AICE Environmental Management: Ecosystems and Biomes

A comprehensive collection of 100 vocabulary flashcards covering ecosystems, cellular metabolic processes, trophic interactions, ecological pyramids, and the climate, productivity, adaptations, and human impacts of the major terrestrial biomes.

Ecosystem

The interaction between living (biotic) organisms and their non-living physical environment (abiotic components).

Biome

A large-scale, global ecosystem (climax community) characterized by distinctive vegetation, soil type, climate, and wildlife.

Climate

The long-term average conditions of precipitation and temperature in a region, influenced by latitude, geography, and wind or ocean currents.

Species

A group of morphologically and genetically similar organisms capable of interbreeding to produce fertile offspring.

Population

A group of individuals belonging to the same species that interbreed and occupy the same geographic area at the same time.

Community

An interacting assemblage of many different populations of species inhabiting a common environment at the same time.

Habitat

The specific physical location or 'address' where an individual organism or an entire biological community lives.

Ecological Niche

The functional position of an organism within its environment, comprising its habitat, its temporal activity patterns, and the resources it obtains and provides.

Generalist Species

An adaptable organism possessing a broad ecological niche that can survive across diverse environmental conditions and utilize varied resources, such as a raccoon.

Specialist Species

An organism possessing a narrow ecological niche that is highly sensitive to environmental change and requires specific food or habitat conditions, such as a koala.

Interspecific Competition

The competition for limited resources that occurs between individuals of two or more different species with overlapping niches.

Intraspecific Competition

The competition for limited resources occurring between individuals belonging to the exact same species.

Resource Partitioning

The evolutionary specialization and division of limited resources among coexisting species that reduces niche overlap and minimizes direct interspecific competition.

Biodiversity

A measure of the total number and variety of living species present within a given geographical area.

Species Richness

The absolute count of different biological species inhabiting an ecological community or defined area.

Latitudinal Diversity Gradient

The biogeographical pattern in which species richness increases toward the equator due to abundant solar energy, heat, and humidity driving higher plant productivity.

Limiting Factor

Any biotic or abiotic environmental component that restricts the rate of a physiological process, population size, or geographic distribution of organisms.

Biotic Factors

The living biological components of an ecosystem that affect organisms, including producers, consumers, decomposers, competition, predation, grazing, parasitism, and disease.

Abiotic Factors

The non-living physical and chemical components of an ecosystem, such as temperature, humidity, water availability, oxygen, salinity, light, and pH.

Autotrophs (Producers)

Organisms that synthesise their own organic nutritional compounds from inorganic raw materials using light energy (photosynthesis) or chemical energy (chemosynthesis).

Chemosynthesis

The biological process by which certain specialized autotrophic bacteria, such as those inside hydrothermal vent tube worms, synthesise organic nutrients using chemical energy.

Photosynthesis

The physiological process by which plants and other autotrophs synthesise glucose and oxygen using carbon dioxide, water, and solar light energy.

Word Equation for Photosynthesis

$\text{carbon dioxide} + \text{water} \rightarrow \text{glucose} + \text{oxygen}$, driven by light energy absorbed by chlorophyll.

Chemical Equation for Photosynthesis

$6\text{CO}_2 + 6\text{H}_2\text{O} \rightarrow \text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2$.

Chloroplast

The plant cell organelle that houses chlorophyll pigments and serves as the cellular site for autotrophic nutrition and photosynthesis.

Chlorophyll

The specialized photosynthetic pigment embedded within chloroplasts that absorbs light energy (photons) to drive carbohydrate synthesis.

Solar (Light) Energy

The electromagnetic radiation energy captured in the form of photons that defines the process driving photosynthetic chemical reactions.

The Sun

The primary celestial body that acts as the ultimate external source of light energy for natural ecosystems.

Photon

A discrete quantum of light energy absorbed by antenna chlorophyll pigments and transferred to reaction center chlorophyll to trigger photosynthesis.

Aerobic Respiration

The metabolic process in cells that breaks down glucose molecules in the presence of oxygen to release usable chemical energy, water, carbon dioxide, and heat.

Word Equation for Aerobic Respiration

$\text{glucose} + \text{oxygen} \rightarrow \text{carbon dioxide} + \text{water}$, yielding cellular energy alongside metabolic heat loss.

Chemical Equation for Aerobic Respiration

$\text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 \rightarrow 6\text{CO}_2 + 6\text{H}_2\text{O}$.

Mitochondria

The double-membrane cellular organelles, known as the powerhouses of the cell, where aerobic respiration breaks down glucose to release energy.

Heterotrophs (Consumers)

Organisms that cannot manufacture their own food and must obtain organic matter and energy by consuming other organisms.

Herbivore

A primary consumer that feeds exclusively on autotrophic producers such as plants or algae.

Carnivore

A consumer that obtains energy and nutrients by preying on and consuming other animals.

Predator

An organism that actively hunts, captures, and kills other living animals for sustenance.

Prey

An organism that is hunted, killed, and eaten by a predator.

Scavenger

A consumer that feeds primarily on dead animal carcasses killed by other predators or natural causes, such as a hyena.

