Medicine has contributed substantially, particularly in the development of vaccines and antibiotics to treat and prevent infectious disease). Agricultural advances have increased food production to support a larger population. Public health measures to provide clean drinking water to a greater proportion of the population have decreased the incidence of many diseases.

An ecological footprint is the amount of land and water required to produce the resources we need, and to help absorb our wastes. Sustainable living practices reduce the ecological footprint.

While Greensburg, Kansas, has a smaller ecological footprint than many American cities, it likely still has a larger footprint than a small hill-tribe village in Thailand. If there is no electricity in the village, the village will be using very few resources for heating and lighting. They may burn some wood for fires for cooking and heating, but as long as they are not burning trees at a rate greater than the forest is growing, wood is a renewable resource. The villagers likely do have any motorized vehicles, and likely are not relying on food that has been shipped long distances by air or truck. So they are likely not contributing to the burning of fossil fuels. Similarly, their clothes are likely to be made of local natural fibers, not synthetics that may require chemicals to produce.

Twenty single-family homes could add 80 people to this town if each family has 4 members. In a small town, 80 additional people could have a large impact (in a town of 800 people, this is a 10% increase). The additional families will require more water and produce more waste. By building on former crop land, the area has lost biological productivity, increasing the footprint. If the new condos are on the outskirts of town, the new residents will likely have to drive, increasing the amount of fossil fuels burned in the area. The condos will also increase the electrical usage of the town. If the new residents need to drive into and out of town for shopping and school or work needs (town residents may be able to walk to these destinations), the increase in the ecological footprint may be larger than the actual population increase.

The developer could consider sustainable energy sources to power the new condos, for example solar or wind power, as well as using sustainably sourced building materials. The developer could also consider providing convenient forms of shared transportation between the condos and the town to reduce fossil fuel consumption. The developer could consider putting in gardens for some food production could at least partly compensate for building on crop land.

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freshwater (R); coal (N); codfish populations (R); wind (R); sunlight (R)

Oil takes a very long time (millions of years) to form from organismal remains, so it is not renewable on a useful time scale.

There are many possibilities. In general, a renewable resource will become nonrenewable if it is being used at a faster rate than it can be replenished. For example, at one point the cod fishery of the North Atlantic was in danger of being depleted because so many fish were being caught at such a rate that they could not successfully reproduce to maintain the population. The fishery was restored by regulations that halted fishing and then placed restrictions on catches. As noted in the text, freshwater can become nonrenewable if it is being withdrawn from an aquifer faster than it can be replaced.

Answers will vary. Considerations include water conservation in dry areas, space availability for solar panels or wind farms in appropriate regions, resistance to the aesthetics (or lack thereof) of some of these installations, and their possible impact on wildlife.

“Sustainability” refers to living in a way that does not lead to enhanced depletion of resources. This includes minimizing use of nonrenewable resources, as well as choosing to use products that generate less waste.

LEED-certified buildings are designed to conserve energy, conserve water, send less waste to landfills, produce only limited amounts of greenhouse gases and generally be safe and healthy for the occupants (e.g. by using less toxic paints and furnishings).

There are many possibilities; Infographic 24.12 presents several concrete ideas.

Water is a major issue in the Southwest. Water is needed for crops, to sustain fish in rivers, and for human consumption, and is also used for recreational purposes—swimming pools, green lawns, and golf courses. All this places a large demand on the aquifers and rivers in the region. Many cities in this area are large and sprawling, requiring the use of cars to get around and thus increasing the demands for fossil fuels. Huge amounts of electricity are required in the summer to keep homes and businesses cool. Some of this electricity could be produced in a more sustainable fashion through solar power given the large number of sunny days every year.