PDS APES 8th Period 2009-10

Okay…So our book says that 80-90% of the world’s hazardous wastes is produced by developed nations, with the United States leading the way.  However, to me it seems like nations such as China that are in the process of inten industrialization would be producing much more hazardous waste or waste in general than an already “established” nation such as the United States.  I guess I can understand why the U.S. produces about 1/3 of the world’s solid waste because we are a nation of excessive consumption, but it seems to me that developing nations should be contributing a little more to the total hazardous waste count?!  Also, I’m just curious to know if as a class, y’all leaned more towards “pro” recycling or “con” recycling…And then as a nation, does the U.S. lean towards one direction rather than the other, as well?

While water shortages are a major concern for people around the world, some regions of the world also face major problems dealing with WATER SURPLUSES: natural flooding caused by excess rainfall or melting snow.

So what is a  flood? — A flood occurs when water of a stream, river, or other body of water rises, overflows, and spills onto the surrounding floodplain (flat valley floor net to a stream channel; provide natrual flood and erosion control, maintain good water quality, and recharge groundwater — definition from Miller textbook).

Floods have two principle causes:

1. Natural Causes (rain, melting snow, etc.)

2. Human Activities (construction of dams, levees, floodwalls, etc.) which make the situations worse!

So why would anyone want to live or build on a floodplain? 1. Fertile soil, 2. Easy access to water for irrigaition, 3. Nearby rivers = transporation & recreation.  In an effort to reduce the threat of flooding, humans narrow and “channelize” (straightened) rivers, construct levees and floodwalls, and damn rivers in order to store water in resorvoirs and control its release.

While these protective efforts by humans may control the immediate threat of flooding, they may actually increase potential flood damage.  For example, during the “100 Year” Flood Event of 1993 in Mississippi, human activities actually caused the flooding to overwhelm surrounding regions of the Mississippi River and escalated the flood’s damage:

Other human activites that have contributed to flooding include:

• Channelization – reduces upstream flooding BUT destroys habitats and encourages human settlement, which then increases the risk of damages and death from floods.
• Construction of floodwalls — pavement creates an impermeable surface, therefore, less water infiltrates into the ground and more water remains on the surface headed to the river; this creates higher flodostage rivers.
• Removal of water-absorbing vegetation (especially along hillsides) — Replace with farm fields, pastures, pavement*, and buildings that do not exhibit the same water absorption! (See page 244 for a good diagram in the textbook)
• Draining wetlands which help control flooding and then building on them.  For example, Hurricane Katrina was a devestating tropical storm that hit New Orleans and the Gulf Coast in 2005.  However, we should have been more aware of the potential destruction because New Orleans sits BELOW a major lake (Lake Pontchartrain) and BESIDE a major river (Mississippi River).  The city has also sunk 10 feet below sea level because of the city’s mass and water usage with few surrounding marshes to alleviate the pressure.
• Construction of levees — For example, the 1973 flood in the Mississippi Valley caused an immense amount of damage and proved that so-called improvements such as levees and “cut-offs” to help control the river’s waters was not effective and actually increased the damage.  The levee’s actually trapped water and allowed it to build mass, speed, and force = DANGER! which caused much destruction!

Mississippi River Levee:

The Three Gorges Dame in China (World’s Largest Dam)

Click on this link for some footage of the destruction caused by Hurricane Katrina and some conversations between New Orlean ocals and news anchor Katie Couric:  Images of Hurricane Katrina\’s Destruction

So what can we do to help?  What’s the best solution?

In the past, we have relied heavily on engineering devices such as dams, levees, floodwalls, channelization, etc. to control flooding, but these methods have not proven to be effective since we have experienced several disasters because of them.  The best solution for us currently is to rely more on nature’s systems that are already in place and focus on prevention:  We can preserve forests close to watersheds, preserve wetlands in floodplains, and use floodplains wisely (recharging aquifers and sustainable agriculture).

