"Dead Zone" in the Gulf of Mexico

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The last dead zone report I saw estimates it will be smaller this year than in previous years. It does tend to vary in size.

TwoBit
 
I just read the article, that is pretty terrible. But what can be done about it? The farmers need the fertilizers for farming, and even though some people (myself included) joke about farming subsidies, it isn't as if farming is altogether unimportant. Any ideas?
 
squee!:
But what can be done about it?
There was a massive government study on this a couple of years back, and it produced a very interesting and thorough report. I read some of the more pertinent points last spring... as I recall there were several proposed methods to help curb nutrient inputs into the Mississippi. The most realistic of these was to impose a 30% reduction on fertilizer use for corn crops. Studies show that the extra fertilizer isn't helping the corn all that much, so its an easier "sell" with farmers.

However even this plan lacks even the teeniest mote of legislative possibility. Pretty hard to get folks in the midwest to get motivated about a problem in some other state. Kind of like Americans being told to curb their air emissions 'cuz the Canadians across the border are getting acid rain... yeah there's a lot of compassion there.

Nancy Rabalais is the chief scientist concerned with the Dead Zone, you can run internet searches with her name and get neat news articles and quotes, current research, etc..
Occasionally some of the people I work with get involved in this, so I get more than the average person's earful.
 
Something like this just blows me away. The contents of 5800 square miles of ocean dies off (well, except for the little anaerobic guys floating in the nitrogen-enriched sludge) every year and "it's somebody else's problem." What a country. Attention! Attention! There is nothing to see here. Please ignore the dead fish washing up on the shore and go back to munching your ninety-nine cent McMeatChunks and watching Jeff Gordon turn left over and over again. Thank you.

My favorite article on this subject is here.

Warning: This link takes you to a website filled with irreverent humor and occasional profanity. I would not consider it worksafe. Proceed at your own risk.
 
Although by no means condoning the behavior and actions (or more accurately, INactions) responsible for the "Dead Zone", a little clarification on it might be in order.

It's not really a "Dead" zone. Technically its referred to as an "Area of Hypoxia". There is most certainly dissolved oxygen present, just not enough to maintain healthy, long-term aerobic functioning. Clams die. Fish swim away.

The "Dead Zone" is seasonal. It goes away in the winter months when temperatures cool and water mixes more readily. The "problem" thus only exists in the summer months.

Fishkills are usually not a result of the dead zone. Fishkills tend to be caused by localized algal blooms in confined waters. The Dead Zone is neither confined nor very "powerful", so fish usually just swim away and out of it. Heck, CRABS can typically outrun the thing!

The bottom community in the dead zones is not as desolate as the media paints it. The fringes tend to support normal, albeit stressed biota. Deeper inside you'll find most if not all of the fish have left, ditto for the more mobile invertebrates... yes, those commercially valuable shrimp are included here. Capitellid worms capable of tolerating reduced oxygen conditions are pretty common in the sediments, along with certain strains of bacteria and the odd protist.

Once the waters get mixed up, the community reverts back to "normal". That means healthy.

There are in fact no significant impacts on commercial fisheries that can be positively linked to the dead zone. Fishermen may whine and complain, but the science doesn't support it (rather the science supports, AS ALWAYS, overfished stocks). Reports about increased shark attacks on the Gulf coast as a result of the dead zone "squeezing them inshore" are sketchy too.

When it comes down to it, the Dead Zone really is of little concern to the American People, except for the miniscule fraction of fisheries scientists and ecologists like me. The media is making a mountain out of well... gently sloping flatland. What IS of potential concern however is that the dead zone tends to get bigger over the years, and that eventually it MAY start to move into areas that are of economic or social importance. Like inshore.
 
squee!:
I just read the article, that is pretty terrible. But what can be done about it? The farmers need the fertilizers for farming, and even though some people (myself included) joke about farming subsidies, it isn't as if farming is altogether unimportant. Any ideas?

In my opinion farm subsidies and other programs are a bit of a mess. And I grew up on a farm and ranch that my parents still operate so I am not anti-farmer/anti-rancher. There are programs to take land out of production to both reduce crop production in order to help support prices and also to take land that is marginal in terms of soil quality or is overly prone to wind and water erosion, and should not be farmed at all, out of production.

