Ch 56 Flashcards
biome
a large, relatively distinct terrestrial region with the following characteristics: climate, soil, plants, animals, and interacting landscapes
tundra
a frozen layer of subsoil (permafrost) and low-growing vegetation that is adapted to extreme cold and a short growing season characterize tundra; the northernmost biome
taiga
coniferous trees adapted to cold winters; a short growing season; and acidic, mineral-poor soil dominate the boreal forest, or taiga
temperate rain forest
large conifers dominate temperate rain forest, which receives high precipitation
temperate deciduous forest
occurs where precipitation is relatively high and soils are rich in organic matter; broad-leaf trees that lose their leaves seasonally dominate temperate deciduous forest
temperate grasslands
typically has a deep, mineral-rich soil and has moderate but uncertain precipitation
chaparral
thickets of small-leaf evergreen shrubs and trees and a climate of wet, mild winters and dry summers characterize chaparral
desert
found in both temperate (cold deserts) and subtropical or tropical regions (warm deserts) with low levels of precipitation, contains organisms with specialized water-conserving adaptations
savanna
tropical grassland, called savanna, has widely scattered trees interspersed with grassy areas, savanna occurs in tropical areas with low or seasonal rainfall
tropical rainforest
mineral-poor soil and high rainfall that is evenly distributed throughout the year characterize tropical rainforest, tropical rainforest has high species richness and high productivity
human effect on biomes
in the tundra oil exploration and military exercises result in long-lasting damage; in the taiga and temperate rain forests clear cut logging is destructive; in the temperate and deciduous forests and tropical rain forests the trees and plants are being removed by logging and development
What are the two most important factors to determine biomes/climates?
precipitation and temperature; elevation has an effect, too
What are the 6 major biogeographic realms?
palearctic, Nearctic, Ethiopian, oriental, Australian, and neotropical; these realms are divided by either a large body of water, large desert, or large mountains
important environmental factors in aquatic ecosystems
salinity (saltiness), amount of dissolved oxygen (need 5ppm to support animal life), availability of light for photosynthesis (how deep and cloudy is the water), and depth
secondary abiotic factors involved with aquatic ecosystems
temperature, climate, and speed of flow
plankton
free-floating organisms
nekton
strongly swimming organisms, ex: fish, dolphins, sharks, etc
benthos
bottom-dwelling organisms
marine biomes salinity
marine biomes have a salt concentration of approximately 3% and cover approximately 75% of the earth’s surface
freshwater biomes salinity
freshwater biomes are usually characterized by salt concentration of less that 1% and are closely linked to the soils and biotic components of the terrestrial biomes through which they pass
photic zone
the zone through which light penetrates and photosynthesis can occur; the top layer
aphotic zone
the zone where very little light can penetrate; bottom layer
thermocline
a narrow stratum of rapid temperature change called a thermocline separates a more uniformly warm upper layer from more uniformly cold deeper waters
benthic zone
the benthic zone is the bottom of any aquatic biome and contains detritus or dead organic matter
flowing-water ecosystems
streams and rivers
standing-water ecosystems
ponds and lakes
freshwater wetlands
marshes and swamps
estuaries
coastal body of water with access to both the ocean and fresh water from rivers; the salinity of these areas can vary greatly but they are crucial feeding areas for many types of water fowl
head water streams
fast, clear, cold, and highly oxygenated; contains organisms adapted for the current; detritus is the major energy source
downstream rivers
slow moving, more sediment; warmer, less oxygen; organisms similar to those in lakes; more producers
littoral zone
the littoral zone is shallow and close to the shore; the shore zone with a lot of leaf litter
limnetic zone
the limnetic zone is the open surface water
profundal zone
the profundal zone consists of the deep, aphotic regions; not all lakes/ponds have a profundal zone
oligotrophic lakes
oligotrophic lakes are deep, nutrient-poor, and do not contain much life; ice melt lake found high up in the mountains; oligotrophic=no feeding
eutrophic lakes
eutrophic lakes are shallower and have increased nutrients; lots of feeding/plants; eutrophic=true feeding
mesotrophic lakes
have a moderate amount of nutrients and phytoplankton productivity
During what two seasons does the water in a lake/pond mix?
autumn and spring; in the summer and winter there is a distinct thermocline
freshwater wetlands
areas covered with water that support many types of plants; they can be saturated and include areas known as marshes, bogs, and swamps; they are home to many different types of organisms, from herbivores to crustaceans and are important as habitat refuges; help control flooding as well as recharge and cleanse ground water; wetlands are like sponges that can absorb flood water which is why it’s so bad for humans to drain them and build houses
intertidal zone
shoreline between low and high tides; sometimes under water, sometimes not but when it is under water it’s salt water
benthic environment
the ocean floor
neritic province
open ocean from shoreline to depth of 200 m
oceanic province
ocean deeper than 200 m
abyssal zone
deepest part of the benthic zone
pelagic zone
the open water
neritic zone
includes the shallow regions over the continental shelves
oceanic zone
extends past the continental shelves and can be very deep
ecotone
transition zone where two communities meet and intergrade; provides habitat diversity; is often inhabited by a greater variety and density of organisms than either adjacent community
What zone do coral reefs exist in?
the neritic zone; coral reefs are the marine equivalent of a tropical rain forest and are being affected by ocean acidification
