The reversal was unintentional, mostly due to the collapse of the Soviet Union and command economies of the Central and Eastern European states, which could no longer afford to purchase fertilizers for farming. There are many proposed solutions to the Gulf of Mexico’s dead zone problem: cover crops, wetland construction, fertilizer reduction, and so on.
This would reduce water use from five large aquifers along the Mississippi River network, and would completely stop most agricultural runoff from converted farms. This single investment could lead to a range of revenue streams to supply future subsidization of organic farm conversions and green infrastructure developments.
With the return of a controlled fishing industry that allows aquatic life to rapidly rebound, a boost in tourism to the area, along with a small tax on the increased supply of vegetable output from hydroponic farms that operate year-round and produce higher quality vegetables at a much faster rate, funds can be raised for everything from wetland construction to biogas construction subsidies for livestock farms. Though we have created an environmental disaster around our coasts, smart development, effective use of economic schemes, and updating the United States’ farming infrastructure and practices can greatly restore the health of the dead zone that has nearly enveloped all the Eastern seaboard and Gulf Coast.
Or you can download these pages in several formats that you can include in your course website or local Learning Management System. The dead zone in the Gulf of Mexico is primarily a result of runoff of nutrients from fertilizers and manure applied to agricultural land in the Mississippi River basin.
Runoff from farms carries nutrients with the water as it drains to the Mississippi River, which ultimately flows to the Gulf of Mexico. If a number of nutrients reaching the Gulf of Mexico can be reduced, then the dead zone will begin the shrink.
Since 2008, the Hypoxia Task Force, led by the U.S. Environmental Protection Agency and consisting of five federal agencies and 12 states, has been working to implement policies and regulations with the aim of reducing the size of the dead zone in the Gulf of Mexico. Cover Crops: Planting of certain grasses, grains or clovers, called cover crops can recycle excess nutrients and reduce soil erosion, keeping nutrients out of surface waterways.
Watch the following video from the US Department of Agriculture about strategies to reduce nutrient loading into the Mississippi River: Video: Preventing Runoff Into The Mississippi River (1:44) Review the graphs below and answer the questions.
Figure 4.2.11 presents the size of the hypoxic zone in the Gulf of Mexico from 1985 to 2014. The U.S. Environmental Production Agency led a task force in 2008 that identified a goal to reduce the five-year average of the size of the dead zone to less than 2,000 square miles by 2015.
Answer: The annual total nitrogen and phosphorus loading to the Gulf of Mexico has remained high from 1980-2011. In order to reduce the size of the dead zone, the annual nutrient loading needs to decrease.
Propose some possible strategies that could contribute to a reduction in the size of the hypoxic zone. Credit: Data source: Nancy N. Rabelais, LEMON, and R. Eugene Turner, LSU.
Funding sources: NOAA Center for Sponsored Coastal Ocean Research and U.S. EPA Gulf of Mexico Program. Over a twenty-year period, the GEF invested $97.70M and there was an additional $288.76M of co-financing in pollution-reduction measures targeted at reversing a massive 40,000 km2 dead zone that had formed in the northwest shelf of the Black Sea.
These investments have been largely successful: nitrogen and phosphorus emissions have fallen by 20% and 50% respectively over the last 15 years, and the number of recorded benthic species doubled between 1980 and 2000 (STAR, 2011). At the same time two pivotal events accelerated the institutional reforms needed to reduce pollution levels in the Black Sea; 1) the economic collapse in Central and Eastern Europe during the 1990s, which led to a decrease in agricultural production and nutrient use; and, 2) increased obligations for countries to comply with strong environmental legislation in order to be granted accession into the European Union.
The Strategic Investment Fund and the UNDP regional projects played a central role in helping partner countries reach these stringent standards. Some lessons learned from these investments include the importance of: 1) bringing freshwater and marine stakeholders together to apply a true source-to-sea approach; 2) investing in capacity development for decision makers to help accelerate the formulation of new policy and the adoption and implementation of new regulatory and economic instruments; and, 3) having the patience and foresight to allow for the long time frame (typically 15-20 years or more) necessary to transform policy through science-based integrated planning, barrier removal, and market transformation.
Over 20 years of investment, these projects helped reform national agricultural policies, improved industrial and municipal wastewater treatment, rehabilitate ecosystems, and strengthened the region’s legislative framework and related enforcement. Falling ocean oxygen levels due to rising temperatures and influence from human activities such as geochemical use is an increasingly widespread problem.
Considering that the sea floors have taken more than 1,000 years to recover from past eras of low oxygen, according to a recent University of California study, this is a serious problem. Ocean regions with low oxygen levels have a huge impact on aquatic organisms and can even destroy entire ecosystems.
By examining seafloor sediments the researchers assessed how global warming affected sea life during the transition from the last ice age to the more-recent interglacial period, between 17,000-3,000 years ago. What the study found was that within only 130 years the oceans underwent devastating changes that led to complete collapse of invertebrates on the seafloor.
So the current growth of dead zones could leave drastic and long-lasting changes to marine life biodiversity. Studies have shown that populations of mid-water fish such as Pacific hake decreased by up to 60% during periods of low oxygen off the coast of Southern California.
Even the fish that can survive in dead zones are not faring well: large numbers of female Atlantic Croaked have been found to be growing testes-like organs instead of ovaries, a sexual deformation which causes infertility. To prevent the possibility of a 1,000-year (or longer) recovery period from a dead zone seafloor, we need to be much more aware of how the various environmental aspects are connected.