Sources:

Miller, G. Tyler and Spoolman, Scott.  Environmental Science. Chapter 11

http://dsc.discovery.com/news/2007/06/22/gallery/dam3_zoom.jpg

http://www.travelchinabooking.com/images/china-pictures/three-gorge-dam-01.jpg

http://web.mst.edu/~rogersda/levees/Mississippi%20Levee%20during%201973%20flood.jpg

http://earthobservatory.nasa.gov/Features/HighWater/Images/mississippi_tm5_91_93_542.jpg

Hey, Guys!!!  I hope everyone’s studying is going well!! 

Okay…So I understand that an oligotrophic (poorly nourished) lake is a newly formed lake, usually formed by glaciers and mountain streams.  A eutrophic (well-nourished) lake is an old lake that is typically shallow with murky brown or green water.  That I get. 

I get confused when it comes to their NET PRIMARY PRODUCTIVITY levels.  On page 101, there are two side-by-side pictures of lakes.  Our book says that oligotrophic lakes have low NPP while eutrophic lakes have high NPP, but doesn’t NPP have to deal with producers’ access to sunlight.  If producers contribute the most to ecosystems’ NPP, then how can a lake covered in murk have a high NPP?  Isn’t the sun blocked from reaching the lakes’ bottom?  So, is cultural eutrophication a good or a bad thing? I guess it might depend on the situation and to what extent human inputs of nutrients modify the natural ecosystem.

Hey, Guys….I know this is a late post, but I was just wondering if anyone could help clarrify what exactly a pension is, and how pensions are used to either stimulate or inhibit population growth in countries.  My understanding is that as the “baby boomers” age and approach retirement, there will be higher pensions and a greater need for social security.  BUT…the problem is that there will be less working young-adults to fund these expenses?!….

Hey Y’all!  So I was reviewing Chapter 6 and came across a section I don’t remember discussing in class (pg.107).  Our book discusses three different aspects of stability or sustainability (inertia, constancy, and resilience).  I’m just having a little bit of difficulty distinquishing between the three, mainly the difference between inetia and resilience.  From what I understand, inertia is kind of like the “before” — resist being disturbed — and resilience is kind of like the “after” — repairing damages after a disturbance.  Does this sound right?! Thanks, guys!  –Molly =)

Hey, Guys!

Sorry if y’all answered this question in class today, but I was having trouble differentiating between rocky and sandy beaches.  My understanding is that they are both located in the intertidal zone, and that species in both areas must adapt to fluctuating water levels, salinity levels, and temperatures.  There does not seem to be a striking difference between the two besides the obvious fact that one is rocky and one is sandy?!?  Did y’all go into greater depth in regards to the differences between these two zones in class today?

Thanks!  -Molly (P.S. Sorry this post is so late!  I just got back from a visit at Emory)

First of all, I apologize this post is so late!  I totally understand if no one responds!  Okay…I understand the different “forms” solar energy reaches the earth (electromagnetic waves–UV radiation, visible light, and heat or infrared radiation).  I also understand that 95% of the harmful radiation from the sun is absorbed by the ozone layer.  I am confused when our book states, “Of the total solar radiation intercepted by the earth, about 1% reaches the earth’s surface.”  It seems like there is a 4% missing; I know it hasn’t gone “missing,” but where has this 4% of solar energy gone!?  Does this 4% simply exist as light/heat in our atmosphere and never specifically reaches the earth’s surface by directly touching/making contact with land?  I’m probably way over thinking all of the %, but if someone could correct me that would be awesome! Thanks, guys! Good luck with your studying tonight! =)

Determining Your Ecological Footprint:

an ecological footprint

To begin our discussion about ecological footprints, each student was asked to visit a website–http://www.ecofoot.org/–and use the Ecological Footprint Calculator to estimate his/her ecological footprint.  After each student emailed his/her results, Mr. Willard was then able to compile the results and determine an average for our class ecological footprint.

