In the Aftermath of Isabel

Ten years ago Hurricane Isabelle roared through Virginia, leaving a new landscape in her wake.  Behind our house, Isabelle uprooted hundreds of mature trees.  In some places, they fell like dominoes, each leafy giant toppling the next.

But in the aftermath of destruction has come regeneration.  The rebirth began immediately after the storm, and continues to this day.

The storm left hundreds of shallow depressions where tree roots once gripped the soil.  Leaves wilted and died on the carcasses of fallen trees.  Large sections of the forest canopy were ripped open, flooding the forest floor with sunlight.

The depressions left by the uprooted trees filled with rainwater, silt and humus .  They became shallow vernal pools, green with algae after the spring rains.  Insect larvae and tadpoles swarmed in the nutrient-rich water.  The following spring, nights were full of croaking, peeping mating calls.  These pools, filled with rotting leaves, are now becoming mossy bogs.

Isabelle made a feast for creatures that feed on dead and dying trees.  Termites and fungi are gradually returning their nutrients to the soil.  In ten more years, the great oaks will be crumbly brown dirt.  Meanwhile, the rotting wood houses millions of ants, beetles and pillbugs, and the occasional raccoon or chipmunk.

Where the canopy was torn away, the forest floor received direct sunlight for the first time in many years.  The contrast between these clearings and sections of forest where the canopy remained intact is striking.  Only a few low plants manage to survive under the shade of the standing trees.  But in the clearings, a profusion of plants now reach upward, gathering as much light as they can.

The low-growing grasses and broadleaf weeds that first colonized the clearings have already been overtaken by taller plants.  The sunny spots are full of blackberry vines, sassafras saplings and pokeweed.  Wild scuppernong and poison ivy climb upward, seeking their share of the light.  Thousands of young tulip poplars strain towards the light like refugees clamoring for bowls of rice.  Some of the young trees are already fifteen feet tall.  Their race upward is a matter of survival.  Only a tiny fraction of the plants in these thickets will survive long enough to flower and produce seeds.  The others, shaded by faster competitors, will die without reproducing.

The profusion of new plants supports new fauna as well.  Squirrels and turkeys will have fewer acorns to gather through the next several decades.  But deer thrive on the abundance of tender new vegetation.  Populations of insects that feed on the young plants  have exploded.  Fuzzy white scale insects and aphids crowd their growing tips.  Caterpillars graze on the foliage.  There seem to be more lightning bugs sparkling in the summer darkness than there have been for years.

Predators that feed on the burgeoning insect population are more numerous too.  The clearings are busy with hunting wasps, yellowjackets and spiders.  Insect-eating songbirds seem to be thriving.  At twilight, squadrons of bats dart back and forth hunting nocturnal insects.

The riotous new growth reminds us of just how amazingly resilient life is, even in the face of disaster.  As the environment changes, some creatures disappear.  But others arrive to exploit niches created by the new conditions.  This resilience is reassuring, as we look at the discouraging signs of our own presence on Earth.

Humans are remarkably adaptable.  We’ve established ourselves almost everywhere on Earth, from tropic heat to arctic ice, from dripping rainforests to parched deserts.  And as we populated the world, we’ve consumed more and more resources, prompting the extinction of other species great and small.  Humanity has roared across the face of the planet like a hurricane.

No creature deliberately sets about to eliminate the resources it needs to survive, of course.  But it’s the nature of every species to exploit its environment and reproduce more of its own kind.  Nature put limits on such expansion, however.  Algal blooms offer a clear example:  When there’s an abundance of nutrients—nitrates and phosphates–in a body of water, the algae population can explode.  The single-celled phytoplankton divide and re-divide.  But eventually, doomed by their own success, they deplete their food supply.  The population crashes.  Dead algae sink to the bottom, consuming the water’s oxygen as they decay.

As our human population pushes against the limits of Earth’s resources, it’s easy to envision our own species heading for such a crash.  We’re awfully ingenious, so technology may be able to stave off disaster for some time yet.  And we do have the benefit of intellectual understanding.  We may yet have time to develop the wisdom to curtail our exploitation of the environment.

Even with zero population growth, it seems unlikely that our planet can sustain billions of humans through the coming centuries.  Our own crash may come through famine, pandemic, war, climate change, some combination of those disasters, or by some new and as yet unforeseen catastrophe.  Human population may not decrease to the point of extinction, but—barring some extraordinary leap of technology yet to be imagined—our population will probably contract to drastically smaller, sustainable numbers.

Given that prospect, it’s encouraging to watch what’s happening in the woodland clearings left by Isabelle.  In the aftermath of great destruction, living creatures of all kinds are repopulating and restoring the damaged environment.

Like all species, Homo sapiens is a transient phenomenon.  But our exit from the planet will leave behind a living world.  Life itself, in all its amazing diversity, has survived and prospered on Earth for three and a half billion years.  From the perspective of that time scale, the span of human existence is just the faintest twinkle of a firefly.

 

copyright by Paul Fleisher 2013