question

succession =

answer

the process by which the species composition of a community changes over time

question

the ultimate association of species achieved is called the...

answer

climax community

question

Serial stage =

answer

each stage of community change during succession

question

pioneer species =

answer

the earliest species to arrive at a site; typically are able to disperse long distances and arrive quickly at disturbed sites

question

climax community =

answer

the final seal stage in the process of succession; generally composed of organisms that dominate in a given biome

question

primary succession =

answer

the establishment and development of plant communities in newly formed habitats previously lacking plants

question

examples of primary succession:

answer

sand dunes, lava flows, rock bared by landslides or receding glaciers

question

secondary succession =

answer

the development of communities in disturbed habitats that contain no plants but still contain organic soil (ex. plowed fields, hurricane uprooted trees

question

succession in intertidal communities can occur rapidly after a disturbance due to...

answer

the short generation time of dominant species

question

J.T. Curtis and R.P. McIntosh ordered the mature forest communities of southwestern Wisconsin along a...

answer

continuum index

question

two factors that determine when a species becomes establishes in a sere:

answer

1. how readily it invades newly formed or disturbed habitat 2. how it responds to changes in the environment

question

the diverse array of processes governing the course of succession are divided into 3 categories of mechanisms:

answer

1. facilitation 2. inhibition 3. tolerance

question

succession mechanism Facilitation category =

answer

embodies clements' view of a developmental sequence in which each species paves the way for the next

question

succession mechanism Inhibition category =

answer

inhibition of one species by the presence of another is a common phenomenon. when inhibition is acting, succession moves forward only through the death and replacement of established individuals

question

succession mechanism Tolerance category =

answer

a species can invade new habitat and become established independently of the presence or absence of other species

question

communities are typically most diverse and complex at _____ stages of succession

answer

intermediate

question

colonizers are ___-selected late successional species are ___-selected

answer

r K

question

successions of microorganisms and scavenging animals on excreta or dead plants and animals have no ____

answer

climax at all

question

example of dissimilatory process ex. of assimilatory process

answer

respiration Nitrogen reduction

question

4 principal classes of carbon-cycling processes:

answer

(1) assimilatory/dissimilatory processes (mainly photosynthesis and respiration) (2) exchange of CO2 between atmosphere and oceans (3) precipitation/dissolution of carbonates (4) methanogenesis (small but important contributor to overall carbon cycle and global climate change)

question

mean residence time for C in atmosphere is about.. mean residence time for C in oceans is about..

answer

5 years 224 years

question

precipitation (as Ca and Mg carbonates) leads to formation of ___ and ____ rock

answer

limestone and dolomite rock

question

humans add carbon to the atmosphere at a rate of..

answer

about 7 billion tons annually

question

nitrogen fixation =

answer

the process of converting atmospheric nitrogen into forms producers can use, including ammonia which is rapidly converted into ammonium(NH4+) and nitrate(NO3-)

question

nitrogen fixation occurs in..

answer

some species of cyanobacteria, free living species of bacteria and in bacteria that form mutualism with plants

question

abiotic nitrogen fixation occurs when...

answer

lightning, wildfires, or combustion of fossil fuels provide energy to convert N2 into NO3-

question

nitrification =

answer

the final process in the nitrogen cycle, which converts ammonium to nitrite, and then from nitrite to nitrate

question

mineralization =

answer

the process of breaking down organic compounds into inorganic compounds

question

denitrification =

answer

the process of converting nitrates into nitrogen gas.

question

human activities have ____ the amount of nitrogen put into terrestrial ecosystems

answer

doubled

question

watershed =

answer

the total upstream drainage area contributing water flow to any point on a stream

question

cutting and burning of tropical forest and subsequent cultivation can only support agriculture for...

answer

2-3 years

question

how many non indigenous species have been introduced to the US?

answer

50,000

question

What percentage of species listed under the US Endangered Species Act are threatened because of competition, predation, parasitism, and herbivory by introduced species?

answer

40%

question

What is a country that has predominantly alien flora and fauna?

answer

New Zealand

question

Large, flightless birds called _____ were exterminated from New Zealand by Maori natives before Europeans arrived.

answer

moas

question

Alien species are most likely to disrupt natural ecosystems when they...

answer

assume ecosystem roles of native species

question

introduction of a single exotic predator is most likely to disrupt ecosystem function if the introduced species is a _____ predator

answer

keystone

question

what percentage of the earth's topsoil is lost to erosion each year?

answer

1%

question

Application of fertilizers to aquatic ecosystems stimulates primary production just as it does in agricultural ecosystems. In aquatic ecosystems, the enhanced production can eventually lead to...

answer

anoxic conditions (no oxygen)

question

Application of fertilizers to aquatic ecosystems stimulates primary production just as it does in agricultural ecosystems. In aquatic ecosystems, the enhanced production can eventually lead to:

answer

bacteria

question

Why has acidic precipitation been particularly devastating to rivers and lakes in certain regions, such as the northeastern United States, Canada, and Scandinavia?

answer

Waters there are oligotrophic and thus lack bases to buffer acid inputs.

