Eco Pre-final
3 factors of biodiversity
- genetic diversity -spp. diversity -community/ecosystem diversity
practical reasons for protecting biodiversity
- higher biodiversity = greater productivity - higher biodiversity= greater resistance to disturbance more stable environment
How does low disturbance affect biodiversity?
- no disturbance= new immigration or emigration -
Idiosyncratic hypothesis
- some species are more imporant than others, so if important species are present than the community function will be better - happens if keystone species are present - species contributing unequally to their community function
complementarity hypothesis
- the more species, the more product the community - diversity and function is a linear relationship
What factors influence NPP in aquatic systems?
-Nutrient availability- affects blooms of cyanobacteria, higher availability= higher NPP -currents - climate
redundancy hypothesis
-the more species, the more productive the community is until it becomes saturated - logarithmic relationship between species diversity and community function
How can species diversity affect disease transmission?
1. If the species lost compete with or prey on the host, the population density of the host or pathogen will increase. 2. Hosts in more species diverse situations are simply more likely to come into contact with individuals of other species than with their own, reducing the probability of transmission 3. More diverse communities allow hosts to built up greater resistant to diseases because those hosts are exposed to similar pathogens in other species within the community.
Three models of succession
1. facilitation model (Clements)- describes situations in which the earliest colonizers modify the environment that ultimately benefit later arriving species 2. tolerance model- assumes the earliest colonizers modify the environment in neutral ways that neither benefit or inhibit later species 3. inhibition model- assumes early successional species modify the environment in ways that hinder later successional species
species accumulation curve
A graph that plots species richness as a function of the total number of individuals that have accumulated with each additional sample. Determines when most or all of the species in a community have been observed.
redundancy hypothesis
A hypothesis that assumes an upper limit on the positive effect of species richness on community function because once species richness reaches some threshold, the functions of species in the community will overlap.
surrogate species
A species selected as a priority for conservation with the assumption that its conservation will serve to protect many other species with overlapping habitat requirements.
T/F: Studies show that global species pools largely determine the numbers of species present in local communities and that local physical conditions and species interactions are less important
F: Studies show that regional species pools largely determine the numbers of species present in local communities but that local physical conditions and species interactions are also important
T/F: The majority of terrestrial NPP occurs along coast lines
False, The majority of terrestrial NPP occurs in the tropics
redundant species
Having the same function in a community as other species in that community within a larger functional group.
Primary succession vs secondary succession
Primary: An ecological succession that begins in an area where no biotic community previously existed Secondary: Succession following a disturbance that destroys a community without destroying the soil
trophic cascade
Rate of consumption in one trophic level results in change of abundance or composition at lower levels
competitive networks
Sets of competitive interactions involving multiple species in which every species negatively interacts with every other species, thus promoting species coexistence.
beta diversity
The change in species number and composition, or turnover of species, as one moves from one community to another.
Net Secondary Productivity (NSP)
The gain by consumers in energy or biomass per unit area per unit time remaining after allowing for respiratory losses (R).
species composition
The identity of the species present in a community.
T/F: Keystone species have greater effects on energy flow and community composition than their abundance or biomass would suggest
True
T/F: in communities that experience alternative states, succession is typically controlled by strongly interacting species and may show an inability to shift back to the original community when the original conditions are restored
True, this is called hysteresis
Even though a community is said to be stable when it remains in or returns to the original structure and function, why is it difficult to know when a community is stable? a. Because the judgment of stability depends on the spatial scale of the community and temporal scale in which it is followed b.Because the judgment of stability is made irrespective of the size of the community c.Because the judgment of stability does not depend on amount of time since the disturbance d.Because the judgment of stability depends on following the community for at least a lifetime of the researcher
a
How do abiotic factors influence the membership of a species within a community? a. Species must be able to tolerate the environmental conditions. b. Species must have beneficial species present. c. Species must exist in the regional species pool. d.Species must not have competitors present.
