Card Set Information

2011-05-15 15:39:06

Final Exam
Show Answers:

  1. dispersal
    the movement of individuals away from their areas of origin or away from centers of high population density
  2. removing sea urchins resulted in:
    greater seaweed coverage
  3. macroclimate
    climate patterns on the global, regional and local level
  4. microclimate
    very fine climate patterns, like under a log or within a certain lake
  5. in the Northern hemisphere, ___________ facing slopes receive more sunlight than ___________ facing slopes
    southern = more sunlight than northern
  6. photic zone
    top most layer of water, where there is sufficient light for photosynthesis
  7. aphotic zone
    little light penetrates
  8. benthic zone
    basically the "ground" of any water environment; made up of sand & organic/inorganic sediments; occupied by communities of organisms called benthos, that feed on detritus (dead organic matter)
  9. abyssal zone
    the portion of the benthic zone that lies between 2,000 and 6,000 m below the surface
  10. lake; also know the distances from shore
  11. marine, same, know it
  12. Tropical Forest
    rain forests = constant rainfall, while in tropical dry forests precipitation = seasonal; vertically layered and intense light competition; have millions of animal species, including many not yet described
  13. Desert
    low/variable precipitation; can be hot or cold; plants are adapted for heat, desiccation tolerance, water storage, and reduced leaf surface area; many animals are nocturnal
  14. Savanna
    seasonal precipitation/temperature; grasses and forbs make up most of ground cover; wildebeests, zebras, lions, and hyenas
  15. seasonal climate with cool/rainy winters and hot dry summers; has shrubs, small trees, grasses, and herbs; many plants adapted to fire & drought; animals = amphibians, birds and other reptiles, insects, small mammals and browsing mammals
  16. temperate grasslands
    found on many continents; cold winters and wet hot summer; plants = grasses and forbs, and are adapted to droughts and fire; mammals = large grazers/small burrowers
  17. northern coniferous forest, (ex. rocky mountain nat. park in colorado)
    taiga; extends across northern North America and Eurasia; largest terrestrial biome on Earth; long cold winters and hot summers
  18. Temperate Broadleaf Forest (smokey mountains)
    cool winters, humid/ hot summers; year round precipitation falls year round; rain and snow has vertical layers dominated by deciduous trees in the Northern Hemisphere and evergreen eucalyptus in Australia
  19. Tundra
    covers expansive areas of the Arctic; alpine tundra exists on high mountaintops at all latitudes; cold long winters and cool summers; precipitation varies; has a permanently frozen layer of soil = permafrost; there's some mineral and oil extraction
  20. Oligotrophic lakes
    oxygen-rich and nutrient-poor
  21. eutrophic lakes are
    nutrient-rich and often depleted of oxygen if ice covered in winter
  22. immigration vs. emigration
    the influx of individuals from other new areas , while emigration is the movement of individuals out of a population
  23. life table
    age-specific summaries of the survival patterns of a population
  24. cohort
    a group of individuals of the same age
  25. 3 types of survivorship curves:
    • Type I: flat at the start (low deaths in early/middle age), then steep drop at old age; humans/large mammals
    • Type III: steep drop at the start, high death rates for young, but then flattens out to show that those who survive young death live (oyster)
    • Type II: intermediate curves, constant death rate over organisms life (squirrels; just a straight line down)
  26. big-bang reproduction/semelparity
    when an organism produces all ofspring in one event; ex: salmon, reproduce once in large reproductive events; ticks reproduce once and then die
  27. repeated reproduction/iteroparity
    reproduction than occurs more than once over a period of years (mammals, humans)
  28. organismal ecology
    focuses on the interaction of a single species with its environment. (Structure, physiology, behavior, etc.)
