with the flow.
Remember when Hurricane Fran ripped through our woodlots, felling
the trees? Reice takes us back to the woods for a visit, to check
out what’s popped up to thrive in the light. From the perspective
of the fallen tree itself, or the person whose roof it demolished,
Fran was some very bad news. But for teeming new colonies of animals
and plants, Fran was a breath of fresh air.
Does this mean that natural communities can also bounce back from
the damage that humans inflict? Not always. Unfortunately, Reice
explains, natural systems haven’t evolved to cope with the extremes
of toxic spills, or unbroken acres of pavement, or development that
isolates one natural community from another.
If we don’t allow room for some wildness, we are asking for trouble,
Reice says. In the chaparral of southern California, for instance,
people are building expensive houses on shrub land whose native
vocation is fire. "We really have to incorporate science, and
ecology in particular, into our thinking and planning and behavior
in order to survive in this world," Reice says. "We’ve got
to live with nature, and we’ve got to understand that the nature
of nature is change."
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