PDS AP Environmental Science 5th Period 2011-12

After testing a handful of vehicles in each class, we tried to analyze the class data for trends. It has become harder and harder to do as vehicle emissions have become so much “cleaner” over the last decade (yes, I said it). If we had the time, this is the data I would love to gather:

Relationship between CO2, CO, HC (Click to enlarge)

One reason vehicles emissions have improved so greatly in the USA, is catalytic converter technology. Catalytic converters speed reactions to reduce the amount of NOx, CO, and HC coming out of an automobile. Check out how catalytic converters work at howstuffworks.com.

Catalytic converters are pollution solutions!

Why does all this matter? Well, NOx have a key role in the formation of ground-level (tropospheric) ozone and photochemical smog. Reduce NOx (and CO and HC), and you reduce ground-level ozone and photochemical smog. You need to be familiar with both types of smog (below) on the AP exam.

Smog Types

I am still a little confused about fuel rods and control rods with regard to nuclear energy. I understand that control rods can be inserted to take up electrons or taken out to leave the electrons in (increase or decrease fission). So, basically, they control the amount of energy and electricity generated. But I get confused about what the fuel rods are. The book definition says that they are “cylindrical tubes that enclose the nuclear fuel within a nuclear reactor.” Does that mean that the reaction takes place inside the fuel rods? And that the control rods are inserted into the fuel rods to slow the reaction if needed? I guess I am just having a hard time picturing this and if someone could clear it up that would be great.

Just to clarify, is fission when a nucleus splits and fusion when nuclei combine? And does fission just produce heat while fusion produces energy? I would love it if someone could help me understand the distinction between the two!

I know that nitrogen and phosphorous can cause algal blooms which ultimately decrease the amount of oxygen in the water, but don’t you want some nitrogen and phosphrous so that underwater vegetation survives? And I’m confused about how much nitrogen and phosphorous cause algal blooms. Could someone please clarify this for me?

I was just reviewing all of the steps for cleaning drinking water and there was one aspect that I am a little confused about. I don’t quite understand exactly what flocculation is. I know that it has something to do with coagulation which is when things are clumped together. But I just need some clarification on what that step of the process means and what it does.

Alrighty, so I know that meat production can be split up into CAFOs and free range, however, I noticed that there is also traditional agriculture mentioned in the book. Traditional agriculture can be classified as shifting agriculture or nomadic grazing. I was wondering if any, which category traditional agriculture would fit in. It seems that it would lean towards the Free Range category, but I was wondering if maybe it’s actually just it’s own category all together. It seems like these systems wouldn’t be used for mass production but rather the family farm or maybe a small town. What do you guys think?

I was just looking at the pros and cons of aquacultures and I was a little confused about what the positives were. The only thing that I could find is that it alleviates human caused pressure on overexploiting resources. I’m not really sure what that means or why that is different then fisheries. And I also don’t know any other positives than that and I was wondering if anyone had found more.

So in class today, we discussed e-waste, which is essentially the disposal of computers, televisions, phones, and other electronics. We then discussed the harmful consequences involved in the process, especially when it’s exported to foreign countries like India and China. However, we never really got to talking about a good way to get rid of the waste. My question to all of you is, “What’s an effective and responsible way to dispose of e-waste?”

I know that we briefly described this in class today, but I am still a little confused on quantitative risk assessment. I understand that qualitative is when a person makes judgements on how hazardous substances are based on perceptions that really have no scientific data to back them up. But for quantitative, I have that the risk is measured by the probability of a person being exposed to the hazard divided by the probability of being harmed if exposed. Is that considered scientific data? So does that mean that quantitative assessment is based on only scientific fact rather than perception? I just need this to be clarified.

In my notes I had written maximum sustainable growth is 1/2 of the carrying capacity, and I was a bit fuzzy on what that really meant. I looked it up in my text and it basically said that the amount that can be harvested in order to not harm the environment is half of what the area can hold (the carrying capacity). Wouldn’t this idea completely contradict the idea of clear cutting? Or does it not pertain because areas that are used for clear cutting aren’t meant to be sustained..In other words, does maximum sustainable growth not matter for areas that are used for clear cutting and economic profit? Where does MSY apply? Only in areas that are moderately restricted? Also, how does it affect biodiversity of an area?