FMAN 212 Final
A forested ecosystem providing recreational opportunities is considered a _____ service.
cultural
Which is not an adaptation of trees to wind disturbance! a. Withstand disturbance due to dense wood (of slow growing species) b. Regenerate from seed c. Sprout d. Thick bark
d. Thick bark
Which is not an example of facilitation? a. soil formation by mosses/lichens b. island effect c. N-fixing plants d. residual plants e. plants exude allelopathic substances into the soil
e. plants exude allelopathic substances into the soil
Earth's atmosphere bears the signature of the presence of living organisms. It has much lower carbon dioxide and higher oxygen concentrations than the atmospheres of Venus and Mars.
true
t of f: A legacy effect in plant succession is defined as the effect of a previous community (before disturbance) on the community that forms after disturbance.
true
t of f: Deforestation is an ongoing threat to forest ecosystems.
true
t of f: Smaller disturbance events are more common than larger ones for continental wind disturbances (tornadoes, downbursts).
true
t of f: The opposite of facilitation during succession is inhibition.
true
t or f: In the tropical zone, once can find forest types that resemble high-latitude boreal forests.
true
t or f: The competitive exclusion principle states that no two species can occupy the same niche.
true
T or F: High albedo means that a large proportion of incoming sunlight is absorbed by a surface.
False
T or F: In the Amazon rainforest water cycle, the main way of eventually returning precipitation to the atmosphere is via rainwater entering streams that flow into the ocean from where water evaporates.
False
How do fire frequency and severity typically relate to each other in forested ecosystems? Explain why!
If a forest has frequent fires, they will almost always be low severity. If the forest has very infrequent fires, they will be very severe fires usually. This is for a few reasons. If a forested ecosystem has frequent fires, chances are the system is used to fires and species are adapted to this- and need it sometimes to spread seeds. However, infrequent fires in a system mean that the system is not used to fires, their species aren't adapted for it really. The growth is older, more packed, and will allow the fire to burn more severely, there is a lot to burn. Trees don't have adaptations like thick bark or tall crowns to avoid a fire ladder up the crown. Frequent fires are of low severity [] because there is not enough time for a lot of fuel to build up between successive fires [] (that would lend itself to high impact on the dominant forest species) Infrequent fires are typically of high severity [] because of large amounts of fuel present []
In high latitudes (i.e. boreal regions), the south aspect has better tree growth. But in dry, temperate regions (e.g. the southwestern U.S.) the north aspect has better tree growth. Explain the causes for each scenario!
In temperate regions, the north sides are cooler thus allowing the trees to maintain more water as the heat doesn't cause stomates to open and evapotranspiration to occur. In high latitudes, it's colder and that warmth on the south aspect helps the trees not get too cold and die since it is already very cold in those areas In boreal forests, the south aspect is warmer [], leading to better tree growth (due to faster decomposition providing adequate soil nutrients []). In the dry southwest, the north aspect has more soil water [] (due to receiving less direct sunlight []), allowing trees to grow there instead of just grasses.
Which statement about land form (topography) is not correct?
Increasing slope angle (steepness) increases solar radiation on northerly aspects
EXTRA CREDIT: Explain why the food web is pyramid shaped (in other words, explain the previous question).
Not all the food eaten by consumers translates into consumer body mass as a lot of the energy of the food eaten is expended for movement, reproduction, maintenance []
Refer to image 31: on dox Plant communities are strongly influenced by topography and soils. Therefore, they can be used as indicators of their physical environment. Based on the table below-showing vegetation communities of northern Idaho, which community is an indicator for high water yield but low timber yield?
Pinus albicaulis/ Abies lasiocarpa
If you are within the middle of a temperate, broad-leaved forest region (like Appalachia), could you still find areas dominated by conifers? If so, where?
Yes, at higher elevations.
