ENV330

ENV330 Module 4 AVP Transcript Title Slide Narrator: In Module 4, we will consider the impact of food production and distribution and sustainable food production. The total amount of food grown and produced for humans has increased dramatically over the past 50 years to meet the growing demands of our human population. Agricultural production, meat production and fish catch, both wild caught and aquaculture have all increased dramatically. The world’s three largest grain-producing countries are China, the United States, and India. What kinds of stresses has this placed on the natural capital and ecosystems of the world? Slide 2 Title: Impacts of Food Production Slide content: [image of a desert] Narrator: The impacts include loss of biodiversity, soil degradation, wasting and pollution of scarce water resources, increased greenhouse gas emissions, depletion of fish stocks in the oceans, and human health problems. According to a 2002 study by the United Nations, nearly 30% of the world’s cropland has been degraded to some degree by soil erosion, salt buildup, and chemical pollution, and 17% has been seriously degraded. There are serious soil erosion problems on every continent of the world, and marine biologists say that we’ve “fished out” much of the oceans. Slide 3 Title: Dust Bowl in 1930’s Slide Content: [black and white image of a dust cloud taking over a town] Narrator: Overgrazing, poor agricultural practices including salinization from irrigation can cause erosion, desertification and dust storms. Deforestation of hillsides can also impact agriculture and ecosystems. Once a hillside has been deforested for timber, fuelwood, livestock grazing, or unsustainable farming, water from precipitation rushes down the denuded slopes, erodes precious topsoil, and can increase flooding and pollution in local streams. Such deforestation can also increase landslides and mudflows. A 3,000-year-old Chinese proverb says, “To protect your rivers, protect your mountains.” Waste of water is one of the major environmental problems associated with agriculture. The most efficient (90-95%) way to get water to the roots of crops is through drip irrigation, or Low Energy Precision Application (LEPA), which you will learn about in this module. During the Dust Bowl in the US in the 1930’s, terribly unsustainable agricultural practices in the Midwest breadbasket led to such dire conditions that millions of starving people migrated away from the farmlands. Many children died from inhaling the dust. The situation got so bad that during a Senate hearing on the issue in DC, dust from a dust storm leaked into the conference room! A few inches of top soil is all that keeps civilization from starvation – we need to protect this vital natural capital. Slide 4

Title: Industrialized Agriculture Slide Content: [image of farm equipment on an empty field] Narrator: Industrialized agriculture uses about 17% of all commercial energy used in the US. 5% is for used for transporting food the average 1300 miles from farm to plate in the US. The resulting pollution degrades the air and water. What effects do you think industrialized agriculture has on Global Climate Change? As Rajendra Pachauri, head of the UN Intergovernmental Panel on Climate Change puts it, “We need to start eating as if Earth’s climate mattered.” Chemical pesticides used in industrial agriculture are another issue with grave ecological and environmental effects. Farmers use many tons of them on every crop leading to genetic resistance by insects and other agricultural pests, pollution of steams and poisoning of wildlife, contamination of food, and they kill natural pests’ enemies. Organic farming avoids these problems. Additionally, there are many ways to protect soil and minimize erosion, including: terracing, contour plowing, strip cropping, alley cropping, and windbreaks. You will learn about these and other sustainable farming techniques in this module. Slide 5 Title: Factory Meat Farming Slide Content: [image of pigs in a barn] Narrator: The US grows and kills nearly 10 billion animals a year despite making up only 4.5% of the world’s population. The use of animal feedlots has increased dramatically during the last few decades. In addition to the ethical issues related to animal cruelty in horrendously crowded conditions, many serious environmental problems are caused by feedlots and factory meat farming. For example, the concentrated poultry and hog houses produce as much sewage as cities, leading to eutrophication problems in streams, rivers and coastal areas when the nutrients enter those waters. The excess nutrients stimulate rapid algal growth, called an algal “bloom”. The water becomes cloudy and blocks the light leading to massive die-off of the algae. Microbial decomposition uses up most of the dissolved O2 , leading to massive “dead zones” in which fish and other animals suffocate. Meat production also requires much more energy than growing grain. Due again to the 2

nd Law of

Energy, and the energy pyramid, up to 90% of the energy in grain fed to animals is converted into low quality waste heat energy. Therefore, it takes 7 lbs. of grain to create 1 lb. of beef, and 4 lbs. of grain to produce 1 lb. of pork. The efficiency of producing chicken and fish is much higher – a 45% and 50% conversion of grain energy to meat energy. Of course, a vegetarian diet eliminates all of this lost food energy. Aquaculture, the raising of seafood in large enclosures, offers some advantages but also has disadvantages. You will learn about aquaculture in this module. QUESTION: Why do most people in poor overpopulated societies subsist mainly on a vegetarian diet?

Yes, it’s much more efficient to feed the crops directly to people and thereby eliminate the inefficient conversion of plants to meat with up to 90% conversion of plant energy to waste heat energy due to the 2

nd Law of Energy. You can feed 10-20 times as many people from the same amount of land if you

eliminate the livestock. ANOTHER QUESTION: Who will eat meat when the human population of the Earth doubles again to 12 or 13 billion? Answer: Perhaps no one!! It could become a distant memory only remembered in tales told by old grandfathers. ETHICAL QUESTION: Is it ethical to eat meat on an overcrowded planet where thousands of children die from malnutrition each day? I’m going to let you ponder those questions. And while you are pondering, we can all help by wasting less food, eating less or no meat, using organic farming to grow some of our own food, buying organic food, eating locally grown food, and composting . To create sustainable agriculture we need to mimic nature. End of Presentation