Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Environmental Science 315 > C5 Terrestrial & Aquatic Ecosystems > Flashcards

C5 Terrestrial & Aquatic Ecosystems Flashcards

1
Q

open system

A

a system that can exchange mass + energy (usually heat)
- e.g. tree, ecosystem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

SYSTEMS
- what is a system
- open system
- closed system
- isolated system

A

an assemblage of parts + the relationship between them, which together constitute as a whole

OPEN: a system that can exchange mass + energy (usually heat)
- e.g. tree, ecosystem

CLOSED: a system that can exchange energy but not mass
- e.g. Earth, terrarium

ISOLATED: a system that can exchange neither mass nor energy
- e.g. thermos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

systems approach vs reductionist approach

A

systems: a way of visualising a complex set of interactions by looking at it as a whole

reductionist: divides systems into parts, which are studied separately

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why is a systems approach important?

A

In order to understand our impact on an ecosystem, we must understand how it works as a whole (all interactions and relationships within it).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

levels of organisation

A
  • individual: one organism
  • population: group of organisms from the same species
  • community: a group of populations living together in the same geographical area
  • ecosystem: all the biotic and abiotic factors within an area
  • biome: a large geographical area with distinct flora/fauna, found across different regions
  • biosphere: the zone of Earth where life is supported
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

abiotic vs biotic
- provide examples (3, 5)

A

ABIOTIC: all factors that are non-living.
- climate (temp, rainfall, wind, light intensity)
- chemical (pH of soil/water, salinity, availability of gases)
- other resources (landforms, soil type, water drainage, nesting materials etc)

BIOTIC: all factors that are living.
- animals
- plants
- fungi
- bacteria
- protists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Provide examples of small and large scale ecosystems.

A

Small:
- decaying log
- under a rock
- rock pools

Large:
- tropical rainforest
- savannah/grassland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

condensation

A

water vapour changes state from gas to liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

evaporation

A

water changes state from liquid to gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

evapotranspiration

A

describes the movement of ALL water evaporating from the land into the atmosphere, including:
- transpiration from plants
- evaporation from water bodies
- evaporation from land surface/soil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

transpiration

A

water evaporates from plants (i.e. leaves)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

vapor

A

a gas floating in the air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

runoff

A

when fluid overflows from an area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

precipitation

A

water in ALL states that falls to Earth, including:
- rain
- snow
- sleet
- hail

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

water cycle

A

the movement of water between land, bodies of water, and the atmosphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

groundwater

A

the water present beneath the Earth’s surface, located in rock and soil pore spaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

perlocation

A

the movement of water through the soil and fractured/porous rock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

infiltration

A

the entry of water into a soil or rock surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

sink

A

a reservoir that provides storage for water, such as lakes, ponds, and the ocean

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

primary productivity

A

the process of creating organic compounds by autotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

autotrophs

A

organisms that use photosynthesis to make their own energy
- producers
- drive primary production

Includes:
- plants + algae
- some protists
- some bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

organic compound

A
  • a carbon-based compound
  • at least one carbon is bonded to an atom of another type (usually N, H or O)
  • e.g. carbs, lipids, proteins, nucleic acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

State the chemical equation for photosynthesis.

A

6 CO2 + 6 H2O -> (via sun’s energy + chlorophyll) → C6H12O6 + 6 O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

State organisms that drive productivity in:
- oceanic/marine environments
- freshwater

A

Oceanic/marine: single celled plants, algae/protists, bacteria (PHYTOPLANKTON)

Freshwater: commonly plants + algae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Describe factors that would limit productivity (4)

A
  • not enough reactants (water or carbon dioxide)
  • not enough required nutrients available for autotroph growth (iron, calcium, nitrates, phosphates)
  • too cold
  • not enough light
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

photic vs aphotic

A

Photic: the zone of the ocean that receives sunlight (usually to about 200m down)
Aphotic: the zone that does not receive sunlight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

chemosynthesis

A

using chemical energy to make energy + oxygen
- using chemical E instead of light, to produce the products of photosynthesis
- some bacteria perform this

