Ecology Exam 1 Terminology

Biotic

everything alive

Abiotic

everything that is not alive

Biosphere

layer of the Earth containing living organisms

individuals

living being, fundamental unit of ecology

species

a group of populations that are capable of inter-breeding and producing fertile offspring (reproductively isolated); Fundamental unit of microevolution

populations

a group of organisms belonging to the same species and occupying the same area at the same time; Fundamental unit of microevolution

Community

an assemblage of different populations within a given area

Biome

a community bounded by geography, and usually defined by a particular climax community

Ecosystem

a complex, self-sustaining natural system compromised by biotic and abiotic interactions.

Diversity

variation; either the number of species in a community, how different these species are, or their relative abundance

Competition (and competitive exclusion)

interactions among individuals and among different species for shared resources; restriction or elimination of one species from a habitat through monopolization of shared resources

pelagic

associated with the open ocean, a habitat without an solid barriers

coastal

associated with land adjacent to body of water

benthic

associated with the bottom of a body of water (typically marine)

estuary

coastal, brackish bodies of water open to both freshwater and marine ecosystems

Thermophilic

organisms living in high temperature environmemts

fluvial

pertaining to, or found in, rivers (i.e. riverine)

riparian

pertaining to, or found along riverbanks

lentic

still (not moving) bodies of water (ponds, swamps)

lotic

rapidly moving bodies of water (rivers and streams)

allochthonous

nutrients or materials imported into a habitat or system

autochthonous

nutrients or materials found locally within a habitat or system

headwaters

the origins of a river or stream, always ‘upstream’

osmoregulation

maintenace of osmotic pressure in organisms through control of salts and water

hyperosmotic

increased relative osmotic pressure (within an animal)

hypoosmotic

decreased relative osmotic pressure (within an animal)

boundary layer

thin layer of fluid surrounding a submerged object

anaerobic/anoxic

state of, or processes occuring in, the absence of oxygen

homeotherms

organisms that maintain constant internal temperature

poikilotherms

organisms that have varying internal temperature

ectotherms

organisms with body temperature regulated by external temperature

endotherms

organisms which make enough metabolic heat to raise body temperature

weather

short term state of the atmosphere at a specific time and place, including the temperature, humidity, cloud cover, precipitation, wind, etc.

climate/climatic

long-term, typical atmospheric conditions in an area, such as temperature and rainfall

tropics

regions of Earth that lie between the latitude lines of the Tropic of Cancer and the Tropic of Capricorn

temperate

between the tropics and the polar regions, mild to warm summers and cool to cold winters

polar

situated at or around either of Earth’s poles, climate featuring cool summers and very cold winters

arid/xeric

a lack of water availability, generally due to low precipitation. Xeric refers to low water availability

elevation

changes in sea level or altitude (elevation)

topography

form of the landscape—its steepness, shape, and slope aspect (slope direction)

sympatry vs allopatry

speciation in the same region, without barriers vs. speciation through a barrier (usually geological)

barriers

obstruction to gene flow or organism migration

transect

an artificial line across an expanse of ground along which ecological measurements are taken, continuously or at regular intervals

disturbed/distrubance

physical force, agent, or process, either abiotic or biotic, causing a perturbation to an ecological system

groundwater

water that collects or flows beneath the earth's surface, percolating through and filling the porous spaces in soil

transpiration

evaporation of water from leaves while their stomata are open (for the passage of CO2 and O2 during photosynthesis).

C3 vs C4 vs CAM

different means of performing photosynthesis, C4 & CAM spatially or temporally break-up photosynthetic intermediate stages. C4 and CAM plants are adapted for arid or xeric environments, where water is limited.

thermal inertia

the ability of a material to conduct and store heat, its resistance to changing temperature

thermoregulation

mechanism by which organisms maintain body temperature as part of homeostasis

homeotherm (endotherm)/ poikilotherm (ectotherm)

maintaining (or not) a relatively uniform body temperature nearly independent of the environment

littoral

the shallow area at the edge of a lake or pond containing rooted vegetation (e.g., lilies, reeds)

limnetic (FW pelagic)

open water past the littoral zone, where phytoplankton, not rooted plants, are the primary producers

profundal

deepest waters of the lake where light does not reach, usually hypoxic or even anoxic

thermocline

transition layer between two layers of water, usually warmer in upper, mixed layers and cooler below

stratification

tendency of lakes to form separate and distinct thermal layers during warm weather

watershed

the land area that channels rainfall and snowmelt to creeks, streams, and rivers

wetlands

land that is either covered by water or saturated with water, permanently or seasonally, and is shallow enough for emergent vegetation at all depths

salt marshes

a type of coastal wetland, dominated by grasses, that is regularly flooded by seawater

mangrove swamps/mangal

a tidal, marine swamp that is dominated by emergent, woody mangroves

intertidal (rocky or sandy)

coastal seashore which is covered at high tide and uncovered at low tide

coral reefs

living & non-living structures in shallow oceans that are formed by corals and their calcareous skeletons

neritic zone

shallow part of an ocean immediately adjacent to the coast, i.e., the inundated continental shelf

ocean zone

ocean region beyond the coasts and continental shelf

photic zone

uppermost layer of a body of water where enough light penetrates to permit photosynthesis

aphotic zone

region of a body of water, beneath the photic zone, where no light penetrates

biomass

quantity of organic material that comes from plants and animals

growing season

portion of the year during which rainfall, temperature & daylight) permit plant growth •

soil

material on the immediate surface of Earth which plants grow in

parent material

the geologic material from which soil horizons form

angiosperms

flowering plants

coniferous

‘evergreens,’ cone-bearing seed plants, a subset of gymnosperms

deciduous (plants)

plants, usually trees, that lose their leaves at the end of their growing season

sclerophyllous

evergreen trees and shrubs with hard, thick, leathery, and usually small leaves

herbaceous

any vascular plant that does not have true woody tissues (e.g., ferns & grasses)

Diversification

speciation minus extinction = diversification

habitat complexity

heterogeneity in the arrangement of physical structures in habitats

phylogenetics

study of the evolutionary history and relationships among groups of organisms

pollination

transference of pollen grains from the male anther of a flower to the female stigma

niche

range of biotic and abiotic conditions an organism can tolerate

fundamental niche

range of biotic and abiotic conditions an animal can persist in

realized niche

range of biotic and abiotic conditions an organisms persists in, after accounting for competition

geographic range

measure of the total area covered by a population

coexistance

ability of species to persist together indefinitely in the absence of any major change

intraspecfic

occurring within a species (one species)

interspecfic

\- occurring between species (at least two species)

performance

organism's ability to execute dynamic and ecologically relevant tasks (catch prey, locomote, display for mates, etc.)

fitness

organism's ability to pass its genetic material to its offspring (reproductive success), a reflection of the investment it can make in reproduction

niche partitioning

mechanisms by which co-occurring competitors may coexist through division of resources

fecundity

maximum potential reproductive output of an individual

intraspecific competition

maximum potential reproductive output of an individual

interspecific competition

competition occurring between two or more species

resource

anything an organism consumes or uses

renewable resources

resources that are constantly regenerated

Liebig’s law of the minimum

a population increases until the supply of the most limited resource prevents further increase

carrying capacity

the maximum number of individuals of a species that the environment can carry and sustain

competition coefficients

variables that convert between number of one species and the number of a competing species

zero population growth isocline

population sizes at which a population experiences zero net growth (birth rates = death rates)

exploitative competition

individuals consume and reduce a resource to an extent that other individuals cannot persist

interference competition

when competitors do not (immediately) consume resources but guard them from others

allelopathy

a type of interference that occurs when organisms use chemicals to harm competitors