TOPIC 2 Flashcards
Non-motile
Organism that does not move
Quadrat
A square with a defined (but variable) size that can be used to sample an area.
Estimating energy
Find amount of controlled combustion in a given area and extrapolate
Estimating abundance of non-motile organisms (3 methods)
-Use of quadrats
-Actual counts
-Measuring population density, percentage cover, and percentage frequency
Community respiration
The total respiration rate for all the populations within that system
Identification tools (list of 6)
-keys
-comparison to herbarium specimens or museum collections
-genetic profiling
-scientific exerptise
-apps for matching bird song, etc
-field guides
Estimating biomass
Find amount of dry mass in a given area and extrapolate
Random sampling
An area is divided into a grid and
coordinates are selected using a
random number generator.
Species
A group of organisms that share common characteristics and that interbreed to produce fertile offspring
Tricellular model
-model of wind currents
-Describes THREE large CONVECTION CURRENTS moving from the EQUATOR towards the POLES in each hemisphere of the earth
-explains the distribution of PRECIPITATION and TEMPERATURE that influence structure and realtive productivity of different terrestrial biomes
Anaerobic
Without oxygen (e.g., water-logged soil)
Gross secondary productivity (GSP) (alt name, definition, equation)
-is assimilation
-TOTAL energy or biomass assimilated by consumers
-food eaten - fecal loss
Nitrogen fixation
The conversion of nitrogen gas (N2) into compounds containing nitrates
Commensalism
A SYMBIOTIC relationship in which one organisms BENEFITS and the other is NEITHER HARMED NOR HELPED
K-strategist (definition + examples)
Species that tend to produce a SMALL number of offspring, whichINCREASES their SURVIVAL RATE and enables them to survive in long-term climax communities.
-e.g., whales, humans
Carrying capacity
The maximum population size that a given area can support sustainably
Limiting factors (definition)
Biotic or abiotic factors which lead to a limit in the population growth
Zonation (definition and contributing factors)
Changes in a community along an environmental gradient.
Arrangement/patterning of plant communities or ecosystems into parallel/sub-parallel bands in response to an ENVIRONMENTAL FACTOR CHANGING over DISTANCe
Due to factors such as:
-changes in altitude
-latitude
-tidal level
-distance from shore (coverage by water)
-climate
Pyramid of biomass (2 points)
-Represents the standing stock or storage of each trophic level
-Measured in units such as grams of biomass per square meter ( m-2), or Joules per square metre (J m-2)
Parasitism
A SYMBIOTIC relationship in which one species is BENEFITED and the other is ADVERSELY affected
Producers (3 points)
-also known as AUTOTROPHS
-typically plants or algae that produce their OWN food using photosynthesis
-form the FIRST TROPHIC LEVEL in a food chain
Density-dependent Limiting Factors (definition + example)
Limiting factors RELATED to how densely packed a population is
-e.g., competition
Stochastic
Having a random probability distribution
Species
richness
Number of species in a community that is useful comparative measure
Realised niche
The actual conditions
and resources in which a species
exists due to biotic interactions
Environmental Gradient (what is is + what it does + example))
-A line that joins locations A and B
-Displays a change in certain abiotic conditions
-E.g., going up a mountain leads to a change in altitude, temperature, air pressure, and UV radiation
Niche (definition)
Describes the particular set of abiotic and biotic conditions and resources to which and organisms or population responds.
edit prompts for drawing carbon cycle and nitrogen cycle
Species diversity
A function of the number of species and their relative abundance
Human activities impacting carbon and nitrogen cycles (list of 4)
-Burning fossil fuels
-deforestation
-urbanisation
-agriculture
matter cycling
Primary producers
In most ecosystems, primary producers convert light energy into chemical energy through photosynthesis
Extrapolation
Estimating or concluding something by assuming that EXISTING trends will CONTINUE
Percentage frequency (equation and example)
the number of occurences divided by the number of possible occurrences
-e.g., if a plant occurs in 5 out of 100 squares in a grid quadrat, then the percentage frequency is 5%
Denitrification (definition + example)
The conversion of nitrogen containing compounds, into Nitrogen gas
-this happens in water-logged soil by anaerobic bacterial
Biomagnification
The INCREASE IN CONCENTRATION of persistent or non-biodegradable pollutants along a food chain
-the buildup of mercury inside apex predator fish as a result of low levels of mercury accumulating in other organisms up the foodchain
Net Secondary Productivity (NSP) (equation)
Calculated by subtracted respiratory losses from Gross Secondary Productivity
NSP = GSP - R
where GSP = food eaten - fecal loss
Sampling strategy
The strategy designed to collect sufficient, appropriate data for a study that provides a valid representation of the system being
studied
Habitat
The environment in which a species noramlly lives
terrestrial
relating to the earth i.e. ecosystems occurring on land
Chemosynthetic organisms (!!!!)
