I’m still a bit confused about the notion of retention of water as a function of infiltration. In our background reading for the lab, it says that clay has low infiltration, which would mean that there would be high runoff. However, I’m confused because I thought that clay had high infiltration because it holds the most water (therefore my thinking was that there would be very little runoff). And similarly, it says that sand has high infiltration. But how can sand have the least runoff if it is also the most permeable and lends itself to the most leaching? Could someone please help me with this concept?
This might not show up on the exam in May but I’m wondering if there are similar animal right’s concerns involving the fish CAFO that were present in the livestock CAFOs. The movie we watched didn’t really touch on it much. The fish seemed to have a lot more room to operate and they seemed to be overall happier I’m just wondering if this is as great of a concern for fish CAFOs.
Does anyone know what US legislation/agencies we need to know? Also, on the study guide Mr. Willard mentions something about the efficiency of feed to meat conversion, can anyone explain what the answer might be to that?
Kinda weird to discuss fishing/aquaculture in an agriculture unit? Well, we do get some calories from the water so yes! Today we watched a good bit of the PBS documentary Empty Oceans, Empty Nets. Feel free to click around the movie web site if you want want to explore the issues further. What were the main points?
1. The Problem. Yes, we seem to be overfishing the oceans. In the last 4 years, numerous articles have come out predicting the collapse of most commercial fisheries by 2050. If you have 5 minutes, read this very current article cleverly titled, “Aquacalypse Now: The End of Fish.” This brief public service announcement give some reasons WHY this is happening and what we might do about it.
2. Causes. As mentioned in the PSA above, many of the “industrial” fishing methods used by large vessels or factory ships have the potential to remove fish from our oceans in massive quantities. Check out the animations at this Monterery Bay Aquarium web site of bottom-trawling, longlining, and purse-seine fishing techniques. Additionally, each of these method capture different types of bycatch (bykill). The movie we watched stated that for every pound of shrimp caught in the US fisheries, there may be five pounds of bycatch! Sometimes, it may include endangered animals like sea turtles.
3. Solutions: We saw several solutions throughout the film-we just did not get to discuss them today.
Since this is a commons issue (oceans fisheries), governments can regulate fisheries by setting quotas in their territorial waters. Anything involving species migrating across oceans and/or beyond those 200 miles offshore has to be addressed by international treaty, but enforcement becomes problematic.
Governments can establish marine protected areas (MPAs), marine reserves, or marine sanctuaries in their territorial waters. Check this link for the US system of MPAs. These are safe areas for fish to hide and breed as fishing there is usually banned. Remember, government regulation is ONE solution to The Tragedy of the Commons…
Consumers can create more demand for fish taken from sustainable fisheries. If you care about making a personal impact by your seafood choices then you can download a pocket guide from this web site. There is also an app for mobile phones/ iPhones at that link.
Hey, I took over some scribe duties since it was so close to the test. While King Corn focused on industrialized corn crop production and the many issues it produces, the movie also touches on problems created when we feed all that corn to cows (who did not evolved to eat it) in industrial feedlots or factory farms or CAFOs. If you were out, here is a brief lesson..
First, watch this short, hilarious clip called “The Meatrix” that raises some of the issues created by feedlots:
*Trouble viewing video clip here, try this link-you can even find sequels!
Second, here is a good summary post by former APE Kevin Chu (’10):
“We are what we eat. For Americans that means we eat a lot of processed foods. When you pick up a bag of potato chips, its easy to see that the product is unnatural, the chip didn’t fry itself and dip it in oil man did that. But what about the meat we eat? In class today we talked about how the meat production industry has changed since the early 1980′s, about the mechanism that replaced the stereotypical small farmer, CAFO’s.
CAFO’s, or Condensed Agriculture Feed Operations (a.k.a. feedlots)is brain child of antibiotics and genetically modified corn. GM corn allows for cheap feed for cows, while antibiotics allows for livestock to bypass population density inhibitors along with an increased growth rate. What this means is that we can now feed more cows, aka produce more meet in less room. That may sound like a simple achievement, but these adjustments allowed for a much higher rate of meat production than other farming methods by fencing animals as tightly as possible, and fattening them as fast as possible.
Just because the CAFO business is booming doesn’t mean that grass fed cattle operations don’t exist. There are still farmers who feed livestock on open pastures or fenced ranged land. But compared to CAFO, the output is so low, increasing pricing that grass fed operations only operate a small consumer niche of the market. Although economic incentives are virtually nonexistent in this market, there are ecological and personal incentives to eat grass fed.
As mentioned in King Corn, the ratio of saturated fat per t-bone in grass fed to corn fed is 1.5 to 9, which helps explain rising obesity rates. This along with the fact that cows aren’t meant to eat corn brings up some potential health issues. Other than health issues, by using feedlots, though we are conserving biodiversity by using less land, we promote other environmental issues. With high production of meat comes high production of manure, and methane(global warming gas). Although manure could be a plus since it could be used for fertilizer, with the sheer amount of manure produced by all the cattle, shipping all the manure is not possible and a fair amount of manure will end up traveling down watersheds and causing algae bloom in bodies of water. With high antibiotic use, people worry about the potential of feedlots breeding super drug resistant strains of bacteria also.
Criticism of CAFO’s are different in every country. In Europe, the precautionary principle came first, so GMO’s have been banned along with use of steroids on cattle, destroying CAFO’s. America on the other hand, has embraced the technology producing tons upon tons of corn beef. With no strong health benefits there is no clear winner. I just hope China has grass fed beef, so I don’t have to worry about ulcered cow stomach meat.”
