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Ecol 419 > Midterm 1 Material > Flashcards

Midterm 1 Material Flashcards

1
Q

What is ecosystem ecology?

A

Is the study of the flow of energy and materials and matter in between, and out of an ecosystem

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2
Q

Do ecosystems have size and boundaries?

A

Yes

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3
Q

What are the state factors?

A

Cl, O, R, P , T
Climate
Organisms
Relief
Parent material
Time

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4
Q

Why are the state factors important?

A

There are what cause ecosystem variation

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5
Q

How does climate impact ecosystems?

A

they determine the global distribution of biomes

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6
Q

How do organisms impact ecosystems?

A

The organisms and potential organisms are what drive ecosystem processes

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7
Q

Can their be abiotic ecosystem processes? What does more processes, biotic or abiotic?

A

Yes, degradation due to UV light from sun, but biotic processes are more common

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8
Q

How does relief impact ecosystems?

A

influences state of ecosystem by influencing local variation in ecosystems, for ex: at top of hill water will flow off and at bottom of hill water will pool. Soil will act similarly.

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9
Q

How does parent material influence ecosystems?

A

It influences the rate of soil formation and type of nutrients in the soil.
For ex: granite versus basalt, the minerals in granite rock tend to be lighter (like quartz), the minerals in basalt are dark so that influences the nutrient availability to plants.

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10
Q

How does time effect ecosystems?

A

It can effect development of soil (more time, more pedogenesis) and successional processes of plants and recovery after disruption to an ecosystem.

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11
Q

Why do we care about causes in ecosystem variation?

A

Because we can predict how the system will react to disturbances and how changes in the state factors will cause this

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12
Q

How does phosphorus availability change over time in an ecosystem?

A

As soil develops, all types of phosphorus becomes less available in the soil

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13
Q

What is a primary source of phosphorus?

A

Its rock minerals that are weathering into soil

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14
Q

What is occluded phosphorus?

A

is phosphorus that binds to soil minerals tightly so that it’s not available to anything

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15
Q

What is non occluded phosphorus?

A

is free or available phopshorus

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16
Q

What is organic phosphorus?

A

Is phosphorus that is put in plant material (litter or trees), is an organic form of phosphorus.

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17
Q

What types of soils are in tropical soils?

A

They have soils like ultisols and oxisols, these are soils that ar ehighly weathered (have experienced more pedogenesis)

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18
Q

What happens to the Nitrogen amount as ecosystems develop?

A

Early ecosystem- no nitrogen (as nitrogen needs to be fixed to be available)
Mid ecosystem- High amounts of nitrogen
Late ecosystems- nitrogen depletes

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19
Q

How does carbon amounts change as ecosystems develop?

A

Early ecosystem- low
mid- high
late- lowers

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20
Q

What limits temperate (old) ecosystems?

A

Nitrogen, as the ecosystem gets olds, the nitrogen declines and the carbon availabilyt depletes

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21
Q

How do available phosphorus amounts change as ecosystems develop?

A

it stars off as nothing, mid way it increases, and then reduces

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22
Q

Why do Nitrogen, phopshorus, and carbon availability over time matter?

A

To know how the system will respond if you add N, C, P for ex: you add nitrogen to soil that’s limited in nitrogen will it overload?
Want to know how it respond to human management

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23
Q

What are pools?

A

is amount of nutrients there

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24
Q

What are fluxes?

A

Is the movement of nutrients

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25
Q

What are ecosystem processes?

A

flows and flux of matter and energy in an ecosystem

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26
Q

What three things are common in ecosystem processes?

A

Inputs
Output/losses
Transformations

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27
Q

What are some inputs? (name 6)

A

Human input
Erosion
Atmospheric deposition
fixation (like nitrogen fixation)
leaching
weathering

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28
Q

What are 6 outputs?

A

Respiration
Leaching
volatilization
absorption
transport away
transform to a resistant form

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29
Q

What are the four types of transformations?

