Brittany's Blog

A Final Look at Algae

2010-05-04T13:39:00.000-07:00

As technologies are developed and spread across the world, the effects of these technologies on the environment are becoming more apparent. Nations all over the world are changing agricultural practices, and how people raise and handle their crops is becoming more mechanized for peoples with the money to effect the change. Most of all, agrichemicals, such as ammonium nitrate, are becoming more widely used as a means to obtain higher yields. Unfortunately, with the advancement in any technology, comes a price. When any nutrient-rich chemicals leach into waterways, it is bound to impact the environment. One such impact is on algae populations. Chemicals such as ammonium nitrate and phosphates used by humans are over feeding algae populations in oceans in lakes, causing damage to aquatic ecosystems and creating serious problems for fishermen, who rely on the ocean as a means to live.

What is Algae and Why is it a Problem?

Algae are a type of photosynthetic life form that inhabits aquatic environments. Although many people would characterize algae as a type of plant due to its use of the sun for energy, most species of algae are actually protists. Different species can live in either fresh or salt water environments. Algae tend to favor the surface of a body of water, as less sunlight penetrates the water at greater depths. Algae are an integral part of aquatic ecosystems, providing food for fish and other forms of sea life. Many species of algae are helpful or benign in an area, but some species produce toxins or are more prone to take over an ecosystem. When an environment contains the right amount of resources, harmful algae can often bloom, choking out much of the life that had once occupied that region.

A common term for one type of bloom is “red tide.” Red tide occurs when poisonous one or more poisonous varieties of dinoflagellates bloom in an area. Dinoflagellates make up a large portion of algal species. It is important to note that not all dinoflagellates are toxic. Red tide is so named because it tends to turn the water red or reddish brown. Red tide mostly occurs in coastal regions, and fertilizers play a large role in providing the nutrients needed by the dinoflagellates to bloom.

Another type of algae that tends to bloom and which many have heard of is blue-green algae. Blue-green algae is in fact not a type of algae at all, but rather a family of photosynthetic bacteria known as cyanobacteria. Different species of cyanobacteria can be found in either fresh or salt water. Like other forms of algae, cyanobacteria will often bloom in the right conditions, and most cyanobacteria tend to live on the surface of a body of water, where they can receive the most sunlight. Many species of cyanobacteria produce toxins that can affect the nervous, hepatic, and dermatologic systems. Some toxins can cause tumors or other health risks as well. Because many species can and do survive in fresh water, drinking water all over the world can be at further risk for contamination. Most species that produce toxins tend to produce multiple toxins, creating more complex problems.

Toxins produce by algae can devastate a local area. Many species of algae produce harmful toxins, and some species even produce multiple types of toxins. While it may seem like an obvious solution is to use pesticide on the algae, pesticides can have affect other organisms in an environment negatively as well. In addition, the toxins are not destroyed by pesticides. The situation can become worse if pesticides are used because the toxin is released into the water as the algae decompose, rather than remaining encapsulated in the algae as it would have been had the algae not died. In many cases, organisms that eat the algae aren’t affected by its toxin because the toxin is not in a high enough concentration to cause damage. However, the toxins tend become more concentrated the species that prey on the organisms that originally consumed the algae. As one moves up the food chain, the toxins accumulate, and problems arise as a result of the toxins. The highest level predators tend to be the ones with the most debilitating damage, and can even die from it. Even if they don’t die, the different toxins can have different effects, including brain damage and harm to pregnant organisms’ fetus, creating problems for future generations.

Humans aren’t completely removed from the harm done by toxic algae. Algal toxins can cause Amnesic Shellfish Poisoning (ASP). ASP is a condition in humans in which an algal toxin—namely, domoic acid—induces symptoms like vomiting, nausea, diarrhea, abdominal cramps, headache, dizziness, confusion, disorientation, loss of short-term memory, motor weakness, seizures, cardiac arrhythmias, coma, and can even cause death in high enough concentrations. ASP is so named because short-term memory loss tends to be one of the more common symptoms and the disease most often arises as a result of eating shellfish that had consumed toxic algae. Another disease caused by the eating of shellfish that had eaten toxic algae is paralytic shellfish poisoning (PSP). PSP is caused by saxitoxin, and symptoms can start as little as 30 minutes after consuming contaminated shellfish. At first, the symptoms are tingling of the lips, tongue, face, neck, fingertips and toes; followed by headache, dizziness and nausea. If the poisoning is severe enough, muscular and respiratory paralysis can take hold. Death occurs as a result of the respiratory system becoming sufficiently paralyzed, so that the victim can no longer breathe. As a result of the illnesses that are by algal toxins, the Department of Health Services requires shellfish growers in areas with a history of blooms to screen their harvests and test phytoplanton for levels of toxins. If the concentrations become too high, monitoring increases and admonitions against eating—and even quarantines on—the sea life in the area are set in place, cutting deeply into the pockets of fishermen who rely on the shellfish for their livelihoods. However, toxins are not the only problem caused by harmful algal blooms.

