DMC-104: Geography and EnvironmentCourse Teacher: Dr. Syed Hafizur Rahman (SHR)

M. Sc. (JU), Ph. D. (Birmingham University, United Kingdom)

Permanent PositionProfessorDepartment of Environmental SciencesJahangirnagar University, Dhaka-1342

E-mail: hafizsr@yahoo.com

Day & Time: 03:00 to 04:00PM (Wed & Thu)

Last LectureHuman Geography:

Human Society and the Earth (The Human Environment, Population Growth and Distribution, Global Urbanization, Global Time and Time Zones),

Climate and Human Societies (Climate and Human Settlement, Flood Control, Atmospheric Pollution, Disease and Climate),

Exploration and Transportation (Exploration and Historical Trade Routes, Road Transportation, Railroads, Air Transportation).

This Lecture

Economic Geography: Agriculture (Traditional Agriculture,

Commercial Agriculture, Modern Agricultural Problems, World Food Supplies),

Energy and Engineering (Energy Sources, Alternative Energies, Engineering Projects),

Industry and Trade (Minerals, Manufacturing, Globalization of Manufacturing and Trade, Modern World Trade Patterns).

Agriculture

Traditional Agriculture• Two agricultural practices that are widespread among

the world’s traditional cultures, slash-and-burn and nomadism, share several common features.

• Both are ancient forms of agriculture, both involve farmers not remaining in a fixed location, and both can pose serious environmental threats if practiced in a nonsustainable fashion.

• The most significant difference between the two forms is that slash-and-burn generally is associated with raising field crops, while nomadism as a rule involves herding livestock.

Slash-and-burn• Slash-and-burn acquired its name from the practice of

farmers who cleared land for planting crops by cutting down the trees or brush on the land and then burning the fallen timber on the site.

• The farmers literally slash and burn. The ashes of the burnt wood add minerals to the soil, which temporarily improves its fertility.

• Crops the first year following clearing and burning are generally the best crops the site will provide.

• Each year after that, the yield diminishes slightly as the fertility of the soil is depleted.

Nomadism• Nomadic peoples have no permanent homes. They earn

their livings by raising herd animals, such as sheep, cattle, or horses, and they spend their lives following their herds from pasture to pasture with the seasons.

• Most nomadic animals tend to be hardy breeds of goats, sheep, or cattle that can withstand hardship and live on marginal lands.

• Traditional nomads rely on natural pasturage to support their herds and grow no grains or hay for themselves.

• If a drought occurs or a traditional pasturing site is unavailable, they can lose most of their herds to starvation.

Commercial Agriculture• Commercial farmers are those who sell substantial portions of

their output of crops, livestock, and dairy products for cash. • In some regions, commercial agriculture is as old as recorded

history, but only in the twentieth century did the majority of farmers come to participate in it.

• For individual farmers, this has offered the prospect of larger income and the opportunity to buy a wider range of products.

• For society, commercial agriculture has been associated with specialization and increased productivity.

• Commercial agriculture has enabled world food production to increase more rapidly than world population, improving nutrition levels for millions of people.

Steps in Commercial AgricultureIn order for commercial agriculture to exist, products must

move from farmer to ultimate consumer, usually through six stages:

1. Processing, packaging, and preserving to protect the products and reduce their bulk to facilitate shipping.

2. Transport to specialized processing facilities and to final consumers.

3. Networks of merchant middlemen who buy products in bulk from farmers and processors and sell them to final consumers.

Steps in Commercial Agriculture4. Specialized suppliers of inputs to farmers, such as seed,

livestock feed, chemical inputs (fertilizers, insecticides, pesticides, soil conditioners), and equipment.

5. A market for land, so that farmers can buy or lease the land they need.

6. Specialized financial services, especially loans to enable farmers to buy land and other inputs before they receive sales revenues.

Improvements in agricultural science and technology have resulted from extensive research programs by government, business firms, and universities.

World Food Supplies• All living things need food to begin the life process and to

live, grow, work, and survive. Almost all foods that humans consume come from plants and animals.