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

nutrient upwelling

A

when cold, deep, nutrient-rich water is forced up into the photic zone
- results in massive boost of productivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

estuarine environment

A

where a river meets the sea
- salinity changes regularly (tide in = higher salinity, tide out = lower salinity)
- organisms must be very tolerant of changing conditions to survive there

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

viscosity

A

the thickness of a medium
- water more viscous than air
- most aquatic organisms have a streamlined body shape to move easily through the water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

buoyancy

A

the force giving upward thrust
- air: little upthrust, organisms need a skeleton to support their weight
- water: more upthrust, organisms can float and do not necessarily need a skeleton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

turbulence

A

the fluctuations/movement of a body of water
- the more turbulence, the more oxygen is dissolved into the water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

pressure

A

a continuous physical force exerted against something
- air: the higher the altitude, the less dense the air, the lower the pressure
- water: the deeper the water, the higher the pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

3 types of aquatic ecosystem

A
  • freshwater (rivers, lakes, ponds)
  • estuarine (river meets sea
  • marine (reefs, rocky shore, open ocean)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

heterotrophs

A
  • do not make their own food
  • consumers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

decomposers

A
  • a type of consumer
  • CRITICAL to an ecosystem
  • ‘recycles’ organic matter
  • broken down by decomposers, nutrients/components are returned back to the soil, become available again

Includes:
- scavengers
- detritivores: decompose vis oral ingestion of material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

food chain

A

a linear sequence of organisms
- arrows show movement of energy + biomass from producer -> heterotrophs (primary consumer, secondary consumer, etc)
- must label with producer, primary/secondary/tertiary consumer etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

apex predator

A

the top organism of a food chain - no natural predators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

trophic levels

A

the levels at which organisms exist within an ecosystem
- form a pyramid
- producers on bottom
- apex predator on top
- energy loss at each stage

40
Q

Why are trophic pyramids usually limited to 4-5 levels?

A
  • there is a continuous loss of energy within a food chain
  • only 10% of the energy at one trophic level is available to be passed to the next
  • therefore trophic levels are limited as organisms at too high of a level would not have enough energy available to sustain their population
41
Q

food webs

A
  • a diagram displaying a complex set of interactions within organisms in an ecosystem
  • organisms are arranged in rough rows according to trophic level
  • producers at bottom, apex predators at top
  • arrows show movement of energy + biomass from producer -> heterotrophs (primary consumer, secondary consumer, etc)
  • must label with producer, primary/secondary/tertiary consumer etc
42
Q

niche

A

an organism’s role within it’s community, including it’s interactions with other species, habitat, and zone of tolerance

43
Q

fundamental vs realised niche

A

Fundamental: the area an organism could theoretically occupy (set by abiotic factors)

Realised: the area an organisms actually occupies (set by biotic factors - other species)

44
Q

generalists vs specialists

A

Generalists: large niche
- non-specific requirements
- live on a varied diet
- less vulnerable to extinction

Specialists: narrow niche
- specific requirements
- unique habitat/diet
- more vulnerable to extinction

45
Q

Describe the ecological relationship of competition, providing examples. (2 types)

A
  • competition between organisms for food, habitat, or resources

Intraspecific: within a species (Tas devils competing for food, owls competing for nesting)

Interspecific: between different species (dolphins and sharks competing for fish, rabbits and bandicoots competing for habitat)

46
Q

Describe the ecological relationship of predation, providing examples.

A
  • one species hunts and eats the other
  • involves predator-prey cycles (stable negative feedback loop)
  • dolphins and fish, feral cats and bandicoots
47
Q

Describe the symbiotic relationship of parasitism, providing examples.

A

+/-
- one organism benefits at the expense of another
- ectoparasites (on surface), endoparasites (inside host)
- are not in interests to kill host, just gain off it
- tapeworms inside organisms eat food, fleas and lice feed off organism

48
Q

Describe the symbiotic relationship of mutualism, providing examples.

