Chapter 52 - An Introduction To Ecology And The Biosphere Flashcards
Define ecology
The scientific study of the interactions between organisms and the environment (other organisms as well as physical aspects of an organism’s surroundings)
What is organismal ecology concerned with?
How an organism’s structure, physiology, and behavior meet the challenges posed by its environment
Describe population ecology
Analyzes factors that affect population size and how and why it changes through time
Describe community ecology
Examines how interactions between species, such as predation and competition, affect community structure and organization
Define ecosystem
An ecosystem is the community of organisms in an area and the physical factors with which those organisms interact
Define community
A group of populations of different species in an area
Describe ecosystem ecology
Emphasizes the energy flow and chemical cycling between organisms and the environment
Define landscape
A mosaic of connected ecosystems
Describe landscape ecology
Focuses on the factors controlling exchange of energy, materials, and organisms across multiple ecosystems
Define biosphere
The global ecosystem - the sum of the planet’s ecosystems and landscapes
Describe global ecology
Examines how the regional exchange of energy and materials influences the functioning and distribution of organisms across the biosphere
What is climate and how does it differ from weather?
The long term prevailing weather conditions in a given area; its key components include temperature, precipitation, sunlight and wind
Weather is short term
Describe microclimate and it’s difference from macro climate.
Very fine, localized patterns in climate conditions vs. the general climate of a large area
What is climate affected by?
Seasonality, large bodies of water, and mountains
Describe north vs south facing slopes in the northern hemisphere
South facing is drier and the north facing is more moist because of the angle of the sun; opposite in Southern Hemisphere
Where are the strongest winds?
The trade winds are 30 degrees above and below the equator
Where are rain shadows located?
The leeward side of the mountains
Define biomes
Major life zones characterized by vegetation type (terrestrial biomes) or physical environment (aquatic biomes) defined by the types of plants that live there
What is a major factor of determining the locations of terrestrial biomes and why?
Climate is very important in determining why terrestrial biomes are found in certain areas because they affect the types of plants
What is an ecotone?
The area of degradation of other biomes into each other
Describe vertical layering
An important feature of terrestrial biomes consisting of an upper canopy, lower tree layer, shrub understory, ground layer of herbaceous plants, forest floor, and root layer
Define disturbance
An event that changes a community ie storm, fire, human activity
Describe tropical rainforests
Equatorial and subequatorial regions
Constant rainfall in rainforests and seasonal rainfall in dry forests
High temperature year round (stable environment for more speciation)
Most vertical layering
Harmed by rapid human growth
Describe deserts
Bands 30 deg N/S of equator and in interior of continents
Low&variable precipitation (<30cm/yr)
Temp variable by day and season
Specialized vegetation and animals depending on desert type
Common animals: reptiles many nocturnal, few mammals bc no water
Natural disturbances are common (floods)
Where are hot deserts commonly located?
At lower altitudes
Where are cold deserts commonly located?
Interior of continents
High altitudes
Areas with little precipitation
Describe the coastal desert (chaparral = Mediterranean climate)
Very few places in the world
Western sides of continents with cool ocean currents
Cool, wet winters and warm, dry summers
Adapted to periodic fire and seasonal drought
Vegetation: shrubs and low trees with tough leaves
Harmed by urbanization and ATVs
Describe semi-arid deserts
Similar to coastal but with less rainfall and higher temperatures
Prone to flash floods
Ex. Utah, Arizona, S. Nevada
Describe a Savanna
Grassland scattered with individual trees
Climate shapes biome (rainfall is concentrated with dry season lasting 8-9 mo)
Fires are important
Large grazing and browsing mammals (bc a lot of plants to eat); large predators
Problems: poaching, overgrazing, land clearing/agriculture
Describe the temperate grassland
Precipitation highly seasonal Cold, dry winters and hot, wet summers Dominated by grasslands Adapted to drought and fire Native mammals: large grazers (bison, horses) and small burrowers ( prairie dogs) Most converted to farmland
Describe northern coniferous forest/Taiga/boreal
Largest terrestrial biome on earth (most of Canada and Russia)
Shorter, warmer summers and long, cold winters
Conifers dominate (shape of needle scale like leaves allows snow to fall off and reduces water loss)
Migratory birds
Unstable/cold conditions
Only N. Hemisphere
Describe temperate broadleaf (deciduous) forest
Mainly mid-latitudes in N. Hemisphere
Well defined season w/ summer rain (hot&humid) and winter snow
Well developed vertical layers
Richer soil bc more leafy trees and light (humus)
Small animals dominate
Treats: urbanization and acid rain
Describe the tundra
Tundra = treeless plain Precipitation: mainly snow but not much in arctic Cold winters (-60F) cool summers (50C)
Describe the arctic tundra
Only few species with large populations and lots of insects
Many migratory species (high population oscillations)
Few reptiles and amphibians (cold)
Soil = permafrost
Plants: lichens, poss, low shrubs
Threats: climate change, permafrost = carbon source
Describe the alpine tundra
Soil is well drained
Mountains where trees cannot grow
Plants: low growing shrubs
Mammals: small year round (little migration except elk)
Threats: ski development, air pollution, acid rain, climate change
Define ecological time
The minute to minute time frame of interactions between organisms and the environment
Define evolutionary time
The time frame from generation to generation (long periods of time) that natural selection goes through; can be resulting from ecological time
Define dispersal and how it is different from migration.
The permanent movement of individuals/gametes from origin or from centers of high population density.
Migration is the regular long lasting change in location to areas of good birthing or good food
Define adaptive radiation
Rapid evolution of an ancestral species into a new species that can fill an ecological role ie. Tarwerd to Hawaiian Silversword
