Ecology

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Ecology

• The study of organisms and their interactions

2
Ecology

• Interactions between organisms and the abiotic
  and biotic components of their environment limit
  the distribution of species
• The abiotic components of an environment are the
  nonliving, chemical and physical components
  (temperature, water, sunlight, wind, rocks and
  soil composition)
• The biotic components are the living members
  (parasites and pathogens, as well as predators
  and prey organisms)
• Biogeography is the study of the past and present
  distribution of individual species
• The dispersal of a species can be either uniform,
  random or clumped (which is most common?)

3
Ecosystem

• Refers to the collection of components and
  processes that comprise some defined subset of
  the part of the planet where life occurs
  (biosphere). An ecosystem includes all biotic and
  abiotic components, and their interactions with
  each other, in some defined area, with no
  conceptual restrictions on how large or small
  that area can be
• Climate is the temperature, water
  (precipitation), light and wind in a geographic
  region over a minimum period of 20-30 years it
  can be thought of as the long term average
  weather in an area
• A microclimate is a small-scale climate, for
  example, under a log
• A biome is a major type of ecosystem that
  occupies a broad geographic region, may be either
  aquatic or terrestrial, largely determined by
  climate

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Aquatic Biomes

• Make up 75 of the biosphere
• Classified as either freshwater or marine
• Aquatic biomes display vertical stratification
• Light photic zone (enough light for
  photosynthesis) vs. aphotic zone (not enough
  light)
• Temperature thermoclines are narrow layers of
  fast temperature change that separate a warm
  upper layer from cold deeper waters

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Freshwater Biomes

• Can either be standing water (lakes) or moving
  water (streams rivers)
• Oligotrophic lakes are deep lakes that are
  nutrient-poor, oxygen rich and contain sparse
  phytoplankton (autotrophic floating plant-like
  microorganisms)
• Eutrophic lakes are shallower and they have a
  higher nutrient content, lower oxygen content and
  a high concentration of phytoplankton
• In lakes, communities are distributed according
  to the waters depth
• Littoral zone well-lit, shallow water near the
  shore, contains rooted and floating aquatic
  plants
• Limnetic zone well-lit, open surface water
  farther from shore, contains phytoplankton

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Freshwater Biomes

• Wetlands are areas covered with water deep enough
  to support aquatic plants
• Estuaries are areas where freshwater streams or
  rivers merge with the ocean
• Estuaries have a lot of biodiversity

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Marine Biomes

• The intertidal zone is where land meets water
• Beyond is the neritic zone, the shallow water
  that covers the continental shelves
• In the neritic zone lies the most diverse wholly
  marine ecosystem - the coral reef (a biome
  created by animals (phylum Cnidaria) that secrete
  hard calcium carbonate shells)
• Past the continental shelves is the oceanic zone
• Any open water is called the pelagic zone, and
  the benthic zone lies at the ocean floor
• The abyssal zone refers to very deep benthic
  communities

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Terrestrial Biomes

• Savannah
• Desert
• Tropical forest
• Temperate deciduous forest
• Coniferous forest/taiga/boreal
• Chaparral
• Tundra
• Temperate grassland