question

When fungal populations in soils are reduced as the result of contamination by copper, one consequence is:

answer

reduced decomposition of organic matter

question

The benefits of many pesticides are often short-lived, and their amounts must be increased for continued effectiveness because:

answer

they select for evolution of resistance in target organisms.

question

Oil pollution is a serious problem throughout the world. Petroleum kills organisms by...

answer

disrupting biological membranes and coating surfaces of organisms

question

Peaceful uses of nuclear power may eventually be limited by:

answer

the problem of disposing of nuclear wastes

question

The Vienna Convention for the Protection of the Ozone (1985) and the Montreal Protocol (1987) included agreements for the phasing out of:

answer

Chlorofluorocarbons

question

If you were asked to provide a "ballpark estimate" of global atmospheric CO2 concentrations at the beginning of the industrial revolution (1750-1850), you would choose:

answer

300 ppm

question

The oceans represent an important sink for anthropogenic CO2. In what form is the excess carbon stored?

answer

as calcium carbonate sediments

question

Not all human activities contribute to heating of the atmosphere. Which has a net effect favoring atmospheric cooling?

answer

effects on albedo of the earth's surface

question

Which of the following ecosystem services is considered indirect and dependent more on maintenance of intact ecosystems and less on availability of particular species?

answer

production of clean air and water

question

In the United States, how many kilojoules of fossil fuel energy are consumed for every kilojoule of food energy we consume?

answer

10

question

What percentage of the earth's land area is currently used for crops or permanent pastures?

answer

35%

question

About how many species of plants and animals worldwide have been described and given Latin names?

answer

1.5 million

question

About how many species of plants and animals exist on the planet?

answer

over 10 million

question

conservation of global biodiversity is best served by directing efforts toward areas of:

answer

high diversity and high endemism

question

What fraction of medical prescriptions filled in the United States are drugs extracted directly from flowering plants?

answer

one-quarter

question

Researchers Tilman and Downing have demonstrated which of the following?

answer

more stable biomass production during drought in high-diversity systems

question

What is a good estimate of the background rate of species extinction?

answer

one species per year

question

What is a good estimate of the current rate of species extinction?

answer

one species per day

question

Catastrophic destructions, like the one caused by the impact of a bolide with earth at the end of the Cretaceous, create opportunities for new types of biological associations. In the case of the end-Cretaceous catastrophe:

answer

mammals and birds filled ecological vacancies left by dinosaurs

question

About how often have catastrophic destructions of the magnitude of the end-Cretaceous bolide impact occurred?

answer

at intervals of 10 to 100 million years

question

Which kind of extinction has been linked to collisions of bolides with earth?

answer

mass extinction

question

Which kind of extinction is caused by humans?

answer

anthropogenic extinction

question

Human activities have been identified as the causal factor in numerous documented extinctions. Which specific cause has been identified in the majority of cases examined?

answer

habitat reduction and modification

question

Colonization by humans of Australia, the Americas, Madagascar, and New Zealand was soon followed by which of the following events?

answer

extinction of a substantial portion of the vertebrate fauna

question

In which setting have exotic species posed a larger threat to the native biota? islands or mainlands?

answer

islands

question

Why do aquatic systems seem particularly vulnerable to disruption by exotic consumers?

answer

because of the predominance of top-down control of community structure by consumers

question

Which species has become a pest after its introduction elsewhere from North America?

answer

Comb Jelly

question

Which of the following incorporates demographic information about a particular population into a simulation model to predict the probability that it will avoid extinction within a given period, typically 100-1000 years?

answer

population viability analysis

question

Which principle associated with the theory of island biogeography can be helpful to individuals designing parks and reserves?

answer

the species-area relationship

question

Which species was rescued from the brink of extinction?

answer

california condor

question

A stream flowing through or under a glacier can leave deposits of soil and rock in its path. After the retreat of the glacier, these deposits appear as a long, winding hill in the landscape, creating a unique microhabitat. What is the name applied to this structure?

answer

esker

question

Which animal plays the role of "ecosystem engineer" by consuming most available vegetation during a period of irruption?

answer

spruce budworms

question

Ancient farming practices, wildfires, ecosystem engineers, and modern logging practices all share a common impact on the landscape. What is it?

answer

creation of a landscape mosaic

question

A GPS requires a minimum of ___ signals to accurately determine location.

answer

four

question

Images acquired from airplanes and satellites can be used to identify features on the earth's surface and their locations in landscapes. Which wavelengths of reflected radiation make it easy to identify areas of vegetation, which typically stand out as bright red in the images produced?

answer

visible and near-infrared

question

T/F? Habitat fragmentation results in increased patch isolation, smaller patch size, and higher patch numbers, all of which have uniformly negative effects on species richness.

answer

False

question

Two habitat patches of the same area differ in their shapes. One is circular, the other narrowly elliptical. Which has the greater ratio of edge to interior?

answer

narrowly elliptical patch

question

The World Land Trust and Wildlife Trust of India are collaborating to protect important habitat corridors to ensure the long-term persistence of which charismatic animals?