Based on your lecture notes you know that the tropics are warmer than the poles because ___.
a lot of solar radiation is absorbed by a small surface area because sunlight strikes the surface at a (nearly) right angle
What is an ecotone? (Please consult section 5.1 of your textbook.)
a transition zone between two vegetation types
The process (flux) by which plants remove CO2 from the atmosphere is [a]. The process by which plants return CO2 to the atmosphere is [b].
a- photosynthesis. b- respiration/ fire
The proportion of incoming sunlight that is reflected by a surface is termed ___. (Watch your spelling!)
albedo
Which has been proposed as a possible explanation for tropical forests having a higher biodiversity than forests of lower latitudes? higher temperature in tropics is aligned with animals' needs for a certain temperature range higher plant growth (productivity) of tropics leads to more individuals that have a higher chance of representing different species all the above
all
The spatial distribution of plants on Earth can be predicted with ____ models.
biogeography
The process by which N2 from the atmospheric is turned into plant-usable ammonium or nitrate by soil bacteria is called __.
biological nitrogen fixation
The subdiscipline of ecology studying factors that influence the diversity of species is ____ ecology.
community
In the hierarchy of life, populations of different species make up a ___, which along with its abiotic environment, constitutes a(n) ___.
community - ecosystem
Afforestation of the rain forest potentially has a number of consequences and climate feedbacks. Select 2 the correct answers!
lowers albedo --> positive feedback increases CO2 uptake from atmosphere --> negative feedback
The conversion of N2 in the atmosphere to plant-usable forms of N (e.g. nitrate and ammonium) is called ______ ______.
nitrogen fixation
Globally, most carbon is stored in the ___.
oceans
In current climate models, climate feedbacks caused by rising temperatures (due to rising levels of CO2 in the atmosphere) are not considered. Explain two examples of climate feedbacks. Include whether what you are describing is a positive or negative feedback.
positive climate feedback- Less trees in tropics means less carbon being held in living organisms- more carbon to cycle through leads to more disaster, eventually increasing temperature. Another issue plant's aren't there to use carbon to grow, thus disrupting the food chain and causing more death. negative climate feedback- less trees means increased albedos- this means a higher reflectance and lowered absorption- lowering temperatures Possible answers are, that with higher temperatures 1) Decomposition increases --> releases CO2 --> more warming (positive feedback) 2) Permafrost melts --> releases methane (a greenhouse gas) --> more warming (positive feedback)]3) Tree mortality increases [due to drought, insects, diseases] ] --> fire risk increases --> more CO2 release [meaning more warming] (positive feedback) [] 4) With higher CO2 levels in the atmosphere and higher precipitation [] --> increases plant growth [] --> lowers CO2 in atmosphere [meaning less warming] (negative feedback) []
Forests are found around the globe in hot, temperate, and cool regions as long as there is sufficient ___.
precipitation water moisture
Regrowth of vegetation after a timber harvest represents ___ succession.
secondary
Define "ecosystem services"!
services that benefit humans and are provided from a functioning ecosystem- like helping purify water & regulate temperature. Benefits that humans freely gain from the natural environment and properly functioning managed ecosystems.
In primary succession, the first organisms colonizing the area do not require ___. (See section 6.1 page 62 of textbook.)
soil
Temperate forests (on average) absorb 88% of incoming radiation. But in the winter (without snow), temperate forests, with their mostly leafless branches, reflect most of the solar radiation that hits forest surfaces. Evaluate each of the two statements!
t and f
Label "temperate forest", "tropical rainforest", and two additional biomes of your choice in the image. refer to image question 19 at top of word dox.
temperate - 6 tropical- 1 tundra-10 desert-4 1 tropical rainforest, 2 tropical deciduous/seasonal forest, 3 tropical grassland/ savanna, 4 desert, 5 temperate rainforest, 6 temperate forest, 7 woodland/ scrubland, 8 boreal forest, 9 grassland, 10 tundra
Under assumptions of a) more precipitation when temperatures increase with climate change and b) plants adapting to warmer temperatures, it is predicted that today's southern edge of the boreal forests will become ____.
temperate forest
Within the temperate zone, ___ determines that the forest is made up of broad-leaved trees in the eastern U.S. and of coniferous trees in the western U.S.
the distribution of precipitation throughout the year
Trajectory stability of an ecosystem means that ___.
there is a predictable pattern of succession and disturbance with the endpoint (climax) of one successional sequence (i.e. species composition, productivity) being very similar to previous endpoints of succession
Forests with their large leaf area are a critical component in the water cycle. This is because trees return water taken up from the soil to the atmosphere through their stomates in a process called ___.
transpiration
Plant leaves play an important role in the water cycle by transmitting soil water to the atmosphere from the interior of their leaves. This process is called ____.
transpiration
In which type of forest would you find the highest species richness, fastest nutrient cycling, and highest forest productivity?
tropical
In dry areas, trees are found on __ slopes of mountains, whereas grasses dominate the opposite aspect.
