Ecology, Biogeochemical Cycles, and Human Impact Vocabulary

Comprehensive vocabulary review flashcards covering ecological levels of organization, biotic/abiotic factors, energy flow, food webs, biogeochemical cycles, and human impacts on ecosystems.

Biotic Factors

The living or once-living parts of an ecosystem, such as plants, animals, fungi, and bacteria.

Abiotic Factors

The nonliving physical and chemical parts of an ecosystem, such as sunlight, water, soil, rocks, air, and temperature.

Species

A group of organisms that can reproduce together.

Organism

One individual living thing.

Population

Members of the same species living in one specific area.

Community

All the different populations of organisms living together in one area.

Ecosystem

A system formed by the interaction of biotic and abiotic factors in an area.

Biosphere

All ecosystems on Earth combined, encompassing the atmosphere (air), hydrosphere (water), and lithosphere (earth).

Autotrophs (Producers)

Organisms that make their own food using sunlight through photosynthesis or chemical energy through chemosynthesis.

Heterotrophs (Consumers)

Organisms that eat other organisms to obtain energy.

Decomposers

Organisms, such as fungi and bacteria, that break down dead organisms and recycle nutrients back into the ecosystem.

Food Chain

A linear sequence showing one pathway of energy flow through organisms.

Food Web

A network showing many interconnected food chains within an ecosystem.

Trophic Level

Each distinct step or level in a food chain or energy pyramid.

10% Energy Transfer Rule

The principle that only about $10\%$ of stored energy in one trophic level is passed on to the next level, while the remainder is used for life processes or lost as heat.

Predator

An organism that hunts and kills other organisms for food.

Prey

An organism that is hunted and eaten by another organism.

Herbivore

A consumer that eats plants only.

Carnivore

A consumer that eats other animals only.

Omnivore

A consumer that eats both plants and animals.

Scavenger

An animal that feeds on dead animals killed by other species or natural causes.

Apex Predator

A top predator in a food chain or web with few or no natural predators.

Photosynthesis (Carbon Cycle)

The process where plants and algae remove carbon dioxide from the atmosphere to produce sugars using sunlight.

Cellular Respiration (Carbon Cycle)

The process in which animals and plants use energy and return carbon dioxide to the atmosphere.

Decomposition (Carbon Cycle)

The process in which fungi and bacteria recycle carbon and other nutrients from dead organisms.

Fossilization

The geological process occurring over millions of years where dead plants and animals form fossil fuels under specific conditions.

Combustion

The burning of fossil fuels, which releases carbon dioxide into the atmosphere.

Evaporation

The process where liquid water is heated by the sun and converts into gas or steam.

Transpiration

The process where water vapor is released from plant leaves into the atmosphere via tiny openings called stomata.

Condensation

The process where water vapor cools at higher altitudes and transforms into liquid water droplets, forming clouds.

Precipitation

The process that returns water to the surface of the Earth in the form of rain, snow, sleet, or hail.

Percolation

The movement of water downward through soil layers toward lakes, rivers, or aquifers.

Nitrogen Fixation

The conversion of atmospheric nitrogen gas into ammonium ions ($\text{NH}_4^+$) by soil bacteria or lightning.

Nitrification

A two-step bacterial process where nitrifying bacteria convert ammonium into nitrites, and another group converts nitrites into nitrates ($\text{NO}_3^-$).

Assimilation (Nitrogen Cycle)

The absorption of nitrates from the soil by plant roots to construct proteins and nucleic acids, which are then passed to animals via feeding.

Ammonification

The process where decomposers convert nitrogen compounds from dead organisms and animal waste into ammonium ($\text{NH}_4^+$).

Denitrification

The process where denitrifying bacteria convert nitrates in the soil back into nitrogen gas for the atmosphere.

Weathering

The physical erosion and chemical breakdown of rocks that releases stored phosphates into soil and water.

Sedimentation

The accumulation and compaction of dead marine organisms over thousands of years to form sedimentary rock.

Uplift

A geological process that brings aquatic sedimentary rocks back onto terrestrial land.

Renewable Resources

Natural resources that naturally replenish themselves over time faster than they are consumed, such as solar, wind, water, and plant biomass.

Non-Renewable Resources

Natural resources that are consumed much faster than they can form, such as oil, coal, natural gas, and nuclear energy.

Invasive Species

Non-native species introduced into an ecosystem that outcompete native organisms and disrupt existing food webs.

Enhanced Greenhouse Effect

The intensification of heat trapping in the troposphere due to elevated levels of greenhouse gases released from human activity such as burning fossil fuels.

Ocean Acidification

The reduction of ocean pH caused by excess atmospheric carbon dioxide dissolving in seawater to form carbonic acid.

Eutrophication

An ecological process where excess fertilizer runoff triggers rapid algal growth, followed by algal death and oxygen depletion by decomposers, resulting in aquatic dead zones.

Bioaccumulation

The gradual buildup of harmful chemicals inside a single individual organism over time.

Biomagnification

The process where toxin concentrations increase at higher trophic levels, resulting in the highest concentrations in top predators.

Wildlife Corridors

Structures or tracts of habitat designed to connect fragmented natural areas, allowing animals to travel safely.

Reforestation

The planting of trees to restore destroyed or degraded forests, which boosts biodiversity and enhances carbon storage.