• Not all of Earth’s people eat the same foods, however, nor do they require the same caloric intakes.

• The types, combinations, and amounts of food consumed by different peoples depend upon historic, socioeconomic, and environmental factors.

• Early in human history, people ate what they could gather or scavenge. Later, people ate what they could plant and harvest and what animals they could domesticate and raise.

World Food Supplies• Modern people eat what they can grow, raise, or purchase.

Their diets or food composition are determined by income, local customs, religion or food biases, and advertising.

• There is a global food market, and many people can select what they want to eat and when they eat it according to the prices they can pay and what is available.

• At the current pace of hunger reduction in the world, 600 million will suffer from “acute food insecurity” and go to sleep hungry in 2015.

• Despite efforts being made to feed the world, outbreaks of food deficiencies, mass starvation, and famine are a certainty in the twenty-first century.

World Food Source Regions• Agriculture and related primary food production activities, such

as fishing, hunting, and gathering, continue to employ more than one-third of the world’s labor force.

• Agriculture’s relative importance in the world economic system has declined with urbanization and industrialization, but it still plays a vital role in human survival and general economic growth.

• Agriculture in the third millennium must supply food to an increasing world population of nonfood producers.

• It must also produce food and nonfood crude materials for industry, accumulate capital needed for further economic growth, and allow workers from rural areas to enter industrial, construction, and expanding intra-urban service functions.

World Food Source Regions• Soil types, topography, weather, climate, socioeconomic

history, location, population pressures, dietary preferences, stages in modern agricultural development, and governmental policies combine to give a distinctive personality to regional agricultural characteristics.

• Two of the most productive food-producing regions of the world are North America and Europe.

• Countries in these regions export large amounts of food to other parts of the world.

• About 90 percent of the rate of increase in aggregate food demand in the early twenty-first century is expected to be the result of population increases.

• Factors that could lead to larger fluctuations in food availability include weather variations such as those induced by El Niño and climatic change, the growing scarcity of water, civil strife and political instability, and declining food aid.

• In developing countries, decision makers need to ensure that policies promote broad-based economic growth—and in particular agricultural growth—so that their countries can produce enough food to feed themselves or enough income to buy the necessary food on the world market.

Energy and Engineering

Energy Sources• Energy is essential for powering the processes of

modern industrial society: refining ores, manufacturing products, moving vehicles, heating buildings, and powering appliances.

• In 1999 energy costs were half a trillion dollars in the United States alone.

• All technological progress has been based on harnessing more energy and using it more effectively.

• Energy use has been shaped by geography and also has shaped economic and political geography.

Ancient to Modern Energy• Energy use in traditional tribal societies illustrates all

aspects of energy use that apply in modern human societies.

• Early Stone Age peoples had only their own muscle power, fueled by meat and raw vegetable matter.

• Warmth for living came from tropical or subtropical climates.

• Then a new energy source, fire, came into use. It made cold climates livable. It enabled the cooking of roots, grains, and heavy animal bones, vastly increasing the edible food supply. Its heat also hardened wood tools, cured pottery, and eventually allowed metalworking.

Energy Sources• Biomass—wood or other vegetable matter that can be

burned—is still the most important energy source in much of the world. Biomass fuels are often agricultural or forestry wastes.

• Fossil fuels have more concentrated chemical energy than biomass. Underground heat and pressure compacts trees and swampy brush into the progressively more energy-concentrated peat, lignite coal, bituminous coal, and anthracite or black coal, which is mostly carbon.

• Large deposits of coal are still available, but growth in the use of coal slowed by the mid-twentieth century because of two competing fossil fuels, petroleum and natural gas.

Energy Sources• Petroleum includes gasoline, diesel fuel, and fuel oil. It

forms from remains of one-celled plants and animals in the ocean that decompose from sugars into simpler hydrogen and carbon compounds (hydrocarbons).

• There are also hydrocarbon gases associated with petroleum and coal. The most common is the natural gas methane. Methane does not have the energy density of hydrocarbon liquids, but it burns cleanly and is a fuel of choice for end uses such as heating homes and businesses.