Kevin even made this nifty chart-click to enlarge.
While we learned that the soil has 5 horizons (layers), we also learned that the second (A) horizon is the most important because it is the horizon where plants take root. This horizon is referred to as TOPSOIL, and is the main focus for farmers and anyone else trying to make a living from agriculture.
One of the key components plants need to grow is good, nutritious soil. Unfortunately, as plants continue to reuse the same soil over and over again it can become depleted of all important nutrients. This loss of soil quality over time is called SOIL DEGRADATION, a broad term that can be used to describe any soil that has suffered the effects of erosion, desertification, salinization, waterlogging, or decreased fertility. If left unchecked, soil degradation can leave patches of formerly high quality soil looking like this.
Unfortunately, during the 1930s there were no efforts to fight soil degradation and scenes like the one pictured above could be found all over the Midwest in the infamous Dust Bowl. Topsoil that was plowed over and over again, without any natural vegetation to anchor it, was picked up by the wind and blown for miles in the form of dust. So, in 1935, the United States passed the Soil Conservation and Domestic Allotment Act, a piece of legislation that educated farmer’s on techniques to avoid soil degradation, which in the long run saved thousands of acres of topsoil, important to the success of the farmers.
Farmers, who make their living essentially from the soil they own, must take action to conserve the soil they plant on in one of two ways. 1-Use proven agricultural techniques to slow or stop the process of soil degradation – 2. Restore the important nutrients time and time again after they are used up by plants.
As shown in choice number one above, there are a number of techniques to help improve SOIL CONSERVATION worldwide. The four main techniques for conserving soil are listed and shown below.
1. Terracing – Building up walls of land to counter the effect of a mountains slope leaving uniform flat surfaces to plant on.
2. Contour Planting/Strip Cropping – Similar to terracing, but building up soil walls along natural contour along the side of a hill or mountain.
3. Alley Cropping – Planting a row of crops, a row of trees, then a row of crops, etc. to avoid effects of wind erosion.
4. Windbreaks – Leaving previous vegetation, such as brush and small trees, around fields of crops, also to combat the effects of wind erosion.
If farmers worldwide continue to try and incorporate techniques such as these four, they may be able to reduce the 12 to 17 million acres of cropland lost per year to the effects of soil degradation.
Alum Richard Gee (’10) recently sent me this link to a The Economist article and map about which countries are growning genetically modified crops. I wish we had more time to spend on GMOs, but it was not meant to be this year. I’m not too concerned for you all on the AP exam as GMOs made it as a free response topic two years ago, so I doubt it will come around again this soon. Interesting regardless as this is becoming more prevalent as industrialized agriculture spreads. Key points from the brief article:
As can be seen in our map, GM technology has been enthusiastically embraced in the Americas and in many Asian countries. By contrast, many European countries are subject to severe restrictions on growing GM crops. Developing countries are planting GM crops at a more rapid rate than rich countries.
If you missed last Thursday and/or Friday, we finished watching King Corn. To recap, two Yale graduates made a documentary released in 2007 about growing an acre of corn in Iowa using methods of industrialized agriculture. You can borrow the DVD from me, or watch it on hulu.
We took a few moments to review the “high inputs” needed for industrialized crop and meat production featured in the film:
Click to Enlarge
I reminded folks that you must know the environmental impacts (“outputs”) that result from this type of agriculture. We did not take class time to review each of them, but they are detailed in your text.
We concluded the class by looking at the solution: organic agriculture.
Click to Enlarge
What is ironic is that it took the 1990 Organic Food Production Act to make legal a certification for the type of agriculture that was the norm before the Green Revolution. Organic agriculture is “low input” compared to industrialized agriculture, and the goal is sustainability. You can see the US standards for the USA Organic label here. Here are a few clips that show farms in England meeting the EU organic standard:
If you want to support local (less fossil fuels expended to deliver the calories), organic food you can always visit a area farmers market.
Today in class 2/21, we began the next unit on food production and soils. We began class by looking at The Hungry Planet: What the World Eats and comparing pictures of what families (around 5 people) ate over a week period. We compared what the families ate and the US dollars that would be spent on each week — for a typical family from Chad the costs was about $1.23 and for a typical American family the costs was about $350. We then related that information the the demographic transition — the wealthier a country is the more money they can spend on food and other items that might not be as necessary, things like processed foods and soda. Here are two links to the pictures that we looked at in class:
For additional reading, here is a link to a New York Times article that may help those of you who missed class. This article talks about new research that can explain better approaches to dieting and how to curb your appetite.
After the introduction, we began talking about Food Systems. The earth is made up of 25% land and 75% water. Of that land, we use about 38% of that for food production which is responsible for 93% of the calories that we take in from things like croplands for crops and rangelands for meats. The water on the other hand is responsible for 7% of the calories that we take in from things like fisheries and aquaculture.
For the more visual individuals, here is a picture of Mr. Willard’s organized notes:
After the introduction to Food Systems, we covered Farming. The two types of farming that we talked about were Industrialized and Traditional.
Industrialized Farming (aka conventional farming)
makes up about 80% of farming
has a high input of resources
high crop yield, meaning the land is very productive
typically monoculture, meaning only one type of crop is grown and harvested
Also has very many negative environmental impacts (which we will cover later)
Traditional Farming (aka subsistence farming )
makes up about 20% of farming
typically polyculture, meaning a variety of crops are grown and harvested
used by individuals who typically produce just enough for their family to get by