Chapter 52: An Introduction to Ecology and the Biosphere Flashcards
Ecology
Scientific study of interactions between organisms and the environment
Biosphere
- Global ecosystem
- Sum of all the planet’s ecosystems and landscapes
Global Ecology
Examines how regional exchange of energy and materials influences the functioning & distribution of organisms across the biosphere
Landscapes & Seascapes
Mosaics of connected ecosystems
Landscape Ecology
Focuses on factors controlling exchanges of energy, materials, & organisms across ecosystems
Ecosystem
Community of organisms in an area & the physical factors they interact with
Ecosystem Ecology
Emphasizes energy flow and chemical cycling between organisms and the environment
Community
Group of populations of different species in an area
Community Ecology
Examines how species interactions (i.e. predation) affect community structure and organization
Population
Group of individuals of the same species living in an area
Population Ecology
Analyzes factors that affect population size and how & why it changes through time
Organismal Ecology
- Includes subdisciplines of physiological, evolutionary, & behavioral ecology
- Concerned with how an organism’s structure, physiology, & behavior meet challenges from the environment
Tropics
- Regions between 23.5°N and 23.5°S latitude
- More heat and light per unit of surface area
Climate
- Long-term prevailing weather conditions in a given area
- 4 factors: temperature, precipitation, sunlight, and wind
Macroclimate
Weather patterns on the global, regional, and landscape level
Microclimate
Fine, localized weather patterns
Abiotic
- Nonliving
- Factors include temperature, light, water, and nutrients
Biotic
- Living
- Factors include organisms in an individual’s environment
Biomes
- Major life zones
- Characterized by vegetation type (terrestrial biomes)
- Characterized by physical environment (aquatic biomes)
Climograph
Plot of the annual mean temperature and precipitation in a region
Ecotone
- Region of transition between biomes
- Can be wide or narrow
Canopy
The uppermost level of vegetation in a terrestrial biome
Disturbance
- Event (i.e. storm, fire, human activity) that changes a community
- Organisms are removed
- Resource availability is altered
Tropical Rainforest
- Terrestrial biome
- Relatively high precipitation and temperatures year-round
- High species diversity
Tropical Dry Forest
- Terrestrial biome
- Relatively high temperatures and precipitation overall
- Pronounced dry season
Desert
- Terrestrial biome
- Characterized by very low precipitation
Savanna
- Tropical grassland biome
- Scattered individual trees
- Large herbivores
- Maintained by occasional fires and drought
Chaparral
- Scrubland biome of spiny evergreen shrubs
- Found at midlatitudes along coasts where cold ocean currents circulate offshore
- Characterized by mild, rainy winters and long, hot, dry summers
Temperate Grasslands
- Terrestrial biome
- Exists at midlatitude regions
- Dominated by grasses and forbs
Northern Coniferous Forest
- Terrestrial biome
- Characterized by long, cold winters
- Dominated by cone-bearing trees
Temperate Broadleaf Forest
- Biome located throughout midlatitude regions where there is sufficient moisture to support the growth of large, broadleaf deciduous trees
- Also known as deciduous forest
Tundra
- Terrestrial biome at extreme limits of plant growth
- Northernmost limits = arctic tundra
- High altitudes = alpine tundra (plant forms are limited to low shrubbery or matlike vegetation)
Photic Zone
- Narrow top layer of an ocean or lake
- Light penetrates sufficiently for photosynthesis to occur
Aphotic Zone
- Part of ocean or lake beneath the photic zone
- Light does not penetrate sufficiently for photosynthesis to occur
Pelagic Zone
- Photic and aphotic zones
- Open water component of aquatic biomes
Abyssal Zone
- Deep in aphotic zone
- 2,500 - 6,000 m below the surface
Benthic Zone
- Bottom of all zones
- Sand and organic / inorganic sediments occupied by benthos
Benthos
- Communities of organisms in the benthic zone
- Major source of food is detritus
Detritus
- Dead organic matter
- Rains down from surface waters of photic zone
Thermocline
- Narrow layer of abrupt temperature change
- Separates upper layer from bottom layer by temperature
Turnover
- Semiannual mixing of waters because of changing temperature profiles
- Sends oxygenated water from lake’s surface to the bottom
- Nutrient rich water goes to the surface
- During spring and autumn
Oligotrophic Lake
- Nutrient poor
- Oxygen rich
- Clear lake with few phytoplankton
Eutrophic Lake
- Lake that has a high rate of biological productivity
- Supported by a high rate of nutrient cycling
- Nutrient rich
- Depleted of oxygen in the deepest zone in summer & if covered with ice in winter
Littoral Zone
- In a lake
- Shallow, well-lit waters close to shore
Limnetic Zone
- Well-lit, open surface waters far from shore
- Water is too deep to support rooted aquatic plants
- Variety of phytoplankton live here
Wetland
- Habitat that is inundated with water at least some of the time
- Supports plants adapted to water-saturated soil
Estuary
- Transition area between river and sea
- Sea water flows up the channel during rising tide
- Sea water flows down the channel during falling tide
Intertidal Zone
- Shallow zone of the ocean adjacent to land
- Between the high and low tide lines
- Periodically submerged & exposed by the tides
Ocean Pelagic Zone
- Vast realm of open blue water
- Constantly mixed by wind driven oceanic currents
Coral Reef
- Typically a warm-water, tropical ecosystem
- Dominated by the hard skeletal structures secreted primarily by corals
Marine Benthic Zone
Seafloor below the surface waters of the coastal zone and the offshore, pelagic zone
Neritic Zone
Shallow region of the ocean overlying the continental shelf
Deep-Sea Hydrothermal Vents
- Dark, hot, oxygen-deficient environment associated with volcanic activity on or near the seafloor
- Producers in a vent community are usually chemoautotrophic prokaryotes
Dispersal
Movement of individuals or gametes away from their area of origin or from centers of high population density
Taiga
- Biome characterized by lengthy cold and wet winters
- Has gymnosperms as prominent plant life
- Contains coniferous forests