  29. landscape ecology
    focuses on how spatial arrangement of habitat types affects the distribution and abundance of organisms and ecosystem processes
  30. Ecotones
    the area of transition between biomes; get something in between when transferring between two
  31. random dispersion
    when the position of individuals is independent of other individuals, is rare. It occurs in the absence of strong attractions or repulsions among individuals. Ex: dandelions (cause seeds are blown by wind)
  32. Life history
    • traits that affect an organism’s schedule of
    • reproduction and survival; made up of 3 variables 1) age of first reproduction
    • 2) frequency of reproduction
    • 3) number of offspring per reproductive episode
  33. changes in population size during a time interval =
    number of births or immigrations MINUS (-) number of deaths or emigrations
  34. per capita birth rate (b)
    • the number of offspring produced per unit time by an average member of the population;
    • b = number of births in a population / number of individuals in the population
  35. Per capita death rate (d)
    • expected number of deaths per unit time (using something like the cohort study) in a population
    • of any size;
    • d = number of deaths in a population / number of individuals in the population
  36. per capita rate of increase (r)
    r = b – d; if r > 0 population growing; opposite; and if r = 0 there is no population growth
  37. logistic population growth model
    describes a population as it reaches the carrying capacity (k), which is the maximum population size that a particular environment can sustain
  38. Density Dependent
    birth or death rate vary because of density; as density increases, either reproduction slows or mortality increases
  39. population dynamics
    study of how interactions between biotic and abiotic factors influence variations in population size
  40. Ecosystem
    all organisms in a given area as well as the abiotic factors with which they interact; one or more communities and the physical environment around them; ecosystem ecology focuses on energy flow and chemical cycling within ecosystems
  41. only a small percentage of the solar radiation that makes it to the Earth’s surface will be used for photosynthesis because:
    much is absorbed or reflected by other surfaces (soil, rock, ice...); and only certain wavelengths of the solar radiation is actually used for photosynthesis, about 1%
  42. gross primary production (GPP)
    the total primary production of an ecosystem; the amount of light energy converted to chemical energy by photosynthesis per unit time; measured using carbon per area per unit time
  43. net primary production (NPP)
    the gross primary production of an ecosystem minus the energy used by the producers for cellular respiration; amount that’s converted to biomass; NOT the same as the total biomass (which can be accumulated over multiple years) or standing crop; essentially GPP - energy used by primary producers (for respiration, R); important because it represents the amount of energy available to consumers
  44. you gotta go back to chapters 53 and 54
  45. tropical rainforests have ____ NPP and deserts or arctic tundras have ___ NPP
    high; low
  46. we measure NPP using:
    harvesting (only tells you above ground NPP), allometric equations (especially forestry), correlate it to leaf biomass (as it increases so does NPP), LAI (leaf area index, # of leaves on the ground), remote sensing, physical and empirical models
  47. remote sensing
    because chlorophyll (and therefore vegetation) uses visible light more often than near-infared, differences in light reflection can be used to estimate NPP; the larger the difference (or number), the more vegetation there is
  48. animals with the highest efficiencies are the lowest on the hierarchy:
    are therefore most likely primary producers
  49. CO2/carbon cycle
    used by primary producers to create the organic matter used by consumers; comes from fossil fuels, soils, biomass, ocean, the atmosphere and sedimentary rock
  50. GtC
    = a gigaton of carbon = 1 billion metric tons of carbon or 109
  51. PgC
    = petagram = 1015 grams = GtC?????
  52. uptake of carbon by oceans changes based on uptake by atmosphere;
    increase in atmosphere means there's an increase in the amount that is taken up by the oceans
  53. CO2 is a greenhouse gas
    as it increases it’s correlated with the temperature so that increases as well; however there’s more variability with temperature change
  54. actual evapotranspiration
    the annual amount of water transpired by plants and evaporated from a landscape; increases with the amount of precipitation in a region and solar energy available
  55. secondary production
    the amount of chemical energy in consumers' food that is converted to their own new biomass during a given time period
  56. production efficiency
    percentage of energy stored by an organism that ISN'T used for respiration or feces or whatever
  57. trophic efficiency
    percentage of production transferred from one trophic level to the next; are ALWAYS less than production efficiencies (b/c takes into account energy lost through feces/respiration AND the energy not passed on to the next trophic level); usually around 10%
  58. short turnover time means:
    SMALL standing crop compared to production
  59. main nutrient lost through agriculture:
  60. critical load
    the amound of added nutrient (usually phosphorous or nitrogen) that can be absorbed by plants without damaging ecosystem integrity
  61. three sources of human nitrogen:
    fossil fuels, fertilizers and industrial, and N-fixation in agroecosystems (F.F.N.); burning fossil fuels, producting of fertalizer AND soy beans (cause they’re nitrogen fixing) ALL impact the nitrogen cycle
  62. dead zone
    low-oxygen areas in the oceans that occur near inhabited coastlines, where aquatic life is very concentrated; also present in large lakes
  63. anthropogenic (human impact) precursors to acid precipitation:
    SO2 (sulfate), NOx and NH3 (nitrate); specifically electric power generation that relies on burning fossil fuels (like coal), cars, as well as animal waste and fertilizers (primary source of NH3)
  64. Community
    a group of populations of different species living close enough together to interact
  65. Community Ecology
    the study of how interactions between species affect community structure and organization
  66. Interspecific interactions
    interactions with individuals of other species LIKE competition, predation, herbivory, or symbiosis
  67. competition
    when individuals of different species compete for a resource that limits growth or survival; ex. plants will compete for sunlight, water, and nutrients (resource must be limited); neither species benefits!
