BN U4KW1

• Niche: range of some # of environment conditions to which organism is adapted to
• Niche: used to be organisms place in world (Joseph Grinnell) and role (Charles Elton) but reality both and more
• G. Evelyn Hutchins on Niche: "N-Dimensional Hypervolume"
• "N": Number of abiotic/biotic factor that influence reproductive success
• Fundamental niche: potential use of resources by individuals if they were not limited by competition from other species
• Realized niche: Everywhere it does live as a consequences of comp. outcomes with other species
• Joseph Connell B: Niche is equal to it's fundamental niche
• Chthamalus restricted to areas that get moisture during highest part of tide - realized niche much smaller than fundamental niche
• GF Gause - Interspecific Comp. (studied 2 paramecium species)
• Interspecific Competition: the niches of 2 species overlapped they wouldn't coexist (competition)
• Limiting similarity: Max. level of niche overlap between 2 species that allows them to coexist
• Resource partitioning - "Niche shift": Competing species use parts of the habitat that is most comp.
• Character Displacement: An evolution shift in behavior or physiology that results in niche partitioning
• Resource abundance expands species' fundamental niche: scarcity confines them to realized niche due to competition
• Generalists: Species occur in many diff. areas under a wide range of environment conditions (broad niche - wide ecological amplitude)
• Specialists: Species w/specific requirements & occur in habitats w/relatively narrow range of environment conditions (narrow niche)
• Fridley et al. (2007) looked at gen/sp. tendencies in NC, SC, and GA using species co-occurrence instead of direct environment measurements
• Generalists co-occur w/ many species, specialists don't
• Aquatic environment: Constraints, oxygen variation, light stratification, temp. stability, buoyancy, drag, no soil reliance
• Marine: Isotonic, external fertilization
• Freshwater: Hypotonic, internal fertilization water movement coordination
• The habitat selected depends on the characteristics of the organism and its interactions with other living things and nonliving factors within that area.
• Soil: 3D living thing that provides important ecosystem service

  • Decomposition, mitigates flooding, sequesters carbon, medium & provides nutrients for plant growth & shelter seeds
• Hans Jenny soil transformation

  • > S = F (C1, O, R, P, T) "Clorpt"
• Soil forming factors: Climates shapes weathering organisms break rock chem. & mech., relief affects water flow, parent material varies (igneous, metamorphic, sedimentary) all processes occur overtime
• Soil vertically stratified

  • O: Decomp organic matter
  • A: mix of organic material and inorganic
  • B: Inorganic materials
  • C: lumps of unweathered rock
• Soil texture: Sand, silt, and day proportions - lab analysis available now, historically people used to assess by feel & spit test
• NC soil form via leterization, common in humid areas

  • Result: Unisols (old/weathered soil) dominate piedmont
• 13 Soil orders in USA
• Soil's ability to hold water varies (moisture holding capacity), influenced by texture
• Saturated soil is at field capacity
• Water evaporates, plants extract it; wilting pt. is when plants can't extract.

  • available water is between field capacity and wilting point
• Photosynthesis: Sunlight + 6Co2 + 12 H2O -> Carbohydrate + 6O2 + 6 H2O

  • 2 Stages: Light dependent splits water, releases O2, makes NADPH & ATP light independent uses
• C3 uses rubisco, inefficient due to oxygen interference
• C4 uses PEP for efficiency
• CAM separates light phases temporally, opens stomates at night to take up Co2 converts to make acid, releases Co2 during the day
• C4 7 CAM plants (grasses, some shrub, desert plants) benefit from warmer CO2-rich air due to rubisco inefficiency
• Temperature & photosynthesis: Plants vary in temp. tolerance
• Temperature & photosynthesis: July/August Days, the C3 trees in NC close

  stomates to not lose water
• Temperature & Photosynthesis: C4 can photosynthesis at higher temp. but can't sequester much carbon