ecology-Biosphere part 2

  1. Hot deserts
    • sparse population of plants and animals
    • high temp, low water availability
    • 30 degrees N and S- hadley cells create zones of high pressure inhibiting formation of storms
    • major zones- sahara, afacma, chihuahaun
    • succulent steams, drought deciduous shrubs and grasses
    • high diversity
  2. Stem Succulence
    • can store water in tissue to help continue to fnx during dry periods
    • ex: cactus and Euphorb
  3. Desertification
    long term drought in association with sustainable grazing practices can result in loss of plant cover and soil erosion
  4. Temperate Grasslands
    • latitudes 30-50 degrees N - plains
    • undulating expanses of grass dominated landscape
    • warm, moist summers and cold dry winters
    • frequent fires prevent trees
    • agriculture
    • most human-influenced biome on earth
  5. Temperate Shrublands and Woodlands
    • woodlands(open canopy of short trees)
    • Mediterranean-type climate: occuring at lattitudes 30-40 Nand S
    • Characterized by asunchrony btween precipitation and summer growing season
    • rain=winter, hot/dry=spring, summer, and fall
    • evergreen shrubs and tree, leaves allow to be active during cooler/wetter, and low nutrient requirement b/c no need for new leaves
    • sclerophyllous leaves- tough, leathery and stiff- need fire- rain shadow effects and seasonally cold climates
  6. Temperate Deciduous Forest
    • areas with enough rainfall to support tree growth and to support loss of nutrients during fall
    • at 30-50 degrees N on east and west edges of Eurasia and E.N.A.
    • Oak, Maple, and Beech trees; vertical structure canopy trees as well as shorter trees, shrubs and ferbs below canopy- species diversity not as high as tropical rainforest- fires not important
    • agriculture in past- abandoned- reforestation
  7. Temperate Evergreen Forest
    • precipitation variesn( high rain=45-50 on west coast= temperate rainforest)
    • found on nutrient-poor soils- temperate evergreen
    • regular fires of intervals of 30-60 years
    • temperate evergreen found 30-50 degree N and S
    • north= neddle-leaved conifers such as pines, junipers
    • south= southern beaches, eucalypts, chilean cedar and podocarps
    • reduced occurance of fires in N.A. resulting in more intense fires when they occur and high pest and pathogens
  8. Boreal Forest
    • Above 50-65.5 N min temp of -50 C are common
    • also know as Taiga- composed of coniferous species including spruce, pines, and larches
    • in maritime location deciduous birch
    • permafrost: subsurface soil layer that remains frozen year-round for at least 3 years
    • largest biome in area
    • rate of plant growth higher than the rate of decomposition
    • summer=dry= fires
    • slow rate of decomposition b/c of permafrost- meaning large level of organic material
  9. Tundra
    • trees cease to be the dominant vegatation at 65 degrees
    • occurs primarily in the Artic and can be found on the edges of the Antartic peninsula
    • characterized by sedges, forbs, grasses, and low growing shrubs such as heaths, willows, and birchens
    • plants go dormant during winter to survive
    • permafrost allow for moist soil
    • wolves
  10. Polygons
    • thawing and freezing of soil results in shortening of soil materials according to thier texture
    • surface with up raised rims and depressed centers
  11. Mountains
    • 1000m up= 6.4 degrees C lower
    • compared to a distance of 1400 km or 13 degree change in latitude
    • slope and proximity tp strems affect the climate
    • grassland at base, but to pine savannas on initial slope-> denser strands of mixed pine-aspen forests-> spruce and fir trees-> diminutive plants such as sedges, grasses
  12. Lotic
    ecosystem made of descending water converging into progressively larger streaams and rivers
  13. Riffles
    fast moving portions of the stream flowing over coarse particles on the stream bed, which increases oxygen input into the water
  14. Pools
    deeper, water flows more slowly over a bed of fine sediment
  15. Benthic
    • bottom of the stream
    • invertebrates that consume dentritus: dead organic material
    • insect larvae, crustaceans
    • detritus derived from the littoral and pelagic serves as an energy serves as an energy source for animals, fungus and bacteria
  16. Hyporheic Zone
    • zone below and adjacent to the stream, where water movement still occurs either from the stream or from ground water moving into the stream
