Chapter 52 Flashcards
What is ecology?
the scientific study of the interactions between organisms and the environment
What does ecology include?
all organisms, in how they relate to each other and the environment
What do ecological interactions determine?
distribution of organisms and their abundance
What does modern ecology include?
observation and experimentation
What two questions are asked in ecology?
What environmental factors limit geographic distribution?
What factors (food, pathogens) affect population size?
How does ecology work?
at levels ranging from individual organisms to the planet
What are the 6 levels of ecology?
Organismal > Population > community > Ecosystem > landscape > global
What is a biosphere?
global ecosystem, the sum of all the planet’s ecosystems
What does global ecology examine?
the influence of energy and materials on organisms across the biosphere
What is a landscape/seascape?
mosaic of connected ecosystems
what does landscape ecology focus on?
exchanges of energy, materials, and organisms across multiple ecosystems
What is an ecosystem?
community of organisms in an area and the physical factors with which they interact
what does ecosystem ecology emphasize?
energy flow and chemical cycling among the various biotic and abiotic components
what is a community?
a group of populations of different species in an area
What does community ecology examine?
the effect of interspecific interactions on community structure and organization
what is a population?
a group of individuals of the same species living in an area
What does population ecology focus on?
factors affecting population size over time
What is organismal ecology?
studies how an organism’s structure, physiology, and behavior meet environmental challenges
what does organismal ecology include?
Includes physiological, evolutionary, and behavioral ecology
what is a climate?
long-term prevailing weather conditions in an area
what are four major abiotic components of climate?
temperature, precipitation, sunlight, and wind
What is macroclimate?
patterns on the global, regional, and landscape level
What is microclimate?
very fine patterns, such as those encountered by the community of organisms underneath a fallen log
what are global cimate patterns determined by?
the sun and Earth’s movement in space
What does the sun cause?
temperature variation, driving evaporation and circulation of air and water
What does circulation of air and water lead to?
latitudinal variations in climate
How does the angle of the sun affect the earth?
ntensity of the amount of heat and light per unit of surface area
Where is the tropics?
23.5 north latitude and 23.5 south latitude
Where is sunlight most intense, and why?
strongest in the tropics where sunlight strikes Earth most directly
Why are the poles cold year round?
low angle of incoming sunlight
What plays a major role in determining climate patterns?
Global air circulation and precipitation patterns
How does water evaporate and move in the tropics?
warm, wet air masses flow from the tropics toward the poles
How does dry air contribute to climate? (2)
Descending dry air towards the equator absorbs moisture
Creates arid climates, near 30 degrees north and south
What does moist air do in the climate?
Ascending moist air towards the poles releases moisture
What causes high precipitation?
rising air massses
What does air flowing close to the surface allow?
predicting global wind patterns
How do trade winds travel?
blow from east to west in the tropics
How does westerlies travel?
from west to east in the temperate zones
What three things affect climate?
Seasonality
Large bodies of water
Mountains
What increases towards the poles?
Seasonal variations of light and temperature
what causes seasonality at high latitudes?
tilt of earth’s axis of rotation and its annual passage around the sun
What shifts as the angle of the sun changes?
Belts of wet and dry air straddling the equator
What does changing wind patterns affect?
ocean currents
What do oceans and its currents moderate?
climate of nearby terrestrial environments
Where do currents take cold water?
from poles to the equator
Where do currents take warm water?
from equator to the poles
What do large gyres do?
impact climate of terrestrial regions
How do breezes move during the day?
air rises over warm land and draws a cool breeze from the water across the land
How do breezes move during the night?
As the land cools at night, air rises over warmer water and draws cooler air from land back over the water, which is replaced by warm air from offshore
How does rising air affect mountains?
releases moisture on the windward side of a peak and creates a rain shadow as it absorbs moisture on the leeward side
How do mountains and sunlight interact?
Mountains affect the amount of sunlight reaching an area
How does the south and north differ in sunlight and mountains?
in the northern hemisphere, south-facing slopes receive more sunlight than north-facing slopes
How does elevation and temperature correlate?
Every 1,000 m increase in elevation produces a temperature drop of approximately 6 degrees Celsius
What is microclimate determined by?
fine-scale differences in the environment that affect light and wind patterns
What abiotic factors characterizes the environment?
nonliving attributes such as temperature, light, water, and nutrients
What biotic factors characterizes the environment?
other organisms that are part of an individual’s environment
How do you predict future climate change?
study previous change
How does glaciers correlate with terrestrial climate?
As glaciers retreated in the past, tree distribution patterns changed
How does climate change affect species?
species that have difficulty dispersing may have smaller ranges or could become extinct
What do fossil fuels and deforestation cause?
increasing CO2 concentrations in the atmosphere and other greenhouse gases
How much has the earth warmed since the 1900s?
.8 celsius
How much is it projected to warm by 2100?
1-6 degrees
How can we use the past ice age?
predict how global warming affects the distribution of living things
How did trees expand after the ice age? (2)
Tree seeds expand northwards after ice ages
Those with winged seeds are more rapidly expanded
How has climate chane affected distribution of organisms?
Trees, butterflies, and diatoms have shifted northwards
How has diatoms shifted environments?
due to receding arctic sea ice, making water flow possible
What are biomes?
major life zones characterized by vegetation type (terrestrial biomes) or physical environment (aquatic biomes)
What does climate determine regarding biomes (2)?
why terrestrial biomes are found in certain areas
location of terrestrial biomes
What is a climograph?
plots annual mean temperature and precipitation in a region
What are biomes affected by?
not just by average temperature and precipitation, but also by the pattern of temperature and precipitation throughout the year
What are terrestrial biomes named after?
major physical or climatic factors and for vegetation
What are ecotones?
area of intergradation, ranging from wide or narrow
What is an important feature of terrestrial biomes?
vertical layering
vertical layer example
Forest might consist of an upper canopy, low-tree layer, shrub understory, ground layer of herbaceous plants, forest floor, and root layer
What does layering provide?
diverse habitats for animals
How does species composition and biome interact?
same biomes in different areas can vary
How can different species in the same type of biome evolve?
Similar characteristics can arise in distant through convergent evolution
What is a disturbance?
event such as storm, fire, or human activity that changes a community
How can fire affect savamma biomes?
Frequent fires kill woody plants and maintain savanna vegetation
How can hurricanes affect forests?
Hurricanes create openings in forests to allow different species to grow
Why are disturbances important?
In many biomes, dominant plants depend on periodic disturbances
what are terrestrial biomes characterized by? (5)
distribution, precipitation, temperature, plants, and animals
Where is a tropical forest found?
equatorial and subequatorial region
What are three characteristics of a tropical forest?
Constant temperature
Vertically layered, with competition for light
Rich in animal species
How do tropical rain forests differ from dry forests?
Tropical rain forest- rainfall is constant
Tropical dry forest- precipitation is highly seasonal
Where are deserts found?
30 degrees north and south, and interior of continents
2 characteristics of deserts?
Temperature variable seasonally
Can be hot or cold
How do desert plants adapt?
for heat and desiccation through water storage and reduced leaf surface area
what kind of animals are found in deserts?
nocturnal or migratory
