Chapter 25 Flashcards
Exponential growth
A rate becomes more rapid over time
Carrying capacity
The maximum population the environment can support for an extended period
Growth rate
Calculated by birth rate minus death rate
Growth difference between MDCs, and LDCs
LDCs have a higher growth rate than MDCs
This is because LDCs don’t have access to most birth controls, so they end up sometimes having 8 or 9 children, and in MDCs, parents have jobs, so they can’t have 8 or 9 children.
Population growth
Population growth is expected to continue to rise due to:
- Moderate growth in MDCs
- Dramatic growth in LDCs
- Longer lifespan due to better healthcare
Why should you care about population growth
More people means: Greater use of and competition for resources: 1. Food 2. Water 3. Land 4. Energy And more pollution
Land
Land is essential because people need a place to live. Land is used for agriculture, electrical power plants, manufacturing plants, highways, hospitals, etc. Human usage of land has affected the quality of the earth. This causes deforestation, desertification, urbanization, etc. To help reduce their impact on land, humans could build upwards, rather than it all being directly on the ground.
Water
Water is used by industries, homes, and agriculturers.mWater comes from lakes, oceans, aquifers, etc. Human usage has affected water supplies by using too much water and polluting the water. To help reduce their impact on water supplies, humans can conserve water, and help clean the ocean, or stop pollution of the ocean.
Food
Food is the source of nutrients and energy for the body in order to survive. Food mainly comes from growing crops, raising animals, and fishing the seas. Humans have affected food by planting not enough genetic varieties, using heavy fertilizers, pesticides, herbicides, generous irrigation, and excessive fuel consumption. Humans can reduce their impact on food supplies by planting more variety, stopping the usage of pesticides and generous irrigation, and excessive fuel consumption.
Energy
Energy is basically the backbone of the modern world. Almost everything nowadays is possible because of energy. Energy comes from the burning of fossil fuels, hydropower, wind power, geothermal, etc. Humans are quickly running out of fossil fuels to burn, which I’d argue is a good thing because burning fossil fuels is bad for the environment. To help reduce their impact on energy sources, humans can switch to renewable sources.
Minerals
Minerals come from the earth’s crust and are typically extracted by humans. Minerals can be used to produce batteries, pesticides, medicines, paints, inks, and dyes. Humans have affected the earth greatly, because some of the minerals are toxic, and ruin the planet. Humans can reduce the impact on minerals by no longer digging for minerals.
Deforestation
The removal of trees
Desertification
The conversion of semiarid land to desertlike conditions
Salinity
Saltiness
Subsidence
A settling of soil as it dries out, as a result of groundwater depletion
Point sources
The source of contamination, when it’s from one place
Nonpoint sources
When contamination comes from many places
Renewable sources
Renewable sources are capable of being naturally replenished
Nonenewable sources
Nonrenewable sources are limited in supply
Hazardous wastes
Things that present a tremendous threat to our environment
These include:
Minerals
Synthesized chemicals
Raw sewage
Hazardous wastes come from:
Refineries
Factories
Hospitals
To help prevent these hazardous wastes from harming our planet, we can dispose of them properly.
Biodiversity
The variety of life on earth, and can be measured by looking at the number of species.
Causes of loss of biodiversity: Habitat loss: Accounts for the majority of loss of biodiversity Alien species Pollution Overexploitation Disease
Direct values of biodiversity
Medicinal, Agricultural, and Consumption use
Indirect values of biodiversity
Waste disposal, provision of freshwater, prevention of soil erosion, biogeochemical cycles, regulation of climate, and ecotourism
Sustainability
The ability to provide the same amount of goods and services for future generations, as is provided for the current generation, while preserving biodiversity
Today’s unsustainable society
Caused by the overpopulation of LDCs and over-consumption of MDCs.
