Chapter 52: An Introduction to Ecology and the Biosphere Flashcards
ecology
scientific study of the interactions between organisms and the environment
global ecology
examines influence of exchange of energy/materials on organisms across the biosphere
biosphere
all ecosystems and landscapes of the planet
landscape ecology
factors controlling exchange of energy, material, and organisms across multiple ecosystems
landscape
multiple connected ecosystems
ecosystem ecology
energy flow and chemical cycling between organisms and environment
ecosystem
community of organisms in an area and physical factors with which they interact
community ecology
how community structure and organization are affected by interactions between species
community
group of populations of different species in an area
population ecology
analyzes factors affecting population size over time
population
group of individuals of same species in an area
organismal ecology
how organism’s structure, physiology, and behavior meet environmental challenges
organismal ecology includes
physiological, evolutionary, and behavioral ecology
climate
long-term weather conditions in a given area
climate is most significant influence on
distribution of organisms
components of climate
temperature, precipitation, sunlight, wind
macroclimate
climate patterns on global, regional, and landscape scale
microclimate
fine, localized climate patterns
global climate patterns determined by
input of solar energy and Earth’s movement in space
tropics
regions between 23.5 degrees north and south
high temperatures and evaporation in tropics cause
lots of precipitation
air flows towards from tropics towards poles so 30 degrees north and south have
dry, arid climate
air picks up moisture across the land
around 60 degrees north and south
water content is dumped
from 60 degrees north and south, air continues to flow towards poles causing
cold and rainless climate
which wind patterns are favored due to the rotation of the Earth?
easterly and westerly
easterly winds
cool winds blowing east to west in tropics
westerly winds
blow west to east in temperate zones
seasonality
Earth’s rotation and tilted axis cause strong seasonal cycles in middle/high altitudes
in june earth is tilted
towards sun
in december earth is tilted
away from sun
Earth has constant tilt of
23.5 degrees
September and March equinoxes
no tilt towards/away from sun - exactly 12 hours of daylight and 12 hours of darkness
bodies of water impact climate by
heating/cooling of air masses by ocean currents
impact on climate by water during the day
land hotter than water, cool wind from water across land
impact on climate by water during the night
water hotter than land, cool wind from land to water
mediterranean climate
hot, arid climate inland due to cool ocean breeze absorbing moisture
around Mediterranean Sea, southern CA, southwestern Australia
mountains impact climate cause
warm, moist air approaches mountain, rises, and dumps water content creating a rain shadow
impact of rain shadow on leeward side of mountain
dry, desert conditions as air picks up moisture
every 1000m increase in elevation causes a
6 degrees Celsius drop in temperature
regional and local climate impacted by
seasonality, bodies of water, mountains
microclimate influence by
shade, evaporation from soil, wind patterns
abiotic factors
nonliving (chemical and physical) factors
biotic factors
living factors
abiotic and biotic factors factors make up
environment
global climate change
large-scale change in climate affects biosphere and thus distribution of organisms
last seen example of global climate change
end of most recent Ice Age
biomes
major life zones characterized by vegetation type (terrestrial) and physical environment (aquatic)
climograph
plot of annual mean temperature and precipitation in a region
biomes characterized by
major physical/climate features, predominant vegetation, microorganisms, fungi, animals
ecotone
area of intergradation between different biomes
vertical layering
upper canopy, low-tree layer, shrub understory, ground layer, forest floor (litter layer), and root layer
vertical layering allows for
variation of habitat
disturbance
event that changes a community removing organisms from it and altering resource availability
disturbance causes biomes to exhibit
several different communities
tropical forest
equatorial and subequatorial regions
much precipitation, high temperatures
tropical forests have highest
animal diversity of all biomes
how have humans impacted tropical forests
deforestation
desert
30 degrees north or south; interior areas of land
little precipitation, great variation in temperature
how have humans impacted deserts
irrigated agriculture has reduced biodiversity
savanna
equatorial and subequatorial regions
some rainfall, hot weather but still exhibits seasons
how have humans impacted savannas
cattle ranching and overhunting
chaparral
