Google Earth Assignment #4
Name: Cari Cooper
Question 1: Explain what is meant by urban metabolism?
Urban metabolism is the sum total of technical and socio-economic processes that occur in cities that result in growth, production of energy and elimination of waste. Karl Marx was the first person to talk of urban metabolism. He used this term to describe the material and energy exchange between nature and society when critiquing industrialization. He stated that urban metabolism will become a power in itself similar to capitalism and will control society unless society can control it.
Urban metabolism is similar to the body’s metabolism; it’s all about what goes in and what goes out. Like people some cities metabolize things faster and some are much slower accumulating more waste before disposing of it. Generally the larger the city the more resources are needed to satisfy the people but also more waste and pollution is generated. Topics concerned with urban metabolism are the outgoing flow of air pollutants, CO2, industrial waste, exported goods, heat, waste water and solid wastes as well as incoming flow of materials, goods, electricity, water, transportation fuel, food and industrial fuel.
Question 2: Zoom into the projects and read the Project Reports. Discuss one project from an environmental health perspective. What preventative measures were taken and how did it impact the community?
I chose the ASDF Sand Dam Project. I decided to pick this one from the map because it seemed to be the most rural and a little ways from where the others were located. This project is located in Mtito Andei a small town located between Nairobi and Mombasa in Kenya. For this project ASDF a foundation that helps farmers in arid and semi arid land gain access to clean water and with Kakai Self Help Group (which I believe is a group of locals). The team comprised of 22 men and 18 women who participated. This project is different from the usual water projects due to the acid land in this area. Due to the land a borehole type of well will not work and that is why a sand dam was built. First a section that has high seasonal water flow must be located, and then a concrete dam is built across the river. During the rainy season water collects behind the dam but also brings with it tons of sand and silt. It is estimated that 25-40% of what looks like just sand and silt is actually comprised of water. Once the dam is filled with sand and water, it flows over the dam ensuring that the river can be used by other residents downstream. At the bottom of the dam a plastic pipe with a tap on the end is placed. Members of the community then just turn the tap to get clean, sand filtered water year round. Sand dams provide an added bonus in that they usually help raise the local water table. This has great potential for local agriculture and can lead to beautiful oases. In this project the participants also included a shallow well and hand pump, planted trees, and created a seed bank.
This project set out to improve in these four areas: seed bank, shallow well excavation, terracing and tree growing and PHAST. The seed bank is still in process but a positive report is expected later this year. As for the shallow well excavation the project was completed in June of this year. Residents are using water from both the dam and shallow well for farming, livestock and domestic purposes. One resident describes how this has changed her life.Domitila Wanza describes how they used to walk 5miles to and froma well to obtain fresh water and not the whole process only takes 30 minutes. With his extra time, he has now saved his farm and livestock, planted trees and worked on other domestic activities including a new garden containing kale, tomatoes and onions that they can sell and raise their incomes. Slow process on terracing and tree growing due to preparation of a second well but targets and goals in this area are still expected to be completed on time. Lastly, the PHAST action plan was a great success. This plan covers pit latrine excavation, which has had a 91% success rate in those that were trained. The construction of utensil racks hasan implementation rate of 82%, tippy tap hand washing area has a success rate of 91%, and digging of rubbish pits with 91% implemented. And lastly, boiling of drinking water showing an 82% success rate. Although there is still work to do and improvements to be made this sand dam has made vast improvements in the quality of life for the residents of Mtito Andei.
Question 3: Discuss one map relating directly to a topic/term from Chapter 7 of your textbook.
I picked the map of urban slums. I have always thought the pictures of these slums are so interesting and that we as American’s take a lot for advantage. I think a lot at night about the people who live in these slums as I drift off to sleep on my Sleep Number bed. As of 2001 there were close to 1 billion people or 15% of the world’s population living in these types of housings. Unfortunately, since the people living in these dwellings are poor and have little resources or incentive to improve, not many of these slums have seen many improvements. Although slums are found in almost every territory, South America and North Africa have the largest amount of residents living in urban slums, 26% and 25% respectively. I was somewhat surprised that Southern Asia showed much lower percentages than I expected about 17%. I guess it is the images I have seen and read about India making me think that this area would be the largest. There was no surprise that Japan had the lowest rates with about 5%, I often think of the Japanese living in modern contemporary dwellings. North America coming in with about 7% of it’s residents living in urban slums. I would be extremely interested in what factors qualify a dwelling in the US to be considered an “urban slum”.