Image: A school of barracuda swims off the Malaysian island of Ibadan in Celebs Sea, east of Borneo, December 7, 2007. Fertilizer applied in the Midwest creates vast algal bloom, which, in turn, uses up the oxygen in the surrounding waters.
Organic and sustainable farming methods offer strategies to lessen fertilizer contamination of the Mississippi River and shrink the dead zone. Farm field runoff makes its way to the Mississippi River Source: USDA ARCS, Lynn Beats At the bottom of the Mississippi River’s journey from Lake Itasca to the Gulf of Mexico lies the world’s largest dead zone.
This particular dead zone at the Mississippi’s mouth is a swath of ocean, big as New Jersey at its peak, that’s choked for oxygen. The dead zone most directly harms people and industry along the Gulf Coast, but states to the north had the biggest hand in causing it.
The river basin is more than 1.2 million square miles in size, and a big chunk of it is farmland. Farmers have reduced field erosion in recent decades through precision agriculture techniques and conservation tillage, said Patrick Belmont, a watershed researcher at Utah State University.
Scientists quantified the effectiveness of common methods to curb nitrogen and phosphorus levels in 2016 study by the Center for Watershed Protection. Across the three states, methods to manage and reduce the amount of phosphorus and nitrogen put into the soil cut the nutrient levels by up to 24 and 26 percent, respectively, the study found.
Taking mass acreage of farmland out of production, or converting it to wetlands or perennial crops, would cut the dead zone fastest. McDonald said she thinks the best bet is to focus on how to get the most plant cover on the landscape for the longest period of time.
Solutions like cover crop are an option because they rejuvenate the soil and clean out nutrients before they reach the Mississippi River. A dead zone is a large area of water that contains very low concentrations of oxygen, and therefore cannot support any life forms living there.
With little oxygen remaining in the lower water layer, no organisms are able to live there, and they either move away to a more hospitable environment, or die. All of these factors impact the amount of nutrients that are carried into coastal areas and other water bodies where algal blooms occur, forming dead zones.
It has been estimated that there are more than 400 dead zones around the world, including in North and South America, China, Japan, and Australia. Local communities and economies that depend on fishing for their livelihoods can also be negatively impacted by dead zones.
Wetland ecosystems can also be restored along rivers, lakes, streams, and coasts that help to capture and filter out pollutants that would otherwise end up in water bodies and reach coastlines. Because animals and plants need dissolved oxygen to live, entering a dead zone causes them to suffocate and die.
Dead zones are found in rivers, lakes, oceans, ponds, and even Aquarian. Surviving fish suffer reproductive problems, with low egg counts and spawn rates.
Dead zones mainly occur in coastal regions near watersheds, particularly in high population areas. The largest dead zone in the world is located in the lower portion of the Black Sea.
Temporary dead zones are hypoxic regions that last for hours or days. Died cycling hypoxia refers to dead zones that occur during warm months, but the water is only hypoxic at night.
Usually, the bloom itself is non-toxic, but an exception is a red tide, which produces natural toxins that can kill wildlife and harm humans. Water pollution is the primary human source of the nutrients that cause eutrophication and dead zones.
Fertilizer, manure, industrial waste, and inadequately treated wastewater overload aquatic ecosystems. Nitrogen compounds from automobiles and factories are returned to water bodies through precipitation.
When the weather is clear and sunny, the oxygen production outperforms nighttime consumption. A string of cloudy days can reduce the ultraviolet levels enough to even the score or even tip the scales so more oxygen is used than produced.
This occurs so rapidly sometimes even fish can 't swim outside a zone fast enough to escape death. Sunlight reaches the algal layer, but it can 't penetrate the growth, so photosynthetic organisms below the algae die.
GOLF / Getty Images Dead zones in an aquarium or pond are preventable. Regulating the light/dark cycle, filtering water, and (most importantly) not over-feeding can help avoid hypoxic conditions.
In lakes and oceans, it's less a matter of preventing dead zones (since they exist globally) and more about reversing the damage. For example, a large dead zone in the Black Sea all but vanished in the 1990s when farmers couldn't afford chemical fertilizers.
The reduction of industrial effluents and sewage along the Rhine River has reduced nitrogen levels by 35 percent in the dead zone in the North Sea. Clean-up along the San Francisco Bay and Hudson River have reduced dead zones in the United States.
Fixing that dead zone will require dramatic changes by farmers, industries, and cities all along the coast, the Mississippi River, its delta, and its tributaries. Census/Frederic Iron / Getty Images Today's environmental problems are so big they can seem overwhelming, but there are steps each individual can take to help reverse dead zones.
Every bit of water you flush away eventually returns to the watershed, bringing man-made pollutants with it. Burning wood or using fossil fuels releases nitrogen into the air which will make its way into the water.
The biggest steps most individuals can take are driving less and reducing power consumption in the home. Dead zones are places in the ocean or other bodies of water characterized by having a low oxygen concentration.
When the algae die, decomposition depletes the oxygen, killing animals within the zone. This is a major undertaking that requires cooperation between legislators, farmers, industries, and cities.
“Predicting impacts and recovery of marine farm sites in Stewart Island New Zealand, from the Findlay-Watling model”. Reconstructing an 180-yr record of natural and anthropogenic induced hypoxia from the sediments of the Louisiana Continental Shelf.