chapter 9-12
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** Chapter 9: Marine Ecosystems – Coral Reefs and Beaches**
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** Reef Structure (like layers of a cake)**
* **Reef Flat to Reef Crest**: This is where sand and rubble fill in the gaps of the coral framework.
* **Reef Crest (intertidal)**: Right at the water surface — wave energy is strong here. Living coral builds upward.
* **Surge Channels/Tunnels**: Pathways for water to rush in and out. Help circulate nutrients.
* **Reef Front and Beyond**: Coral growth slows as light decreases. Coral stops growing around **120 meters deep**.
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** Key Concepts**
* **Coral + Zooxanthellae**: Coral polyps live with algae (zooxanthellae) inside their tissues. The algae do photosynthesis and feed the coral, while the coral gives shelter and nutrients back.
* **Herbivores & Algae**: Fish like parrotfish eat algae so they don’t smother coral. Without them, algae would take over.
* **Ciguatera Poisoning**: Toxins from algae build up in fish — the higher up the food chain you eat, the more poison there is (biological magnification).
* **Coral Bleaching**: When water gets too warm, coral kicks out zooxanthellae. It turns white and becomes weak.
* **Managing Reefs**: Treat them like renewable resources — protect them, let them recover, and limit damage.
* **Global Warming Threats**: Warmer waters and acidic oceans stress and weaken coral reefs worldwide.
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** Key Terms**
* **Biological Magnification**: The process by which toxins (like ciguatera) become more concentrated in organisms at higher trophic levels in a food chain.
* **Ciguatera**: A type of food poisoning caused by eating fish that have accumulated toxins produced by certain microalgae (dinoflagellates), often found in tropical reefs.
* **Coral Bleaching**: The process where corals expel their symbiotic algae (zooxanthellae) due to stress (e.g., increased water temperature), causing the coral to turn white and often leading to coral death if conditions persist.
* **Coral Reef**: An underwater ecosystem characterized by corals that build massive limestone structures, providing habitat for diverse marine life.
* **Ecotourism**: Responsible travel to natural areas that conserves the environment and improves the well-being of local people.
* **Eutrophication**: The excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen.
* **Larvae**: The immature form of an animal that undergoes metamorphosis (e.g., coral larvae are free-swimming before settling).
* **Limestone**: A sedimentary rock composed primarily of calcium carbonate, which is the main material that corals use to build their skeletons and reef structures.
* **Ocean Acidification**: The ongoing decrease in the pH of the Earth's oceans, caused by the uptake of atmospheric carbon dioxide () from human activity.
* **Renewable Resource**: A natural resource that can be replenished naturally over time, such as sunlight, wind, or a properly managed coral reef.
* **Zooxanthellae**: Symbiotic dinoflagellates (algae) that live within the tissues of stony corals and other marine invertebrates, providing their hosts with nutrients through photosynthesis.
* **Photic/Aphotic Zone**:
* **Photic Zone**: The upper layer of a body of water that receives sunlight, allowing photosynthesis to occur.
* **Aphotic Zone**: The lower layer of a body of water that receives little to no sunlight.
* **Competition**: The struggle between organisms for limited resources (e.g., space, food, light).
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** Chapter 10: Ecosystem Changes**
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** Biological Control Agents**
* These are natural enemies (like bugs or viruses) used to control pest species instead of using harmful chemicals.
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** Key Concepts**
* **Introduced Species**: Animals or plants brought by humans to islands can become pests because there are no predators to control them.
* **Good Biological Control**: Should **only** target the pest — not harm native species.
* **Integrated Pest Management (IPM)**: Use the safest method first (like traps or barriers), only use pesticides if you really have to.
* **Species Extinction**: Caused by habitat loss, pollution, invasive species, and climate change.
* **Sewage Treatment**: Stops diseases from spreading and protects coral reefs.
* **Landfills + Recycling**: Recycling and shipping toxic waste off-island helps reduce pollution and saves space.
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** Key Terms**
* **Biodiversity**: The variety of life in the world or in a particular habitat or ecosystem.
* **Biological Control**: The method of controlling pests (such as insects, weeds, or diseases) using other living organisms.
* **Critical Habitat**: A specific area that contains features essential for the conservation of an endangered or threatened species and that may require special management and protection.
* **Endangered Species**: A species whose numbers are so small that it is at risk of extinction.
* **Eutrophication**: (See Chapter 9 Key Terms) The excessive richness of nutrients in a body of water, leading to dense plant growth and depletion of oxygen.
* **Extinct**: No longer existing; a species that has died out completely.
* **Habitat**: The natural home or environment of an animal, plant, or other organism.
* **Indicator Bacteria**: Types of bacteria (e.g., *E. coli*) whose presence in water indicates possible contamination by fecal matter, suggesting the potential presence of disease-causing pathogens.
* **Integrated Pest Management (IPM)**: An ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.
* **Introduced Species**: (See Chapter 10 Key Concepts) A species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental.
* **Mass Extinctions**: Events in Earth's history when a large percentage of all species become extinct in a relatively short period of time.
