Humans in the Biosphere

Ch. 6

Human Interaction

There are four main activities by which humans affect the biosphere:– Hunting and Gathering– Agriculture– Industry– Urban Development

What are some of the effects we see/experience as a result of these activities?

Renewable and Nonrenewable Resources

Renewable Resources – resources that can be replenished or regenerate in a relatively short amount of time– Ex: trees, water, nutrients, etc.– Although they are renewable, some of the are

limited resources (not always readily available) Ex: Water can become a limited resource when there is a

drought

Renewable and Nonrenewable Resources

Human activity can affect the quality and supply of renewable resources such as– Land– Forests– Fisheries– Air– Fresh Water

Renewable and Nonrenewable Resources

Nonrenewable Resources – resources that cannot be replenished by natural processes– If they can be replenished, it takes millions and

millions of years to replace it– Ex: fossil fuels (coal, oil, natural gas)

Biodiversity

Biodiversity – the variety of organisms that are found on Earth

Types of biodiversity– Ecosystem diversity– Species diversity– Genetic diversity

Human activity can threaten and alter biodiversity

Threats to Biodiversity

Habitat alteration Demand for wildlife products Pollution

– Biological magnification – concentrations of harmful substances increase in organisms higher in the food chain

Introduced species– Invasive species – non-native species that rapidly reproduce

and “choke out” native species Ex: kudzu

Conserving Biodiversity

Conservation efforts usually focus on protecting various:– Species/Populations

bald eagle, koala, etc.

– Ecosystems National Parks Wilderness Areas Nature/Wildlife Preserves