• Heat engines transform the potential of chemical energies. Auto and diesel engines burn fuel inside the engine (internal combustion), and the hot gases expand through pistons to make mechanical motion.

Energy Sources• Heat engines can create energy from other sources, such as

concentrated sunlight, nuclear fission, or nuclear fusion. • The electrical generator transforms mechanical motion into

electricity that can move by wire to uses far away.• Such transportation (or wheeling) of electricity means that

one power plant can serve many customers in different locations.

• Flowing water and wind are two of the oldest sources of industrial power.

• Solar energy can be tapped directly for heat or to make electricity. Although sunlight is free, it is not concentrated energy, so getting usable energy requires more equipment cost.

Future Energy Sources• Possible future energy sources are nuclear fission,

nuclear fusion, geothermal heat, and tides. • Fission reactors contain a critical mass of radioactive

heavy elements that sustains a chain reaction of atoms splitting (fissioning) into lighter elements—releasing heat to run a steam turbine.

• Tremendous amounts of fission energy are available, but reactor costs and safety issues have kept nuclear prices higher than that of coal.

Energy and Environment• Energy affects the environment in three major ways.

First, firewood gathering in underdeveloped countries contributes to deforestation and resulting erosion.

• Although more efficient stoves and small solar cookers have been designed, efficiency increases are competing against population increases.

• Energy production also frequently causes toxic pollutant by-products. Sulfur dioxide (from sulfur impurities in coal and oil) and nitrogen oxides (from nitrogen being formed during combustion) damage lungs and corrode the surfaces of buildings.

Energy and Environment• Lead additives in gasoline make internal combustion

engines run more efficiently, but they cause low-grade lead poisoning.

• Spent radioactive fuel from nuclear fission reactors is so poisonous that it must be guarded for centuries.

• Finally, carbon dioxide from the burning of fossil fuels may be accelerating the greenhouse effect, whereby atmospheric carbon dioxide slows the planetary loss of heat. If the effect is as strong as some research suggests, global temperatures may increase several degrees on average in the twenty-first century, with unknown effects on climate and sea level.

Engineering Projects

• Human beings attempt to overcome the physical landscape by building forms and structures on the earth.

• Most structures are small scale, like houses, telephone poles, and schools.

• Other structures are great engineering works, such as hydroelectric projects, dams, canals, tunnels, bridges, and buildings.

Engineering Works and Environmental Problems

• Although engineering allows humans to overcome natural obstacles, works of engineering often have unintended consequences.

• Many engineering projects have caused unanticipated• environmental problems.• Dams, for instance, create large lakes behind them by

trapping water that is released slowly. This water typically contains silt and other material that eventually would have formed soil downstream had the water been allowed to flow naturally.

Engineering Works and Environmental Problems

• Instead, the silt builds up behind the dam, eventually diminishing the lake’s usefulness. As an additional consequence, there is less silt available for soil-building downstream.

• Canals also can cause environmental harm by diverting water from its natural course. The river from which water is diverted may dry up, negatively affecting fish, animals, and the people who live downstream.

• The benefits of engineering works must be weighed against the damage they do to the environment.

• They may be worthwhile, but they are neither all good nor all bad: There are benefits and drawbacks in building any engineering project.

Industry and Trade: Minerals• Mineral resources make up all the nonliving matter found in

the earth, its atmosphere, and its waters that are useful to humankind.

• The great ages of history are classified by the resources that were exploited.

• First came the Stone Age, when flint was used to make tools and weapons. The Bronze Age followed; it was a time when metals such as copper and tin began to be extracted and used.

• Finally came the Iron Age, the time of steel and other ferrous alloys that required higher temperatures and more sophisticated metallurgy.

Industry and Trade: Minerals• Metals, however, are not the whole story—economic progress

also requires fossil fuels such as coal, oil, natural gas, tar sands, or oil shale as energy sources.