N
A disturbance that a community is adapted to in regard to disturbance type, intensity, and frequency is called ___.
Natural disturbance
Define ecological niche!
Niche: = habitat (the place niche) + role and position a species has in its environment; how it meets its needs for food and shelter, how it survives, and how it reproduces. OR: A species' niche includes all of its interactions with the biotic and abiotic factors of its environment. OR: An organism's way of life in an ecosystem, including habitat, food, predators, and competition OR: Niche is the place or WHERE the species lives and HOW it operates within the system
Any species that arrives first at a site after disturbance may shape the subsequent succession. This is referred to as ___effect .
Priority effect
Describe the characteristics of a steady state (climax) community.
Broad-leaves species dominating, gaps in the canopy from old trees dying- thus leading to diverse gaps where shade intolerant species can grow. Although the species may shift in location, in general the same amount of the species exists. Although changing, it is steady. In this stage, there is a dominance of trees that reproduce successfully under their own canopy and in gaps [] This community contains various successional stages [0.5p] that are present in fixed proportions []. (The steady state community is seen at a larger, landscape scale.) Alternative answer: The community composition relatively stable: []
Disequilibrium
C. describes the state of ecosystems as constantly changing
Temperature and precipitation do not just shape biomes on the scale of continents. They also affect local communities. How does temperature and precipitation change as one climbs up a mountain?
Temperature decreases Precipitation increases
Sort the steps of the water cycle, beginning with the rain event.
1. Precipitation moves water from the atmosphere to the Earth's surface. 2. On land, water either is taken up by plant roots, enters streams, or ground water. 3. Water moves from roots through stems into leaves, from where it is lost as a gas (water vapor) to the atmosphere through stomates. Water also enters the atmosphere when it evaporates from soils and oceans. 4. Water vapor accumulates in the atmosphere, forms clouds, and eventually condenses (i.e. becomes liquid). Eventually water droplets become too large to remain suspended in air.
Sort the vegetation types of the tropics by their dry-season lengths, starting with the longest dry season.
1. Savanna 2. Deciduous (monsoon) tropical forest 3. Tropical semi-evergreen forest 4. Seasonal rainforest forest 5. Evergreen tropical forest
Give two different examples of invasive species (one with direct, one with indirect effects) and how they have affected the forest community they invaded.
1. emerald ash borer- it is killing ash trees by boring into them. directly altering the ecosystem by killing off a species in it 2. kudzu- it grows over everything in the south and ends up indirectly killing species due to blocking out light sources as it grows. It's not attacking anything, but it's growth then affects other species. Direct []:chestnut blight -> killed chestnut trees ungulates on islands -> eat/decimate native plants Indirect []:kudzu -> smothers native veg. or competition for lightgarlic mustard -> inhibit mycorrhizal fungiintroduced grasses -> in the West à change in fire regimeother examples are possible
At a given trophic level, consumer biomass is about ___% (with wide variation) of the biomass found at the next lower level. 10 30 50 70 90
10
In forests managed for timber production via clearcutting, patterns of succession may be altered from succession after a major disturbance in unmanaged forests. Give two possible differences.
1: a legacy species may not be left behind by foresters, thus not leaving behind something to help start up and alter the new forest 2: foresters often cut in homogeneous patches, not similar to nature. -The successional sequence is cut short (i.e. no old-growth)-Early successional stages are cut out, especially in planation forestry-Forestry may leave fewer legacy trees than a natural disturbance would-Across the landscape, forestry practices create areas of disturbance that are homogeneous in size versus few large and many small disturbed areas due to natural disturbance
List four ways in which dead wood (logs and snags) in the forest contribute to biodiversity (i.e. allow more types of organisms to be present than otherwise).