In our textbook, per capita ecological footprint is defined as the amount of biologically productive land and water needed to supply an individual with renewable resources and to absorb and recycle the wastes and pollution produced by resource use.  It is an estimate of an individual’s consumption of earth’s resources.  This definition is important to understand; one’s ecological footprint includes the impact of the food, shelter, mobility, goods, and services in our lives.

Currently, the equation I = PAT can be used to estimate a nation’s ecological footprint (I = impact, P = population, A = affluence, and T = technology).  As Kyle kindly pointed out during our discussion, this equation is ridiculously oversimplified!  But it can be used to help us roughly approximate a nation’s impact on the environment:

China’s Impact = (1.3 billion people) (affluence of 2) (technology level of 8 ) = 24.

United States’ Impact = (.3 billion people) (affluence of 5) (technology level of 4) = 6.

Kyle argued that affluence did not necessarily correspond directly with a nation’s environmental impact.  In other words, the United States is a very wealthy nation but our affluence does not necessarily mean that we have a greater environmental impact.  Or does it?  The United States makes up only 5% of the world’s population, but we are responsible for 25% of the world’s pollution!

During our class discussion, several arguments were made regarding this issue.  Does affluence = bigger ecological footprint?  Overall, we concluded that “it’s all about trade-offs.”  Some folks are wiser and use their money to invest in compact fluorescent light bulbs which are more energy friendly while some less economical folks spend their money on luxurious vacations! =)

So when should we feel guilty about our ecological footprint?  After completing the activity on the Global Footprint Network site, my own ecological footprint was calculated to be this:  if everyone in the world lived as I do, it would take 6.8 planets and 30.2 acres of land to sustain the world’s population.  Yikes?!  We only have 1 planet to sustain the world, and if there were 6.8 billion of me, we would need 6.8 planets!  Well, this is precisely why studying environmental science is so important; we must work to find solutions!

Right now, the world’s population is following a constant, exponential growth rate (a J-curve).  But what is the earth’s carrying capacity?  As our population continues to grow, the earth’s carrying capacity cannot grow along with it.  There is a limited amount of materials and resources; the only resource we can “import” is solar energy, and even a great amount of this energy source is lost through radiation, etc.  Unfortunately, as our affluence increases, the carrying capacity of the earth will decrease as more and more people will be able to live “less simple” more extravagant lifestyles.  More people will be able to afford to “overindulge,” “over consume,” and “over use,” the earth’s resources.

The trick is finding an appropriate balance!  The world is constantly changing and nations are always transitioning.  Until the 1970s, the United States neglected the rise of industry’s impact on the environment.  So as other nations of the world develop, do they have the same right to industrialize even if it has a negative impact on the environment?  Or is it our duty to stop these nations from making the same mistakes as us?

Thanks for an interesting class discussion!  I hope this post helps us keep all of today’s arguments and information organized!

Here are some additional articles to check out regarding ecological footprints:

“Carbon Footprint of Best Conserving Americans is Still Double Global Average” http://www.sciencedaily.com/releases/2008/04/080428120658.htm

“Calculator of Carbon Footprint for Nations” http://www.carbonfootprintofnations.com/content/calculator/82/

“Ecological Footprint” http://en.wikipedia.org/wiki/Ecological_footprint

Molly Snyder =)

Hey Guys!

I was looking over my chapter 1 study guide, and was confused about question #4.  What exactly does it mean to live off of “principal” or to live off of “interest.”  These terms sound like  they apply to business or to the economy, and I am having trouble relating them to the environment.  Does living off of “principal” mean that you spend money or  use resources carelessly without “investing” anything for later generations to use?  And does living off of “interest” mean that you save/preserve valuable resources for later use?  If you live off of “interest,” do resources actually increase in value?  Do you earn “environmental interest?”  If someone could just clarify this point for me that would be great!

Thanks,  Molly =)