• Beyond metals and fuels, there are a host of mineral resources that make modern life possible: building stone, salt, atmospheric gases (oxygen, nitrogen), fertilizer minerals (phosphates, nitrates, and potash), sulfur, quartz, clay, asbestos, and diamonds are some examples.

• Underground mines can extend as far as a mile into the earth and are subject to cave-ins, water leakage, and dangerous gases that can explode or suffocate miners.

• Safety is an overriding issue in deep mines, and there is legislation in many countries designed to regulate mine safety and to enforce practices that reduce hazards to the miners from breathing dust or gases.

Manufacturing• Manufacturing is the process by which value is added to

materials by changing their physical form—shape, function, or composition.

• For example, an automobile is manufactured by piecing together thousands of different component parts, such as seats, bumpers, and tires.

• The component parts in unassembled form have little or no utility, but pieced together to produce a fully functional automobile, the resulting product has significant utility.

• The more utility something has, the greater its value. In other words, the value of the component parts increases when they are combined with the other parts to produce a useful product.

Employment in Manufacturing• On a global scale, only 20 percent of the world’s working

population had jobs in the manufacturing sector at the end of the twentieth century.

• The rest worked in agriculture and mining (49 percent) and services (31 percent). The importance of each of these sectors varies from country to country and from time period to time period.

• High-income countries have a higher percentage of their labor force employed in manufacturing than low-income countries do.

• Every country produces manufactured goods, but the vast bulk of manufacturing activity is concentrated geographically in three major manufacturing regions—eastern North America, Europe, and eastern Asia.

• Together, these three regions produce more than 85 percent of the world’s manufacturing output.

• In fact, three countries—the United States, Japan, and Germany—produce almost 60 percent of the world’s manufactured goods.

• The global economy of the twenty-first century presents a wide variety of opportunities and challenges. Sophisticated communications and transportation networks provide increasing numbers of manufacturing companies with more choices as to where to locate their factories.

• However, high-income countries like the United States are increasingly in competition with other countries (both high- and low income) to maintain existing manufacturing investments and attract new ones.

The World Trade Organization and Global Trading• In 1998 domestic political pressures and an expected domestic

surplus of rice prompted the Japanese government to unilaterally implement a 355 percent tariff on foreign rice, violating the United Nations’ General Agreement on Tariffs and Trade (GATT).

• On April 1, 1999, Japan agreed to return to GATT import levels and imposed new over-quota tariffs. While domestic Japanese politics could have prompted a trade war with rice exporting countries, the crisis demonstrates how multilateral trading initiatives promote stability.

• Without an agreement, rice exporters might not have gained access to Japanese markets. By returning to GATT minimum quotas and implementing over-quota taxes, the compromise addressed the interests of both domestic and foreign rice growers.

Modern World Trade Patterns• Trade, its routes, and its patterns are an integral part of

modern society. Trade is primarily based on need. People trade the goods that they have, including money, to obtain the goods that they don’t have.

• Some nations are very rich in agriculture or natural resources, while others are centers of industrial or technical activity.

• Because nations’ needs change only slowly, trade routes and trading patterns develop that last for long periods of time.

Trade Patterns• For many years, world populations were coast centered.

This means that most of the people in the country lived close to the coast. This was due primarily to the availability of water transportation systems to move both goods and people.

• At this time, major railroad, highway and airline systems did not exist. As railroad and highway systems pushed into the interiors of nations, the population followed, and goods were needed as well as produced in these areas.

• Thus, over the years many inland population centers have developed that require transportation systems to move goods into and away from this area.

Trade Patterns• In these cases, international trade to these inland centers

required the use of a number of different modes of transportation.

• Each of the different modes required additional paperwork and time for repackaging and securing of the cargo. For example, cargo coming off ships from overseas was unloaded and placed in warehouse storage.

• At some later time, it was loaded onto trucks that carried it to railyards.

• There it would be unloaded, stored, and then loaded onto railcars. At the destination, the cargo would once again be shifted to trucks for the final delivery. During the course of the trip, the cargo would have been handled a number of times, with the possibility of damage or loss occurring each time.

Next LecturePolitical Geography