a
Inverted trophic pyramids using biomass as the proxy for energy are more likely to occur in which of the following? a. Ecosystems with phytoplankton as the primary producers b. Ecosystems with trees as the primary producers c. Ecosystems with grass as the primary producers d. Ecosystems with a mix of grass and trees as the primary producers
a
Species diversity and ecosystem function relationships have been experimentally tested. These experiments have shown a.mostly positive relationships. b.mostly negative relationships. c.equally positive and negative relationships. d.mostly no relationship.
a
The development of the field of conservation biology was primarily prompted by a. ecologists' realization that species were being lost at an accelerating rate. b. molecular techniques that facilitated the identification of microbial species. c. the movement of species across dispersal barriers by humans, leading to increasing diversity. d. a decline in the rate of speciation leading to lower levels of diversity.
a
What are community functions? a.The processes that control community structure and include plant production, water availability, and disease resistance b.The processes that control community structure and include food and fuel, drinking water, and protection from floods c.The processes that control community services and include plant production, water availability, and disease resistance d.The processes that control community composition and include food and fuel, drinking water, and protection from floods
a
What do the majority of taxonomic groups show in terms of the latitudinal gradient in species diversity? a. There is a negative relationship between species diversity and latitude. b. There is a positive relationship between species diversity and latitude. c. There is a unimodal relationship between species diversity and latitude. d. There is no relationship between species diversity and latitude.
a
What has contributed the most to the observed extinction of terrestrial organisms over the past five decades? a. Habitat loss b. Climate change c. Pollution d. Invasive species
a
What was one of the most important discoveries in the New England salt marsh succession experiment? a. The kinds of species interactions observed in succession depended on the intertidal zone of the experiment; thus, they are considered context-dependent. b.In the middle intertidal zone, competitive interactions emerged under high salt stress. c.In the lower intertidal zone, positive interactions emerged under high stress. d.In the lower intertidal zone, competitive interactions emerged under high stress.
a
When compared on a per unit area basis, which of the following biomes has the highest rate of NPP? a.Tropical forests b.Temperate forests c.Temperate grasslands d.Croplands
a
Which best describes the definition of resource partitioning? a. Resource partitioning predicts that species must use resources slightly differently if they are to avoid competitive exclusion. b. Resource partitioning predicts that species must use resources in the same way if they are to avoid competitive exclusion. c. Resource partitioning predicts that species must use resources slightly differently if they are to avoid competitive coexistence. d. Resource partitioning predicts that species must use resources in the same way if they are to coexist.
a
Which nutrient does not often limit NPP in aquatic and marine ecosystems? a.Sodium b.Nitrogen c.Phosphorus d.Iron
a
Which of the following has not been suggested as a reason why a lower proportion of NPP is consumed in terrestrial ecosystems compared with aquatic/marine ecosystems? a. Terrestrial ecosystems produce more NPP than can be consumed by herbivores. b. Terrestrial plants have a greater amount of structural material than phytoplankton. c.Terrestrial plants have more defenses against herbivores than phytoplankton. d.Predation of herbivores is greater in aquatic than in terrestrial ecosystems.
a
Which of the following is an example of the importance of indirect effects to communities? a. Trophic cascade b. Foundation network c.Competitive hierarchy d. All of the above
a
Which of the following is the correct order from the smallest to largest organization? a, population, community, ecosystem, biosphere b, community, population, ecosystem, biosphere c, population, ecosystem, community, biosphere d, population, community, biosphere, ecosystem
a
Which of the following would be considered an indirect influence of climate on NPP? a.Cold temperatures lowering soil nutrient supply b.Dry soils from low precipitation causing the closure of stomates c.Cold temperatures causing chloroplast membranes to solidify and lose function d.High temperatures causing enzymes to denature
a
Which of the following would lower the amount of net ecosystem exchange (total uptake of CO2)? a. Introducing termites in a tropical savanna b. Planting trees in a fertile grassland c. Treating soils with antibiotics to kill the bacteria d. Fertilizing soils with nutrients
a
Which of the following would promote higher numbers of trophic levels in an ecosystem? a. A large area with greater numbers of individuals in a population b. High frequencies of disturbance c. Low rates of primary production d. Low trophic efficiency
a
flagship species
a charismatic species that may be emphasized in conservation efforts because it helps to garner public support for a conservation project
trophic facilitation
a consumer is indirectly facilitated by a positive interaction between its prey and another species
ecosystem engineers
a keystone species that creates or maintains habitat for other species
Which of the following has the strongest negative impacts on biodiversity across all biomes? a. habitat loss b. global warming c. Invasive species d. pollution
a. habitat loss
lottery and neutral models
all species have equal chances of obtaining resources made available by disturbances, and this allows coexistence
What do rank abundance graphs illustrate?