answer

Asian elephant

question

The research conducted by Taylor Ricketts on movements of Colorado butterflies is of particular interest because it clearly demonstrates that...

answer

the habitat matrix may be composed of a variety of habitats that differ in their effects on movements of individuals from one patch of suitable habitat to another.

question

Earl Werner and colleagues found that turnover (percentage change in species composition per year) of larval amphibians in wetlands in southeastern Michigan was directly related to which property of these wetlands?

answer

connectivity to other wetlands

question

The degree of resolution at which an organism experiences variation in the landscape is referred to as:

answer

grain

question

The landscape scale that an animal experiences in the course of its movements is referred to as:

answer

extent

question

If you were studying an animal, like the wildebeest, which covers huge areas in its annual movements, you would probably opt for a study that examined landscape features at relatively coarse (and/or large):

answer

grain and extent

question

Scientists monitoring acidified precipitation in the northeastern United States and Eastern Europe during the 1960s found that the pH of rainwater dropped to as low as ___

answer

4.0

question

Which substance is an important precursor of acidified precipitation?

answer

sulfur dioxide created from burning fossil fuels

question

Acidified precipitation leaches various elements from forest soils. Heavy leaching of two elements in particular leads to poor growth and even mortality of trees. Which elements are these?

answer

Calcium and Magnesium

question

Which element was monitored to determine the rate of bedrock weathering in the Hubbard Brook Experimental Forest?

answer

Calcium

question

What did researchers estimate to be the rate of bedrock weathering (in terms of bedrock depth) in the Hubbard Brook Experimental Forest?

answer

1 mm/yr

question

Which element is usually absent from soil parent material?

answer

nitrogen

question

Leaves of different plant species decompose at different rates, depending largely on which property?

answer

lignin content of the leaves

question

While mycorrhizae assist plants in obtaining nutrients from soils, they may also provide an additional benefit to plants. What is it?

answer

protection from pathogenic organisms

question

Under what conditions of available soil phosphorous are mycorrhizae most likely to benefit plants through uptake of phosphorous?

answer

low

question

Research by Björn Lindahl and colleagues has shown that mycorrhizal fungi tend to be more active in which portion of the vertical profile of a forest soil?

answer

deep

question

In which of the following ecosystems would you expect to find litter on the forest floor contributing the largest percentage of total organic biomass?

answer

temperate needle-leaved forest

question

oligotrophic =

answer

relatively low in plant nutrients

question

Where in the Neotropics would you expect to find oligotrophic soils?

answer

Amazon Basin

question

Traditional slash-and-burn agriculture in the humid topics alternates 2-3 years of crop production with how many years of forest regeneration?

answer

50-100 year

question

examples of alkaloids?

answer

nicotine, morphine, atropine (Not Tannic Acid)

question

the Lotka-Volterra predator-prey model is ____ while the competition model is ____

answer

exponential model logistic model

question

Larvel ticks do acquire lyme disease bacteria from infected hosts that they feed upon. which animals are most typically involved in this transmission?

answer

small rodents, like chipmunks and mice

question

allelopathy =

answer

the chemical inhibition of one plant (or other organism) by another, due to the release into the environment of substances acting as germination or growth inhibitors.

question

halitosis =

answer

bad breath

question

sympatric speciation =

answer

the process through which new species evolve from a single ancestral species while inhabiting the same geographic region.

question

Allopatric speciation =

answer

or geographic speciation is speciation that occurs when biological populations of the same species become vicariant, or isolated from each other to an extent that prevents or interferes with genetic interchange.

question

the three mutualism types?

answer

Trophic: the transfer of energy and nutrients between two species. Dispersive: interactions in which one species receives food in exchange for moving the pollen or seeds of its partner. Defensive: interactions in which one species receives food or shelter in return for protecting its partner species from predators or parasites.

question

Where would you expect more variation in mean monthly temperatures, from the coldest month to the warmest month? northern or southern hemisphere?

answer

northern

question

The Intertropical Convergence Zone (ITCZ) is a region of substantial uplift of air heated in contact with the earth's surface. At any given time of year, where is the ITCZ located?

answer

at the earth's solar equator (not true equator)

question

Your family is planning a holiday trip in late December and early January to the resort city of Rio de Janeiro, located in Brazil at about 21 degrees south latitude. Because this trip is during the southern hemisphere summer, your family can count on:

answer

at least some rain, possibly heavy, during their vacation

question

rank the 3 forest biomes from least to most diverse

answer

boreal, temperate seasonal, tropical rain forest

question

Ice skaters get excited when ice begins to form on the surfaces of temperate lakes during winter. At this time, where is the coldest water in the lake?

answer

at the top, just below the ice

question

T/F? Much of the effort in the study of life histories has been to understand the fitness consequences of changing the allocation of limited time and resources to competing functions.

answer

True

question

Which british biologist first placed the clutch size of birds in an evolutionary context?

answer

David Lack

question

what is the key evolutionary concept underlying the Red Queen hypothesis?

answer

through sex and genetic recombination, hosts present a moving target for evolving pathogens.

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