EcoWatch
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ANOTHER WARM AND STICKY AFTERNOON PRESSED AGAINST THE SOUTHERN COAST OF THE SEA OF CORTEZ AS I HELD TWO SEA TURTLE HATCHLINGS IN THE PALM OF MY HAND. AS THE SUPPLE UNDERBELLY OF THEIR NEWLY FORMED SHELLS LAY GENTLY AGAINSTMYWRIST, IWONDERED IF THEY COULD SENSE THAT I’D GUIDE THEM SAFELY TO MOTHER OCEAN. AS THE TINY TURTLES PUSHED THROUGH THE SURF, ANOTHER THOUGHT OVERCAME ME.WILL THE HUMAN ASSAULT ON MOTHER OCEAN MAKE HER INCAPABLE OF NURTURING THESE CREATURES TO MATURITY? SINCE THAT DAY, THE GRAVITY OF WHAT IT MEANS TO BE AN ENDANGERED SPECIES CONTINUES TO PULLME CLOSER. ARE HUMANS NEXT?
–Jenna Cavelle, Environmental Affairs |
The Human Factor: Eutrophication, Dead Zones
and the Future of Our Oceans
BY JENNA CAVELLE
I contemplate the extirpation of species that make the California Peninsula, the Sea of Cortez, and the greater Pacific Ocean their home.We are undeniably connected after all. So many extraordinary creatures – humpback whales, stellar sea lions, hawksbill sea turtles, hammerhead sharks, Southern sea otters, the Pacific walrus, Chinook salmon, California condors and kangaroo rats – to name a few. Not just animals but plants too. I consider the fate of the kelp forests and I imagine the remaining moments just before the humpback enters its final fight, the holding on, the ending breath and then extinction.Will it be pollution, habitat destruction, ocean warming or human predation? Will the last walrus drown as a warming sea melts the ice sheet it clings to? Will the Southern sea otter be able to withstand the top-down pressures of an ever-tightening food chain? Will a break in this food web allow sea urchins to completely wipe out kelp forests? Is any of this reversible?
Eutrophication: Oxygen-Poor Ocean Zones
With so many factors driving endangered species to the brink of extinction, the last thing anyone wants to read about is another terrifying phenomenon. I never planned to be an alarmist, but hey, this is alarming stuff. Especially alarming is “eutrophication”, a process which has produced a “dead zone” that expands all the way from mainlandMexico, across the Gulf of California to the desert shores of the Baja peninsula. This dead zone is one of about 150 that have surfaced globally over the past 40 years according to the U.N. Environment Program.
A eutrophication zone is an area in the ocean (or any aquatic habitat) that is oxygen depleted, thus leading to low productivity and ultimately, no life at all.While a dead zone is exactly what it sounds like (dead), its prelude (eutrophication) is not as straightforward.How does eutrophication happen? To understand this,we need to head to a source.
The Yaqui RiverValley is located on the eastern side of the Sea of Cortez opposite the cities of Loreto,Mulegé and Santa Rosalia. This river valley, which drains directly into the Sea of Cortez, is one of Mexico’s most productive coastal farming regions. The agricultural area boasts 556,000 acres of irrigated wheat and is fertilized about four times a year. Here, phosphate and nitrate-rich runoff from and the leaching of chemical fertilizers overload rivers, streams and estuaries. This concentrated effluent eventually makes its way to the Sea of Cortez where the eutrophication process begins.
Once at sea, the “enriched” slurry causes massive algal and photosynthetic bacterial blooms, observed to stretch 19 to 223 square miles and last for days. Soon, a eutrophic zone is created wherein algae and phytoplankton, whose growth becomes limited by available phosphorus and nitrogen, cannot sustain their exploding population.As the photosynthetic organisms die-off, decomposition occurs, using up all the remaining oxygen. These low oxygen, or hypoxic, zones may become so depleted that nothing can survive, creating the “dead” zone. Most fish and other animals cannot survive in this environment; anything that cannot crawl or swim away fast enough will perish.
Inconvenient Choices
It all comes down to what we value the most. Financial security?