1: they create little dams and then create small aquatic habitats 2: hold water so that during a drought species have access to water 3: attract mosses and lichens and fungi 4: provide cover/shelter for animals 5: attract invertebrates like wood lice and such. Any combination of 4 []: -food for microbes and invertebrates -growth substrate (mosses), nesting sites for birds, dens for mammals -water reservoirs in seasonally dry forests (decaying logs store moisture) -log jams dam streams creating aquatic habitat (also slowing the flow and reducing erosion)
After disturbance, there are several sources of propagules (i.e. seeds or sprouts) that can shape the early successional community. After a stand-replacing fire that consumes all aboveground plant parts and significantly heats the soil, which type of propagule will be colonizing this site?
A neighboring species wind or animal dispersed seeds could end up on the site.nIf the soil was heated too much then the underground plant parts would die too. If the soil isn't heated to the point of killing serotinous cones and there happen to be some present, they could grow too. But if the heat is too severe, definitely seeds from an area that was not affected by fire. Seeds from the surrounding area will be colonizing the site. (Because seeds stored on site would have been consumed or killed by flames or high temperatures (whether in the soil or as serotinous cones in the canopy). Buds from which sprouts could originate would also have been killed by soil heating in this scenario)
A) List 1 example each of a past and present deforestation and B) describe its consequences for the ecosystem (and society).
A past example is the Fertile Crescent- The oak trees were chopped down and then overgrazing prevented forest regrowth . the land was unsuitable for farming and had to be abandoned. Singapore is a more recent example where the intense deforestation led to a sharp decrease in biodiversity- over 3/4 of it. Even more recently is the continued deforestation of the Amazon/ Tropical rainforests in general. These forests take in a lot of carbon, helping regulate our atmospheric content, while also holding so many species of plants and animals. Our loss of these forests could also result in the loss of medicinal plants for disease, keystone species, and even undiscovered species. The forests also alter the water cycle. Past: Mesopotamia, Europe (Greece); Present: Tropical rainforest (in Asia, or South America) Consequence: Soil loss (and societal impoverishment)
A) In the generalized food web below, name the types of organisms represented by each rectangle. B) What is the term applied to rectangles 1-3? C) What does the direction of the arrows signify? Refer to image 2.27
A) 1: green plants (or primary producers); 2: herbivores (or primary consumers); 3: predators (or secondary consumers); 4: decomposers [] B) trophic levels [] C) the flow of energy [] extra credit given (max) if mutualists and parasites are included on level 2 and 3 AND/ OR if details on decomposers is given: Decomposer insects = detritivores; decomposer fungi = saprophytes
Match the type of fire regime encountered to different regions within the US. 1.Mid-elevation ponderosa pine forests 2.Longleaf pine forests (and broad-leaved oak hickory forests) of lowland eastern or SE regions of U.S. 3.Boreal forests 4.Mesic conifer forests of the (northern) Pacific Northwest; mesic northern and upland broadleaf forests of eastern deciduous forest All Answer Choices A. Frequent Surface fires B. Large crown fires every 50-200 years C. Very infrequent crown fires
A. Frequent Surface fires A. Frequent Surface fires B. Large crown fires every 50-200 years C. Very infrequent crown fires
Primary succession
A. sequence of change in the community that is initiated in an environment without former biological influence
In all forests there is a predictable sequence in secondary succession.. refer to 2.15 image. A) List the type of plants that dominates in each stage of succession B) indicate whether plants in each stage are shade tolerant or not).C) Give the name for the final community (stage 3) (coined by Clements) (Hint: The term is NOT "old-growth".)
A: 1: Herbaceous plants, maybe some scrub/ bushes. 2: pioneer woody trees- conifers, still some understory species early on but then not so much. 3: broad leaved, older growth species like oaks and maples. Also towards the end also some understory growth once steady-state is reached. B: 1: no 2: no 3: yes, species that can grow up in their own shade are now dominant C: steady-state successional stage 1. Herbs (short-lived plants) [], shade-intolerant [0.5p] 2.Shrubs and pioneer (tree) species [], shade-intolerant [] 3. Shade-tolerant tree species [] C) The name for the final community (stage 3) (coined by Clements) is climax (community).