Deoxigenation of an area can also be a result of blooms. This issue seems somewhat counterintuitive; algae, much like any other photosynthetic organism, don’t use oxygen, but rather produce it as they harness the sun’s energy. However, the algae are only the indirect cause of hypoxic environments. When algae—or any other organism, for that matter—die, they become food for bacteria. As the bacteria decompose the algae, they also use oxygen in the water to help with their life processes. In ordinary circumstances, populations of bacteria are limited by the amount of dead organisms in their immediate environment, and the levels of oxygen in the water are more or less in balance. However, during an algal bloom, much more algae are present. When that algae dies, more food is available for local bacteria, and the bacteria population in that area rapidly increases. While the oxygen levels were balanced prior to the bloom, they can’t support the swiftly growing bacteria, and the amount of oxygen decreases. As a result, the concentration of oxygen eventually diminishes to a point at which fish and other organisms living in the water that rely on oxygen die off in the area. Fishermen can no longer effectively fish in that area even if the algae are not toxic, as the populations of fish are severely cut. If the hypoxic conditions are bad enough, they can often combine with toxicity to form a dead zone.

A dead zone is exactly what its ominous title suggests: an area in which almost nothing can survive. Dead zones are created when an algal bloom of epic enough proportions causes such severe toxic and hypoxic conditions and uses enough of the nutrients in the water in a habitat that the area can no longer support life and the ecosystem collapses. What’s more, dead zones are a growing problem. Dead zones affect an area 245,000 square kilometers. One of the best known dead zones is in the Gulf of Mexico, where the dead zone cycles every year. The cycle starts when algae begin to multiply. Eventually, they become a bloom. The algae die, harbingering the death of any other species that lived there. The dead zone grows, then begins to recede. Just as the area begins to recover, the process is started over again.

The Causes of Harmful Algal Blooms

Algal blooms are sometimes natural occurrences. Nutrients are naturally collected from the banks of rivers and washed downstream until they reach the mouth of the river. Then, the nutrients wash out into the ocean and support many coastal species. The algae—which may or may not be toxic—near the coast may bloom if the water conditions are ideal. That being said, extra nutrients—such as those found in fertilizers, detergents, and untreated sewage—are often introduced to rivers, causing larger, more frequent, and, overall, more damaging algal blooms. Fortunately, bans on phosphates in detergents are slowly spreading, and sewage treatment is a fairly common practice, but fertilizers are still a major problem.

Much like plants, algae tend to grow more with the addition of fertilizer, especially fertilizers containing ammonium nitrate and phosphates. Fertilizers tend to seep into the groundwater, which can seep into rivers and streams. The fertilizers eventually end up in lakes and oceans, significantly increasing the amount of nutrients available to species. When the fertilizers reach the algae, they rapidly grow and can eventually result in an algal bloom, potentially upsetting the ecosystems in which the algae had played an integral role in shaping and developing. While fertilizers may not have created much of a problem at their inception, fertilizer production and subsequent use has grown with to feed growing populations. In 1843, the commercial fertilizer industry was born with the development of a process to make superphosphate. In 1849, mixed fertilizers were starting to be sold commercially, and fertilizers became more readily available to the average American farmer. By the 1890s, the average fertilizer consumption per year was 1,845,900 tons. As fertilizers were refined and improved and more was learned about which nutrients were most important to which crops, the amount of fertilizer consumed by American farmers continued to increase, feeding the problem of harmful algal blooms. Over time, much of the world has adopted the use of fertilizers for their crops, making harmful algal bloom an even more insurmountable task.

