Ecosystems and Energy Flow Flashcards

Vocabulary-style flashcards covering the fundamental concepts of ecosystem ecology, energy transfer, productivity, and biogeochemical cycles based on the lecture transcript.

Ecosystem

A community of living organisms and their interactions with their abiotic (nonliving) environment.

Equilibrium

The steady state of an ecosystem where organisms are in balance with their environment and each other.

Resistance

The ability of an ecosystem to remain at equilibrium in spite of disturbances.

Resilience

The speed at which an ecosystem recovers equilibrium after being disturbed.

Food Chain

A linear sequence of organisms through which nutrients and energy pass, including primary producers, primary consumers, and higher-level consumers.

Trophic Level

The specific position an organism occupies in a food chain or food web.

Primary Producers

Organisms at the bottom of the food chain that acquire energy through photosynthesis or chemosynthesis.

Secondary Consumers

Carnivores that eat the primary consumers.

Apex Consumers

Organisms at the very top of the food chain.

Food Web

A holistic non-linear model that more accurately represents ecosystem structure and dynamics than a food chain.

Photoautotrophs

Organisms such as plants, algae, and photosynthetic bacteria that harness solar energy and convert it to chemical energy in the form of ATP.

Chemoautotrophs

Primarily bacteria found in rare ecosystems without sunlight that use inorganic molecules like hydrogen sulfide ($H_2S$) as a source of chemical energy.

2nd Law of Thermodynamics

States that energy conversion is not 100% efficient, and some energy is lost as heat at each step, causing entropy to increase.

Biomass

The total mass of organisms in a given area at a particular trophic level.

Gross Primary Productivity (GPP)

The rate at which photosynthetic primary producers incorporate energy from the sun, or the total amount of chemical energy stored by producers.

Net Primary Productivity (NPP)

The energy that remains in primary producers after accounting for respiration and heat loss, calculated as $\text{NPP} = ext{GPP} - ext{Respiration}$.

Ecological Pyramids

Visualizations showing the relative amounts of parameters like organism numbers, energy, and biomass across trophic levels.

Biomagnification

The build-up of toxins, such as DDT, mercury, or arsenic, in a food chain where the concentration increases at higher trophic levels.

Silent Spring

A 1962 book by biologist Rachel Carson that discussed the detrimental effects of DDT on birds and ecosystems, sparking the modern environmental movement.

Biogeochemical Cycle

Also called nutrient cycling, it is the recycling of inorganic matter between living organisms and their environment.

Hydrosphere

The area of the Earth where water movement and storage occurs, including oceans, groundwater, and ice caps.

Transpiration

The process where liquid water is absorbed by plant roots, moves through the vascular system, and evaporates off the leaves.

Sublimation

The process where water changes state directly from a solid (ice) to a vapor.

Non-renewable Resource

A resource, such as fossil fuels, that is either regenerated very slowly or not at all, whose use exceeds its rate of formation.

Eutrophication

A process where excess nutrients from fertilizer runoff cause algal blooms, leading to light reduction and eventual oxygen depletion in water bodies.

Dead Zones

Coastal areas where phosphorus and nitrogen from fertilizers cause excessive microorganism growth that depletes oxygen and kills fauna.