Monday, November 7, 2016

Dead Zones


The world’s oceans are experiencing a phenomenon currently referred to as dead zones.  A dead zone can sometimes occur naturally in the ocean. But due to nutrient pollution resulting from human activities they are popping up more and growing faster than ever seen before.   Dead zones are areas of water that do not have enough oxygen to support a living organism.  They can also be found in lakes, or any other body of water.  Generally we see dead zones along costal communities or cities. As stated before dead zones are caused by nutrient pollution.  These are pollutants that are entering our water because of some form of human process.  Generally we are talking about fertilizers from farming, sewage, etc.  Much like the plants on dry land, microscopic plants in the water called phytoplankton benefit from these extra nutrients added into the water.  This causes phytoplankton populations to explode in that area of water, which has an array of negative effects.  These phytoplankton than die and sink to the bottom which is a problem when concerning dissolved oxygen. 
Underwater cameras mounted to remote control robots have scanned the sea floor in these areas and came back with quiet frightening images.  We see dead crabs, fish, coral, and other organisms all along the bottom of the sea floor.  Some organisms like larger fish will move out of the area before the dissolved oxygen content gets to low to survive.  Other organisms like coral, sea slugs, starfish, etc. that either do not move fast or at all are often trapped, and die.   The biggest contributor that we are able to identify at the moment is agricultural run off.  Because most countries have some form of agriculture, we see this worldwide.  And it’s not just the dead zones being affected.  The worlds leading oceanographers are now saying that the dissolved oxygen content is actually going down in the ocean as a whole.  This is a very threatening issue to humans’ wellbeing all over the globe.  The effects of this are truly endless, it can change ocean currents, weather, fish population, and just about anything else relating to the ocean.  We as a species have been extremely negligent in caring for the ocean.  Just recently we pronounced the Great Barrier Reef dead.  And we are making no significant gain in the right direction.  We are increasing environmental regulations here in the US but many say it is just to late.  Also it is hard to take a step in the right direction as a whole when so many underdeveloped countries are functioning just as if there is not a problem.  Fact of the matter is it is expensive to be environmentally responsible, so how do we as a planet get everyone to care more?  That is the question that scientist and world leaders alike are currently trying to figure out.  But with the worlds population growing as it is, we need to increase food production constantly.  This means more farmland, more fertilizers, and more runoff getting to our oceans. 

Sunday, October 30, 2016

Impact of Dams


Dams, and more specifically hydroelectric power, provide the modern day world with a large portion of our electricity.  So how do these dams generate such an immense amount of power?  A river is blocked off first, to allow the construction process to take place.  Than a large concrete barricade is erected, and fitted with turbines and a path for the water to contact them.  The difference in water level pushes water through channels in the dams.  This water rushes past turbines spinning them.  The turbine in the generator is connected to a shaft, which suspends large electromagnets.  The spinning of these magnets at high speeds generates a flow of electrons, also known as electricity.  Some countries like Canada and Australia, have an extremely significant amount of their power generated this way.  The largest dam in the world is the ThreeGorges Dam in China. 
Dams have little to no air pollutants generated.  In fact, dams generate almost no waste products at all.  So why are we not building dams on every waterway?  Well actually in the United States we are doing quiet the opposite.  We are actually taking down a lot of dams.  This is for an array of reasons, but the biggest being environmental impact, which at first glance seems very low.  But there are to many negative impacts to count in some ways.  The first being displacement.  Building a dam raises the water up stream, often creating lakes.  All to often, this makes thousands of people relocate, especially in countries like China, were the government seems all too willing to relocate citizens.  Disrupting the natural path of water seems to have a large impact on wildlife.  Fish that have a natural migration pater up these waterways like salmon, can no longer make this journey.  And because they are usually headed up stream to bread, this means a severe decrease in population.  Slowing water flow also makes water more stagnant upstream, which makes the dissolved oxygen content go down.  This also usually means fish found upstream from a dam have increased parasites, and are more susceptible to infection.  Down stream we see these effects for a different reason.  As the water goes through the dam it usually heats up.  This is either because it runs in a shallow stream down a shoot, or because the water is used to cool moving parts, in turn heating it up.  So downstream from the dam we see increased water temperature.  This encourages bacteria and algae growth, which means lower dissolved oxygen.  Also warmer water is not as capable of holding dissolved oxygen.  This really hurts the ecosystem, because the wildlife in rivers are usually very delicate.  So all this makes us ask ourselves are dams worth it.  On one side, fewer dams means more energy generated from fossil fuels, which harm the environment too.  But on the flip side, dams harm the environment in other ways, and require a lot of resources to build.  In conclusion, we need to access the impact for that specific area to really decide if it is worth it.