* **Pests**: Organisms that are troublesome or destructive to crops, livestock, or humans.
* **Pollution**: The presence in or introduction into the environment of a substance or thing that has harmful or poisonous effects.
* **Primary/Secondary Sewage Treatment**:
* **Primary Sewage Treatment**: A physical process that removes large solids and suspended particles from wastewater through screens and settling tanks.
* **Secondary Sewage Treatment**: A biological process that removes dissolved organic matter from wastewater, typically using microbes to break down pollutants.
* **Recycling**: The process of converting waste materials into new materials and objects.
* **Sanitary Landfill**: A site for disposing of waste materials by burial, designed to minimize environmental hazards by limiting leachate and gas production.
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** Chapter 11: Climate Change**
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** Key Concepts**
* **Greenhouse Effect**: Gases trap heat like a blanket around the Earth. It’s natural, but humans are making it stronger.
* **Greenhouse Gases**: , methane, and water vapor are the main ones. Most come from burning fossil fuels and cutting trees.
* **El Niño & Islands**: Causes weather changes like droughts or storms. Combined with global warming, it’s worse for small islands.
* **Global Warming Risks**: Rising seas, coral bleaching, extreme weather — especially dangerous for Pacific Islands.
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** Key Terms**
* **El Niño/Southern Oscillation (ENSO)**: A recurring climate pattern involving changes in the temperature of surface waters in the equatorial Pacific Ocean and the accompanying shifts in atmospheric pressure, affecting weather worldwide.
* **Fossil Fuels**: Natural fuels (e.g., coal, oil, natural gas) formed in the geological past from the remains of living organisms.
* **Global Warming**: A long-term increase in Earth's average surface temperature due to the buildup of greenhouse gases in the atmosphere, primarily from human activities.
* **Greenhouse Gases**: (See Chapter 11 Key Concepts) Atmospheric gases that absorb and emit radiation within the thermal infrared range, trapping heat in the Earth's atmosphere, such as carbon dioxide (), methane (), and water vapor ().
* **Ocean Acidification**: (See Chapter 9 Key Terms) The ongoing decrease in the pH of the Earth's oceans, caused by the uptake of atmospheric carbon dioxide () from human activity.
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** Chapter 12: Ecosystem Management & Sustainability**
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** Key Concepts**
* **Renewable vs. Nonrenewable**: Sun, wind, and rain are renewable. Fossil fuels and groundwater (if overused) are nonrenewable.
* **Sustainable Farming**: Avoid monoculture (planting one crop), use permaculture (working with nature), and protect soil and water.
* **Water Management**: Collect rain (catchment), protect aquifers, reduce pollution.
* **Renewable Energy on Islands**: Solar, wind, wave, and biofuels — all being tested to reduce reliance on imports.
* **Valuing Nature**: Putting a price on ecosystem services (like clean water or air) helps convince people to protect nature.
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** Key Terms**
* **Agroforestry**: A land-use system that integrates trees and shrubs with crops or livestock, providing economic, environmental, and social benefits.
* **Aquifer**: An underground layer of permeable rock, sand, or gravel that contains and transmits groundwater.
* **Brackish Water**: Water that has more salinity than fresh water, but not as much as seawater; often found in estuaries where rivers meet the sea.
* **Catchment**: An area that collects and drains rainwater into a particular body of water or system.
* **Ecosystem Services**: The many and varied benefits that humans freely gain from the natural environment and from properly functioning ecosystems (e.g., clean air and water, pollination, climate regulation).
* **Evaporation**: The process by which water changes from a liquid to a gas or vapor.
* **Fossil Fuel**: (See Chapter 11 Key Terms) Natural fuels (e.g., coal, oil, natural gas) formed in the geological past from the remains of living organisms.
* **Groundwater**: Water held underground in the soil or in pores and crevices in rock.
* **Hydrologic Cycle**: The continuous movement of water on, above, and below the surface of the Earth (also known as the water cycle).
* **Monoculture**: The agricultural practice of growing a single crop, plant, or livestock species, variety, or breed in a field or farming system at a time.
* **Permaculture**: An agricultural system or method that seeks to integrate human activity with natural surroundings to ensure long-term sustainability.
* **Recycling**: (See Chapter 10 Key Terms) The process of converting waste materials into new materials and objects.
* **Renewable/Nonrenewable Resources**:
* **Renewable Resource**: (See Chapter 9 Key Terms) A natural resource that can be regenerated or naturally replenished over time.
* **Nonrenewable Resource**: A natural resource that is present in finite quantities and cannot be replenished on a human timescale (e.g., fossil fuels, certain minerals).
* **Sustainability**: The ability to meet the needs of the present without compromising the ability of future generations to meet their own needs, often referring to environmental, social, and economic aspects.
* **Tragedy of the Commons**: An economic problem in which every individual tries to reap the greatest benefit from a given resource. As demand for the resource overwhelms the supply, every individual who consumes an additional unit directly harms others who can no longer enjoy the benefits.
* **Valuation**: The process of estimating the monetary worth of something, often applied to natural resources or ecosystem services to aid in management decisions.