Chapter 52 Flashcards
Ecology
The scientific study of the interactions between organisms and the environment (includes living and non-living elements)
Interactions between organisms and the environment determine the _ of organisms and their abundance.
Distribution
Modern ecology includes _ and _.
Observation; experimentation
Ecologists work at levels ranging from individual organisms to the planet:
- Global ecology
- Landscape ecology
- Ecosystem ecology
- Community ecology
- Population ecology
- Organismal ecology
Climate
The long-term prevailing weather conditions in an area (abiotic)
Four major abiotic components of climate are:
- Temperature
- Precipitation
- Sunlight
- Wind
Macroclimate
Consists of patterns on the global, regional, and landscape level (ex: rainforest)
Microclimate
Consists of very fine patterns, such as those encountered by the community of organisms underneath a fallen log (ex: underneath a fallen log in a rainforest)
Global climate patterns are determined largely by _ and Earth’s movement in space.
Solar energy
The warming effect of the sun causes temperature variations, which drive _ and the circulation of air and water.
Evaporation
The _ at which sunlight hits Earth affects its intensity, the amount of heat and light per unit of surface area.
Angle
The intensity of sunlight is strongest in the _ (between 23.5 degrees north latitude and 23.5 degrees south latitude) where sunlight strikes Earth most directly.
Tropics
Climate is affected by:
- Seasonality
- Large bodies of water
- Mountains
Seasonal variations of light and temperature increase steadily toward the _.
Poles
_ at high latitudes is caused by a tilt of Earth’s axis of rotation and its annual passage around the sun.
Seasonality
Belts of wet and dry air around the _ shift throughout the year with the changing angle of the sun.
Equator
Changing _ patterns affect ocean currents.
Wind
Oceans, their currents, and large lakes moderate the climate of nearby _ environments.
Terrestrial
Currents flowing toward the equator carry _ water from the poles; currents flowing away from the equator carry _ water toward the poles.
Cold; warm
During the day, air rises over warm land and draws a cool breeze from the _ across the land.
Water
As the land cools at night, air rises over the warmer water and draws cooler air from _ back over the water, which is replaced by warm air from offshore.
Land
Mountains affect the amount of _ reaching an area.
Sunlight
In the _, south-facing slopes receive more sunlight than north-facing slopes.
Northern Hemisphere
Every 1,000 m increase in elevation produces a temperature drop of approximately _ degrees C.
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Biomes
Major life zones characterized by vegetation type (terrestrial biomes) or physical environment (aquatic biomes)
_ is very important in determining why terrestrial biomes are found in certain areas.
Climate
Terrestrial biomes are often named for major physical or climatic factors and for _.
Vegetation
Terrestrial biomes usually grade into each other, without sharp _.
Boundaries
the area of intergradation (where one biome ends and the next begins), called an _ may be wide or narrow.
Ecotone (some animals like to seek these out)
Layering of vegetation in all biomes provides diverse _ for animals.
Habitats
The species _ of each kind of biome varies from one location to another.
Composition
Similar characteristics can arise in distant biomes through _ evolution.
Convergent
Cacti in North America and euphorbs in African deserts appear similar but are from different _ lineages.
Evolutionary
Disturbance
An event such as a storm, fire, or human activity that changes a community.
Examples of disturbance:
- Frequent fires can kill woody plants and maintain the characteristic vegetation of a savanna
- Hurricanes create openings in forests that allow different species to grow
In many biomes, even dominant plants depend on periodic _.
Disturbance
Terrestrial biomes can be characterized by:
- Distribution
- Precipitation
- Temperature
- Plants
- Animals
Examples of terrestrial biomes:
- In tropical rain forests, rainfall is relatively constant
- In tropical dry forests, precipitation is highly seasonal
_ plants are adapted for heat and desiccation tolerance, water storage, and reduced leaf surface area.
Desert
In _ grassland, native mammals include large grazers such as bison and wild horses and small burrowers such as prairie dogs.
Temperate
The largest marine biome is made up of _, which cover about 75% of Earth’s surface and have an enormous impact on the biosphere.
Oceans
_ biomes are closely linked to soils and the biotic components of the surrounding terrestrial biome.
Freshwater
Major aquatic biomes can be characterized by their:
- Physical environment
- Chemical environment
- Geological features
- Photosynthetic organisms
- Heterotrophs
Aquatic biomes:
- Lakes
- Wetlands
- Streams
- Rivers
- Estuaries
- Coral reefs
Species _ are the result of ecological and evolutionary interactions through time.
Distributions
Ecological Time
The minute-to-minute time frame of interactions between organisms and the environment
Evolutionary Time
Spans many generations and captures adaptation through natural selection
Both _ and _ factors influence species distribution.
Biotic; abiotic
Biotic factors that affect the distribution of organisms:
- Predation
- Competition
- Mutualism
- Parasitism
- Herbivory (for example, sea urchins can limit distribution of seaweeds)
Abiotic factors affecting the distribution of organisms:
- Temperature
- Water
- Oxygen
- Salinity
- Sunlight
- Soil