Solutions

If fishermen—and aquatic environments at large—are to survive, something must be done to combat the unnaturally high frequency of blooms and their devastating effects. However, determining a solution to the problem of harmful algal blooms can be exceedingly difficult due to the environmentally sensitive nature of the problem. If all—or at least too much—of the algae in an area is killed off, then the food web of that area will be upset and many of the organisms that relied on algae either directly or indirectly will starve. In addition, many pesticides that could be used to kill the harmful algae in an area may also kill generally beneficial algae and other aquatic life, yielding no improvement over the dead zones that exist currently, and creating serious problems in areas where harmful algal blooms have not yet reached such a dire state. Even if a particular pesticide only killed one type of algae, as mentioned before, the toxins produced by and contained within some species of harmful algae would be released into the water as the dead algae decomposed, and the area of the algal bloom would remain reletively inhospitable to life.

If pesticides can’t be used beneficially, then what could be done to prevent the problem? Already some measures have been taken to prevent the key nutrients that lead to harmful algal blooms from flooding into the oceans. Many states and municipalities ban the use of phosphates in detergents. While bans on phosphates in soap helps, it does not completely eliminate the problem. In addition, many people oppose the bans because the detergents that are available to them which don’t contain phosphates don’t clean as well as the detergents with phosphates. Many people are so dissatisfied, that they find ways of circumventing the bans, such as going to neighboring states which still allow phosphates in their soaps. If bans on phosphates are to be successful, better detergents need to be developed that are of a similar—or even better—quality for cleaning.

In some situations, various chemicals are used to treat toxins that are released by algae. Chlorination, ozonation, and activated carbon have all been used to treat water sources to eliminate toxins produced by algae. Unfortunately, both the addition of chlorine and ozone to water, while moderately effective in destroying toxins, prove also to be moderately effective in destroying fish and other aquatic life if the levels of either chemical is too high. Activated carbon, on the other hand, is also used in filters for aquariums, and is much less likely to harm fish. Unfortunately, none of these methods are completely effective, and many toxins, such as microcystins produced by some species of cyanobacteria, are left unaffected. In addition, none of these methods are effective in preventing hypoxic conditions.

Because of the toxin release and oxygen depletion that results from algal death, it is far better to remove the algae from a harmful bloom before they die than to kill them. In order to remove algae, microfilters would be needed to sift through an area. At present, some technology exists to do this, but it is exceedingly expensive. Further research needs to be done in the area of microfilters to find a way to implement them more cheaply. The price would likely go down as more was discovered and better methods were put into place to make microfilters. Another unfortunate pitfall is that, due to the necessary fineness of the filter for catching algae and cyanobacteria, the filtration process in an area would take copious amounts of time and larger species may be harmed. To help cut down on time, several filters could be used in an area at once. As for the potential problem for larger species, the filters would need to be built so that organisms that could propel themselves could back out of the filter if needed.

Ideally, the concentrations of nutrients like nitrates and phosphates that flow into the ocean from farms and other human-based causes need to decrease to prevent the growth of algal blooms in the first place. It is, however, unrealistic to expect farmers to quit using fertilizers on their crops, as it would significantly decrease their profits and the amount of food available to the public. Instead, biofilters containing bacteria that utilize the nitrates in the water could be used. These filters could be installed as components to already existing dams. For rivers which are undammed or receive runoff from farms downstream of any dams, filters could be placed in different sections of the river. The housing for the filters would not span across the entire river, so fish would still be able to swim up and down stream. Because water would still be able to move downstream without going through the biofilters—either through fish ladders or in the area around the housing for the biofilters that weren’t in dams—so there would still be a high enough concentration of nutrients that the oceanic regions at the mouths of rivers would still be able to sustain life.

References

Spreading Dead Zones

Evolutionary history of Algae
A History of American Agriculture

Solutions to the Problem

2010-04-18T16:47:00.000-07:00

As illustrated in my previous blog posts, harmful algal blooms have been an increasing problem over time. Harmful blooms kill many marine organisms in an area, and even we humans are not safe from their effects. However, it can be difficult to determine a solution to such an environmentally sensitive issue such as this. If too much algae in an area is eliminated, then many of the organisms there will starve. In addition, many pesticides that could be used to kill the harmful algae in an area may also kill generally beneficial algae and other aquatic life, yielding no improvement over the dead zones that exist currently, let alone in areas where the algae problem has not yet reached such a dire state. Even if a particular pesticide only killed one type of algae, the toxins produced by and contained within some species of harmful algae would be released into the water as the dead algae decomposed, and the area of the algal bloom would remain inhospitable to life.