allow one to plot proportional abundance (pi) of one species in relation to another from most to least abundant
Gross primary production (gpp)
amount of carbon taken up by the autotrophs in an ecosystem
Intense but infrequent disturbances result in...
an entire community reassembly
Alternative stable states are communities that form in a. the same area under extremely different environmental conditions. b. the same area under similar environmental conditions. c.alternative areas and under unstable conditions. d. alternative areas and under stable conditions.
b
Consider the hypothetical butterfly communities illustrated in the figure (flip card over). Which community has the highest species diversity and why? a. Community A because species richness is higher than in community B. b.Community A because species evenness is higher than in community B. c.Community A because species evenness is lower than in community B. d.Community B because species evenness is higher than in community A.
b
Surrogate species are often used as targets for conservation because a. they are keystone species, performing important ecosystem functions. b. their protection results in the protection of many other species and associated habitat. c. they are usually the most endangered species, regardless of how appealing they are to the general public. d. they are the species most likely to benefit from conservation efforts
b
The greatest extinction threat to marine mammal species is associated with a. pollution. b. accidental mortality (bycatch in fishing nets). c. habitat loss. d. climate change.
b
The grouping of animals in trophic levels is done according to a. how related they are genetically. b. the type of food they eat. c. the way they obtain their food. d. their thermal physiology (ectotherm vs. endotherm).
b
Theoretically, which of the following biomes should have the highest GPP? a. temperate grassland b. tropical rainforest c. dessert d. tundra
b
What does the theory of island biogeography predict for islands or island-like areas? a. Species richness on an island depends on a balance between speciation rate and extinction rate. b. Species richness on an island depends on a balance between immigration rate and extinction rate. c. Species richness on an island depends on a balance between extinction rates on small and large islands. d. Species richness on an island depends on a balance between immigration rates and speciation rates.
b
What is an important process driving species diversity and composition at the global scale? a. Species interactions b. Local physical conditions c. Speciation d. Beta diversity or species turnover
b
What is meant by the term "extinction vortex"? a. The simultaneous rapid decline of species' populations leads to the extinction of the species. b. Populations gradually decline in size to a point where they can't recover due to genetic and stochastic factors that lower growth rates. c. Species that have mutualistic relationships with another species both decline, leading to the extinction of both species. d. As a result of habitat loss, whole communities of species go extinct
b
What is the best explanation for why disturbance, stress, or predation can promote species diversity? a. Disturbance, stress, or predation allows the dominant competitor to reach its carrying capacity such that competitive exclusion occurs, and competitive coexistence is maintained. b. Disturbance, stress, or predation keeps the dominant competitor from reaching its own carrying capacity such that competitive exclusion cannot occur, and competitive coexistence is maintained. c. Disturbance, stress, or predation keeps the subordinate species from reaching its own carrying capacity such that competitive exclusion cannot occur, and competitive coexistence is maintained. d.Disturbance, stress, or predation keeps the dominant and subordinate species from reaching their carrying capacities such that they both become extinct.