A

+/+
- two organisms live together/interact and both benefit
- clownfish and anenome (fish cleans anenome, anenome provides camoflage), bees and flowering plants (nectar food, spreads plant pollen for reproduction)

49
Q

Describe the symbiotic relationship of commensalism, providing examples.

A

+/0
- one species benefits, the other is unaffected
- whale shark and remora (shark provides food without being affected)

50
Q

sampling

A

using a large range of techniques to estimate population numbers of a species
- needed when total counts are unable to be made

51
Q

What is a transect?
Describe the 2 different types.

A
  • a transect is a line, strip or area used to count/map the distribution of species along the line
  • can be random or follow an environmental feature
  • shows how the diversity of a species changes

LINE TRANSECT: line created with a rope or tape measure, the species along the line are recorded
BELT TRANSECT: a measured strip

52
Q

density

A

the number of organisms per unit area

53
Q

carrying capacity

A

the maximum population size an area can support

54
Q

State the four contributing causes to population size.

A
  • births
  • deaths
  • immigration
  • emigration
55
Q

Describe the factors that determine the carrying capacity of an ecosystem.
(using the acronym: PANDA PAW)

A

Density Dependent:
- Predators
- Availability of resources
- Nutrient availability
- Disease/pathogen spread
- Accumulation of wastes

Density Independent
- Phenomena (natural disasters)
- Abiotic factors
- Weather conditions (general)

56
Q

What type of graphs display how the population of an ecosystem changes over time?

A

population growth curves
- time as IV, pop size as DV
- once curve reaches stability: carrying capacity

57
Q

J curves vs S curves

A

display the relationship between time and how a population size

J CURVES
- exponential growth
- there are no limiting factors on pop size
- unlimited resources
- suitable abiotic factors
- pop size skyrockets, followed by a crash due to overshooting the carrying capacity

S CURVES
- starts with exponential growth
- pop growth slows due to limiting factors (biotic or abiotic)
- pop reaches carrying capacity

58
Q

Why does the population size fluctuate around the carrying capacity line once it has reached it?

A
  • the population has reached the maximum size the area can support
  • small changes in factors lead to small changes in pop size, but overall it will remain relatively stable
59
Q

positive vs negative feedback

A
  • feedback is a circular process
  • output serves as input

POSITIVE
- a CHANGE in the system
- additional, increasing change (like a snowball)
- the system is altered away from the equilibrium
- does not mean a positive effect

NEGATIVE
- STABILITY in the system
- counteracts any change away from the equilibrium
- e.g. predator prey cycle

60
Q

State the key abiotic factors of aquatic environments.

A
  • salinity
  • temp
  • dissolved O2
  • light penetration
  • acidity (pH)
  • exposure
  • tides
61
Q

Describe how being in the tidal zone affects aquatic biotic factors.

A
  • organisms must be adapted to withstand impact of water movement
  • predation opportunities
  • filter feeding opportunities
  • zonation occurs
62
Q

ecological tolerance

A
  • the range of conditions an organism can endure before injury or death

Optimal range: there is the optimum amount of abiotic factor to produce the highest population

Zone of physiological stress: the organism is under stress, due to abiotic factor being too high or low to support normal potential

Zone of intolerance: population is unable to survive, abiotic factors are too extreme

63
Q

State the main vegetation types in Tassie.

A
  • wet sclerophyll
  • dry sclerophyll
  • temp rainforest
  • grasslands/woodlands
  • alpine
64
Q

wet sclerophyll

A
  • infrequent, high intensity fires: wetter, denser forest means less fires, biomass builds up, when fire occurs it burns intensely
  • tall canopy eucalypts (>30m), dense understory layer
  • regenerates via fire (wipes out understory and some canopy trees, new seedlings cover forest floor, competition within these, new dense understory, some grow large to fill gaps of canopy)
65
Q

sclerophyll forest

A

eucalypt dominated forest

66
Q

Outline some adaptations of eucalypt trees that encourage fire in their ecosystems.

