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BioGeo Test 3
BioGeo Test 3
49
Geography
Undergraduate 1
12/11/2009

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Term
Succession
Definition
predictable and orderly changes in the composition or structure of an ecological community.
Term
Primary Succession
Definition
Succession that result from the formation of new soil (usually lava flow or retreat of glacier)
Term
Secondary Succession
Definition
Succession started by an even such as a fire or hurricane that reduced an established population to a smaller population of species
Term
ecological management
Definition
the management of human activities so that ecosystems, their structure, function, composition and physical chemical and biological processes that shaped them continue to function.
Term
Explain how ecological and natural area management can be thought of as the manipulation of successional
processes, disturbances, or both.
Definition
Human influence on an area disrupts the natural process of succession (prevention of forest fires)
Term
Allogenic Succession
Definition
describes a succession where the stimulus for change is an external one.

i.e. volcano, humans, grazing animal, flooding
Term
autogenic succession
Definition
describes a succession where the stimulus for change is an internal one

i.e. soil improvement that allows a new species to develep
Term
How do the characteristics (plant functional type, biomass, density, plant morphology/longevity etc.)
change as succession progresses?
Definition
?????
Term
relay floristics
Definition
In succession, a site begins with two pioneer species. As the forest the species that grows best w/o much shade will prosper. After this species is established the shade tolerant species will eventually take over as it receives more shade underneath the canopy of the other species and prospers.
Term
initial floristic composition?
Definition
suggests that species composition of vegetation following disturbance is determined by the propagules that exist on the site at the time of the disturbance and those which arrive early in the process of stand development. Changing species dominance over time results from differential growth and development of species present
Term
What is/are the main difference(s) between relay floristics and initial floristic composition?
Definition
The initial floristic composition will be a combination of the plants/seeds that were left after the disturbance events. Eventually plants more fit for the area will take over.
Term
R-Species (ruderal)
Definition
weedy species, most energy goes to reproduction
Term
K-Species
Definition
(Late succession species)tolerant, good competitors, tolerates shade, perennial
Term
What ingredients necessary for fire are present?
Definition
Wildfires occur when the necessary elements of a fire triangle intersect: an ignition source is brought into contact with a combustible material such as vegetation, that is subjected to sufficient heat and has an adequate supply of oxygen from the ambient air.
Term
Why does fire frequency (the number of fires over time in a given area) or fire return interval (time
between successive fires) vary with latitude and elevation? How do the characteristics of the vegetation
change associated with shifts in elevation/latitude?
Definition
Higher elevation/latitude = colder temps, less moisture, snow doesn't melt. Tree lines will grow up to the point where the environment can support tree life.

edge of treeline will also normally be warped from wind/lack of protection from elements
Term
What types of services are provided free of charge by ecosystems/species?
Definition
Clean drinking water, decomposition of waste, pharmaceuticals, energy
Term
What is colony collapse disorder and what species/organism is being impacted? Why is this a problem?
Definition
phenomenon in which worker bees in a hive suddenly disappear,(European honey bee) it is significant because bees pollinate many different crops
Term
How valuable are ecosystem services?
Definition
Very; clean water, decomposition of waste, pharmaceuticals
Term
How are ecologists beginning to convince people that ecosystem services are important?
Definition
?????
Term
How does the Sixth Great Extinction differ from the previous five?
Definition
large spatial extent, impacting more organisms, human driven
Term
Why did some large organisms go extinct in North America around 10,000 years ago while others
survived?
Definition
human migration, rapid climate change (warming), hyperdisease (disease brought by humans that had a large effect on mammals 100 lbs +)
Term
HIPPO/HICOPP
Definition
Habit loss, Invasive species, populations (over population), pollution, over-consumption,climate change
Term
Linnaean Shortfall - what is it and what makes it problematic
Definition
Describes the difference between known species and species that exist. Most taxonomists live in cold climates; therefor only organisms in cold areas are discovered/observed
Term
Centilenan Extinctions
Definition
extinctions of unknown species
Term
How many species are on earth that we know of (named) and how many species do we think exist?
Definition
1.7 million now named, 10-25 million estimated
Term
What is the background rate of extinctions and how does this differ from today?
Definition
10-100 species a years, now it is 30,000 species per year
Term
Pleistocene Overkill Hypothesis
Definition
about 14,000 years ago ancestors of native americans entered North America where the large predators had no previous interactions w/ humans and didn't see them as a threat which lead to over hunting to the point of extinction
Term
What is meant by the term minimum viable population and how is it defined?
Definition
minimum amount of organisms needed to exist w/o facing extinction from natural disasters, environmental, or genetic stochasticity (randomness)
Term
What are four sources of uncertainty that can influence small populations?
Definition
Quammen reading ?????
Term
Why are invasive species so much more common today than they have been in the past?
Definition
Human need to control environment - this wasn't a concern in the past (planting of gardens, introducing new species)
Term
How do we get invasive species (that is, what are main the reasons we have invasive species). You should
be able to provide an example species for each category.
Definition
Deliberate introductions - economic reasons, Asian carp and Nutria