b
What is the main explanation for global biogeographic regions? a. Evolutionary isolation of biota as a result of ocean drift b. Evolutionary isolation of biota as a result of plate tectonics c. Evolutionary isolation of biota as a result of the formation of Pangaea d. Vicariance of biota as a result of changes in climate
b
What was discovered in the primary succession study in Glacier Bay, Alaska? a.Species richness was highest in the oldest successional stage. b.Soil nitrogen and moisture was highest in the oldest successional stage. c.Spruce germination was lowest in the oldest successional stage. d.All of the above
b
Which of the following threats to diversity is predicted to increase the most in the next 40 years? a. Habitat loss b. Climate change c. Pollution d. Invasive species
b
Why do ecologists use subsets of species to define and study communities? a. Because they typically use plant species to delineate communities b. Because it is essentially impossible to count all the species in communities c.Because ecologists typically do not study microorganisms d.Because it is difficult to study species within different taxonomic groups
b
Net ecosystem exchange (NEE)
balance between carbon gained from photosynthesis and carbon lost from both autotrophs and heterotrophs
A community contains three species of birds. Then, a fourth species is introduced. The fourth species eventually becomes extinct. Which factor(s) could be important in the membership of the fourth species? Biotic interactions Environmental conditions Biotic interactions and environmental conditions Biotic interactions, environmental conditions, and dispersal ability
c
As the leaf area index in an ecosystem increases, what happens to total ecosystem respiration and photosynthesis? a. Photosynthesis and respiration increase at the same rate indefinitely. b. Photosynthesis increases, but respiration begins to decline. c. Photosynthesis initially increases and levels off, but respiration continues to increase. d. Photosynthesis and respiration increase initially, but then both level off.
c
Ballast water carried by ships is released near ports. Why has this activity increased the potential for non-native aquatic species invasions? a. It has given the non-native aquatic species a competitive advantage. b.It has given the non-native aquatic species a physiological advantage. c.It has increased the non-native aquatic species regional species pool. d.It has increased the native aquatic species pool.
c
Based on the information in this chapter, which example experimentally shows that hysteresis is not present? a. Kelp forest communities in which sea otters have been reintroduced b.Black Sea pelagic communities in which non-native jellyfish have been removed c.Fouling communities in which fish have been excluded d.Seagrass communities in which Caulerpa has been removed
c
Currently, the extinction of species is primarily related to a. natural processes such as competitive exclusion and predation. b. increases in volcanic activity leading to the cooling of Earth's climate. c. human activities leading to habitat loss, pollution, and the overharvesting of species. d. increasing ultraviolet radiation due to natural changes in the radiation emitted by the sun.
c
How do ecologists define and delineate communities? a. They count all the species in a given area over a particular amount of time. b. They count only some of the species in a given area but over an unlimited amount of time. c. They use characteristics of the physical environment or biological environment or sometimes both. d. They use characteristics of the physical environment or biological environment but not both.
c
How do you know whether a species interaction is strong and positive? a. Removing the target species results in a sharp decline in the number of interactor individuals b. Removing the interactor species results in a sharp increase in the number of target individuals c. Removing the interactor species results in a sharp decline in the number of target individuals d. Removing the interactor species results in no change in the number of target individuals
c
How does the inclusion of positive interactions modify the intermediate disturbance hypothesis? a. At low levels of disturbance, positive interactions increase species diversity by benefiting the competitive dominant species. b. At intermediate levels of disturbance, positive interactions increase species diversity by benefiting the competitive dominant species. c. At high levels of disturbance, positive interactions increase species diversity by benefiting species experiencing that disturbance. d. At high levels of disturbance, positive interactions increase species diversity by differentially benefitting the competitively subordinate species.
c
The development of population viability analysis has facilitated conservation efforts by providing a. identification of endangered species based on rarity. b. determination of the genetic variation needed for viable populations. c. projection of population growth based on demographic properties of a population. d. the population size at which the extinction vortex occurs.
c
There are multiple hypotheses used to explain the relationship between species diversity and community function. Which hypothesis relies on species partitioning their resources? a. The idiosyncratic hypothesis b. The redundancy hypothesis c. The complementarity hypothesis d.The intermediate disturbance hypothesis
c
Top-down control of NPP in a terrestrial ecosystem is associated with a. the supply of nutrients. b. light penetrating the vegetative canopy. c. consumption rates and prey selection by the top carnivores. d. the amount of precipitation.