Question 4: Choose two maps to compare and contrast. How does the information relate and why?
I decided to compare and contrast the smoking in men and women. The differences are extremely interesting. For men that smoke Asia Pacific, Middle East, Eastern Asia, and Eastern Europe and Japan all having high numbers very close or higher than 50% with the country of Yemen being number one at 77%. However in Asia Pacific, Middle East, Eastern Asia (between 3-9%) women have some of the lowest smoking percentages compared to their male counterparts in their countries. Making me suspect that societal images of smoking is a giant factor as to whether these woman smoke. Although more men in South America smoke about 37% than South American women about 24%, South America has the second highest smoking rates in the world only being beat out by Western Europe by 2 percent. The second thing that I have noticed is the fact that worldwide men have higher percentages of smoking with the lowest differences between men being about 15 percent more. Sadly, the two lowest areas for male smokers are North America and Southern Asia but with the percents still around 30%.
Question 5: Describe how a constructed or natural wetland purifies wastewater.
New York City uses a constructed Waste Water Treatment System. Due to the large size of New York City, it has to use a constructed water treatment system. This system which is a typical one of this type, takes only about 7 hours and uses a five-step process. This process uses five major steps, which include preliminary treatment, primary treatment, secondary treatment, disinfection and lastly a sludge treatment. During the primary and secondary treatments 85-95% of pollutants are removed from the wastewater, During the preliminary treatment process wastewater called influent passes through screens and bars remove large trash items such as sticks, newspapers, cans and bottles. Next the wastewater is lifted from the screen into the surface level of the plant. Now the water has entered into the primary treatment area. This area consists of large tanks called sedimentation tanks and stays there for one to two hours. This is done so that larger solids settle to the bottom and it also allows lighter materials to float, which can easily be skimmed of the top of these tanks. The solids that sunk are called primary sludge and are then pumped through cyclone degritters. These cyclone degritters use centrifugal force to separate out grit, sand and gravel. The degritted sludge is then pumped to a different area of the plant for further processing. The next step is secondary treatment also called activated sludge process. Next air is pumped into large aeration tanks which is then mixed with the wastewater and sludge this process stimulates the growth of oxygen-using bacteria and other tiny organisms that are already present in sewage. These microorganisms consume most of the remaining inorganic material in the polluting water. The secondary treatment takes up the bulk of time about 3-6 hours. Next the water goes through a similar process as the primary treatment where it goes to a final settling tank where heavier particles settle to the bottom as secondary sludge. This sludge is once again taken away for further processing. After both primary and secondary treatment, disease-causing organisms may still remain in wastewater. The next step is to disinfect and kill harmful organisms. In the disinfection stage, wastewater spends a minimum of 15-20 minutes in a chlorine-contact tanks and mixes with sodium hypochlorite (household bleach). This treated water is then released to local waterways. The last and final step is sludge treatment. On the other side of the plant where sludge was brought from both primary and secondary treatment the sludge is processed. Amazingly this sludge consists of 99% water and must be thickened for to process further. The sludge is then placed in thickening tanks for 24 hours. After the thickening is complete the sludge is placed in oxygen free tanks called digesters, where it is heated to at least 95 degrees Fahrenheit for between 15-20 days. This process stimulates growth of anaerobic bacteria, which will consume the organic material. After the digestion process, the sludge is black, has a consistency of pea soup and his little odor and is now called digested sludge. The digested sludge is then pumped from storage tanks to a dewatering facility. At the dewatering area sludge is sent though large centrifuges that operate like the spin cycle in your washing machine. This process removes about 90% liquid and creates a substance called biosolids and organic polymer is added to make more of a cake like consistency. The biosolids now have many uses such as fertilizers, soil conditioners that can be spread on golf courses, lawns or parks or spread over inactive landfills.
Question 6: Describe geographically the relationships and patterns you found in these statistics.