If pesticides can’t be used beneficially, then what could be done to prevent the problem? Already some measures have been taken to prevent the key nutrients that lead to harmful algal blooms from flooding into the oceans. Many states and municipalities ban the use of phosphates in detergents. While bans on phosphates in soap helps, it does not completely eliminate the problem. In addition, many people oppose the bans because detergents that don’t contain phosphates don’t clean as well as the detergents with phosphates. I even know several people in my own community who, dissatisfied with the quality of the locally sold detergents which are phosphate-free, go to a neighboring state that does not have the ban to get their detergents, making the ban somewhat ineffective. If bans on phosphates are to be successful, better detergents need to be developed that are of a similar—or even better—quality for cleaning.

At present, the addition of chemicals is used to treat areas that have already had blooms of toxic algae. Chlorination, ozonation, and the addition of activated carbon have all been used to treat water sources to eliminate toxins produced by algae. Unfortunately, both the addition of chlorine and ozone to water, while moderately effective in destroying toxins, prove also to be moderately effective in destroying fish and other aquatic life if the levels of either chemical is too high. Activated carbon has also been used to eliminate toxins in harmful algal blooms. Activated carbon is also used in filters for aquariums, and is much less likely to harm fish. Unfortunately, none of these methods are completely effective, and many toxins, such as microcystins produced by some species of cyanobactera, are left unaffected. In addition, they’re not as affective in combating the oxygen depletion that is caused by bacteria feeding on dead algae.

Because of the toxin release and oxygen depletion that results from algal death, it is far better to remove the algae from a harmful bloom before they die than to kill them. In order to remove algae, microfilters would be needed to sift through an area. At present, some technology exists to do this, but it is highly expensive. Further research needs to be done in the area of microfilters to find a way to implement them more cheaply. Like with most new forms of technology, the price would go down as more was discovered and the use of microfilters became more widespread. Another unfortunate pitfall is that, due to the necessary fineness of the filter for catching algae and cyanobacteria, the filtration process in an area would take copious amounts of time and larger species may be harmed. To help cut down on time, several filters could be used in an area at once. As for the potential problem for larger species, the filters would need to be built so that organisms that could propel themselves could back out of the filter if needed.

Ideally, the concentrations of nutrients like nitrates and phosphates that flow into the ocean from farms and other human-based causes need to decrease to prevent the growth of algal blooms in the first place. It is, however, unrealistic to expect farmers to quit using fertilizers on their crops, as it would significantly decrease their profits and the amount of food available to the public. Instead, biofilters containing bacteria that utilize the nitrates in the water could be used. These filters could be installed as components to already existing dams. For rivers which are undammed or receive runoff from farms downstream of any dams, filters could be placed in different sections of the river. The housing for the filters would not span across the entire river, so fish would still be able to swim up and down stream. Because water would still be able to move downstream without going through the biofilters—either through fish ladders or in the area around the housing for the biofilters that weren’t in dams—so there would still be a high enough concentration of nutrients that the oceanic regions at the mouths of rivers would still be able to sustain life.

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A Resource Guide for Algae

2010-04-08T22:23:00.000-07:00

I’ve provided a list of sites that seem to be good sources for more background and general information on algae and related issues.

http://www.hcs.ohio-state.edu/hcs300/algae.htm

This is a good site for a basic background of algae. It explains what they are, what distinguishes algae from plants, and a few other details.

http://tolweb.org/notes/?note_id=52

On this site, the evolution of algae is explained in some detail. In addition, different groups of algae are differentiated, and many of the groups have links to more information.

http://oceanservice.noaa.gov/topics/coasts/hab/

This site provides some good background information on harmful algal blooms.

http://www.cdc.gov/hab/

This is the CDC site on harmful algal blooms. As such, it’s a good resource for information on harmful algal blooms and has several links to more information from multiple sources.

http://www.bigelow.org/hab/

This site provides more information on harmful algal blooms with multiple links detailing location of blooms, types of algae that cause blooms, the effects on humans, and many other topics.

http://www.nature.com/news/2010/100111/full/news.2010.5.html

This is an article detailing a study that looked at why some algae produce toxins that, eventually, cause problems in ecosystems during algal blooms. It’s fascinating.

http://www.iode.org/haedat/

This is a database containing records of harmful algal blooms and other events. I only recommend it for those that are seriously interested in the subject, however, as a user account is required to access it, and the account can’t be obtained online.

http://www.sams.ac.uk/research/departments/microbial-molecular/mmb-project-themes/harmful-algal-blooms/researchproject.2007-05-01.4591446933