c
Two plant species are given different ratios of limited nutrients, nitrogen and phosphorus. The two species outcompete one another under certain ratios but coexist under other ratios. This example fits what model and why? a. Resource distribution hypothesis because both species were able to coexist by having different distributions b. Resource ratio hypothesis because both species needed the same set of unlimited nutrients and thus were able to coexist by using those nutrients in similar ratios c. Resource ratio hypothesis because both species needed the same set of limited nutrients but were able to coexist by using those nutrients in different ratios d. Resource ratio hypothesis because both species needed the same set of limited nutrients but were able to coexist by using those nutrients in similar ratios
c
What does the species diversification time hypothesis propose? a. Tropical regions, because they are more climatically stable, have greater species diversification than temperate and polar regions. b. Tropical regions, because they are less climatically stable, have higher productivity but longer evolutionary time than temperate and polar regions. c. Tropical regions, because they are more climatically stable, have longer evolutionary histories and thus greater accumulation of species than temperate and polar regions. d. Tropical regions, because they are more climatically stable, have higher productivity and thus support greater numbers of species than temperate and polar regions.
c
What is the difference between a foundation species and a keystone species? a. A foundation species has a large effect on a community despite its low abundance whereas a keystone species has a large effect on a community because of its low abundance. b. A foundation species has a large effect on a community by virtue of its high abundance whereas a keystone species has a small effect on a community because of its low abundance. c. A foundation species has a large effect on a community by virtue of its high abundance whereas a keystone species has a large effect on a community despite its low abundance. d. A foundation species has a small effect on a community because of its low abundance whereas a keystone species has a large effect on a community despite its low abundance.
c
Which best describes how the alpine meadows on Mount St. Helens were affected by the period of eruption that occurred in 1980? a. The period created intense and frequent disturbances to the meadows. b.The period created mild but frequent disturbances to the meadows. c.The period created one intense disturbance to the meadows. d.The period created multiple intense and frequent disturbances to the meadows.
c
Which best describes patterns of biogeography? a. Patterns of species diversity and composition at gamma diversity scales b. Patterns of species diversity and composition at beta diversity scales c. Patterns of species diversity and composition at global, regional, and local scales d.Patterns of species diversity and composition at global and regional scales
c
Which contributes more to global NPP, the terrestrial surface or oceans? a. The terrestrial surface, because it has higher rates of primary production than the ocean b. The ocean, because it covers a larger surface area of the globe c. They contribute around the same amount to NPP, because the higher area of the ocean is offset by a lower rate of NPP. d.The ocean, because hot spots of very high NPP in nearshore and shallow ocean ecosystems offset the low primary production of the open ocean
c
Which description of a species accumulation curve would most likely represent an extremely rich tropical bacteria community? a. It would rise curvilinearly and then level off after 50% of the individuals in the samples had been identified. b.It would rise slowly and then level off after about 75% of the individuals in the samples had been identified. c.It would rise in linearly and possibly never level off. d.It would rise in linearly and then level off after 50% of the individuals in the samples had been identified.
c
Which example best describes a community undergoing secondary succession? a. The Pumice Plain on Mount St. Helens b. The broken rocks left by the retreat of a glacier c. The scorch zone on Mount St. Helens d.A recent lava flow on Mount Kilauea, Hawaii
c
Which of the following is an abiotic agent of change that causes a disturbance? a. Trampling that kills shrubs b. A snowstorm that reduces the reproduction of a population of birds c. A hurricane that kills trees d. All of the above
c
Which of the following is not a benefit for conservation biology from the development of molecular genetic techniques? a. Determination of the genetic variation in a population b. Identification of maladaptive genes in populations c. Estimation of the population growth rate d. Identification of the species from which a trade item (e.g., meat, ivory) was derived
c
Which of the following is used as a strategy for simplifying the study of complex food webs? a. Emphasizing only the higher trophic levels b. Placing emphasis on primary producers and herbivores c. Emphasizing species that have strong interaction strengths with other species d. Ignoring the indirect effects of species on other species
c
Which of the following make up the first trophic level in all ecosystems? a. Primary production b. Detritus c. Both primary production and detritus .d. Secondary production
c
Which of the following species would you predict would be most susceptible to extinction? a. A species with a wide distribution but rare in the areas where it occurs b. A species with a narrow distribution (endemic) but with a high population density where it occurs c. An endemic species with a low population density where it occurs d. A species with a wide distribution and a high population density where it occurs
c
Which of the following taxonomic groups has the highest percentage of described (named) species that are threatened with extinction? a. Mammals b. Birds c. Gymnosperms d. Amphibians
c
Which of the following would not be a justification for conserving biodiversity? a. Genetic diversity enhances the capacity of a population to adapt to unique environmental conditions. b. Species richness can provide ecosystem services such as enhanced pollination of crops. c. The spread of invasive species can enhance species richness. d. Humans receive aesthetic enjoyment from biodiversity.
