2.2-2.3 Communites and Ecosystem Flashcards
(29 cards)
Respiration
The process where organisms convert glucose and oxygen into energy (ATP), releasing carbon dioxide and water.
Photosynthesis
The process where plants convert sunlight, carbon dioxide, and water into glucose and oxygen.
Chemosynthesis
The production of organic compounds using energy from chemical reactions instead of sunlight, typically in deep-sea ecosystems.
Food web
A complex network of interconnected food chains showing energy flow in an ecosystem.
Ecological
pyramid
A graphical representation of relationships between trophic levels
Biomass
The total mass of living organisms in a given area or trophic level, usually measured as dry weight per unit area (e.g., g/m²).
Examples of consumers
Organisms that obtain energy by eating other organisms. Examples:
Primary consumers (herbivores) – deer, rabbits.
Secondary consumers (carnivores/omnivores) – foxes, frogs.
Tertiary consumers (top predators) – eagles, sharks.
Trophic Levels
The hierarchical levels in a food chain/web based on energy transfer. Example: Producers → Primary Consumers → Secondary Consumers → Tertiary Consumers.
Primary productivity
The rate at which producers convert solar or chemical energy into organic substances.
Secondary productivity
The rate at which consumers convert ingested food into biomass
Sustainble yield
The rate at which a natural resource (e.g., fish, timber) can be harvested without depleting the stock, ensuring long-term availability.
Ecological Efficiency
Ecological Efficiency=(energy used for growth(new biomass)/energy suplied)x100
Nitrogen Cycle
The biogeochemical cycle where nitrogen is converted between different forms (e.g., nitrogen fixation, nitrification, denitrification) to support life.
Carbon Cycle
The movement of carbon through the biosphere, atmosphere, oceans, and geosphere, involving processes like respiration, photosynthesis, combustion, and decomposition.
Pyramid of biomass
A diagram showing the total biomass at each trophic level in an ecosystem.
Pyramid of Productivity
A diagram showing the energy flow and loss at each trophic level over time, typically measured in kJ/m²/year.
Carbon Cycle Process
1️⃣ Main Carbon Stores: Atmosphere, oceans, fossil fuels, soil, and living organisms.
2️⃣ Key Processes: Photosynthesis (absorbs CO₂), respiration (releases CO₂), combustion (burning fossil fuels), decomposition (releases CO₂).
3️⃣ Human Impact: Deforestation and burning fossil fuels increase atmospheric CO₂, contributing to climate change.
Nitrogen Cycle Process
1️⃣ Main Nitrogen Stores: Atmosphere (78% nitrogen gas), soil, water, living organisms.
2️⃣ Key Processes:
Nitrogen Fixation: Bacteria convert N₂ into ammonia (NH₃) or nitrate (NO₃⁻) for plants.
Nitrification: Ammonia is converted into nitrites (NO₂⁻) and then nitrates (NO₃⁻).
Assimilation: Plants absorb nitrates to make proteins.
Denitrification: Bacteria convert nitrates back into nitrogen gas (N₂), releasing it into the atmosphere.
3️⃣ Human Impact: Excessive fertilizer use leads to eutrophication (algal blooms that deplete oxygen in water).
Stores
A place where matter or energy is accumulated and held for a period of time. Example: The ocean is a major carbon store.
Sink
A store that absorbs more of a substance than it releases. Example: Forests act as a carbon sink by absorbing CO₂ through photosynthesis.
Source
A process or area that releases more of a substance than it absorbs. Example: Burning fossil fuels is a carbon source, releasing CO₂ into the atmosphere.
natural capital
The world’s natural resources that provide goods and services useful to humans.
Examples: Forests (timber), water (drinking supply), soil (agriculture), fossil fuels.
natural income
The renewable yield (resources or services) produced by natural capital over time.
Example: Trees regrowing in a forest, fish stocks replenishing in an ocean.
atmospheric system
➡ The Earth’s atmosphere is a complex system that controls climate, weather, and heat balance.
