BioGeo Test 3 – Flashcards
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Succession |
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predictable and orderly changes in the composition or structure of an ecological community. |
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Primary Succession |
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Succession that result from the formation of new soil (usually lava flow or retreat of glacier) |
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Secondary Succession |
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Succession started by an even such as a fire or hurricane that reduced an established population to a smaller population of species |
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ecological management |
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the management of human activities so that ecosystems, their structure, function, composition and physical chemical and biological processes that shaped them continue to function. |
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Explain how ecological and natural area management can be thought of as the manipulation of successional processes, disturbances, or both. |
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Human influence on an area disrupts the natural process of succession (prevention of forest fires) |
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Allogenic Succession |
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describes a succession where the stimulus for change is an external one. i.e. volcano, humans, grazing animal, flooding |
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autogenic succession |
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describes a succession where the stimulus for change is an internal one i.e. soil improvement that allows a new species to develep |
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How do the characteristics (plant functional type, biomass, density, plant morphology/longevity etc.) change as succession progresses? |
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????? |
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relay floristics |
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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. |
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initial floristic composition? |
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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 |
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What is/are the main difference(s) between relay floristics and initial floristic composition? |
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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. |
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R-Species (ruderal) |
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weedy species, most energy goes to reproduction |
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K-Species |
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(Late succession species)tolerant, good competitors, tolerates shade, perennial |
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What ingredients necessary for fire are present? |
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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. |
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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? |
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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 |
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What types of services are provided free of charge by ecosystems/species? |
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Clean drinking water, decomposition of waste, pharmaceuticals, energy |
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What is colony collapse disorder and what species/organism is being impacted? Why is this a problem? |
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phenomenon in which worker bees in a hive suddenly disappear,(European honey bee) it is significant because bees pollinate many different crops |
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How valuable are ecosystem services? |
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Very; clean water, decomposition of waste, pharmaceuticals |
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How are ecologists beginning to convince people that ecosystem services are important? |
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????? |
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How does the Sixth Great Extinction differ from the previous five? |
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large spatial extent, impacting more organisms, human driven |
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Why did some large organisms go extinct in North America around 10,000 years ago while others survived? |
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human migration, rapid climate change (warming), hyperdisease (disease brought by humans that had a large effect on mammals 100 lbs +) |
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HIPPO/HICOPP |
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Habit loss, Invasive species, populations (over population), pollution, over-consumption,climate change |
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Linnaean Shortfall - what is it and what makes it problematic |
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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 |
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Centilenan Extinctions |
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extinctions of unknown species |
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How many species are on earth that we know of (named) and how many species do we think exist? |
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1.7 million now named, 10-25 million estimated |
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What is the background rate of extinctions and how does this differ from today? |
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10-100 species a years, now it is 30,000 species per year |
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Pleistocene Overkill Hypothesis |
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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 |
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What is meant by the term minimum viable population and how is it defined? |
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minimum amount of organisms needed to exist w/o facing extinction from natural disasters, environmental, or genetic stochasticity (randomness) |
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What are four sources of uncertainty that can influence small populations? |
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Quammen reading ????? |
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Why are invasive species so much more common today than they have been in the past? |
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Human need to control environment - this wasn't a concern in the past (planting of gardens, introducing new species) |
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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. |
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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 |
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What are some possible ecosystem and species level traits that lead to successful invaders? |
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low amount of competitors/predators short generation times/produce many offspring; helps w/ dispersal broad niche community vulnerability underutilized niches |
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What is EICA? |
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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 |
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What are some explanations for how some organisms have become invasive? Examples? |
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???? |
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Why is it so hard to generalize concerning invasive species? |
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Unsure of the effects they will have in predation and competition....???? |
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If dispersal is a natural process, how are invasive species any different? What’s different today? |
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Human interaction w/ dispersal??? |
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Joseph Fourier |
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1824; Given we have constant sunlight on the Earth, why isn’t it constantly heating up Discovered that the atmosphere traps (and releases) energy |
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John Tyndall |
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1862; Discovers that particular gasses block radiation Changes in concentration of ggases can change temperature CO2 |
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Suante Ahnehnius |
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1896;Published the first calculation of Earth’s temp if Co2 were doubled -5 degrees C |
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Guy Steward Callendar |
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1938; Discovered first evidence of a temperature increase Related to concentrations to CO2 in the the atmosphere |
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How does the greenhouse effect work? What are the main gases that trap outgoing radiation? |
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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% |
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Why are CO2 and methane rising? |
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Humans - use of fossil fuels....more? |
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What is the IPCC? Who comprises it and what do they do? |
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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 |
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What do climate models that use only natural forcing agents depict compared with models that incorporate anthropogenic greenhouse gas emissions? |
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?????? |
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Of all the things that influence temperatures, which have the largest impact (see slide from 12/03: Attribution of Warming). |
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????? We didn't have class on 12/3, I can't find this slide |
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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? |
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384 parts/million today; 200 parts/million in 1900. How do we know? |
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What characteristics of warming temperatures today appear to be different from warm periods of the past (hint: think rate and area impacted). |
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Change is much more rapid and widespread |
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How does climate change impact ecosystems? |
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force certain species out of their habitat while others flourish, may cause a mass extinction event as snow and water levels continue to change |
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National Academy of Sciences |
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perform an unparalleled public service by bringing together experts in all areas of science. address critical national issues |