Energy and Ecosystems Flashcards
1
Q
describe a system
A
network of interacting components
2
Q
are most environmental systems open or closed
A
open systems
3
Q
positive feed-back loop
A
self-reinforcing ; drives the system toward one of the two extremes
4
Q
negative feedback loop
A
drives the system in the opposite direction ; acts as an inhibitor/self-limiting ; stabilizes the ecosystems
5
Q
what state are natural systems often in
A
dynamic equilibrium
6
Q
what can contribute to homeostasis
A
dynamic equilibrium
7
Q
what are two properties of homeostatic systems
A
resilience and resistance
8
Q
natural systems often have _____ kind of properties
A
emergent
9
Q
what approach do most environmental scientists take to study earth’s natural systems
A
holistic ; considers the interconnectedness of various aspects of the environment and society
10
Q
what do delineations and definitions of systems depend on
A
the question being asked
11
Q
what are the five main subsystems of Earth
A
- biosphere
- geosphere
- hydrosphere
- atmosphere
- anthroposphere
12
Q
geosphere
A
includes the solid Earth
13
Q
atmosphere
A
envelope of gases that surround the planet
14
Q
main components of the hydrosphere
A
oceans ; glaciers ; ice caps ; ground water ; surface water bodies
15
Q
what are the frozen parts of the hydrosphere known as
A
cryosphere
16
Q
biosphere
A
living and recently deceased/decaying organisms
17
Q
anthroposphere
A
human activities and impacts and the built environment
18
Q
what makes up an ecosystem
A
all organisms (biotic) and non-living entities (abiotic)
19
Q
ecosystems are biotic and abiotic entities that ______
A
occur and interact in a particular habitat at the SAME time
20
Q
____ flows through an ecosystem
A
energy
21
Q
___ is recycled in an ecosystem
A
matter
22
Q
how is energy converted to biomass
A
through primary productivity
23
Q
true or false
all ecosystems have the same level of primary productivity
A
FALSE
24
Q
what limits primary production
A
available nutrients
25
adding what can boost productivity in an ecosystem
adding nutrients
26
is it beneficial to have excess nutrients in an ecosystem
NO - excess can alter an ecosystem in ways that can cause severe ecological and economic consequences
27
what do ecosystems provide us with
natural resources and wide variety of services
27
how do earth systems and processes differ
in their characteristic spatial and temporal scales
27
what can give scientists the ability to study highly complex systems or those with unwieldy temporal/spatial scales
studying subsystems and creating models
28
landscape ecologist POV
broad perspective on how landscape structure influences organisms
29
describe landscapes
consists of ecosystem patches spatially arrayed in a mosaic
30
what tech is assisting landscape ecology in conservation and regional planning
remote sensing technology
GIS (graphical information sensing)
31
four main biogeochemical cycles
1. hydrologic cycle
2. carbon cycle
3. nitrogen cycle
4. phosphorus cycle
32
what cycle moves water throughout the global environment
hydrologic cycle
33
human impacts on the water cycle
1. Altering earth's surface and vegetation = increase surface runoff and erosion
2. Damming rivers to create reservoirs = increase evaporation
34
how do carbon flux between organisms and the atmosphere happen in carbon cycle
photosynthesis and respiration
35
where is most of the carbon contained
in sedimentary rock
36
where else (besides main reservoir) holds substantial amounts of carbon
1. oceans
2. soils
37
human impacts on carbon cycle
1. human activity has moved carbon from long-term deposits (like fossil fuels) to the atmosphere
2. Removing forests = remove carbon from vegetation reservoirs and release into the air
38
what are vital nutrients for plant growth
nitrogen and phosphorus
39
what must be done to nitrogen before plants can use it
nitrogen gas in the atmosphere must be "fixed" by specialized bacteria or lightning
40
can plants use nitrogen right from the atmosphere
NO - it has to be fixed first
41
human impact on nitrogen cycle
1.Fixing atmospheric nitrogen with fertilizers = increase flux of nitrogen from the atmosphere to earth's surface
2. Destroying wetlands = reducing nitrogen's return to the air and reducing the amount of nitrogen picked up from nitrogen pollution
42
where is phosphorus the most abundant
sedimentary rock ; with substantial amounts in soil and oceans
43
is there appreciable atmospheric pools of phosphorus
NO
44
human impact on phosphorus cycle
runoff from agricultural land has contributed phosphates to surface water bodies = widespread eutrophication (ecosystems enriched with nutrients, increasing the amount of plant and algae growth) and hypoxia (lack of oxygen, strangulation) of organisms
45
open vs closed system
open ; Systems that receive inputs of both matter and energy and produce outputs of both
closed ; Systems that receive inputs of both matter and energy and produce outputs of energy NOT matter
46
example of negative feedback
predation-prey relationships
47
what type of feedback loop is rare in natue
positive feedback loop
48
example of positive feedback loop
erosion
49
dynamic equilibrium
Processes in a system move in opposing directions at equivalent rates resulting in their effects balancing out
50
homeostasis
Tendency of a system to maintain constant or stable internal conditions
51
resistance vs resilience
resistance ; strength of the system's tendency to REMAIN CONSTANT ; resistance to disturbance
resilience ; measure of how readily the system will return to its ORIGINAL STATE after being disrupted
52
Emergent properties
Characteristics that are not evident in the individual components on their own
53
importance of the geosphere
○ Provides physical and chemical foundation for life on earth
○ Source of mineral nutrients and other materials that cycle through Earth system
54
what are the two MAIN gases in our atmosphere
nitrogen and oxygen
55
has the atmosphere changed since the formation of earth
YES - Chemical composition has changed from the formation of earth till now
56
is an atmosphere unique to earth
NO - other planets also have one
57
what are some examples of water NOT part of the hydrosphere/cryosphere
- Atmospheric water (part of the atmosphere)
- Water in living organisms (part of the biosphere)
- Water found in rocks and minerals (part of the geosphere)
58
process of motion of energy through an ecosystem
Energy arrives as radiation from sun ----> powers the system -------> transformed (processes include photosynthesis and respiration and decay) --------> exits as heat
59
what happens to the nutrients when organisms die
it REMAINS in the system
60
describe the relationship between energy and matter
The flow of energy through a system drives the constant recycling of matter
61
biomass
Organic material of which living organisms are formed ; results from photosynthesis
62
Gross primary production (GPP)
Conversion of solar energy to the energy of chemical bonds in sugars by autotrophs
63
Net primary production (NPP)
Energy that remains after respiration that is used to generate biomass
64
what primary production represents the energy or biomass that is available for consumption by heterotrophs
net primary production
65
Secondary production
Total biomass that heterotrophs generate by consuming autotrophs
66
High net primary production ecosystems
Ecosystems were plants convert solar energy to biomass rapidly (freshwater wetlands, tropical forests...)