A

Organic to inorganic (glucose to CO2)
Inorganic to organic (Nh4 to amino acid)
Oxidized to reduced (Co2 to methane)
Reduced to oxidized (Nh4+ to NO3-)

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30
Q

What are the two types of research?

A

Empirical- is what you measure, regards data collection and observation, to find patterns
Mechanistic- Having a sense of overall function of the data, is predictions based on empirical research

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31
Q

Why is empirical research important?

A

Because you need data to create models for ecosystems

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32
Q

Can the walker syers model indicate the availabilty ove rother nutrients?

A

Yes, you could determine the sate of the environment and then find the amount of another nutrients at that state of ecosystem development.

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33
Q

In the tropics what is the minerals charge? How does that make them hold onto phosphate?

A

Has a positive charge, makes them hold onto PO4- .

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34
Q

What did the prof do in hawaii to recreate the walker syers model but for nitrogen and carbon?

A

She measures multiple diff areas with the only variability in soil being age to find out why the nutrient availability was leading to varying plant production.

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35
Q

What are the two independent state factors?

A

time and parent material

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36
Q

What is climate?

A

the average weather over 30 years

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37
Q

What five things effect climate?

A

Latitude
Altitude
Vegetation
Humans
Geology

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38
Q

How does latitude effect climate?

A

They form 5 basic climate types like tropical, dry, temperate, continental, and polar, through the formation of wind cells and differing exposure to light

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39
Q

How does altitude effect climate in terms of temperature?

A

As you increase in elevation you decrease in temp, because air is thinner so fewer collisions between them reradiates heat

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40
Q

How is the altitude effect similar to latitude?

A

As you move at differing latitudes you get different ecosystems at differing elevations (polar ice, tundra, taiga, temperate, tropical), altitude works same way further from equator.

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41
Q

How does altitude effect climate through rainshadows?

A

Most warm air blows on shore, the air rises and cools causing a lot of rain , than dry air descends promoting evaporation (rain shadows)

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42
Q

How does Hawaii get effected by rainshadows?

A

Wind comes up the mountains of mauna loa and mauna kea causing tons of ppt before and then a rainshadow after

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43
Q

Why is there many invasive flowers built in resorts on hawaii?

A

Because resorts are built on dry side of hawaii so they plant the flowers on wet side on dry side to attract tourists

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44
Q

How does elevation effect the ecosites you see in hawaii?

A

High elevation results in tundra, tundra ecosites on top of mauna loa and kea

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45
Q

How does vegetation influence climate? (name 4 ways)

A

albedo, rugosity, evapotranspiration, shade

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46
Q

How does vegetation influence climate through albedo?

A

More vegetation equals less albedo as it causes more absorption of heat.
Grassland crops, sand, forests, soil/exposed ground, has reflection values of 10-30%

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47
Q

How does vegetation influence climate through rugosity?

A

Over rougher terrain (more vegation) you get different wind patterns, flat terrain less vegetation you get smoother air flow.

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48
Q

Why in grasslands is grass greener under canopy of trees?

A

Hydraulic lift, birds on canopy cause fertilizer, shade results in less evapotranspiration

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49
Q

How does rainforest vegetation effect climate?

A

low albedo resulting in low surface temp, evapotranspiration results in high latent heat loss, low sensible heat loss, high ppt rates

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50
Q

How does pasture vegetation effect climate?

A

High albedo so high surface temps, high sensible heat loss, low latent heat loss as low evapotranspiration, less ppt

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51
Q

How do humans effect climate systematically?

A

Have drivers (increased co2) which effects the natural system (increased co2 warms atmosphere) which then results in feedbacks (increased temps) with then effects human system (increased co2 for energy to turn fans).

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52
Q

How does airflow get effects by humans?

A

Buildings alter airflow, airflow gets altered by climbing up buildings.

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53
Q

How does albedo get effected by humans?

A

Buildigns, asborn a lot of sunlight, asphalt, clear cutting

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54
Q

How does evapotranspiration and shade get effected by humans?

A

clear cutting

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55
Q

How does geology affect climate?