Leaf area is important to the Earth's heat balance.A) How would expanding boreal forest areas and shrinking polar ice sheets, respectively, affect albedo? B) How would both processes affect global average temperatures if you only considered the effect on albedo?
A: Shrinking ice sheets removes some high albedo areas that reflect rather than absorb- this would increase global temperatures because they would have lower albedo now.. Boreal forests are composed of conifers, with have lower albedos due to darker colors of trees- this could also result in warming because they would absorb more heat/ light B: Because they would both result in more low albedo areas, they would result in higher temperatures due to increased absorption. A) Forest expansion: decreases albedo , melting ice caps will also decrease albedo B) A decreasing albedo will increase global temperatures (because more solar radiation is now absorbed instead of being reflected back into space)
The forested biome experiencing very low temperatures is called ___(a) forest. The dominating type of tree there is/are ___(b) because of their ability to withstand low winter temperatures to -40˚C.
A: boreal B: dominated by conifers
In forests, a spatial pattern (i.e. structure) is present in vertical and horizontal direction. List the four vertical layers in tropical forests! refer to image in doc- 2.25
A: emergent layer, B: canopy, C: understory, D: forest floor
EXTRA CREDIT: List a) one adaptation of tree species to survive surface fires b) and one adaptation for recolonization after crown fires.
A: the thick bark ponderosa pine has to reduce susceptibility to frequent fires B: serotinous cones that open from the heat of a fire. a. thick bark [] b. sprouting (hardwoods), OR seeds (small, wind-dispersed), OR serotinous cones [one of the listed adaptations get the points: ]
With rising global temperature it is predicted that boreal forests will expand into current [a] (enter the biome). Under the assumption that higher global temperatures also lead to higher amounts of precipitation, savannas are expected to expand into current [b] (enter the biome).
A: tundra B:grassland
Define invasive species!
An invasive species is a species that is not local to an area, and when it enters that ecosystem, it harms and outcompetes native species, changes the makeup of the ecosystem to work for said invasive species, and can cause environmental harm, economical harm, or harm to humans. The species comes to an area without its natural predators and competition, giving it a preemptive leg up. (Type of) organisms not native to an ecosystem [] and whose introduction does [, or is likely to,] cause economic or environmental harm or harm to human health []
Average global temperatures are increasing due to more greenhouse gases in the atmosphere. This warming will likely cause feedbacks that may accelerate warming (positive feedback) or slow warming (negative feedback). Match the processes to its consequences and associated type of feedback! Note, for all statements that start with "1)" select your answer from the answer options starting with "1)"; for all statements starting with "2)", select your answer from the answer options starting with "2)". Question 1) increased plant (tree) growth 1) increase of drought events 1) thawing of permafrost soil 1) increased rate of decomposition 2) increased rate of decomposition 2) increase of drought events 2) thawing of permafrost soil 2) increased plant (tree) growth either negative feedback, positive feedback, carbon dioxide release, tree mortality and fire leading to CO2 release, methane release, ) increased uptake of carbon dioxide from atmosphere
B. 1) negative feedback A. 1) positive feedback A. 1) positive feedback A. 1) positive feedback D. 2) carbon dioxide release C. 2) tree mortality and fire leading to CO2 release F. 2) methane release E. 2) increased uptake of carbon dioxide from atmosphere
Determine if the following aspects of the carbon cycle represent a pool or a flux. Photosynthesis Vegetation and Soil Atmosphere Plant fossils (fossil carbon) Respiration Ocean Fires Deforestation & burning of fossil fuels
B. Flux A. Pool A. Pool A. Pool B. Flux A. Pool B. Flux B. Flux
Match the subdisciplines of ecology with what they study! the study of how a) the living and non-living environment and b) interactions among species influence how individuals in a population contribute to the gene pool of the next generation the study of how the environment influences the function of an organism studies the dynamics (in time), structure (e.g. age), distribution (in space) of populations study of the interactions among individuals and populations of different species studies the structure (pieces and parts) and function (how the pieces and parts work together) of a system as a whole
B. evolutionary ecology E. physiological ecology C. population ecology A. community ecology D. ecosystem ecology
Secondary succession
B. sequence of change in the community that is initiated by disturbance that does not remove all former biological influence
Match biome or temperature zone features to its respective broad biome! biome is frost free or mean annual temperature is >18 C (65 F) long growing seasons with 4-6 frost-free months hardwoods are a minor component of the forest because temperatures can fall below -40 C (-40 F) in winter winters are dry and the short summers are moderately moist and warm the average temperature of the three warmest months does not differ more than 5C from the average temperature of the three coldest months broadleaved-trees dominate if precipitation is either evenly distributed throughout the year or peaks in the summer; conifers dominate if precipitation is concentrated in winter months
B. tropical forest A. temperate forest C. boreal forest C. boreal forest B. tropical forest A. temperate forest
Forest Ecology is concerned with the interrelationships of forest organisms and their biotic and abiotic environment. Explain what biotic and abiotic means and give an example for each.
Biotic factors are living factors in an ecosystem- plants, animals, fungi Abiotic factors are non-living- rain, temperature, wildfire biotic = living environment; other organisms of the same or different species biotic = non-living environment sunlight, oxygen water, soil, temperature
At which latitudes (given in degrees) can forest be found? Check all that apply! Note that incorrect answers will be deducted from correct ones.
Correct Answers: 0 to 23.5 35 to 55 55 to around 70
Disturbance
D. an event or chain of events that initiates change in community structure, typically shifting the ecosystem to an earlier successional change
Match the level in the hierarchy of life with its definition or description! population community ecosystem biome biosphere E. group of interacting individuals of the same species within a given area A. several interacting species in a given area B. consists of a community and its abiotic surroundings C. communities and their abiotic surroundings at a continental scale D. all living organisms on Earth and their non-living environment
E. group of interacting individuals of the same species within a given area A. several interacting species in a given area B. consists of a community and its abiotic surroundings C. communities and their abiotic surroundings at a continental scale D. all living organisms on Earth and their non-living environment
Succession
E. sequence of change in which a previous set of organisms is replaced by another set better adapted to the current environment
Based on your reading of Chapter 1, which is not a distinguishing characteristic of ecosystems?
Ecosystems are stable, i.e. unchanging in time
Match the canopy features to the successional stage. Young Intermediate Mature Old-growth A. Canopy very dense and low to the ground B. Light is reaching the ground in gaps created by single-tree mortality and accumulated disturbances; leaf area is fairly evenly distributed across the forest height profile C. Canopy is elongated; canopy density does not allow for (much) understory growth D. Canopy is elongated; canopy density is lowered by competition having caused some mortality; vigorous understory layer present
Question Correct Match Young A. Canopy very dense and low to the ground Intermediate C. Canopy is elongated; canopy density does not allow for (much) understory growth Mature D. Canopy is elongated; canopy density is lowered by competition having caused some mortality; vigorous understory layer present Old-growth B. Light is reaching the ground in gaps created by single-tree mortality and accumulated disturbances; leaf area is fairly evenly distributed across the forest height profile
Give one example each of a regulating and cultural ecosystem service!
Regulating- the regulation of temperatures & cycling water Cultural- Spiritual enrichment, "tree worshippers", aesthetics. Regulating: climate regulation, natural hazard regulation (landslides, floods), water purification, waste management, pollination, pest control Cultural: non-material benefits such as spiritual enrichment, intellectual development, recreation, aesthetic values
Define succession OR disturbance!
Succession: sequence of change [] in which a previous set of organisms is replaced by another set better adapted to current conditions [] Disturbance: Event or chain of events that initiates change in community structure ; it usually shifts an ecosystem to an earlier successional stage []
Climate models in combination with biogeography models predict where suitable climate conditions may exist for forest species in the future due to climate change. Assuming that the predictions are accurate, do these predicted future best locations mean that forest tree species will eventually end up there through migration? Discuss in complete sentences!
These models do predict that some tree species will migrate, but they also suggest that some might shrink/ cease to exist- like boreal or montane type forests- because there will not be areas cool enough. Temperate forests would probably move into boreal territory. Southern species might also move north. I know we discussed certain trees that can't exist dominate out west like oaks being able to survive or maybe dominate some areas because of warming temperatures. At the end of the day, some species won't be able to hang on if it gets too warm. Some forest types are their species will be able to persevere. There's also always a chance that some species wont move and adapt fast enough, even if somewhere on earth does have the proper climate. It depends. Some species might not have a fast enough migration rate to keep up with the speed that their optimal climate is shifting away from them. Even if plants could keep up, there are barriers that hinder migration: Ag fields, cities, roads.
Define facilitation and describe an example of facilitation during succession!
facilitation is when a species alters the community for the good of new species growth, on the path of succession, but while doing so, makes the climate less suitable for themselves. An example is how the mosses and lichens create soil essentially over time which allows the early growth like herbaceous plants to come in- and that new growth shades them out and outcompetes them, thus ending their time in the area. Early-successional species modify the environment to become more suited for later successional species and less suited for themselves. [] An example (not just listed [] but described (]) in primary succession: mosses and lichens aid in soil formation (by decomposing rock); soil is needed by all other types of plants in primary succession: early successional species are N-fixers that make the soil more fertile allowing other types of plants to colonize in secondary succession, remnant plants (trees) are perches for seed dispersing animals; therefore these remnant plants facilitate the arrival of other species in secondary succession, groups of established plants act as nurse plants by creating a physical environment less hostile (temp., wind, drought) than out in the open; or perhaps by harboring mycorrhizae needed by other species [island effect]
T or F: With doubled CO2 concentrations in the atmosphere by 2100, thermal zones in mountains are predicted to shift downward by 650-900m.
false
t of f Forests are globally important in providing ecosystem services because they cover most of Earth's land area.
false
t of f: In the temperate zone, all forests are broad-leaved deciduous.
false
t of f: The time of year, when a disturbance happens, does not affect the composition of the early successional community.
false
t of: Cloud forests are found above the clouds on tall mountains.
false
t or f: Ecosystem trajectory stability means that disturbances and succession are absent.
false
t or f: Hurricanes damage all trees along their path (i.e. leave a homogeneous area of destruction).
false
t or f: Primary succession takes place in an area with previously formed soil (and the organism therein) but without plants present.
false
Of all vegetation types on the planet, ___ plants contain the largest amount of carbon.
forest
Define "fuel" and list two fuel characteristics that increase the spread of fire.
fuel= living and dead plant matter/ biomass mostly If you have dry biomass on the ground of the forest, or short younger trees like ponderosa pines that were suppressed- then you have ladder fuels that allow the fire to climb into the crown. Fuel: living and dead (plant) biomass 2 fuel characteristics that increase the spread of fire [ ) · High amount · Continuous distribution on the ground or in the canopy · Vertical distribution as ladder fuel · Low moisture content, high flammability due to chemical makeup
Extra Credit: Under the assumptions stated in the previous question, tropical forests may also expand. However, different models predict the conversion of (intact) tropical forest of the Amazon into ___ (biome, vegetation type) because___ (explain).
grasslands. Deforestation decreases rainfall and increases temperatures. The amazon will start to see less rainfall which waters the trees and other species in the forests less leading to less tree life. With warm temperatures and some rainfall, we'd still see some life and some trees but not a lot of trees. savanna; ...of soil drying due to higher temperatures
Temperate forests and tropical forests during the dry season may enhance transpiration by a phenomenon called ___ in which deep plant roots move water up and out into shallow dry soil via shallow roots. During the day, shallow roots take up this water which is then transpired by the leaves. Without this redistribution of water, shallow roots might dry out, depriving the plant of water and nutrients otherwise supplied by shallow roots.
hydraulic lift
At night, and when the top soil layer is dry, some plant species can take up water with their deep roots and release this water via shallow roots into shallow soil. This is called ___. Later, at daytime, shallow roots take up this water and transport it to the leaves, from which more water enters the atmosphere than would otherwise be possible.
hydraulic lift hydraulic redistribution
Due to human activity, the amount of CO2 in the atmosphere [1] and the amount of plant-available nitrogen [2] have ___ and ___, respectively. Evaluate both statement 1 and 2.
increased - increased
The suppression of fire in ponderosa pine forests has led to the buildup of _________ fuels that result in higher intensity of subsequent fires.
ladder
As plants will shift their distribution to keep up with their optimal (but moving) habitat due to climate change, they will encounter migration barriers.
lakes rivers and streams