A
  • oil in leaves: highly flammable
  • open tree canopy: allow increased oxygen exposure to fuel fire
  • bark: trees drop bark, which piles up and is carried by wind, increasing fire risk and intensity
67
Q

dry sclerophyll

A
  • frequent, low intensity fires: dryer, more sparse forest means more fire, not much biomass, fires burn less intensely
  • eucalypt canopy trees of many different heights/ages due to fire
  • regenerates via fire
68
Q

rainforest

A
  • lots of rain, very dense forest
  • not dominated by eucalypts
  • fern/moss/lichen understory
  • regenerates via natural mortality of older trees: creates gaps in canopy, light is then available to smaller trees, who grow to fill canopy gap
  • not adapted to regenerate after fire
69
Q

grassy woodlands

A
  • low rainfall
  • fertile soil
  • widely spaced trees
  • under threat due to being cleared for farming
70
Q

alpine

A
  • most tree species do not survive over a certain altitude due to: poor soil, extreme climactic conditions
  • vegetation is low lying: grasses/sedges
71
Q

State the abiotic factors that affect vegetation distribution.
- what happens when these factors are overlapped

A
  • rainfall
  • temp
  • soil fertility/geology
  • aspect (slope)
  • light availability
  • fire
  • overlapping of factors results in mixed forest
72
Q

Describe how a low fire frequency will change a sclerophyll forest over time.

A
  • eucalypts do not have the presence of fire to regenerate
  • they do not grow, are overtaken/replaced by temperate rainforest species
  • given enough time, the ecosystem could transition to a complete temperate rainforest
73
Q

State the 1st Law of Thermodynamics and how it relates to ecosystems.

A

“Energy can neither be created nor destroyed, only change form.”
- energy enters via sunlight and is passed/transferred through the trophic lvls

74
Q

Compare the movement of matter with the movement of energy in an ecosystem.

A
  • both move through ecosystems through consumption, passed up through the trophic lvls
  • in both there is loss/waste at each stage
  • matter is a closed system
  • energy is an open system
75
Q

State the factors affecting productivity (Phs) in an ecosystem, and their relationship.

A
  • sunlight availability (proportional, then plateau)
  • CO2 conc (proportional, then plateau)
  • nutrients (proportional, then plateau)
  • temp (proportional, then decrease)
  • H2O (proportional, then decrease)
76
Q

Describe how in an ecosystem how consumers access the energy that producers fix (via Phs).

A
  • consuming plant material (or animals that have consumed plants
  • cellular respiration: releases glucose for energy
77
Q

Outline how energy moves through an ecosystem.

A
  • enters via sunlight
  • is converted to biomass via photosynthesis (producers)
  • passes through food chains
  • is lost through inefficient energy transfer resulting in waste (e.g. heat)
78
Q

ecological pyramids

A

diagrams that represent numerical values of an ecosystem’s trophic levels
- pyramid of numbers (the individual organisms at each lvl)
- pyramid of biomass (dried mass of biomass at each lvl)
- pyramid of energy (the flow of energy at each lvl)

79
Q

pyramid of numbers

A
  • the number of organisms at each lvl
  • NOT ALWAYS a pyramid (no ‘set’ relationship between trophic lvl and number of organisms)
80
Q

pyramid of biomass

A
  • the total dried mass of living organisms at each lvl
  • USUALLY a pyramid
  • measured in grams/sq m (g/m^2)
  • measured at a singular moment in time
81
Q

pyramid of energy

A
  • the flow of energy at lvls, over a year
  • ALWAYS a pyramid
  • measured in joules/m^2/year)
  • sunlight not usually shown
82
Q

Describe how to draw an ecological pyramid.

A
  • producers at bottom, follows food chain up the lvls
  • must be scaled as best as possible
  • each lvl must be centred on the one below it
  • must label each level next to it with species name, number value, and units
83
Q

State the 2nd Law of Thermodynamics and how it relates to ecosystems.

