Humans & the Environment

Ch.22

(22-1) Interconnected Planet

• Earth’s layers– Atmosphere: gases• Ozone layer• Climate• Greenhouse effect

– Hydrosphere: water– Geosphere: rock– Biosphere: part of Earth where life exists

Biodiversity

• Variety of life forms in an area• Species diversity– Richness: # of species in an area– Evenness: # of indiv.’s of each species in an area

• Genetic diversity: amt. of variation in the genetic material of all members of a pop.

(22-2) Environmental Issues

• Air Pollution– Smog: water vapor mixed w/ human-made chemicals– CFC’s & ozone thinning– Global warming– Acid precipitation: air pollutants combined w/ water

• Land & Water Pollution– Biological magnification: chemicals become more

concentrated in organisms higher on the food chain

Ecosystem Disruption

• Extinction: death of every member of a species– Endangered

• Ecosystem Imbalances– Keystone species: affects many other species in a

community• Ex: sea otter

Human Resource Use

• Primary production: total E stored through photosynthesis by terrestrial organisms

• Ecological footprint: human impact on ecosystems

• Sustainability: ability to meet human needs so the pop. can survive indefinitely

(22-3) Environmental Solutions

• Conservation Biology: i.d., protect, & manage natural areas w/ large biodiversity– Biodiversity hotspots– Bioindicator: species sensitive to ecological change

• Restoration Biology: plan ways to reverse changes & replace missing ecosystem components

Laws & Efforts

• Debt-for-nature swap: richer countries/org. pay debts if developing country takes preventative steps

• Ecotourism: supports cons. of ecologically unique areas while bringing economic benefit to locals

• Urban ecology: study of biodiversity in areas densely populated by humans