  68. competitive exclusion concept
    when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population
  69. resource partitioning
    differentiation of niches which enables similar species to coexist; ex: species of Anolis lizards live in close proximity & eat same insects and small arthropods BUT! have different perch preferences
  70. ecological niche
    the sum of a species’ use of the biotic and abiotic resources in its environment (their "profession"); species can coexist if there are one or more differences in their niche
  71. fundamental vs. realized niche
    fundamental = the niche potentially inhabited by a species; realized = the portion of the fundamental niche that the species actually occupies; fundamental niche can be identified by removing competitors; ex: barnacle species! (chthamalus and balanus)
  72. character displacement
    the tendency for characteristics to be more divergent in sympatric populations that compete for resources (allopatric = geographically separate, sympatric = geographically overlapping)
  73. cryptic coloration
    camouflage; makes the prey hard to see; ex: canyon tree frog
  74. aposematic coloration
    warning coloration; indicates to predators that this is not good food; ex: poison dart frog (so it's coloration that ACTUALLY indicates danger)
  75. batesian mimicry
    is when a harmless or palatable species mimics an unpalatable or harmful model; ex: when a hawkmoth larva imitates a (poisonous) parrot snake
  76. müllerian mimicry
    when two or more unpalatable (yucky) species resemble each other; ex: bee and yellow jacket!
  77. most herbivores are:
  78. symbiosis
    when individuals or two or more species live in direct and intimate contact with each other; 3 types are: Parasitism, Mutualism, Commensalism (PMC)
  79. mutualism
    a symbiotic interaction that benefits both species; obligate mutualism = at least one species can not survive without the other; facultative mutualism = both species can survive on their own
  80. trophic structure
    the feeding relationships between organisms
  81. dynamic stability hypothesis
    long food chains are less stable; population fluctuations at lower trophic levels are magnified at higher levels and could cause local extinctions of top predators
  82. dominant species
    most abundant species, or have the highest biomass in a community; become the dominant species by 1) being the best at exploiting limited resources (water, nutrients) or 2) are the best at avoiding predators or disease
  83. keystone species
    not most abundant species but one that exerts strong control on community structure because of a necessary ecological role; ex: how when the otter population decreases the sea urchin (their food) population increases and therefore kelp can't grow
  84. foundation species
    exert their influence by causing physical changes in an environment; called ecosystem 'engineers'; ex: beavers, who can easily change a landscape
  85. Bottom-Up vs. Top-Down Models of Community Organization
    Bottom-up model: mineral nutrients influence community organization by controlling plant or phytoplankton numbers, which in turn control herbivore numbers, which in turn control predator numbers

    Top-down model: predation influences community organization by controlling herbivore numbers, which in turn control plant or phytoplankton numbers, which in turn control nutrient levels; also called the trophic cascade model
  86. intermediate disturbance hypothesis
    concept that moderate levels of disturbance can foster greater species diversity than low or high levels of disturbance
  87. ecological succession
    transition in the species composition of a community following a disturbance; the establishment of a community in an area virtually barren of life
  88. primary succession
    type of ecological succession that occurs in an area where there were originally no organisms present and where soil has not yet formed
  89. secondary succession
    type of succession that occurs where an existing community has been cleared by some disturbance that leaves the soil or substrate intact; ex. the reforestation of abandoned agricultural land
  90. zoonotic pathogens
    disease-causing agents transmitted to humans from other animals;3/4 of today’s emerging human diseases are caused by them
  91. reservoir competence
    how many animals become infected by a certain pathogen (compare to the density of the pathogen and such); ex: mice are highly reservoir competent in terms of lyme disease