c
Which of the following would provide the best estimate of the diet of a heterotroph? a. Observing the food that it consumes b. Collecting and analyzing its fecal material c. Measuring the isotopic composition of carbon and nitrogen in its tissues and potential food sources d. Capturing the organism and extracting the material in its digestive system
c
Considering how energy transfers between trophic levels, which of the following will be a practical way to help feed the increasing human population with limited resources? a. reduce amount of consumption b. increase meat consumption c. decrease meat consumption d. people would decrease the proportion of plants in their diets
c.
What influences NPP in terrestrial habitat?
climate and its affect on plant growth -temperature-NPP increases at a higher temperature -rainfall- increases up to about 2,400mm/year but will decrease NPP at higher levels -Nutrient- the more nutrients available for plants, the better the plant growth, the higher the NPP -species composition- certain species grow better than others
Pollution disproportionally impacts...
coastal areas
How does species diversity affect community function?
community stability - more diverse communities respond and adapt to stress better (ex. plants can maintain biomass during drought in diverse communities) - greater species richness the greater the community's reaction to stress
A plot of local species richness versus regional species richness for coral reefs showed that 75% of the variation in local species richness was explained by regional species richness. What does this suggest about coral reef communities? a. Local species interactions are important to coral reef species richness. b. Regional species interactions are important to coral reef species richness. c. Local water temperature is important to coral reef species richness. d. Dispersal from the regional species pool is important to coral reef species richness.
d
After wolf reintroduction into Yellowstone National Park in 1995, it was observed that the growth of willows and aspens increased. Based on your understanding of trophic cascades, which is the most likely explanation for this observation? a. Wolves consumed plants that compete with the aspen and willows. b. Wolves disturbed the soil near the willows and aspens, increasing nutrient supply. c. Wolves killed elk and other prey, and the decomposition of the prey carcasses provided nutrients for the plants. d. Wolves killed elk and other herbivores, resulting in less herbivory and greater growth and reproduction by the plants.
d
Allochthonous sources are usually the highest proportion of energy inputs in a. surface waters of the open ocean. b. shallow waters in lakes. c. large rivers near estuaries. d. mountain streams.
d
An ecologist is studying the succession of forest communities by visiting sites that experienced glacial retreat at different times over a 200-year period. What is this method assuming? a. The community acts like a "superorganism." b. Animals play no role in succession. c. A time for space substitution d. A space for time substitution
d
Conservation biology focuses on preserving a. genetic diversity. b. species richness. c. landscape diversity. d. All of the above
d
Ecologists often rely on the measurement of NPP to estimate a.the health of ecosystems. b.the amount of CO2 being taken up by the biosphere. c.how much energy is available for heterotrophs, such as herbivores. d.All of the above
d
Following a disturbance, net primary production in a forest ecosystem would be expected to change during succession in which of the following ways? a. NPP would increase indefinitely, as GPP would increase with greater leaf area. b.NPP would increase, as shading would decrease the amount of plant respiration. c.NPP would initially increase and then level off, as both leaf area and respiration would decrease in later stages of succession. d.NPP would initially increase, then decrease, as the mass of respiring tissues would increase and leaf area would decrease.
d
Given the theory of island biogeography, which island would have the highest species richness? a. An island that is small and far from the mainland b. An island that is small and near the mainland c. An island that is large and far from the mainland d. An island that is large and near the mainland
d
How can the succession experiments presented in this chapter be summarized? a. The studies showed that the facilitation model is most supported. b.The studies showed that the inhibition model is most supported. c.The studies showed that competition tends to be more important early in succession and facilitation tends to be more important later in succession. d. The studies showed that facilitation tends to be more important early in succession and competition tends to be more important later in succession.