A

“Energy conversions are never 100% efficient, there is always energy lost as waste.”
- less E available at higher lvls
- less organisms at higher lvls (i.e. more producers than consumers)
= food chains are only limited to 4-5 trophic lvls, there would be insufficient E available to sustain a population

84
Q

Why does the total amount of energy decrease the higher the trophic lvl?

A
  • respiration
  • heat loss
  • moving
  • excretion
  • not all material is consumed/digested
  • this is why (roughly) only 10% of energy available at any trophic lvl is available to be passed on to the next.
85
Q

Describe a special case in pyramids of biomass.

A

Marine biomass pyramids
- is an inverted pyramid
- at higher trophic lvls, organisms have more biomass
- producers do not have much mass (phytoplankton, zooplankton)

86
Q

CARBON CYCLE
- how FF are formed
- processes contributing to atmospheric CO2
- processes decreasing atmospheric CO2

A

FF
- dead matter is buried and not decomposed - turns to FF

CONTRIBUTES
- combustion (burning of FF)
- deforestation
- CR (from organisms)
- decomposition of dead matter
- diffusion from water bodies
eruptions:
- shells (calcium carbonate) turn to sediment
- buried, compacted, undergo pressure and heat
- turn to limestone
- tectonic plate movement brings limestone to surface volcanoes = eruptions

DECREASES
- Phs
- diffusion/dissolving into water bodies

87
Q

nitrogen (why is it, and its cycle, important)

A
  • need for survival (to make protein and DNA)
  • very common (78% atomsphere) however most organisms cannot use this
  • N must be fixed before use
  • nitrogen cycle occurs in all ecosystems
88
Q

State the key processes in the nitrogen cycle.

A
  • nitrogen fixation
  • ammonification
  • nitrification
  • assimilation
  • denitrification
89
Q

nitrogen fixation
- what?
- 3 types

A

atmospheric N is put into a biologically available form, by combining with O or H

3 types
- atmospheric fixation
- industrial fixation
BIOLOGICAL FIXATION
- nitrogen fixing bacteria in soil and roots concert N2 + H2 into ammonia (useful)
- ammonia reacts with water to form ammonium (used by plants

ATMOSPHERE - BACTERIA IN SOIL/ROOTS - AMMONIA

90
Q

ammonification

A
  • decomposers break down AAs from dead organic matter
  • form ammonia/ammonium

DEAD MATTER - BACTERIA IN SOIL/ROOTS - AMMONIUM

91
Q

nitrification

A
  • nitrifying bacteria in soil/roots turn ammonium ions to nitrites/nitrates (used by plants)

AMMONIUM - BACTERIA IN SOIL/ROOTS - NITRATES/NITRITES

92
Q

assimilation

A
  • nitrates/nitrites are taken up by plants via roots
  • plants convert them to proteins/nucleic acids
  • plants are consumed by herbivores
  • plants die - ammonification
93
Q

denitrification

A
  • denitrifying bacteria convert nitrates/nitrites back to N gas, released to atmosphere
  • occurs in O poor environments (soil, groundwater, etc)
94
Q

phosphorus (why is it important)

A
  • not found in atmosphere
  • plays a vital role in plant/animal growth
  • production of DNA/RNA
  • formation of cell membranes + ATP
95
Q

phosphorus cycle
- describe all steps (4), that occur

A

WEATHERING
- P in rocks is broken down via rain + natural weathering
- is washed into soil and water bodies

ABSORPTION
- P is absorbed by plants/animals and used for growth
- P in water is drunk by animals, taken up via plant roots, animals eat plants
- occurs in ocean too

DECOMPOSITION
- dead or waste matter is broken down by decomposers
- P is converted from organic to inorganic (mineralisation)

SEDIMENTS
- over time P gets compacted, with pressure and heat, turns into rock

96
Q

Why does the water/air become less acidic (i.e. have a higher pH) when Phs rate is higher?

A
  • CO2 makes water acidic (lower pH)
  • Phs uses CO2 in the reaction, removing it from the water
  • this makes water less acidic (higher pH)

Environmental Science 315 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions