Bio 106, Lab 1, Spring 2012: Our Place in the World, Dr. P.C. Chabora

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1 Bio 106, Lab 1, Spring 2012: Our Place in the World, Dr. P.C. Chabora Objective: The goal of this exercise is to examine our resource demands and impacts on the Earth that stem from our day-to-day living. You may not be able to complete this in class, so do it at home. Introduction to populations and consumption: How much of the world s resources do we require? How much do we consume? What are the ecological factors, costs and consequences involved in providing for the things that we consume? One way of looking at this cost is by determining the size of our ecological footprint. What exactly does ecological footprint mean, how is it measured and just how big is it? And then, think about all those other people with whom we share the Earth what is their share of the Earth s resources? Can we afford to let them have a fair share? To illustrate these points, we will consider two simple cases of resource needs and consumption that are close to home and our everyday lives: Case 1 - Domestic water and waste: Considering yourself an average New Yorker, how much water do you use every day for domestic purposes? Where does the water used by the NYC population come from? How can we visualize our daily and annual water consumption? Now, think about the entire population of New York City and its daily consumption - and how do we estimate the quantity of water used daily? annually? How can we best visualize this? Then think about this: Where does the used water go? Again, visualize the amount of wastewater produced by the habitants of NYC. Also, as our consumption/waste changed over time, and if so, what accounts for those changes? Let s explore: Look up: then look at the left side of the home page where it has a scroll box of City Agencies. Scroll down and click on the agency Environmental DEP, then click on Drinking Water. Look at the map of reservoirs and supply lines ( Water Supply System Maps ) that supply NYC and then we ll look at our reservoirs, their capacities and current levels ( Reservoir Levels ). Then click on Drought and Water Consumption where we will examine our pattern of daily water consumption over the past 25 years. What factors account for the reduction in use? Remember that these values represent only water used for domestic purposes and do not include water in manufacturing, processing and most importantly, agriculture. You re going to need a tool for converting various measures to volumes. Conversion calculators for the MAC: use the unit conversion calculator in the dashboard widget. Others are available: or or If using a PC, a useful conversion utility is Convert.exe found at: So, what volume of water (in m 3 ) do you, the average New Yorker, use in a day? What is your annual domestic water consumption (in m 3 )? How can we visualize that quantity of water? Imagine filling the room you re in with water. Based on the DEP water consumption data and using the above calculations, calculate the rooms full of domestic water you would use per annum. Approximate volume of Colwin Hall 108: ~250 m 3 Approximate volume of SB-D-141: ~125 m 3 Approximate volume of the room you are occupying: m 3

2 How many rooms full (indicate which) of domestic water are you using per year? Discuss with the class the situation, concerning water, if you happened to be living in another country under different circumstances, for example Sudan, or rural Ethopia. Now consider the following: What happens to the water that we ve used? What volume (in m 3 ) of wastewater does each of us produce in a year? What volume of wastewater (in m 3 ) does the population of NYC produce in a year and where does it go? Again refer to then Environmental DEP, and check out Harbor Water - the wastewater processing by the 14 NYC plants that can treat about 1.4 billion gallons/day. Convert that amount of daily sewage into m 3. Consider the following: The total land area of all of NYC is approximately 785 square kilometers (303 square miles). (Note that there are 1,000,000 m 2 in a km 2.) If NYC was absolutely flat, without hills or dips, and was surrounded by a wall (imagine a huge 785 km 2 swimming pool), how deep would NYC be awash in wastewater after one year? N.B., (What does N.B. mean?) It is important to remember that the water consumption discussed above is only your domestic consumption and does not include the much greater usage of agriculture and manufacturing processes. We will return to these aspects later in this exercise. Case 2 - Beef and other food items: Consider, for a moment, the ecological costs of your hamburger. Let s simplify this question by not considering the environmental costs of growing, processing, shipping the wheat and materials used to make the roll, or the sauces, or pickles, lettuce and tomato, but just concentrate on the meat. How much beef does each of us, as average Americans, consume per year? What other costs are involved when considering the meat in your burger? Discuss in general terms, the overall costs of producing our food (land, water, chemicals such as fertilizer and pesticides, fuel for tractors and shipping, processing, water use in processing and cooking)? Let s investigate: Go to: Click on the top toolbar Data Sets, then click under Most Requested, Food Availability (per capita) Data System. Then click on Food Availability and then click on Spreadsheets. Choose a report, for example select and click on Beef, veal, pork, lamb and mutton, and total red meats to open the excel spreadsheet. Click on the tabs on the bottom of the sheet to select beef and then when the data are presented, look at the retail per capita availability values for the years where data are available. What is the annual per capita (US population) availability of beef? You can do similar inquiries with a large variety of all kinds of foods in our diet. Click back and different lists to explore a few different meats: (chicken, pork, fish ) and the try other commodities (string beans, watermelon, potatoes, wheat, rice ). What is the average per capita consumption of tomatoes?. Amazing! 2

3 So, how many people does one cow (= steer or heifer) feed in a year? Actually, for our purposes, let s say the average cow going to slaughter weighs 590 Kg. (1150 pounds) and after the waste is removed, yields about 570 pounds (258.1 Kg.) of prepared beef for market sales. This is roughly half the live weight. (See: Discuss the following: What items make-up this waste? What happens to this waste? So, how many people can feed on this one cow for a year? How many cows does it take to satisfy the beef appetite for the population of New York City? (Population of NYC is about 8,400,000 (rounded up) (See: the NYC.gov site for the Current Population Estimates at What are the environmental and land/water costs of raising the beef cattle stock to provide beef meat for NYC? How much feed and water are needed to raise a steer? How much water (in liters) is required to produce 1 Kg. of beef? (Try a web search engine such as Google.com, bing.com or Ask.com for information about that question! Keep in mind that there is a lot of controversy among the possible answers because it is so highly emotional and politically charged.) How much and what kind of waste does a steer produce? Estimates of the quantity of water required in the production of a pound, or Kg, of beef range from to. Be sure that you understand the arguments involved by the opposing sides that have generated these estimates. What do you think is the most reasonable estimate of the quantity of water needed to yield a Kg. of edible beef - and why? Let s now look at the larger picture using Ecological footprints: You can also try this at home actually, please do try this at home. Go to or any search engine and search for ecological footprint quiz, or use the links below, and have your family or friends try a quiz. Footprint quizzes: Do this quiz first, (Note that both sites have the same quiz) - click on this site, then click on ecological footprint quiz (left side of the page), or try If everyone on Earth lived the way you do, how many Earths would be required? Then try some of the other quizzes that are available they use different questions and formats. (A number of questions and topics are the similar, but the structure of the quiz and commentaries are different because it s based on various outlooks.) and How similar are these footprint quiz estimates? How could you account for any differences in estimates, if any 3

4 Human populations: Review the idea of the population pyramid and its interpretation and meaning. The United States Census Bureau web site is an extraordinary resource for U.S. and international population data. Population data and Pop Clocks: Under the category People and Households, click on International then click on International Data Base (IDB) Once at the IDB page, click on World Population Information located on the left side of the page, then you can click on Population Clocks to get a to the second estimate of the US and World population sizes. Click on World Vital Events per Time Unit to get an understanding of the increasing human population in very understandable and frightening terms. Look at the net gain of the population per year. To accommodate that many new people in a lifestyle of a developed nation is like adding a whole country with all its resource needs: space, agriculture, infrastructure, housing, roads, water supply, schools, and hospitals - everything that is necessary in a country with a population the size of Turkey! Go back to the International Data Base page and click on Data Assess, select a country, then explore those data. Examine the Demographic Indicators and Population Pyramids. Work together with your instructor and examine data from Afghanistan, Angola, Italy and U.S. You may then explore countries of your interest. CIA Fact Book: Check out various countries (starting with the ones you examined above for comparison) looking under the section on People. The data presented provide an interesting view of populations such as numbers in different age categories, median ages (a really telling statistic), and sex ratios at birth and at later ages, birth and death data, longevity, infant mortality, education, etc. More on Populations: There is a French website derived from an exhibition, originally designed when the human population approached six-billion, at the Musée del Homme, Museum National d Histoire Naturalle, Paris. Since then the website has been updated and expanded, but we do not have the time to explore today. You may explore it at your leisure and find it an interesting viewpoint: Resources and Sustainability: Here are two sites with a global view: WWF s Living Planet Report, year of the most current report: Examine this report, paying particularly attention to the items enumerated below (large document, long download). Study the charts, in particular, Fig. 22 on p (Ecological Footprint of Nations); Fig. 25 on p (Biocapacity); Fig. 28 on p (The Water Footprint of Consumption) and Fig. 29 on p (Water Footprint of Production). Check the summary tables beginning on p. 35. Note the total cubic meters of water used per individual for all purposes in the various countries, especially the USA. How does this value compare to our domestic use? Is there any wonder that clean water is one of the world s most limiting resources? 4

5 World Resources Institute: - explore Publications. Check out World Resources 2008: Roots on Resilience (Data Tables) (get there by clicking on Publications, Then view all then search for World Resources for the latest information) 5