d
How does biodiversity differ from species composition? a. Biodiversity is the same as species diversity while species composition is a measure of species evenness. b.Biodiversity is the same as genetic diversity while species composition is the identity of the species present. c. Biodiversity describes the diversity from genes to communities while species composition is a measure of species richness. d.Biodiversity describes the diversity from genes to communities while species composition is the identity of species present.
d
How does the quality of food influence net secondary production? a.By determining the amount of ingested food that is egested b. By influencing the nutrient intake and subsequent growth c. By determining the digestibility of the food d.All of the above
d
Invasive species can lead to the loss of native species diversity through a. competitive exclusion. b. predation. c. changing the environment to make it unsuitable. d. All of the above
d
Resource partitioning theory envisions that resources vary along a resource spectrum. Suppose two communities have the same resource spectrum but Community A has three more species that use the resources. Given resource partitioning theory, what explains the difference? a. The species in Community B show greater specialization and less overlap in their resource use. b.The species in Community B show greater generalization and less overlap in resource use. c. The species in Community A show more specialization and more overlap in their resource use. d.The species in Community A show greater specialization and less overlap in resource use.
d
The influence of plants on the responsiveness of ecosystem NPP to changes in climate and resources involves a. the photosynthetic rate of the leaves. b. the allocation of carbon to the growth of roots versus shoots. c. the inherent capacity of the plant to increase growth. d.All of the above
d
When should removing endangered species from the wild and captive rearing be considered as a conservation tool? a. Never, as it rarely works b. As soon as it is determined that a species population is declining c. Before any decrease in population size is detected d.When demographic models suggest the species has a high probability of going extinct in the wild
d
Which food source would provide the greatest assimilation efficiency for its associated consumer? a. Dead organic matter (detritus) b. Grass c. Fruits d. Mammalian prey
d
Which of the following best describes the current rate of species extinction? a. The same as the long-term extinction rate based on the fossil record b. Double the long-term extinction rate c. Lower than the long-term extinction rate d. 100 to 1,000 times higher than the long-term extinction rate
d
Which of the following describes species-area relationships? a. Species richness decreases with the area sampled and decreases with distance from a source of species. b. Species richness increases with the area sampled and increases with distance from a source of species. c. Species richness decreases with the area sampled and increases with distance from a source of species. d. Species richness increases with the area sampled and decreases with distance from a source of species.
d
Which of the following does the tolerance model propose? a. The early colonizers modify the environment in positive ways for later species. b. The early colonizers modify the environment in negative ways for later species. c. The early colonizers do not modify the environment for themselves or other species. d. The early colonizers modify the environment but not in ways that benefit or inhibit later species.
d
Which of the following is a biotic agent of change that causes a stress? a. A woodpecker boring into a tree to eat insects, reducing the growth of the tree b. A disease that reduces the reproduction of a tree c. A parasite that eventually kills a group of frogs d.All of the above
d
Which of the following is not a biological factor that contributes to the differences in NPP among biomes? a. The leaf area index b. The allocation of carbon to different tissues c. The photosynthesis rate d. The length of the growing season
d
Which of the following is not a factor limiting the utility of using food webs as a tool for understanding ecological interactions? a. Actual trophic interactions can change over time; some organisms change feeding patterns over their lifetime. b. Some organisms are components of multiple food webs . c.Most food webs don't include parasitisms or nonconsumptive interactions such as facilitation or mutualisms (e.g., pollination). d. The role of microorganisms is often over-emphasized.
