Studying the State of our Earth Chapter 1

What is Environmental Science? Environmental Science: field that looks at interactions among human systems and those found in nature

Natural Resources Renewable Natural Resource Nonrenewable Natural Resource Replenished over short periods of time Available in finite supply and formed much more slowly Once depleted, no longer available Sunlight, wind, soil, waterMineral ores, crude oil

System: set of interacting components that influence one another by exchanging energy or materials a. environmental system (man-made or natural) - ecosystem: includes biotic and abiotic components

Humans Altering Natural Systems Humans manipulate environment more than any other species intentionally and unintentionally Human activities have created opportunities for certain species to thrive As the human population grows, their effect on the environment will grow

Environmental services: provided by natural environment such as clean water, timber, fisheries Environmental indicators: describe current state of environment ex) human population, extinction rate - used to help guide towards sustainability - five global (biodiversity, food production, carbon dioxide concentrations, human population and resource depletion)

Biological Diversity or Biodiversity “diversity of life forms in an environment” 3 scales a. genetic, species, and ecosystem diversity Important indicator of environmental health and quality

Genetic diversity: measure of genetic variation among individuals in a population a. high genetic diversity = responding to environmental change

Species Diversity: number of species in a region or in a particular type of habitat a. critical environmental indicator ex) frogs for environmental health b. speciation: evolution of new species

Ecosystem diversity: measure of the diversity of ecosystems or habitats that exist in a given region a. land area is used as a measurement of biodiversity (hectares  ha)

Food Production Ability to grow food and nourish the human population Wheat, corn and rice Food shortages have led to higher food prices

Average Global Surface Temperature and Carbon Dioxide Concentrations Greenhouse gases: heat trapping gases ex) CO 2 a. help keep Earth’s surface within a range of temperatures b. have risen over time (anthropogenic reasons) ce%20AP/Art%20Notebook/friedland_ch01.pdf

Human Population Current population: 6.9 billion and growing Agricultural Revolution Industrial Revolution

Resource Depletion As the human population increases, the resources needed for survival decreases Renewable (timber) and nonrenewable (coal) Tragedy of the Commons - resources become overused due to unregulated exploitation - Garret Hardin - Easter Island

Ecological Footprint “the output from the total amount of land required to support a person’s lifestyle” Unsustainable living v. Sustainable living Human Ecological Footprint = 14 billion hectares (______ acres?)  125% of Earth’s total usable land area

Scientific Method

Controlled v. Natural Experiments Controlled Experiments a. controlled settings such as laboratory Natural Experiments a. environment b. example: volcano destroying large amounts of land showing forest regrowth

Unique Challenges in Environmental Science Lack of Baseline data: no “control planet” Subjectivity Interactions Human Well-Being

Sustainable Development Obtained 3 ways a. environmental systems must not be damaged beyond their ability to recover b. renewable resources must not be depleted faster than they can regenerate c. nonrenewable resources must be used sparingly