A

color
Composition (carbonate cycle and roughness)
soil development (amount of carbon in soil)

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56
Q

How does the carbonate cycle effect climate?

A

volcanism can break down carbonate, spew it into the air, warm the air, marine organisms release carbon into air while building calcium carbonate, carbon can be uptaken by rocks through weathering (cools atmosphere)

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57
Q

How does soil development effect climate?

A

effects it large scale as it determines vegetation and determines carbon sequestration.

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58
Q

What is latent heat versus sensible heat?

A

Latent heat triggers a phase change (is heat of evaporation)
Sensible heat is is heat that increases temp

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59
Q

What need mor energy, a phase change or increasing temp?

A

A phase change

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60
Q

What is a boundary layer?

A

is thickness of turbulent versus smooth layer, roughness determines the thickness of the layers we get.

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61
Q

Where is most of earths water stored?

A

In oceans at (96.5%)

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62
Q

How much of earths water is freshwater?

A

2.5%

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63
Q

Where is earth’s freshwater stored?

A

Groundwater (30.1%) and glaciers and ice caps (68.7%), and surface freshwater (1.2%)

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64
Q

Where is earth’s surface freshwater stored?

A

Ground ice and permafrost (69%) and lakes (20.9%)

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65
Q

What are the 10 fluxes in the water cycle?

A

Evaporation, transpiration, sublimation, condensation, transportation, precipitation, deposition, infiltration/percolation, flow, plant uptake

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66
Q

Where is water held in wetlands?

A

in pools in the ground

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67
Q

Where is water held in tropical soils?

A

is held in vegetation

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68
Q

Why is water held above ground in tropical forests?

A

Because soils are low in organic matter, organic matter holds water like a sponge, wetlands have a lot of organic matter in soil so it gets held in soil.

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69
Q

Where is water held in deserts?

A

in groundwater and vegetation (but little amounts)

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70
Q

Why do water fluxes matter?

A

to able to see how much water leaves system and enters it

71
Q

What happens during transpiration?

A

Water comes out of leaves through stomata, water is in vapor form in the mesophyll cells in leaf, heat causes the water to leave the mesophyll cells and exit the leaf through the stomata.

72
Q

Why does the boundary layer (layer above the leaf) matter?

A

It’s still air at surface of leaf that will slow transpiration, it stops plant from drying out too quickly.

73
Q

How do plants alter their boundary layers?

A

Change there leaves surface rugosity in order to determine turbulence of boundary layer and therefore the amount of transpiration that will occur

74
Q

What do the thick cuticles of plants do?

A

they slow the exchange of carbon dioxide for water vapour

75
Q

Whats the danger in transpiration for a plant?

A

only way to get co2 in is to leave water, so in dry conditions if the only way the plant get co2 is losing water, so if there’s a huge water vapor difference, then a lot of water exits plant

76
Q

What’s the difference between C3, C4, and CAM?

A

C3- is in most plants (rice, trees, shrubs) means that the first molecules that carbon gets fixed into in plant is a three carbon molecule.
C4- In corn, means that the first molecule carbon gets fixed into is a 4 carbon molecules
So 4 carbons more, C4 uses carbon mor efficiently and loses less water
In CAM (pineaplles), co2 enters plant at night and becomes an acid, stops plant from losing water by opening stomata during the day

77
Q

Why do we care about C3,C4, and CAM plants?

A

The distribution of the types of photosynthesis shows where the plants are dominant.

78
Q

Where do C4 plants dominate?

A

in more arid, hot&dry areas as they use carbonate more efficiently

79
Q

What’s the benefit of making all plants have a CAM type of photosynthesis?

A

They use less water, is more resources efficient

80
Q

What is evapotranspiration?

A

Is evaporation and transpiration combined

81
Q

What factors effect evapotranspiration (7 factors)

A

atmospheric humidity, temperature, types of plant, soil type, availability of water (is it in pools or ground water), ions in water, wind

82
Q

Why does it matter to know evapotranspiration values in ecosystem?

A

Tells you how much water your losing in your water budget in an ecosystem

83
Q

What is crown drip?