d
Which of the following would provide the best assessment of a species' endangerment status? a. How abundant (rare) its populations are b. The growth rate of its populations c. Its geographic distribution d. Both the abundance and population growth rate
d
Which organism would have the highest production efficiency? a. Shrew (small carnivorous mammal) b. Coyote (omnivore) c. Grasshopper (herbivorous insect) d. Dragonfly (carnivorous insect)
d
Which subset of species best describes a guild? a.A group of species that all have the same taxonomic affinity, such as birds b.A group of species that interact in a trophic web c.A group of species that function in similar ways but may or may not use similar resources d. A group of species that use similar resources but may be taxonomically distant
d
Why did the example of a reef fish community on the Great Barrier Reef of Australia best fit the lottery model of species diversity? a. Because coexistence of the fishes could be explained by resource partitioning b. Because the fishes had very different diets and territory needs c. Because the fishes occupied vacant sites in a competitive manner d. Because the fishes occupied vacant sites in a random manner
d
Why is food web stability important in an ecological context? a. Stable food webs correspond with stable rates of ecosystem processes such as primary production. b. Stable food webs help to minimize local extinction of species populations. c. Stable food webs can help maintain high species diversity. d. All of the above
d
genetic analysis is used to...
determine the variation of the alleles within a population, allows for educated action to be taken
Ecosystem
everything in a community plus abiotic factors
allochthonous inputs
external energy inputs
Species diversity can be influenced by: a. area of the habitat b. location of the habitat c. disturbance occurring at the habitat d. biotic interactions in the community e. all of the above f. all of the above plus random factors
f
Weak but frequent disturbances result in....
gradual community change
guild
group of species that use the same resources
keystone species
have a large effect on their environment, not because of their abundance but because of the role they play in their comunities
why is more NPP is consumed in aquatic ecosystems than in terrestrial ecosystems?
high turnover of primary producer biomass, resulting in inverted biomass pyramids
Allochthonous sources of energy dominate in (lower/higher) portions of river systems, with autochthonous energy sources becoming increasingly important at the (top/bottom) of river systems
higher, bottom
Earths biota is becoming increasingly....
homogenized
demographic analysis is used to...
identify what life stage is impacted the most by the researched factor
autochthonous
inputs of organic matter that are produced by algae and aquatic plants inside an ecosystem
(High, Intermediate, or Low) disturbance leads to the most biodiversity.
intermediate
alpha diversity
local diversity, equivalent to community diversity and is determined by dispersal, physical conditions, and species interactions
Overexploitation disproportionally impacts....
marine environments
species diversity
measurement that combines species richness and evenness
What nutrients commonly limit NPP in aquatic ecosystems?
phosphorous and nitrogen
pioneer stage of succession
primary succession- usually lichens, mosses and ferns that can grow on bare rock, start building soil
succession
process of change in species composition overtime as a result of biotic and abiotic agents of change
primary production
rate chemical energy is converted by autotrophs, includes chemosynthesis or photosynthesis
GPP is determined by
rate of photosynthesis and leaf area index
gamma diversity
regional diversity, encompasses geographic areas in which the climate is roughly uniform and the species contained therein are bounded by dispersal limitation to that region
species evenness
relative abundances of each species
How to measure interaction strength
remove the interactor species and look at its effect on the target species
Fire is an example of (primary, secondary, tertiary) disturbance.
secondary
lottery models
species diversity in communities is maintained by a "lottery" in which resources made available by the effects of disturbance, stress, or predation, are captured at random by recruits from a large pool of potential species
species diversity combines.... and ....
species richness and species evenness
functional group
species that function in similar ways, but do not necessarily use the same resources
foundation species
species that plays a major role in shaping communities due to their abundance
taxonomic affinity
studying only one taxon
Net primary production definition equation
the amount of energy per unit of time that producers capture by photosynthesis and chemosynthesis, minus the amount they use in cellular respiration NPP=GPP- respiration
sampling effort
the amount of time (e.g. number of days) and other resources spent to sample a specified population of individuals
Net Primary Productivity (NPP)
the energy captured minus the energy respired by producers
intermediate disturbance hypothesis
the hypothesis that ecosystems experiencing intermediate levels of disturbance are more diverse than those with high or low disturbance levels, this is because competitive exclusion is reduced since no one reaches their carrying capacity
species richness
the number of species in a community
conservation biology
the scientific study of the amount of biodiversity (including genetic diversity species richness, landscape diversity) and how human activities are impacting it, and how to best maintain and prevent its loss
Gross Primary Productivity (GPP)
the total amount of carbon fixed by the autotrophs in an ecosystem
primary disturbance
wipes out all life, high intensity, low frequency