But these programs are generally short lived with the land going back into production. And in many cases no changes to the land are allowed that would result in it being used for something else (for example adding a stock damn to enable the land to be permanently used as grazing land rather than to be re-tilled and farmed.)

The irony here is that if crop prices are higher, it becomes more economical for farmers to break up and farm marginal land or to use fertilizers to boost crop production from the land they have remaining in production (often using the land set aside payments to pay for the fertilizer.)

The solution would be a fairly complex approach using some fairly sophisitcated systems analysis techniques to identify the various feed back loops and then imposing some manadatory land use legislation to obtain optimum results in terms of price, production, and sustainability. The problem with that is that our politicials are just not going to do that as the various parties have competing interests - consumers want cheap food, farmers want to make a living, corporate farms want to maximize profits and suppliers want to sell farm equipment, seed, fertilizer and pesticides, and farm bureaus want to develop and manage farm programs.

Only a portion of the problem is actually the farmer/rancher's fault and they are in many ways encouraged by the government and economic forces to mis-manage their operations. Before fertilizers were commonly available crops were rotated to use the by products of different crops to maintain healthy levels of nutrients in the soil, For example wheat, corn, and alfalfa crops would be rotated and the land would laso be left fallow in the cycle for a season as well. Some farmes would also run cattle and would then use the manuer for fertilizer. These techniques allowed sustaineable production and conserved the land over the long term without requiring chemicals. This approach is probably very close to what a large scale systems analysis would indicate is the optimum approach - this particular land use system developed over time for the simple reason that it worked.

The ready availability of chemical fertilizers however has changed the picture as it allows potentially higher yield and continuous production of what ever crop will bring the most at market but at increased cost to the farmer and with some unwanted ecological consequences and in the long term some serious issues with chemical residues in the land itself.

When I grew up on my parents farm and ranch, the point was made that a farmer or rancher's only real asset is the land and the first priority is to ensure the land stays healthy. This is not at all what I see today in the majority of cases. For example we have had a fairly serious drought the last few years and I have seen pasture land in the area severely overgrazed by ranchers who are choosing to maintain excessively large herds in the interest of short term profits rather than the long term health of the pastures. The government contributes to this problem by providing "disaster" relief when politicians see or read reports of devastated pastures and then ascribe it to the drought (which is a natural and cyclical thing that native grass lands have survived quite nicely for eons) instead of to poor ranch managment by ranchers who then promoting themselves as "victims" rather than poor managers who deserve to go out of business. The problem is not the drought, but rather a generation of ranchers who have forgotten that their real asset is not the herd but rather the land.

So in the end the problem is greed by all parties, not fertilizer (which farmers really don't need, except on land they should not be farming anyway). And greed has developed in our society as people on average are much more focused on their own well being and their own self interests than they are on the well being of their children and the legacy they will be leaving them - and that pretty much sums up the root cause of virtually every environmental issue.
 
Archman & Aqua,

Thanks for the info. I appreciate the perspective, especially with regards to greed. Have our attention spans become so short that we've forgotten the lessons of previous generations?
 
YakSpout:
Archman & Aqua,

Thanks for the info. I appreciate the perspective, especially with regards to greed. Have our attention spans become so short that we've forgotten the lessons of previous generations?


Yeah, thanks for putting things in perspective. I suppose it is not the first time the media makes something seem a lot worse than it is. :wink:
 
I'm not really sure the media is hyping the dead zones. Or maybe I missed it in the ongoing blather over who did what in 1972.

Most people aren't aware that there are dozens of dead zones in many costal areas. In my neck of the woods, the Chesapeake Bay is more dead zone than not. Is it a problem? Ask an Oysterman, if you can find one.

Scientists don't just go out and find dead zones. They usually show up to investigate when fishermen start hauling up pots of dead crabs and such.

Such was the case with a curious new hypoxic area off the Oregon coast. This one doesn't seem to be caused by a typical nitrogen enrichment and phytoplancton bloom/dieoff cycle. This one is a "natural" dead zone caused by shift in currents that is bringing in deep water from the sub arctic.

Sure the dead zone itself is not much ... but a shift in the California current? That might be something to think about.
 
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