A

is water that falls of edges off canopy of tree

84
Q

What is throughfall?

A

Water that falls straight through plant

85
Q

What is stemflow?F

A

vertical flow of water along the trunk of the plant

86
Q

How do you collect bulk ppt and throughfall?

A

It gets funneled into a container thats placed under the tree

87
Q

How do you collect stem flow?

A

Put collar around tree, collectes flow and then gets funneled into a bucket.

88
Q

Why would you want to collect stemflow, throughfall, and crowndrip?

A

Want to know how much water is there and where its going, and the chemical composition of each type. Sometimes the nutrients (pollen, organic matter) on the laves will fall on foliage below or there can be dust, soot, microplastics, and dead bugs etc.

89
Q

Why do you want to plant plants on the drip line of crown drip?

A

because you want plants to feed off crown drip and also want to water there to irrigate the trees roots

90
Q

What are other ways of knowing?

A

Indigenous ways of knowing which we understand plants with all four aspects of our being (mind, body, emotion, and spirit). Western thinking only considers two (mind and body).

91
Q

What is soil?

A

a matrix of mineral and organic materials with porosity and structure, interacting with atmosphere and water and supports life

92
Q

Soil is composed of what?

A

50% air and water, 50% solid (45% mineral matter +5% organic matter)

93
Q

What is soil physics?

A

is the study of movement of water in soil an fluxes of energy/heat

94
Q

What controls water movement in soil? (4 things)

A

Texture, structure, heat/temp, plants

95
Q

What makes of soils texture?

A

The proportions of sand, silt, and clay in the soil

96
Q

Why do we care about the texture of the soil?

A

They create pore space and structure

97
Q

What is better for plants? Coarse textured of fine texture soil?

A

Coarse textured soil has more water drainage whereas the fine textured soil has more water retained, so fine textured soil

98
Q

What does pore space and texture influence?

A

water movement
Oxygen
Soil bulk density
occurrence of Landslides/soil movement

99
Q

What is a well structured soil? What happens when you don’t have one?

A

A well structured soil has air, water, and nutrients store din pores, when it becomes poorly structured water gets logged, and water and nutrients move slowly down the profile with air being excluded, pores get smaller

100
Q

Why do you want a well structured soil? What are consequences of a poor structured soil?

A

It inhibits plant growth by overwatering, roots need oxygen otherwise can’t respire

101
Q

What’s bulk density?

A

Is the amount of pore space we have and looks at mass per volume, for example: a brick is gonna have a higher bulk density because it has less pore space and therefore more mass per volume. Is particle density plus pore space.

102
Q

How do you determine bulk density?

A

Take core, pound into ground, take intact core sample out, dry it out and then weight it.

103
Q

Why do we want to know about bulk density?

A

Because it allows us to know that the pore size is small and level of compactness as they don’t grow plants well if super compact.

104
Q

Why does tilling increase compaction of soils?

A

Because as it breaks up big chunks of rock, the small bits then fall to bottom and compact forming a very bulk dense layer, this also results in a layer of iron concretion sometimes.

105
Q

What are the layers in a compacted soil?

A

have crust, then tightly packed soil, then blocky soil, then deep compaction

106
Q

What three things do compact soils affect?

A

Water movement
Oxygen
Root growth

107
Q

How does compaction of soil effect oxygen, water movement, and root growth?

A

too few pores results in in too much water, less oxygen, and therefore root growth

108
Q

What are the six soil structures?

A

Granular, blocky, prismatic, columnar, platy, single grained

109
Q

How does soil structure get damaged? Why is this very bad?

A

tilling, this is bas because soil structure takes years and years to build so it’s not quickly renewable

110
Q

What is aggregate hierarchy?

A

That particles (sand/silt/clay) get glued together to become big things, to become even bigger things.

111
Q

Describe the process of microaggregates forming into macroaggregates?

A

Microaggregates are formed by particular organic compounds being glued together with minerals, the glue is a byproduct of bacteria
These microaggregates get glued together by fungi to make macroaggregates

112
Q

Why do we care about aggregate hierarchy? Why do we want to know amount of micro to macro aggregates?