This article discusses one of the impacts of algal blooms on humans: poisoning from shellfish that have accumulated toxins from algae.

http://www.jstor.org/stable/3545761

In this study, the impacts of two major influence humans tend to introduce into aquatic environments—the addition of nutrients (such as through fertilizers) and the addition of herbivores—were observed as they related to algal species.

http://www.scitopics.com/Impacts_of_Climate_Change_on_Harmful_Algal_Blooms.html

This site provides some information on the impact of climate change on algal blooms.

http://www.howstuffworks.com/algae-biodiesel.htm

This is a site about detailing the way in which algae can be used to make biodiesel.

Videos:

http://www.scivee.tv/node/2749

This video gives a brief overview of the biology of algae.

http://www.kqed.org/quest/television/algae-power

This is a movie about algae’s potential as a source of power.

http://www.france24.com/en/20090811-faceoff-pollution-agriculture-health

This video is about the problem of algae rotting off the coast of France and debates the possible solutions to algal growth problems.

http://www.youtube.com/watch?v=a8ae2vq45eA&NR=1

This video discusses the phenomenon of dead zones. Specifically, it talks about the dead zone that is created every spring in the Gulf of Mexico.

Contamination of Drinking Water

2010-04-01T23:27:00.000-07:00

Recently in class, we discussed the privatization of water and the potential benefits and pitfalls of both municipal and private water sources. We learned that in many areas all over the world where poverty is rampant, the infrastructure necessary for the transportation and treatment of water is lacking or even nonexistent when under governmental control. As a result, the poor have to pay exorbitant amounts to buy their water and often have to spend copious amounts of time to transport it. In many cases, this highly expensive water can be unhygienic. Privatization can help alleviate the burden placed on local governments for the cost of infrastructure and allow the poor to receive water at greatly reduced rates. However, private companies can often skimp on the decontamination of water if the companies’ leaders become corrupt. The contamination of a water source—whether under governmental or private control—is a prime concern, especially when that source is used as drinking water. Many forms of algae, such as blue-green algae, can bloom in fresh water sources in the right conditions, and some species of blue-green algae are toxic.

Although there are many types of algae that inhabit fresh water, blue-green algae are some of the most ubiquitous. Unlike most algae, which are classified as protists, blue-green algae are actually a family of photosynthetic bacteria known as cyanobacteria. Different species of cyanobacteria can be found in either fresh or salt water. Many species of cyanobacteria produce toxins that can affect the nervous, hepatic, and dermatologic systems. Some toxins can cause tumors or other health risks as well. Most species that produce toxins tend to produce multiple toxins, making water treatment even more difficult.

Like other forms of algae, cyanobacteria will often bloom in the right conditions. Most cyanobacteria tend to live on the surface of a body of water, where they can receive the most sunlight. Any surface drinking water sources, such as lakes and reservoirs, are at risk for contamination as they provide the perfect habitat for cyanobacteria if not properly treated. Blue-green algae bloom when there is sufficient sunlight and nutrients in the water. Many human pollutants, such as fertilizer runoff and untreated sewage, can add nutrients to the water that can, in turn, creating a more hospitable environment for cyanobacteria to thrive in.

During a harmful bloom, the species of cyanobacteria that produce toxins rapidly becomes more concentrated. Once the cyanobacteria die, their cells lyse and the toxins are released into the water. As a result, the water source can remain contaminated until the toxins are able to completely decompose. In addition, any water treatments intended to kill the blue-green algae can make problems worse by inducing the release of the harmful toxins. While many treatments, such as chlorination, the addition of activated carbon, and ozonation, can be used to lower toxin levels, most treatments are less effective against certain toxins, such as microcystins.

Ideally, in order to reduce toxin levels, measures need to be taken to filter out cyanobacteria from water sources. However, the technology to do so is, as of yet, relatively undeveloped and extremely expensive. Some experimental treatments include ultraviolet light, titanium dioxide and filtration using ultrafine membranes. In addition, cyanobacteria tend not to inhabit groundwater, making that a safer source of drinking water than lakes. However, in both cases the cost to adapt infrastructure to combat the algal problems of an area would be high, and in many locations, local governments would not be able to afford it. Aside from the cost of infrastructure, groundwater—which may be a more feasible solution than specialized filtration systems at the present for most communities—can have other contamination issues when pollutants seep through the soil and is not always a viable option in areas where water is scarce and not enough seeps into the ground to create a large enough source to sustain a population. Privatization can help alleviate the burden of cost on municipalities and provide adequate decontamination of drinking water as the necessary technology advances and becomes more readily available; however, careful oversight must be maintained to prevent corruption and maintain water quality standards.