Health? Family? Survival as a species?What will happen to civilization
as we know it if the life-sustaining resources we depend on area
destroyed from chemical fertilizers and runoff? I know that most
people aren’t going to have as hard of a time saying good-bye to the
kangaroo rat as Iwill, butwhat about cleanwater and edible food? If we
don’t change soon, wemay be forced to say good-bye to our livelihood
with the same degree of ease and comfort as we would a pesky rodent.
Dead zones don’t just threaten endangered species and biodiversity,
but also the health of the public and the global economy. For
example, red tides can cause outbreaks of life-threatening diseases, such
as paralytic shellfish poisoning, which will shut downmussel and clam
harvesting. In Mexico, recreational and commercial fishing, bothmajor
industries in the Sea of Cortez, face potential collapse. These problems
are not limited to local Bajawaters; they touch the shores of every single
continent on the planet. The environmental and economic impact is
being felt everywhere as environmentalists and economists alike agree
that rising food prices will continue to climb well into the future. If
dead zones increase at the current rate, we can expect greater price
surges, greater seafood shortages and greater toxicity. Evidence linking
global agribusiness to ocean health is irrefutable.
As a direct result of global warming, some scientists believemass
extinctions of terrestrial animals will probably happen first. Any
scientist will tell you that our rivers and oceans are headed for a
disaster so great that humans too, could face extinction. Today’s
average extinction rate is between 1,000 to 10,000 times faster than
it was 60 million years ago. Back then, new species evolved faster
than existing species disappeared. This is why humans witnessed so
much biodiversity when they arrived on the scene. But evolution is
falling behind. It is estimated that 30 million different species
inhabit the planet and each year thousands of those species, ranging
fromtinymicroorganisms to hugemammals, are forever lost. Many
are gone before they are discovered.
Many migrating marine species are increasingly exposed to
eutrophication. Is this the final factor that will finish them off? It
would be foolish of me to pretend that most people in the world
share my affinity for baby sea turtles or any other animal for that
matter.When I look out at our civilization, I see that most people’s
feelings toward nature do not mirror my own. My father once told
me, “Jennifer, if you want to know what matters most to people,
look to the state of their environment and that will tell you all you
need to know. It remindedme of my favorite quote by Ghandi,“The
greatness of a nation and its moral progress can be judged by the
way its animals are treated.”
Here are some things we all can do to mitigate damage to our
rivers and oceans:
1) Buy and eat local foods. Try to avoid foods that produce agricultural
runoff. Buying organic (biodynamic is even better) and local foods,
or even better still, growing your own food, will ensure your food
isn’t contributing to the problem. If you are purchasing food that is
imported from countries and continents other than where you live,
you can rest assured that it is factory farmed,which contributes to
runoff and pollution. The price savings may seem worth it in the
short run, but as you are probably beginning to see, it all comes
back around and ultimately we get what we pay for.
2) If you do choose to grow your own food, don’t use artificial
fertilizers and pesticides. Try composting and using chickens or
organic manure and compost for mulch. You’d be surprised how
many nurseries sell eco-friendly fertilizers and organic compost.
Also, plant drought tolerant, native species in your garden
whenever possible and avoid fertilizing the landscaping as well.
Pick up the book Permaculture in a Nutshell, a concise,
no-nonsense approach to home gardening that yields eco-friendly
food without much cost or time. It is available for under $10 on
www.chelseagreen.comorwww.amazon.com.
3) Avoid putting food items down the garbage disposal that can be
composted instead. This will reduce pressure on the treatment
plant to remove all this waste from the water and the compost can
be reused as a natural fertilizer.
4) Keep reading, discussing and coming up with solutions. Try new
things. Keep what works and change what doesn’t. But most
importantly, approach it all from an honest place as author Derrick
Jensen points out in his compelling book Endgame where he
quotes psychologist, Roianne Ahn, “You know, if we’re going to do
this much damage, the least we can do is tell the truth.” I highly
recommend this and all books by Derrick Jensen for further reading.
Check outwww.DerrickJensen.org for more information.
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