midlatitude and coastal regions
rainy winters, dry summers; seasonal temperature range
how have humans impacted chaparrals
agriculture, urbanization, fires
locations of temperate grasslands
veldts of South Africa, puszta of Hungary, pampas of Argentina and Uruguay, steppes of Russia, and central North America
conditions of temperate grasslands
dry winters, wet summers
some rainfall, occasional drought
seasonal temperature range
how have humans impacted temperate grasslands
agriculture and overgrazing - some turned to deserts
taiga
northern North America and Eurasia
medium precipitation, periodic drought; seasonal temperature range
taiga is largest
terrestrial biome
how have humans impacted taigas
logged at rate quicker than can be regrown
temperate broadleaf forests
midlatitude
decent amount of precipitation; seasonal temperature range
how have humans impacted temperate broadleaf forests
heavily settled by humans, used for agriculture
tundra
20% of earth’s land in the Arctic
some precipitation, cold temperatures
alpine tundra
very high altitude, high wind, low temperature, high precipitation
how have humans impacted tundras
used for mineral and oil extraction
aquatic biomes characterized by
physical environment
marine biome salt concentration
3%
freshwater biome salt concentration
0.1%
freshwater biomes effected by
soil and biotic components of surrounding terrestrial biomes
photic zone
where light is sufficient enough for photosynthesis
aphotic zone
where little light penetrates
photic and aphotic zones make up
pelagic zone
abyssal zone
ocean that is 2000-6000m belos surface
benthic zone
bottom of all aquatic biomes made up of sands, sediments
benthos
communities of organisms that inhabit the benthic zone
detritus
dead organic matter that is food for many benthic species
thermocline
layer of abrupt temperature change due to sunlight penetration
turnover
oxygenated water from surface of lake moves to bottom in the spring and autumn, sending nutrient water to the surface
littoral zone (lakes)
closer to land
limnetic zone (lakes)
farther from land
intertidal, neritic, and oceanic zones
distance from shore and water depth
stratification in lakes
light decreases with depth
temperate lakes have _____ thermocline
seasonal
tropical lakes have _____ thermocline
all year round
oligotrophic lakes
nutrient poor, oxygen rich
eutrophic lakes
nutrient rich, oxygen poor in summer and winter
oligotrophic lake may become eutrophic due to
runoff adding nutrients and sediments
runoff from fertilized land causes nutrient enrichment which can lead too
algal blooms, oxygen depletion, fish death
wetlands
habitat flooded some of the time
how have humans impacted wetlands
draining and filling has destroyed 90% of wetlands
temperature of streams vs. rivers
streams tend to be colder, rivers tend to be warmer
how do salt and nutrient content vary in rivers
increase from headwaters to mouth
how have humans impacted rivers
pollution, damming and flood control
estuary
transition between river and sea, salinity varies with tides
how have humans impacted estuaries
filling, dredging, pollution
intertidal zones
areas periodically submerged and exposed by tides (twice daily on marine shores)
how have humans impacted estuaries
oil pollution and construction of jetties
ocean pelagic zone
open water constantly mixed by wind and currents
high oxygen levels, low nutrient levels
how have humans impacted ocean pelagic zone
overfishing and pollution
coral reefs formed from
calcium carbonate skeleton of corals
high oxygen levels, high inputs of freshwater and nutrients
progression of coral reefs
fringing reef to barrier reef to coral atoll
how have humans impacted coral reefs
collecting of coral skeletons, overfishing, pollution
marine benthic zone
seafloor below surface waters
receives no sunlight, low temperature, high pressure
deep-sea hydrothermal vents support life of
chemoautotrophic prokaryotes
how have humans impacted marine benthic zone
overfishing and dumping
ecological time
minute-to-minute time frame of interactions between organisms and environment
evolutionary time
time frame of many generations
dispersal
movement of individuals or gametes away from origin or centers of high population density
long distance dispersal can lead to
adaptive radiation (rapid evolution)
transplants
relocation of species to see if organism survives and reproduces
why do ecologists observe transplants
to determine if dispersal limits distribution
distribution may be limited by
habitat selection behavior
predators may limit distribution of
prey (which may limit distribution of plants)
examples of biotic limitations
pollinators, food resources, parasites, pathogens, competing organisms
abiotic limitations
temperature, water availability, oxygen content, sunlight, salt concentration (aquatic biomes)
abiotic limitations of plants (indirectly impacts animals)
pH, mieral composition, structure of rocks/soil