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For further reading:
http://www.rsmas.miami.edu/groups/niehs/science/bluegreen.htm

The Harmful Effects of Toxin-Producing Algae

2010-03-21T17:03:00.000-07:00

Although the increase in the rate of algal growth can clearly be seen, measured, and correlated to increases in the use of fertilizers (especially nitrogen-based fertilizers) in farming practices around the world, one might wonder how algal growth could have a negative effect. After all, algae are a naturally evolved and essential part of any fresh or salt water ecosystem. Algae convert the sun’s energy to sugars, and many fish and other organisms feed on algae to survive. The fish and other organisms then become prey to other animals, indirectly making algae an important source of energy for predators as well. One might even draw the conclusion that an increase in algae would induce an increase in the growth and populations of many other organisms as well.

However, the implications of rapid algal growth are much more complex that a simple increase in food. Algal blooms can create hypoxic conditions in marine ecosystems. This decrease in oxygen levels kills fish and other organisms that rely on higher concentrations of oxygen dissolved in the water. A potentially more devastating effect in higher algal populations is the increase in algae that produce harmful toxins. One such variety of algae comes from the genus Pseudo-nitzschia, which is one type of algae that blooms recurrently off the coast of California.

Pseudo-nitzschia produces the neurotoxin domoic acid. In humans, domoic acid induces vomiting, nausea, diarrhea, abdominal cramps, headache, dizziness, confusion, disorientation, loss of short-term memory, motor weakness, seizures, cardiac arrhythmias, coma, and can even cause death in high enough concentrations. Humans who suffer from domoic acid poisoning typically acquire the elevated levels of domoic acid from mussels and other shellfish that eat the Pseudo-nitzschia in their environment. Because of the tendency for short-term memory loss after eating the contaminated shellfish, domoic acid poisoning is also referred to as Amnesic Shellfish Poisoning (ASP). Because of the dangers of domoic acid and the recurring blooms of Pseudo-nitzschia off the coast of California, the Department of Health Services requires shellfish growers in areas with a history of blooms to screen their harvests and test phytoplanton for levels of the neurotoxin. If the concentrations become too high, monitoring increases and admonitions against eating—and even quarantines on—the sea life in the area are set in place. In the spring of 2007, California saw a dramatic increase in the concentrations of domoic acid off their coast.

While seriously affected, humans are not the only organisms affected by the neurotoxin. The fish and other organisms, such as shellfish, that eat Pseudo-nitzschia do not generally receive high enough concentrations of domoic acid to suffer observable negative consequences; however, the species that eat the fish and shellfish are frequently affected. Much like DDT becomes more likely to kill as it is consumed by higher-level predators, domoic acid accumulates in higher and higher concentrations as it moves up an ecosystem’s food web, affecting the topmost predators the most. For example, domoic acid affects the brains of birds—such as pelicans—that eat fish. As a result, the many of the birds start having seizures. When the seizures occur during flight, the birds can end up flying to unfamiliar areas, or simply falling out of the sky and even drowning. When sea lions eat fish containing domoic acid during pregnancy, the domoic acid tends to accumulate in the amniotic fluid. As a result, the fetuses’ brains develop differently and the offspring tend to have epileptic seizures and strange behavioral habits later in life.

While the algae are a naturally occurring organism in the aquatic environment, the high levels of fertilizers in the water have increase their populations, causing detrimental effects to the aquatic ecosystem and affecting all levels of the food web, including humans. If the growth is not curbed by decreasing the amount of fertilizer released into the ocean, the affects could even spread to future generations of both humans and aquatic species.

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References

http://www.cop.noaa.gov/stressors/extremeevents/hab/features/ca_pn_050807.html

http://www.sciencedaily.com/releases/2008/06/080609103232.htm

http://www.sciencedaily.com/releases/2007/04/070427084149.htm

http://www.freedrinkingwater.com/water_quality/quality2/j-11-08-algae-blooms-cause-severe-oxygen-depletion.htm

Test

2010-03-02T22:27:00.000-08:00

This is just to test a link.