A

-Tells you about the amount of fungi that are there
- Tells you something about how healthy the microbial system is
-Helps you know how well things will grow in soil

113
Q

How do pores and structure effect soil movement (ie erosion, landslides)

A

if soil isn’t glued well it’ll erode.
Landslides will happen when you overload the pore space in a soil with fairly large pores.

114
Q

How does soil temperature change with depth over time?

A

-Deeper soils are warmer and stay consistent over long periods of time
- Shallower soils fluctuate alot over time in temperature

115
Q

Why do shallower soils fluctuate so much in temp?

A

Has heat exchange with atmosphere so seasonal and diurnal changes effect it.

116
Q

Why is soil temperature important?

A

Allows us to see how fluctuations in temperature effects organisms at the surface

117
Q

What is the effect of water on soil temperature?

A

Water buffers changes in soil temperature

118
Q

What is loam?

A

Is the only soil that is not predominantly sand, silt, or clay, contains humus a lot

119
Q

What are the three types of nutrient in soil? What do they do?

A

Primary nutrients, secondary nutrients, micro nutrients, they are elements needed for plants

120
Q

Whats the difference between micro and macro nutrients?

A

Macro- plants need more of it
Micro- plants don’t need as much

121
Q

Where does nitrogen come from for plants?

A

They are fixed from the atmosphere by bacteria

122
Q

Where do nutrients in general come from?

A

From rocks, atmosphere, water, fertilizer

123
Q

If an atmosphere has too much nitrogen and sulfate what happens?

A

it comes down as acid rain

124
Q

How does nutrients in soil come from rock?

A

Through pedogenensis, parent rock is weathered and fragments move upwards, organic material accumulates, and they create soil with nutrients

125
Q

What’s the difference between an alfisol and spodisol?

A

Alfisol and spodisol have differing ph’s , the differences in colors also indicate the different environments they’re from.
The organic layer in alfisols is thick compared to spodisol.
Spodosols have oxidized iron in them.

126
Q

What is white horizon in spodisols?

A

Is the zone of elluviation, organic acid leaches through and accumlates in b horizon

127
Q

What’s the difference between secondary minerals and primary minerals?

A

secondary minerals have changed mineral structures (are recycled)

128
Q

What are characteristics of the oldest soil layer?

A

most highly weathered, most secondary minerals

129
Q

What are the characteristics of the youngest soil layer?

A

weathered, many secondary minerals

130
Q

What are the characteristics of rotten rock?

A

has some primary minerals, is weathering into secondary

131
Q

What are the characteristics of parent rock?

A

composed of primary minerals, hasn’t really gone through pedogenesis

132
Q

What two things do soil/rock minerals do?

for soil*

A

they are a source of micro and macro nutrients (except N)
They control loss and availability of nutrients via CEC

133
Q

How are different rock minerals nutrient sources?

A

Quartz gives silicon and oxygen
Biotite- gives many nutrients such as aluminum
Feldspar- gives potassium, sodium etc

134
Q

If rocks have a lot of biotite what does that indicate of the soil it’ll form?

A

It’ll be really acidic as biotite has aluminum which will make it acidic

135
Q

What is the impact of limestone acting as a parent material?

A

Have a lot more calcium, will make soil more basic as it weathers, will weather very fast

136
Q

Why are clay minerals so important?

A

Because they’re negatively charged so they hold cations

137
Q

What is cation exchange capacity?

A

Is the total quantity of negative surface charges in the soil, it is measured by how many cations it can hold

138
Q

What does CEC determine of a soil?

A

plant nutrient availability and retention

139
Q

What cations do we want attached to our soil? What do we not want?

A

Want base ions (nutrients for soil), don’t want acid cations

140
Q

What is CEC measured in?

A

milliequivalents of negative charge per 100 g of soil

141
Q

How does clay content determine CEC?

A

More clay results in higher CEC, less clay more sand results in lower CEC

142
Q

If a soil is clay heavy, does that mean it has a high CEC?

