Chapter 4- Ecosystems and Communities Flashcards
What is weather?
the day-to-day condition of Earth’s atmosphere at a particular time and place
What is climate?
average, year-to-year conditions of temperature and precipitation in a particular region
What are the factors of climate?
- trapping of heat by atmosphere
- latitude
- transport of heat by winds and ocean currents
- amount of precipitation
What are some of the greenhouse gases in Earth’s atmosphere?
carbon dioxide, methane, water vapor
What is the greenhouse effect?
heat retained by layer of greenhouse gases so that temperatures on Earth remain within a range suitable for life
Why does Earth have three main climate zones?
because of differences in latitude and angle of heating
What are the 3 main climate zones of Earth?
polar, temperate, and tropical
What are the polar zones?
cold areas where the sun’s ray strike Earth at a very low angle; located in areas around in the North and South poles (66.5-90 degrees N&S latitude)
What are the temperate zones?
sit between the polar zones and the tropics; more affected by changing angle of the sun over the course of a year; climate changes depending on season
What are the tropical zones?
neat the equator; receives direct sunlight year round so climate almost always warm; 23.5 N-23.5 S degree latitudes
What 2 factors determine the survival and growth of an organism and the productivity of the ecosystem in which the organism lives?
Biotic and abiotic factors
What can powerfully affect an ecosystem?
Community interactions such as competition, predation, and various forms of symbiosis
Why do ecosystems constantly change?
In response to natural and human disturbances
As an ecosystem changes, what happens to older inhabitants?
They gradually die out
What are biotic factors?
Biological influences on organisms within an ecosystem
What are abiotic factors?
Physical, or nonliving, factors that shape ecosystems
What is a habitat?
The area where an organism lives
What is a niche?
The full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions.
What is a resource?
any necessity of life such as water, nutrients, light, food, or space
What does the competitive exclusion principle state?
no 2 species can occupy the same niche in the same habitat at the same time
What is predation?
an interaction in which one organism captures and feeds on another organism
What is symbiosis?
any relationship in which two species live closely together; there are 3 types: mutualism, commensalism, and parasitism
What happens in mutualism?
both species benefit from the relationship; a type of symbiosis
What happens in commensalism?
one member of the association benefits and the other is neither helped nor harmed; a type of symbiosis
What happens in parasitism?
one organism lives on or inside another organism and harms it; type of symbiosis
What is ecological succession?
series of predictable changes that occurs in a community over time
What is primary succession?
succession that occurs on surfaces where no soil exists
What are pioneer species?
first species to populate an area
What is secondary succession?
when an ecosystem recovers itself to its normal conditions after a disturbance like fires or human disturbances
What is a biome?
a complex of terrestrial communities that covers a large area and is characterized by certain soil and climate conditions and particular assemblages of plants and animals
What is an organism’s tolerance?
their ability to survive and reproduce under conditions that differ from their optimal conditions
What is microclimate?
the climate in a small area that differs from the climate around it
Which biome contains the most species than all the other biomes combined?
tropical rain forest
What biome is hot and wet year-round and has thin, nutrient-poor soils?
tropical rain forest
Which biome grows in places where rainfall is highly seasonal rather than year-round?
tropical dry forest
Which biome is generally warm year-round, alternates wet and dry seasons and its rich soil is subject to erosion?
tropical dry forest
What is a deciduous tree?
a tree that sheds its leaves during a particular season each year
What is another name for tropical savannas?
grasslands
What biome has compact soil, frequent fires set by lightning, and seasonal rainfall?
tropical savanna
What biome is defined as having annual precipitation of less than 25 cm?
desert
Which biome has warm to hot summers, cold winters, moderate seasonal precipitation, fertile soils and occasional fires?
temperate grassland
Which biome is characterized by a semiarid climate and a mix of shrub communities and open woodlands?
Temperate woodland and shrubland
What are chaparral?
communities that are dominated by shrubs
What biome contains a mixture of deciduous and coniferous trees?
temperate forest
What are coniferous trees?
conifers that produce seed-bearing cones and most have leaves shaped like needles
What is humus?
a material formed from decaying leaves and other organic matter that makes soil fertile
What biome is also known as a temperate rain forest?
northwestern coniferous forest
What biome has mild temperatures, abundant precipitation during fall, winter and spring and relatively cool dry summer?
northwestern coniferous forest
Which biome has dense evergreen forests of coniferous trees?
boreal forest
What is another name for boreal forests?
Taiga
Which biome has long, cold winters, short mild summers, moderate precipitation, high humidity and acidic nutrient-poor soils?
taiga or boreal forests
What is permafrost?
a layer of permanently frozen subsoil
What biome is characterized by permafrost?
tundra
What biome has low precipitation, short and soggy summers, long cold dark winters, and poorly developed soils?
tundra
What biome is a moose found in?
taiga or boreal forests
What biome is a caribou found in?
tundra
As you move up a mountain, what happens to its temperature and organisms?
becomes colder and precipitation increases so organisms change
What are aquatic ecosystems determined by?
the depth, flow, temperature, and chemistry of the overlying water
What are the two types of freshwater ecosystems?
flowing-water and standing-water
How do marine biologists divide the ocean?
photic and aphotic; depth and distance from shore
What are the 3 zones that an ocean is divided into?
intertidal, coastal and open
What is plankton?
a general term for the tiny-free floating organisms that live in both freshwater and saltwater environments
What is phytoplankton? What do they do?
unicellular algae that use nutrients in the water and are the base of many aquatic food webs
What is a wetland?
an ecosystem in which water either covers the soil or is present at or near the surface of the soil for at least part of the year
What are the 3 main types of freshwater wetlands?
bogs, marshes, and swamps
What are estuaries?
wetlands formed where rivers meet the sea
What is detritus?
tiny pieces of organic material that provide food for organisms at the base of the estuary’s food web
What are salt marshes?
temperate-zone estuaries dominated by salt-tolerant grasses above the low-tide line, and by seagrasses under water
What are mangrove swamps?
coastal wetlands that are widespread across tropical regions; dominated by salt-tolerant trees collectively called mangroves
What is the photic zone?
the upper layer of the ocean where photosynthesis occurs; about 200 meters and producers live here
What is the aphotic zone?
below photic zone and is permanently dark; chemosynthetic autotrophs are only producers in this zone
What is the benthic zone?
covers the ocean floor
What is zonation?
the prominent horizontal banding of organisms that live in a particular habitat
What is the coastal ocean?
extends from the low-tide mark to the outer edge of the continental shelf; relatively shallow border that surrounds the continents
What are kelp forests?
most productive coastal ocean communities; giant brown alga can grow 50 cm a day
What are benthos?
organisms that live attached to or near the bottom of the ocean floor