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A History of Algae and Fertilizers

2010-02-24T21:52:00.000-08:00

Algae has had a long history, from when it was first evolving, then becoming an important part of the diet of fish and other aquatic organisms, to today.
The first photosynthetic life forms (from which algae would one day evolve) were cyanobacteria. In water conditions that provided little oxygen and high competition for accessible sources of usable energy, cyanobacteria were able to manufacture their own by using just the sun, water, and carbon dioxide—all of which was plentiful in their environment. Eventually, other bacteria evolved to the point that they could encapsulate a cyanobacterium and use it as an organelle. The energy-storing molecules that the cyanobacteria produced could be used by the larger cell, a relationship that would benefit both the host cell and its offspring. Over time, these specialized cells with energy producing organelles (known as chloroplasts) eventually evolved into algae.

Long after algae had begun its evolutionary path, humans began to endeavor into the agricultural world. At first, agricultural methods were crude and yields were minimal—at least by today’s standards. As time went on, practices were refined, and people learned better ways to gain more yield for lower costs in resources. Finally, in 1843, the commercial fertilizer industry was born with the development of a process to make superphosphate. In 1849, mixed fertilizers were starting to be sold commercially, and fertilizers became more readily available to the average American farmer. By the 1890s, the average fertilizer consumption per year was 1,845,900 tons. As fertilizers were refined and improved and more was learned about which nutrients were most important to which crops, the amount of fertilizer consumed by American farmers continued to increase.

Much like plants, algae tend to grow more with the addition of fertilizer, especially fertilizers with ammonium nitrate phosphates. While fertilizers may not have created much of a problem at the beginning of their use, the amount of fertilizer that was used increased steadily over the decades to feed both people and the economy. In addition, much of the world has adopted the use of fertilizers for their crops. Fertilizers tend to seep into the groundwater, which can lead into rivers and streams which lead to lakes and oceans. When the fertilizers reach the algae, they can cause rapid growth and even an algal bloom, potentially upsetting the ecosystems in which the algae had played an integral role in shaping and developing.

Evolutionary history of Algae
A History of American Agriculture

Increase in Algal Growth as a Result of Globalization

2010-02-15T21:34:00.000-08:00

Globalization is the spread of culture, economy, and religion into one large network that spans the entire planet. This spread can not only affect the people involved in trade and the global economy as a whole, but also the environment that we live in. As more countries become mechanized and move to a more westernized way of life, we are seeing more effects on the environment. Countries are increasingly effecting changes in agriculture and how people raise and handle their crops. There is an increase in the movement of non-native—and often invasive—species due to people. Most of all, we are seeing more use of agrichemicals such as ammonium nitrate in farming, as well as a higher dependency on fossil fuels and non renewable energy sources.

The Blog that I will be writing will detail how globalization effects the environment, specifically using algae as an example. I chose algae to be the focus of my blog because it sits at the bottom of the food chain, and while it may be small and seemingly unimportant, it can have a large effect on the entire environmental processes that take place above it. Algae can be affected by many things from temperature, chemical, and other changes that take place in its environment. Algae can give us a good view of what is happening in an ecosystem. It can also help us to understand how the planet as a whole is being affected because it occupies a large portion of our oceans, lakes, and other waterways.

The increase in the use of fertilizers in different countries all over the world has had a significant impact on the growth of algae. As excess fertilizer is washed into streams, it is taken down rivers into lakes and oceans. The algae that grow these areas are then exposed to the fertilizers and other chemicals, which provide the algae a more hospitable environment in which to grow and multiply, sometimes even causing algal blooms and dead zones.

Algae is a highly important part of aquatic ecosystems, providing food for many herbivorous creatures; however, too much algae in an area can disrupt the balance of a food web, ultimately resulting in the decrease in population of many species of plants and animals and—in extreme cases—dead zones. This decrease can have a harsh impact on the lives of peoples who rely on the benefits of oceans and lakes to survive and make an income. For example, fishermen can often be impacted if algal growth causes the decrease in the populations that they fish. Although they may still be able to catch some fish if the area is not rendered into a dead zone, the added competition of a global market can make it more difficult to profit from a smaller number of fish.

Although the most obvious solution to the problem of algal growth is to decrease or cease the use of chemical fertilizers, the problem is not that simple. If chemical fertilizers are banned or limits are placed on their use, farmers will get lower yields. The banning of fertilizer would therefore merely shift the hardship from fishermen to farmers, rather than eliminating it.

Spreading Dead Zones