A

no differing clays have differing CEC’s

143
Q

Why are differing clays have differing CEC’s?

A

Because the clays have differing structures, for example: smectite expands it’s layers resulting in more places to hold cations but mica does not expand as it has potassium holding layers together. Kaolinite and mica have differing CEC’s as kaolinite has only one +Al to one silicon where as the other has two.

144
Q

What does soil pH effect?

A

affects nutrient availability, solubility, and effects plants and biota
Differing nutrients are more available in diff ph’s, macronutrients are abundant at high ph, micronutrients are abundant as low ph.

145
Q

What is the optimal ph for soils?

A

Around neutral

146
Q

What is salinity?

A

The amount of salt in soil

147
Q

Where does salinity come from?

A

Release of salts from weathering of primary minerals
high does of chemical fertilizers
irrigation water

148
Q

What is salinization?

A

When salt is too much and overloads system forming salt crust.

149
Q

How does soil ph effect plant biota?

A

indirectly by ph, acidic soil bad as it take space for nutrients, hydrogen can also get in plants roots and then needs to be pumped out and expends energy

150
Q

Why is salinization a big problem?

A

you can’t just wash the salt away as the soil won’t drain (water just evaporates leaving salt), hard to reverse

151
Q

What is a big consequence of salnization?

A

plants exploding

152
Q

What controls nutrient availability in soil?

A

Weathering, ph, vegetation, soil moisture, temperature, carbon content

153
Q

Where do nutrients in soil come from (chemically)? Given an example of each?

A

They come from above, beside, and below
Above- N nitrogen fixation
Beside- water- ie sulfur
Below- from parent material, for ex aluminum from mica

154
Q

Does organic matter increase CEC?

A

yes

155
Q

In one gram of of soil, how many bacterial cells are there? Species of bacteria?

A

over 1,000,000 bacterial cells, over 16,000 species of bacteria

156
Q

Soil organisms are involved in what aspects of soil functioning?

A

all aspects including (soil fertility, structure/aggregation, organic matter formation, residue decomposition, nutrient cycling/availability, nitrate leaching, and soil fertility).

157
Q

What are soil animals important for?

A

shredding (decomposition) and mixing (aeration)

158
Q

What are soil mesofauna important for?

A

predation and pathogenesis

159
Q

What are soil microbes important for?

A

Nutrient cycling, pathogenesis/disease, chemical breakdown and carbon transformation

160
Q
A
161
Q

Where is most of the world’s carbon?

A

Is accumulated in high altitudes, don’t see much carbon in desert regions

162
Q

What are the global carbon pools from biggest to smallest?

A

continental crusts and upper mantle
ocean
soils and vegetation
permafrost
surface ocean
atmosphere
emissions
land use and change

163
Q

Why do we care about carbon pools, fluxes and cycles?

A

Because we want to see the effects of human changes on it for example fossil fuel burning

164
Q

What are the inputs of the carbon cycle?

A

Primary productivity, secondary productivity

165
Q

What is the definition of humic substances?

A

A subset of the total SOM, no longer recognizable as biologically derived

166
Q

What are the two main types of humic substances?

A

humic acids and fulvic acids

167
Q

What are the two theories of humification?

A

lignin degradation theory
Polyphenol condensation theory

168
Q

What’s special about carbon over silica?

A

makes many diff compounds and makes 4 bonds

169
Q

What are the three traits of humic substances?

A

Large size
High in nitrogen
Variety of functional/reactive groups with an overall negative charge

170
Q

Why do wetlands have such high carbon storage?

A

because it’s very wet and cool so carbon doesn’t degrade

171
Q

How soil carbon formed?

A

litter enters microbial bodies which becomes decomposed

172
Q

What is the lignin degradation theory?

A

Says that lignins have a lot of rings and so rings are cut up on outside by microbes, this creates humus

173
Q

what is the polyphenol condensation theory?

A

that various microbial products all glue together to make humus

Ecol 419 (3 decks)

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