Produce their own food WITHOUT SUNLIGHT using the energy stored in chemical bonds
-SO FUCKING COOL !!! OFTEN DEEP SEA OCEAN CREATURES THAT LIVE ON THERMAL VENTS AND EAT THE CHEMICALS
Density-independent Limiting Factors (definition + examples)
Limiting factors UNRELATED to population density.
-e.g., natural disasters, weather change
Alternative stable state (3 points)
-A stable state that is the result of a series of feedback loops and random events
-These give rise to a particular set of biotic and abiotic factors
-A particular system may be able to exist under several alternative stable states, but will be the result of the random events and feedback
Competition (definition + examples)
The interaction between organisms trying to attain the SAME RESOURCES.
-may be food, mates, territory, nesting sites
Climate
The average of the weather over a relatively longer period of time (about thirty years of data is required to give an area’s climate)
Precipitation (types and definition)
-Rain, snow, sleet, hail
-water that moves from a gaseous state, condenses, and falls to the ground
Terrestrial abiotic factors (list of 8)
-temperature
-light intensity
-wind speed
-particle size
-slope
-soil moisture
-drainage
-mineral content
Ecosystem
A community and the physical environment with which it interacts
Respiration
The conversion of organic matter
into carbon dioxide and water in
all living organisms, releasing
energy
Flows in nitrogen cycle (list of 7)
-Nitrogen fixation by bacteria and lightning
-absorption
-assimilation
-consumption (feeding)
-excretion
-death and decomposition
-denitrification by bacteria
Decomposer
-The micro-organisms which secrete digestive enzymes over dead/decaying organic material, recycling nutrients and convertint it into simpler soluble organic substances
-Organisms that feed on this are known as DETRITIVORES
Mutualism
A SYMBIOTIC relationship in which BOTH partners benefit
Transect
A straight line along which samples can be taken
Maximum sustainable yield
Equivalent to the NET PRIMARY or NET SCONDARY PRODUCTIVITY of a system
Ecological pyramids (type + what they do)
-Pyramids of numbers, biomass, and productivity
-QUANTITATIVE models that are usually measured for a GIVEN AREA and TIME
Productivity:Respiration Ratio
-ratio between how PRODUCTIVE a system is and HOW MUCH RESPIRATION is happening
-as a system approaches its climax community, gross productivity EQUALS respiration rates and so P:N approaches 1
Percentage cover (definition)
An estimate of the area in a given frame size (quadrad) covered by the plant in question
Productivity
The conversion of energy into biomass for a given period of time
Bioaccumulation
The BUILD-UP of persistent or non-biodegradable pollutants within an organism or trophic level because they cannot be broken down
e.g., buildup of human hormones in fish that live in a polluted river
S-shaped Curve
A population growth curve showing exponential growth FOLLOWED by SLOWED growth until a carrying capacity is REACHED
Freshwater abiotic factors (list of 5)
-Turbidity
-flow velocity
-pH
-temperature
-dissolved oxygen
J-shaped curve
A population growth curve showing EXPONENTIAL GROWTH with NO carrying capacity reached
Nutrient and energy pathways (3 points)
-The ways that nutrient/minerals and energy move through an ecosystem
-Tend to become more complex as a system undergoes succession
-often represented by a FOOD WEB
Net Primary Productivity (NPP) (equation)
Gross primary productivity minus respiration losses
GPP - R
2 impacts of human activity on the carbon cycle
-Combustion of fossil fuels releases carbon dioxide, contributing to global warming
-Clearing of carbon sinks (e.g., vegetation) increases carbon dioxide in the atmosphere
Weather (definition and variables)
The conditions in a given place at any time.