There is an obvious correlation between these four items. For the populations which were low on using both improved sanitation and improved waters supplies such as India, Central Africa, and Bolivia these same areas having high rates of both infant mortality and populations that live below $2 a day. Some of the lowest rates for regions using improved sanitation are India with 21% Bolivia with 9%, Chad and Liberia with only 4%. With the highest countries using improved sanitation being both Australia and Japan at 100%, the United States at 99% and also many countries in Europe with 100% as well. Most of Central Africa being the lowest in using improved water supplies with numbers between 30 and 50 percent and Mongolia with Afghanistan having one of the lower numbers at 39% as well. Similar to sanitation; Australia, Japan, Europe and the United States all having the highest numbers when it comes to using improved water supply. Countries with the highest infant mortality rates are mostly in Central Africa and Mongolia both of these areas scoring low on improved sanitation and water use indicating that access to acceptable sanitation and clean water helps improve infants chance of survival. Also the countries listed highest at using improved sanitation and water have the lowest infant mortality rates such as Japan with only 2.6% and Australia at 3.9 % and also North America and Europe all having low infant mortality numbers as well. When looking at countries that have the largest percent of people living on $2 a day, you see the same trend. Central Africa and India were in the top with much of Central Africa’s population in this category with some countries having 90% of its population living in these conditions. Overall, it is obvious that countries who are not using improved sanitation and improved water are poor and have less resources and who have higher rates of infant mortality due to that and their access to decent sanitation removal and clean water.
Question 7: How and why do modern landfills deal with methane gas?
LFG (Landfill Gas) is extracted from landfills using several wells and blower/flare or vacuum systems. The gas is pushed to a central location where it can be processed and treated. Here the gas can be flared if it is to be used to generate electricity, replace fossil fuels in industrial or manufacturing operations. LFG located at this central site can also be upgraded to a pipeline-quality gas where the gas can be used directly or further processed as an alternative to vehicle fuel.
Modern landfills deal with methane gas because it can be captured, converted and used as an energy source. When LFG is captured properly, it helps prevent methane from migrating in the atmosphere and eliminates smog and global climate change. The EPA lists several reasons as to why LFG is used and how. According to the EPA; LFG helps destroy methane emissions which is a potential heat-trapping gas, generates renewable energy that offsets the use of non-renewable resources such as coal, oil and natural gas, is a cost-effective option for reducing methane emissions while still generating energy, helps reduce local air pollution and creates jobs, revenues. When LFG is converted to energy it can be used to fuel your car, fire your pottery, process your food or treat your wastewater.
Question 8: Briefly argue the positives of urban slums, including the health benefits.
I do feel an urban slum has many advantages to living poorly in a rural area. I also believe like the author of this article that these slums have great potential. A poor urban slum can go to a good or great thriving city with time. Urbanization can and does work in many areas but this does not happen overnight. It may have taken a hundred years but if you go back to the exact same locations that new immigrants lived in New York City when they lived in tenets or (slums), I doubt the apartment in that area now can even be afforded by the average American. Cities such as Chicago in the 19th century, Tokyo in the mid 20th century and most recently Mumbai (formerly Bombay) have started out with mostly “slum” areas and are now are extremely world-class, popular, thriving cities that have made urbanization work for them.
I do believe that the urban slums bring more entrepreneur opportunities than a rural life can usually provide. Although most will end up still being poor there is still more of a chance for success. Once again rare but Edward Glaesar author of the article did point out several success stories and when it comes down to it I believe these success stories of true entrepreneur success are rare in the general population as well. I do believe like mentioned in the article that a key factor for these slums to be successful is to link them to areas of the city with more money and resources. These slums also have economic benefits with cities allowing half of the population to live on around 4 percent of the land, which leaves more space for open country. Because developing cities are so dense they use far fewer resources mostly due to the fact that poor people don’t consume as much. In general city dwellers tread more lightly on resources. The roads in the city areas are shorter as are sewer lines as well as power lines. Apartment use much less energy to heat, cool and light. Because of the density of the city these people also drive less, which makes carbon emissions in cities like New York much lower than the national average.
A benefit not mentioned in the article but something I personally see that can be a positive factor for living in urban slums is socialization. More people now surround many of these people who came from small rural villages and areas. It is not just imagination that two or a few people may be able to get together, pull their resources and come up with a successful idea to improve their status and lives.