67
Low primary production ecosystems
○ Tundra
○ Deserts
* Open oceans
68
Nutrients
Elements and compounds that organisms consume and require for survival
69
Macronutrients vs Micronutrients
macronutrients ; Elements and compounds that organisms need in large amounts
Micronutrients ; Nutrients needed in small amounts
70
describe Limiting factor in an ecosystem
If one of these nutrients (mainly nitrogen or phosphorus) is present in less than ideal amounts, it will place a limitation on plant or algal growth
71
Ecotone
Transitional zones where two ecosystems meet and interact (sharing elements)
72
patches (referring to ecosystems)
ecosystems or areas of habitat for a particular organism
73
Metapopulation
If patches of a species are distant enough = organism's population might become divided into subpopulations each occupying a different patch
74
Remote sensing
Technologies that collect information about a target object from a distance (like satellite images)
75
Geographic information system (GIS)
Computer software that takes multiple types of spatially referenced data and combines them on a common set of geographical coordinates
76
Biogeochemical cycles
Movement of materials and energy through and among these systems
77
Characteristics of systems
○ Planetary-scale subsystems that make up earth system
○ Interaction of biotic and abiotic components
Diversity of temporal and spatial scales among natural systems and processes
78
Reservoir (pool)
Location where materials in a cycle remain for a period of time before moving to another reservoir
79
Residence time
Amount of time a material in a cycle remains in a given pool or reservoir before moving to another reservoir
80
Flux
Movement of materials among reservoirs
81
Sources
Reservoirs that release more nutrients than they accept
82
Sinks
Reservoirs that accept more nutrients than they release (stores)
83
Turnover time
The time it would take for all of the atoms of a particular material to be flushed through a reservoir
84
transpiration (water cycle)
the released of water vapor by plants through leaves
85
how does water return to earth
precipitation
85
how does water return to atmosphere
evaporation or transpiration
86
why is carbon (carbon dioxide) pulled out of the atmosphere
photosynthesis
87
how is CO2 released into the atmosphere
1. Carbohydrates (like glucose) produced in photosynthesis are used by autotrophs to fuel their own respiration and release some back
88
driving force of climate change
Removing CO2 from the atmosphere back to the hydrosphere, geosphere and biosphere has not been able to keep pace with the CO2 entering
89
Nitrogen fixation
N2 must be fixed (combined) with hydrogen in nature to form ammonia and the water-soluble ions (ammonium) can be used by plants
90
two ways to accomplish nitrogen fixation
1. Intense energy of lightning strikes
2. Action of specialized bacteria (ex. Cyanobacteria)
91
Nitrification
Ammonium ions are converted into nitrite ions and then into nitrate ions
92
importance of decomposers in nitrogen cycle
Once the decomposers process the nitrogen compounds, they release ammonium ions = ions are now available to nitrifying bacteria to convert them once again to nitrates and nitrites
93
Dentification
○ Denitrifying bacteria convert nitrates in soil or water back into gaseous nitrogen
○ Completes cycle by releasing nitrogen back into atmosphere as gas
94
major steps of the nitrogen cycle
1. nitrogen fixation
2. nitrification
3. dentification
95
is there extensive amounts of phosphorus available to organisms
NO - most is in rocks
96
how is phosphorus a limiting factor to plant growth
Very little phosphorus is available to organism = limiting factor for plant growth (plants can only take phosphorus up their roots when its dissolved in water)
97
major steps of the phosphorus cycle
1. phosphorus is mobilized by weathering ; released phosphate ions into water
2. Phosphate dissolves in lakes/oceans and precipitates into solid form before settling at the bottom and re-entering the geosphere as sediments
3. Once plants uptake phosphorus by their roots, secondary consumers receive it by consuming the plants and release phosphorus through excretion
4. Decomposers break down phosphorus-rich organisms and waste to return the phosphorus to the soil
98
Ecosystem ecology
study of energy and material flow among biotic AND abiotic components of systems