-measure by temperature, air pressure, precipitation, wind speed, humidity
Simpson Diversity Index (D) (equation)
N(N-1) / Sum of n(n-1)
-N is total number of all organisms of ALL SPECIES found
-n is the number of INDIVIDUALS of a certain species
Predation
The CONSUMPTION of one species (the prey) by another (the preadtor)
Symbiosis
individuals living on or in individuals of another species where ONE OR BOTH species use the
others resources.
Includes mutualism, commensalism and parasitism.
Biome
A collection of ecosystems sharing similar climatic conditions
Succession
the process of change over time
in an ecosystem involving pioneer, intermediate
and climax communities.
Resource Partitioning
The FUNDAMENTAL NICHES of two
species overlap and through
competition a NARROWER
realized niche is developed
Aquatic
Relating to water; ecosystems dominated by water
Carbon sinks (definition + examples)
Stores in a system containing a lot of carbon.
-e.g., forest, peat bog (THROWS YOU INTO THE BOG TO REDUCE CLIMATE CHANGE)
Aerobic
Uses oxygen
Community
A group of populations living and interacting with each other in a COMMON HABITAT
systematic sampling
samples are taken at regular intervals, e.g.
every 3m
Climax community (3 points)
-There is no one climax community; is a set of alternative stable states for a given ecosystem
-states depend of climatic factors, properties of the local soil, and a range of random events that can occur over time
-historically is considered as the community of organisms at the end point of succession, BUT succession never ends (unless it is the cotitular TV series)
Herbivory
The consumption of a plant species by an animal.
Primary vs secondary succession
-PRIMARY occurs in an environment with NO PREVIOUS LIFE or in a BARREN HABITAT
-SECONDARY occurs in a PREVIOUSLY INHABITED AREA that has experienced a disturbance; there is still soil
Abiotic factors (definition + examples)
The non-living, physical factors that influence the organisms and ecosystem
e.g.: temperature, sunlight, pH, salinity, precipitation
Pyramids of numbers
Graphically displays the numbers of
organisms at each trophic level in
a food chain
edit energy flows
Trophic level
The position that an organism occupies in a food chain, or the position of a group of organisms in a community that occupy the same position in food chains
Lincoln Index (calculation)
(n1 x n2) / nm
n1 is number caught in FIRST SAMPLE
n2 is number caught in SECOND SAMPLE
nm is number caught in SECOND SAMPLE that were MARKED
Site description
A detailed description, giving the location of biotic and abiotic conditions of the ecosystem/community being studied.
Photosynthesis (definition)
The conversion of water and CO2 in chloroplasts, using light energy, into organic matter
Flows in carbon cycle (list of 6)
-consumption (feeding)
-death and decomposition)
-photosythesis
-respiration
-dissolving
-fossilisation
Quantitative data
Measuring the quantity (e.g., number of species) of something
Ecology
The study of interactions among and between organisms in their abiotic environment.
Fundamental niche (definition)
Describes the full range of conditions and resources in which a species could survive and reproduce
Qualitative data
Measured by the QUALITY (e.g., appearance or location) of something rather than quantity
Marine abiotic factors (list of 5)
-Salinity
-pH
-Temperature
-dissolved oxygen
-wave action
Pyramid of productivity
Flow of energy through a trophic level, indicating the rate at which that stock/storage is being generated
Motile
Organism capable of movement
r-stragetists (‘r’ is purposely not capitalised) (definition + examples)
-Species that produce LARGE numbers of offspring so they can COLONISE new habitates quickly and make use of short-lived resources
-e.g., bacteria, algae, rodents, frogs
Estimating abundance of motile organisms (2 methods)
DIRECT methods include actual counts (e.g., by aerial photography) and sampling
INDIRECT methods include Lincoln Index (capture-mark-recapture)
Insolation
The amount of solar radiation reaching a given area.
Biotic factors (definition + examples)
The interactions between the organisms in an ecosystem.
-e.g.,: Predation, herbivory, parasitism, mutualism, disease, competition