Wednesday, October 19, 2016

Aquaculture


Aquaculture is a fairly new process in the modern world.  When we describe aquaculture we are usually talking about the farming of fish, but it can involve aquatic plants, oysters, clams and even crayfish.  Aquaculture is seeing a lot of growth across the word just recently.  With the worlds ever growing population and seemly exponentially growing need for meat, we are looking to aquaculture for answers.  Fish are one of the most efficient animals to raise.  They require much less resources than cows, pigs, or most other sources of meat.  Currently a great portion of our fish is coming from the natural environment.  And there is a sustainable way to harvest fish.  However we have done a great amount of damage due to overfishing.  These are the reasons aquaculture is exploding.  The process of aquaculture is really quiet simple.  There are a variety of ways to grow fish in particular.  The simplest way is simply in an outdoor pound.  This also happens to be the most environmentally friendly way.  Although you may not have as much yields as you would other methods.  The downside to this is that you do not have complete control over the environment, and fluctuating temperatures can be a danger.  Also outdoor predators and parasites can effect fish population.  The second method and the one most growing in popularity is the indoor tank method.  This method consists of large indoor tanks, but takes up much less space than a pound.  You can also grow the fish in much higher densities.  You have control over water temperature, food distribution, etc.  These systems are expensive to build and require a relatively high amount of energy to run.  However they can be built virtually anywhere, and because they are usually indoors climate is not as much of a factor.  Also you can use bio-filters to convert fish waste to nitrates.  This can than be used to grow plants.
  The third main way to do aquaculture is to have a netted or caged area in a large body of water.  This can means a pound or even the ocean.  New Zealand is a country that is currently exploring the netted method.  You can raise a variety of species in the ocean, in a habitat similar to what they would be in in the wild.  Food has to be supplied but water temperature and other factors are natural.  This is a relatively low cost method in smaller scales and if closer to shore were it is easily reached.  The downside to this is the ocean can have violent whether.  Your enclosure has to be able to sustain harsh conditions it may be exposed to.  Existing floating fish farms have also experienced some problems with predators of the ocean.  This method can put the fish in the way of sharks, birds, and in some cases, humans.  People have been caught fishing in these floating cages and arrested.  With muscles and other similar animals, they are often grown on grates or screens.  Because the animals are filter feeders, they do not cost anything to feed.  This is a relatively environmentally friendly operation because muscles actually filter the water and the operation produces little waste.  The downside is they take a long time to grow and produce relatively low yields.  Overall aquaculture is an expanding field and will be growing in popularity as it becomes more efficient.  

Tuesday, October 18, 2016

Contaminated water

The water we use everyday has the potential to carry a lot of things we may not notice.  Contaminated water can carry heavy metals, chemicals, and more things that can harm us.  One of those things that we don’t think about too much in our everyday lives is waterborne disease.  Waterborne diseases can come from a huge variety of sources.  Some of the most common like cholera can often come from sewage entering our drinking water.  This can happen in water treatment plants when they fail to fully decontaminate their water.  It can also happen in  when the water is in transportation if some contaminate becomes entrained in a pipe carrying clean water.  It can also happen in ground wells.  This means some form of sewage, or waste has seeped through the ground and contaminated a well from which someone is pulling water.  While wells are sometimes contaminated in the United States, this is usually something more common in third world countries.  This is usually due to lack of infrastructure.  Treatment of waste is something that often plagues these undeveloped countries.  For the same reason, this waste is sometimes actually discharged into water sources like rivers.  Certain climates actually allow the bacteria or microorganism to reproduce in the water.  This is something we in Ohio saw this summer in Lake Erie.   Heavy rains this summer surpassed our infrastructure’s capacity to carry water.  This resulted in a large amount of sewage/septic water entering Lake Erie.  This combined with high summer temperatures created a perfect breading ground for bacteria.   In 1993, an outbreak of intestinal disorders and diarrhea occurred in Milwaukee and labs discovered the presence of cryptosporidium in the water system throughout the area. The protozoa infected about 400,000 people and it caused the most serious waterborne disease outbreak in the United States. Cryptosporidium cysts are difficult to detect, even in a well-equipped lab.  And in 1993 we did not have all the equipment we have today.  So this was a fairly difficult problem to solve.  The cyst formed by the protozoa is also difficult to kill because they encapsulate themselves in a durable coating. 
It was recommended residents boil their water for an extended period of time or use bottled water. Dysentery is also a harmful condition that has affected the U.S. in the past.  It is actually caused by two different organisms.  One of these is an ameba and the other is a shigella.  A person can have symptoms of Dysentery after ingesting as few as 10 of these organisms.  It is a very tricky thing to rid the water system of it once it is entrained because it is resistant to many water treatment methods.  Since sanitary conditions in the United States have improved greatly this is something we don’t see as much of anymore.  However, human waste (that has been treated) is occasionally spread on fields in some states as fertilizers.  It is obviously impossible to kill every organism in that mixture.  And occasionally a few cases will pop up in the area due to a heavy rain resulting in contamination.



Tuesday, October 11, 2016

Water Wars


We in this part of the country (Ohio) tend to take plentiful clean water for granted.  But in 2016, that cannot be said for the whole country anymore.   California is in the middle of one of its biggest modern day droughts ever.  It is currently getting water from other parts of the United States because water is so scarce there.  People are discouraged to water their grass or even wash their cars.  
But this is not just a problem in California.  In fact it is a growing problem all over the world.  This is largely because of the growing population in the world, especially in third world countries.  Have you ever thought about how much water you really use a day?  You may say the water you drink and use to shower etc.  But there is a plethora of factors you don’t think about normally.  What about your food?  How much water does it take to raise a cow, or grow the fruits and vegetables you eat.  The numbers would probably shock you.  So you see a person uses much more water than you think.  So when you are adding thousands of people to certain parts of the world annually it can be a big problem.  The Middle East is the current hot bed for such conflicts or “Water Wars”.  And many people speculate that water will be the topic surrounding the next big war.  And that may sound surprising at first, but not so much when you think about it.  You can only survive about 3 days without water.  So you can bet that people will do extremely drastic things to get it.  Add a drought into the mix, and one country controlling the flow of a river to another, and you have recipe for conflict.  And it is exactly that, that is happening now in the Middle East.  Major dams on the Tigris and the Euphrates are now seen as weapons of war.  As Islamic states like Iraq and Syria scramble for the liquid gold that is water.  Old treaties are being re-evaluated due to new conditions.  Who get to uses the water for what is up for dispute.   Currently (Sept 2016) the tensions are growing with every passing day between many countries in the Middle East.  The UN is trying to intervene but is worried that this may be a conflict that is resolved in war.  It is situations like this that make us realize how crucial water really is.  Without water we can do virtually nothing, and that includes simply living.  Not only is it our responsibility to conserve water, but also to keep it clean, so we can re-use it.  It is not out of this world to think that someday the United States will have to deal with an issue like this.  The weather has shown us how quickly climate and water supply can change, and at alarming magnitudes like in California.  Knowing this, it would be wise to conserve as much water as we can now, and figure out new ways to keep it a clean and renewable resource, for everyone to use.