    • rotifers, copepods and insects
  17. River Continuum Concept
    • As a stream flows downslope and bigger in size the input of detritus from the vegetation adjacent to the stream (riparian vegetation) low relative to the volume of water, the particle size in stream bed smaller, from boulder and coarse rock to fine sand
    • importance of terrestrial detritus is higher at stream sourse, shredders upstream-> collections downstream
    • concept applies best to temperate river systems but not well in rivers with high concentrations of organic substances
  18. Lentic
    • lakes and other still water
    • occur where natural depressions have filled with water or where humans have damned rivers into reservoirs
  19. Formation of lakes and ponds
    • form when glaciers gouge out depressions and leave behind natural dams of rock debris
    • when large chuncks of glacial ice breaks off, becomes surrounded by glacial debris and melts
    • when meandering rivers cease to flow through a former channel, leaving a section stranded (oxbow lake)
    • biological orgin in addition to reservoirs include beaver clams and animals wallows
  20. Pelangic Zone
    • open water
    • plankton: small often microscopic organisms that are suspended in the water
  21. Photic Zone
    • surface layer of water where there is enough light for photosynthesis
    • phytoplankton: photosynthetic plankton
  22. Littoral Zone
    • nearshore zone where the photic zone reaches to the lake bottom
    • macrophytes join with floating and benthic phytoplankton to produce energy
    • fish and zooplankton also occur
  23. Tides
    • generated by the gravitational attraction between Earth and the moon and the sun
    • magnitude of the tidal range varies greatly among different locations b/c it is related to shoreline morphology and ocean bottom structure
  24. Estuaries
    • the junction of a river with the ocean
    • characteristics- variations in salinity associated with the flow of fresh water into ocean
    • many fish species spend thier juvenile stages in estuaries (shellfish)
    • highly threatened by water pollution, nutrients from upsteam agriculture sources can cause local dead zones
  25. Salt Marshes
    • terrestrial sediments carried to shorelines by rivers
    • dominated by emergent vascualr plants, including grasses, rishes, and broad-leaved herbs
    • input of rivers increase productivity
    • highest portions of the marshes have the highest level of salinity b/c low flooding
    • fish crabs birds mammals
  26. Mangrove Forests
    • shallow coastal estuaries and nearby mudflats in tropical and subtropical regions, inhabited by salt tolerant evergreen trees and shrubs
    • roots trap mud and sediments and modify the shoreline
    • manatees, crab-eating monkeys, fishing cats, and monitor lizards
  27. Rocky Intertidal Zones
    • provide a stable substrate to which a diverse collection of algae and animals can anchor themselves to keep from being washed off
    • between the high and low tide-> organisms are arranged based on thier tolerance for temp, salinity, desiccation(drying out), sessile(fixed)
  28. Sandy Shores
    • provide no stable anchoring surface, and the lack of attached seaweeds limits the supply of potential food for herbvorous animals
    • beneath the sand, clams, seaworms, mole crab
    • smaller organisms polychaete worms, hydroids live among the grains of sand
  29. Coral Reefs
    • warm, shallow ocean water, corals live in association with algal partners
    • corals obtain energy from grazers and nutrients
    • extract calcium carbonate
    • grow at slow rate, millimeters per year
    • many species
    • human threaten corals, fishing, pollutants, temperatures
    • bleaching: losing algae partners
    • causes rise in CO2 in atmosphere
  30. Kelp Beds
    • in clear shallow (<15m) temperate ocean water
    • large brown algae
    • specialized tissues. leaves(fronds), stems(stipes), roots(holdfast)
    • sea urchins, lobsters, mussels, abalones, sea otters
  31. Seagrass Beds
    • flowering plants (<5m)
    • found in subtidal marine sediments composed of mud or fine sand
    • reproduce by vegetative growth
  32. Nekton
    • swimming organisms capable of overcoming currents; cephalopods, fishes, sea turtles, and mammals
    • pelagic zone
    • photosynthesis= phytoplankton (green algae, diatoms, dinoflagellates, and cyanobacteria)
    • Zooplankton
Card Set
ecology-Biosphere part 2
biosphere terms