Unit 1 Introduction to Environmental Science

Unit 1: Introduction to Environmental Science 1. The Scientific Method: ○ A systematic approach to problem-solving that involves observations, forming hypotheses, experiments, and drawing conclusions. ○ Steps: Observation → Hypothesis → Experiment → Conclusion. 2. Description vs. Hypothesis-based Science: ○ Descriptive Science: Observes and describes phenomena (e.g., cataloging species). ○ Hypothesis-based Science: Involves testing a hypothesis through experiments and observations. 3. Basic vs Applied Science: ○ Basic Science: Focuses on gaining knowledge for the sake of knowledge (e.g., fundamental research). ○ Applied Science: Focuses on using scientific knowledge to solve practical problems (e.g., developing technology). 4. Deductive vs Inductive Reasoning: ○ Deductive: Starts with a general theory and tests it with specific observations (top-down approach). ○ Inductive: Starts with specific observations and develops a general theory (bottom-up approach). 5. Control and Experimental Variables: ○ Control Variables: Factors kept constant during an experiment. ○ Experimental Variables: Factors that are changed or manipulated to test the hypothesis. 6. Frontier Ethic, Sustainability Ethic, and Land Ethic: ○ Frontier Ethic: Emphasizes human dominance over nature (often associated with exploitation of resources). ○ Sustainability Ethic: Focuses on using resources in a way that ensures they are available for future generations. ○ Land Ethic: A philosophy advocating for the preservation of natural ecosystems, promoting respect and stewardship. 7. Recent Environmental Impact of Human Activity: ○ Human activities like deforestation, pollution, overfishing, and climate change have significant impacts on ecosystems and biodiversity. 8. Purpose of Fishbone Diagrams: ○ Used to identify the root causes of a problem by breaking down potential causes in a visual format (also known as Ishikawa diagrams). 9. Ecological Footprint: ○ Measures the amount of land and resources required to support a person, community, or organization’s activities. 10. Indicators of Environmental Stress: ● Examples: Loss of biodiversity, changes in species populations, pollution levels, deforestation, and climate change impacts. 11. Definition of Environment, Habitat, and (Unspecified Term): ● Environment: The surroundings or conditions in which an organism lives. ● Habitat: The natural home or environment of an organism. ● Look up additional definitions or terminology from your textbook to clarify the missing term. Unit 2: Ecology and Ecosystems 1. The Food Chain: ○ Describes the flow of energy through different levels of organisms (producers → consumers → decomposers). 2. Biomagnification: ○ The process where toxins or pollutants become more concentrated as they move up the food chain. 3. Biogeochemical Cycles: ○ Water Cycle: Movement of water through evaporation, condensation, and precipitation. ○ Nitrogen Cycle: The movement of nitrogen through ecosystems, involving processes like nitrogen fixation and denitrification. ○ Carbon Cycle: The flow of carbon through living organisms, the atmosphere, oceans, and earth. 4. Chaparral Systems: ○ Ecosystems characterized by hot, dry summers and mild, wet winters; typically found in Mediterranean regions. 5. Aphotic Zones (Biomes): ○ Aphotic Zone: Deep ocean layers where light does not penetrate. ○ Could be linked to biomes like deep-sea ecosystems. 6. Population and Population Growth Models: ○ Exponential Growth: Rapid, unchecked growth in an ideal environment. ○ Logistic Growth: Growth that slows as the population reaches carrying capacity. 7. Survivorship Curve: ○ Graphs the number of individuals surviving at each age for a given species. ○ Types: Type I (most survive to old age), Type II (constant mortality rate), Type III (many die young). 8. Carrying Capacity: ○ The maximum number of individuals of a species that an environment can support without degrading the environment. 9. K vs R-selected Species: ○ K-selected: Species that produce few offspring, invest in their survival (e.g., humans, elephants). ○ R-selected: Species that produce many offspring, but invest little in their survival (e.g., insects, fish). 10. Competitive Exclusion Principle: ● States that two species competing for the same resources cannot coexist indefinitely; one will be driven to extinction. 11. Mimicry: ● One species evolves to resemble another species, often for protection (e.g., a non-poisonous species resembling a poisonous one). 12. Inter-species Relationships: ● Mutualism: Both species benefit (e.g., bees pollinating flowers). ● Parasitism: One species benefits at the expense of the other (e.g., ticks on mammals). ● Commensalism: One species benefits, the other is unaffected (e.g., barnacles on whales). 13. Biodiversity: ● The variety of life in all its forms, levels, and combinations (species, genetic, and ecosystem diversity). Unit 3: Urbanization and Sustainability 1. Urban Sprawl and Its Environmental Impacts: ○ Urban sprawl refers to the spread of cities into rural areas, leading to habitat loss, pollution, and increased energy consumption. 2. Highway Revenue Act and Highway Trust Fund: ○ Government programs that fund the construction and maintenance of highways, contributing to urban sprawl. 3. Urban Blight: ○ The decay of urban areas due to factors like economic downturn, neglect, and lack of investment. 4. Factors Needed for a Sustainable Community or City: ○ Efficient resource use, renewable energy sources, green infrastructure, waste management, and social equity. 5. Water Management: ○ Techniques for managing water resources, including conservation, distribution, and treatment. 6. Urban Agriculture: ○ The practice of growing food in urban areas to reduce transportation costs and improve food security. 7. LEED (Leadership in Energy and Environmental Design): ○ A certification program that recognizes environmentally sustainable buildings and construction practices. 8. Main Sources of Electrical Power: ○ Be familiar with the main sources: natural gas, coal, nuclear, hydroelectric, and renewable resources (wind, solar). Unit 4: Water Resources 1. Facts Associated with World’s Water Supply: ○ Most water is saline (97%), with only 3% being freshwater (of which about 70% is frozen in glaciers). 2. Terminology Associated with Water Sources: ○ Tributary: A smaller stream or river that feeds into a larger one. ○ River Discharge: The volume of water flowing through a river. ○ Drainage Basin/Watershed: Area of land drained by a river and its tributaries. 3. Facts Associated with Water Usage: ○ Agriculture uses the most water, followed by industrial uses, and then domestic consumption. 4. Impacts of Large Water Use on Groundwater: ○ Overuse of groundwater can lead to depletion, subsidence (land sinking), and contamination. 5. Water Stress: ○ Occurs when the demand for water exceeds the available supply in a region. 6. Units of Concentration: ○ Examples: ppm (parts per million), ppb (parts per billion), mg/L (milligrams per liter). 7. Sources and Types of Water Pollution: ○ Point Source: Pollution from a single identifiable source (e.g., factory discharge). ○ Non-point Source: Pollution from diffuse sources (e.g., agricultural runoff). 8. Nutrient Overload: ○ Excess nutrients (like nitrogen and phosphorus) in water bodies lead to algal blooms and eutrophication. 9. Deepwater Horizon and Exxon Valdez Oil Spills: ○ Major environmental disasters involving the release of oil into oceans, causing long-term ecological damage. 10. Water Treatment Process: ● Involves filtration, chemical treatment, and sometimes disinfection (e.g., chlorination) to make water safe for consumption. 11. Hydrologic Cycle: ● The movement of water through evaporation, condensation, precipitation, and runoff, connecting Earth's water supply.