Aesthetics - people moving and bringing familiar plants with them

biological control - cane toad, using one species to try and keep another species under control (usually doesn't work)

Accidental species introduction - boats moving from lake to lake w/o cleaning off the bottom of boat
Term
What are some possible ecosystem and species level traits that lead to successful invaders?
Definition
low amount of competitors/predators

short generation times/produce many offspring; helps w/ dispersal

broad niche

community vulnerability

underutilized niches
Term
What is EICA?
Definition
Evolution of increased competitive ability - invasive species are not initially at an advantage, after a while they are able to take advantage of unused resources.

natural selection favors the reallocation of resources
Term
What are some explanations for how some organisms have become invasive? Examples?
Definition
????
Term
Why is it so hard to generalize concerning invasive species?
Definition
Unsure of the effects they will have in predation and competition....????
Term
If dispersal is a natural process, how are invasive species any different? What’s different today?
Definition
Human interaction w/ dispersal???
Term
Joseph Fourier
Definition
1824; Given we have constant sunlight on the Earth, why isn’t it constantly heating up
Discovered that the atmosphere traps (and releases) energy
Term
John Tyndall
Definition
1862; Discovers that particular gasses block radiation
Changes in concentration of ggases can change temperature
CO2
Term
Suante Ahnehnius
Definition
1896;Published the first calculation of Earth’s temp if Co2 were doubled
-5 degrees C
Term
Guy Steward Callendar
Definition
1938; Discovered first evidence of a temperature increase
Related to concentrations to CO2 in the the atmosphere
Term
How does the greenhouse effect work? What are the main gases that trap outgoing radiation?
Definition
CO2 and radiatively important trace (rits) trap out going infrared energy

CO2 and GHG’s are increasing
-200 parts per mil in 1900
-384 ppm today
-Methane: 25 more effecteive about 150%
-N2O (Nitrous oxide) 300 x Better at trapping energy
-Up 20%
Term
Why are CO2 and methane rising?
Definition
Humans - use of fossil fuels....more?
Term
What is the IPCC? Who comprises it and what do they do?
Definition
International Panel on Climate Change; evaluates the risk of climate change caused by human activity. Don't actually write anything, just summarize and approve based on vote
Term
What do climate models that use only natural forcing agents depict compared with models that incorporate
anthropogenic greenhouse gas emissions?
Definition
??????
Term
Of all the things that influence temperatures, which have the largest impact (see slide from 12/03:
Attribution of Warming).
Definition
????? We didn't have class on 12/3, I can't find this slide
Term
What is the atmospheric concentration of CO2 today? How does this compare with the past and how do we
know what the concentrations were in the past?
Definition
384 parts/million today; 200 parts/million in 1900. How do we know?
Term
What characteristics of warming temperatures today appear to be different from warm periods of the past
(hint: think rate and area impacted).
Definition
Change is much more rapid and widespread
Term
How does climate change impact ecosystems?
Definition
force certain species out of their habitat while others flourish, may cause a mass extinction event as snow and water levels continue to change
Term
National Academy of Sciences
Definition
perform an unparalleled public service by bringing together experts in all areas of science. address critical national issues
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