Omnivore

A versatile consumer that routinely feeds on both plant matter (producers) and animal matter (consumers).

Decomposer

An organism, primarily bacteria, fungi, worms, and certain insects, that breaks down dead organic material and metabolic wastes into simpler inorganic nutrients.

Food Chain

A linear sequence of feeding relationships illustrating the direct pathway of potential energy transfer from a primary producer through successive consumers.

Food Web

A complex network of interconnected food chains reflecting multiple feeding interactions and varying trophic levels among coexisting organisms.

Trophic Level

The hierarchical feeding level occupied by an organism within a food chain or ecological pyramid, numbered consecutively from producers upward.

Primary Consumer

An organism occupying the second trophic level ($2$) that feeds directly upon primary producers.

Secondary Consumer

An organism positioned at the third trophic level ($3$) that captures and eats primary consumers.

Tertiary Consumer

An organism positioned at the fourth trophic level ($4$) that consumes secondary consumers.

Quaternary Consumer (Apex Predator)

An organism situated at the top of a food chain or trophic level $5$ that experiences no natural predation in its ecosystem.

Ten Percent ($10\%$) Rule

The ecological principle that approximately $10\%$ of stored chemical energy is transferred from one trophic level to the next, while the remaining $90\%$ is lost.

Heat Loss in Food Chains

The dissipation of approximately $90\%$ of potential energy between trophic levels as metabolic heat through aerobic respiration, alongside non-transferable matter like teeth.

Trophic Cascade

A top-down ecological process wherein the activity or removal of a predator indirectly impacts the abundance and health of organisms across lower, non-adjacent trophic levels.

Aleutian Islands Trophic Cascade

The ecological shift where introduced Arctic foxes preyed on native seabirds, drastically reducing phosphorus-rich guano deposition and causing maritime grasslands to convert into tundra.

Boom and Bust Population Cycle

A cyclic population dynamic characterized by rapid exponential growth ('boom') followed by a dramatic crash ('bust'), seen regularly in arctic lemmings every $3-4\,\text{years}$.

"White Wilderness" Lemming Myth

A debunked narrative from a $1958$ Disney documentary claiming lemmings deliberately commit mass suicide, which was staged by filmmakers who pushed lemmings off a cliff.

Weak Associates

Species interactions in a food web where a predator feeds upon multiple alternative prey items, increasing the ecological resilience of the community.

Strong Associates

Trophic interactions where a predator relies almost entirely upon a single, specific prey species, making the relationship vulnerable to population crashes.

Unidirectional Energy Flow

The one-way trajectory of energy through the biosphere, originating from the sun, moving through trophic levels, and permanently exiting as radiated heat.

Biosphere Matter Cycling

The circular movement and biochemical recycling of physical elements through living organisms, soil, water, and the atmosphere.

Inorganic Nutrient Pool

The reservoir of abiotic mineral nutrients in soil and water replenished by decomposers and subsequently absorbed by autotrophic producers.

Ecological Pyramid

A graphical representation depicting the relative number of organisms, biomass, or energy flow across the successive trophic levels of an ecosystem.

Pyramid of Numbers

An ecological pyramid that quantifies and displays the total physical count of individual organisms residing at each successive trophic level.

Pyramid of Biomass

An ecological pyramid that calculates and displays the total dry mass of living organic material present at each successive trophic level.

Pyramid of Energy

An upright, broad-based graphical model representing total energy transfer and net productivity across trophic levels, following the $10\%$ efficiency rule.

Tropical Rainforest Pyramid Inversion

An ecological phenomenon where a pyramid of numbers has an inverted, narrow base because a small number of massive trees support huge numbers of primary consumer insects.

Climatogram (Climate Graph)

A dual-axis graph combining monthly precipitation represented by vertical bars (left axis) with average monthly temperature plotted as a continuous line (right axis).

Whittaker Biome Diagram

A two-dimensional graphical framework illustrating how terrestrial biome distributions correlate with gradients of mean annual precipitation and average temperature.

Tundra Biome

A cold, wind-swept, treeless biome located south of the Arctic ice caps characterized by long dark winters, low precipitation, and permanently frozen subsoil.

Permafrost

An impermeable layer of permanently frozen subsoil in polar and subpolar regions that impedes water drainage and prevents tree root penetration.

Tundra Net Primary Productivity

A very low net primary productivity of $140\,\text{g}\,\text{m}^{-2}\,\text{yr}^{-1}$ resulting from freezing temperatures, waterlogged shallow soils, and a growing season under $3\,\text{months}$.

Tundra Vegetation Adaptations

Morphological traits including low growth forms (heights $\le 1\,\text{meter}$) dominated by shallow-rooted mosses and lichens adapted to withstand extreme wind and shallow active soil layers.

Tundra Animal Adaptations

Physiological adaptations such as thick insulating fur coats, dense subcutaneous fat layers, and reduced ear sizes to minimize heat loss in freezing conditions.

Tundra Methane Feedback Loop

A positive climate feedback cycle where rising global temperatures melt arctic permafrost, releasing stored methane gas that traps more heat and accelerates further permafrost thaw.

Taiga (Boreal Forest)

A northern biome found exclusively in the Northern Hemisphere characterized by long, freezing winters, deep permafrost, and an average annual precipitation of $100\,\text{in/yr}$.

Coniferous Trees

Needle-bearing, evergreen cone-bearing trees that dominate the taiga, adapted to shed snow readily and retain water during harsh freezing winters.

Taiga Nutrient Storage

An ecosystem condition where most organic nutrients remain locked in the surface litter layer because freezing temperatures inhibit decomposer activity and slow soil mineralization.

Clearcutting in the Taiga

The commercial logging practice of cutting all trees in a designated area, which destroys habitats, increases erosion and flooding, and exposes underlying permafrost to melting.

Siberian Tiger Thermal Limitations

The physiological vulnerability of taiga carnivores whose heavy winter fur coats and thick body fat stores make them poorly adapted to warmer temperate temperatures.

Bark Beetle Infestation

An ecological disturbance where non-native or warming-expanded beetles bore into spruce bark to lay eggs, killing standing trees across thousands of hectares of taiga.

Temperate Forest

A populated biome with mild climates, four distinct seasons, freezing winters, and annual precipitation ranging from $500\,\text{mm}$ to $1500\,\text{mm}$.

Deciduous Trees

Broadleaf trees dominating temperate forests that shed their leaves annually before winter to conserve water and prevent frost damage.

Temperate Forest Productivity

The second highest terrestrial net primary productivity ($1200\,\text{g}\,\text{m}^{-2}\,\text{yr}^{-1}$), supported by deep, nutrient-rich soils and layered vertical canopy growth.

Primary (Old-Growth) Forest

Virgin forest ecosystems that have never been cleared or harvested by humans, representing only $1-2\%$ of remaining temperate forest land worldwide.

Secondary Forest

Forest communities that have naturally regenerated following major human-induced disturbances such as logging or agricultural abandonment.

Temperate Grassland

A flat, semi-arid biome featuring extreme temperature fluctuations ($> 100^\circ\text{F}$ in summer, $-40^\circ\text{F}$ in winter) and annual precipitation between $250\,\text{mm}$ and $1000\,\text{mm}$.

Temperate Grassland Soil Mat

A dense, nutrient-rich topsoil layer created when perennial grasses die back in the winter and decompose into a thick organic mat.

"World's Breadbasket"

A designation given to temperate grasslands because roughly $47\%$ of their fertile lands have been plowed and converted into grain agriculture.

Dust Bowl of the 1930s

A historic ecological disaster across North American prairies triggered by overgrazing and mechanical plowing, which pulverized dry topsoil and allowed wind to blow it away.

Black-Footed Ferret

A federally endangered prairie carnivore specialized in hunting burrowing prairie dogs within temperate grasslands.

Tropical Grassland (Savanna)

A warm biome characterized by consistently high year-round temperatures, very distinct wet and dry seasons, and periodic natural fires that maintain open grasslands.

Baobab Tree

A drought-resistant savanna tree featuring an immense swollen trunk adapted for water storage, thick spongy bark, and deciduous leaves that drop in the dry season.

Umbrella Thorn Acacia

A fire- and drought-resistant savanna tree that develops sharp physical thorns and deep taproots to defend against large herbivores and reach groundwater.

Savanna Ungulate Migration

The seasonal long-distance movement of grazing herds timed with the arrival of rainy periods to access green pasture and reproduce when forage is abundant.

Savanna Poaching Pressures

The illegal slaughter of large savanna herbivores, particularly elephants and rhinoceroses, targeted by poachers for ivory tusks and keratin horns.

Desertification

The degradation and aridification of semi-arid ecosystems into unproductive, desert-like conditions driven by poor agricultural practices, overgrazing, and climate change.

Tropical Rainforest

The most productive terrestrial biome, characterized by constant warm temperatures, high humidity, and high annual rainfall ($2000-5000\,\text{mm}$).

Tropical Rainforest Soil Dynamics

A condition where soils are thin, highly weathered, and nutrient-poor because dense vegetation absorbs dissolved mineral nutrients almost immediately upon decomposition.

Rainforest Canopy Stratification

The vertical resource partitioning of the rainforest into distinct tiers: Emergent ($200'+\text{ft}$), Canopy ($100-150'\text{ft}$), Understory ($50-100'\text{ft}$), and Forest Floor ($< 15'\text{ft}$).

Rafflesia kerrii (Corpse Flower)

A rare, endangered parasitic plant native to shady lowland rainforests of Indonesia that produces the largest single bloom of any flowering plant on Earth.

Rainforest Deforestation Threats

The clearance of tropical rainforests for commercial timber and cattle ranching, resulting in $34\%$ of original forest being cleared and another $30\%$ being degraded.

Desert Biome

An extremely dry biome located around $30^\circ\text{N}$ and $30^\circ\text{S}$ of the equator that covers $20-30\%$ of Earth's land and receives less than $250\,\text{mm}$ of rain per year.