The web of life 8/31/2013 6:23:00 AM
Concept 1.1: events in the natural woalrd are interconnected
Connections in nature
Connections to nature: events in natural wolrd are connect:
connections when organisms interact with one another in
Early observations suggest that parasites cause amphibian deformaties.
Amphibian: ambystoma macrodactylum. Parasite: ribeiroia ondatrae.
Laboratory experiment tests the role of parasites. Control group- h.
regilla eggs not known to have frog deformation . given treatment:
increase number of parasite.
A field experiment suggest that multiple factors influence frog
deformities. Pesticide. Increase pesticide=increase infection
Connections in nature can lead to anticipated side effect; increase
fertilizeralgae growthsnail eat alge, snail growth.
Concept 1.2: ecology is the scientific study of interactions between
organisms and their environment
Ecology: study of interaction between organisms and environment./ study of
interactions that determine distribution-geographic location and abundance
Environment science: field that incorporates natural science (ecology)/ social
Public and professional ideas about ecology often differ. Public think
that there is a balance of nature-natural stystem are stable and
return to original after disturbance / each species have role of
maintaining balance. But! They do not return to original condition.
o 8 ecollogical maxims
you can never do just one thing-things are connect
everything goes somewhere-waste don’t go away
no population can increase size forever-limits
there is no free lunch-reproduction trade or growth?
Time matter-ecosystem change over time
Space matter-abiotic/biotic change. Local to global Life would be impossible without species interaction-
species depend on each other for reosource.
The scale of an ecological study affects what can be learned from it.
Scale-collecting observation including time/space.
Ecology is broad in scope. Population: group of one species in area.
Community: group of population in area . Biotic=living things.
Abiotic-non living things. Ecosystem: community of organism and
environment. Landscape: one place to another with many
ecosystem. Biosphere: all living organism and environment.
Some key terms are helpful for styding connections in nature.
o Adaptation: feature of an organism that improves it ability to
survive/reproduce in environment
o Natural selection: evolutionary process in which individual
that possess characteristic to surviv/e reproduce at higher
rates than others. E.g antibiotic.s
o Consumer: organism that obtain energy by eating others
o Producer: organism that use energy from external source=
sun= to produce food
o Net primary production: energy that producers fix by
photosynthesis minus cellular respiration = photosynthesis-
o Nutrient cycle: movement of nutrient between organism and
Change in genetic characteristic of population
Descent with modification: process where organism
accumulate differences with ancesteors.
Concept 1.3 Ecologists evaluate competing hypotheses about natural system
with observation, experiment and models
Anwering ecological questions
Ecologists use experiment, observation, model to answer ecological
questions. Climate change; directional change in climate that occurs
over 3 decade or longer. Experiments that are designed and analyzed in consistent ways.
Replicate=perform more than once / random treatment/ analyze
result. Plots. Statistical analysis=t test.
What we know about ecology is always changing. Scientific method:
o Observe nature and ask question about these observations
o Use previous knowledge to create hypothesis
o Evaluate hypothesis by xperiment
Deformity and decline in amphibian population.
Habitat loss, parasite, disease, pollution, overexploitation, climate
change, introduce species, UV light may contribute to amphibian
reducing. unit 1: organisms and their environment
Chapter 2: the physical environment. 8/31/2013 6:23:00 AM
Concept 2.1 Climate is the most fundamental component of physical
Anadromous; born in freshwateroceanreturn to freshwater:
Chemical environment: salinity-concentration of dissolved salt/
acidity-pH / concentration of gase/ dissolved water.
Climate: long term weatherat location, based on average/ variation
measured over decade
Weather: temperature, humidity, precipitation, wind, cloud cover.
Climate variation: change over year/intensity distribution of solar
ratdiation/concentration of co2 emit.
Climate conctorls where and how organism live. Temperature
determine rate of biochemical reaction/physiological activity.
Distribution of organism often reflect extreme
condition=temperature/moisture extreme affect forest
tree=drought. Variability: not just average conditions.
o Abiotic. Periodic disturbance=fire/avalanche
Global energy balane drives the climate change. Aerosol: solar
radiation reflected by clouds of aerosol. 1/3 from aerosol. 1/5
radiation absorbed by ozone,cloud, water vapoour.
o If temperature is the same, solar radiation observe by
infrared radiation=longwave radiation.
o Latent heat flux: heat loss due to evaporation. Conduction:
kinetic energy transfer direct contact. Convection: kinetic
energy transfer by wind/air/water. Sensible heat flux:
convection and conduction=above earths’ surface from warm
to cool air.
o Greenhouse gase: radiatively active gas: absorb and reradiate
infrared radiation= h2-/co2/ch4/n20.. without greenhouse
gas, temperature would be colder. Concept 2.2. winds and ocean currents result from differences in solar
radiation across earth’s surface
Atmospheric and oceanic circulation.
Earths’ movement cause:more radiationin equator and cause
seasonal climate variation.
Atmospheric circulation cells are established in regular latitudinal
patterns. Atmospheric pressure: force exerted on packet of
air/earth’s surface by air molecule above so it decrease with
increase altitude. As warm air rise higher, it expands, cools rising
o Condensation of water into clouds is warming process/
another form of latent heat transfer.
o Troposphere: atmospheric layer above earth surface. Above
o Stratosphere: next atmospheric layer above troposphere.
o Topics receive most precipitation because most solar
radiationmore heatinguplift of air/cloud formation. When
air between stratosphere and troposphere, it moves to poles
and meet cooler airsubsidence: descend toward earth’s
surface when moving air meets surrounding air at same
temperature high atmospheric pressure that inhibit
formation of cloud=desert.
o Hadley cell: tropical uplift of air creates atmospheric
circulation in each hemisphere. Polar cell: north/south poles
where dense cool air moves toward equator. Subsidence
occurs at poles=polar desert
o Ferrel cell: mid latitude between Hadley and polar cell.j polar
front: ferell cell move Hadley and polar cell by exchange
energy between tropical/polar air mass.
3 atmosphereic circulation cells:
o tropical: 30N and S
o temperate zone: 30 and 60 N and S
o Polar zones: above 60 N S
Atmospheric circulation cells create surface wind patter. Prevailing
winds: high to low pressure wind in atmospheric circulation cells
toward air movement patterns. Coriolis effect: pattern of wind appears curved because observer is moving with earth’s surface
due to earth’s rotation. This is apparent deflection. Outer space
fixed position is no apparent deflection.
o Trade wind: surface wind on 30N S appear west. Westerlies:
east blowing towards pole.
o Heat capacity: water can absorb and store more energy
without temperature changing than land can. Seasonal
changes in land more extreme than water. High pressure cells
form over oceans=around 30 n s. northern hemisphere have
more semipermanent pressure cells than southern because
north have more land mass. Wind blows from high to low
Ocean currents are driven by surface winds.
o Wind blows ocean surface frictional drag move surface
water coriolis effect where water seems to move at an
angle. Right in north hemisphere. Left in south. This is why
ocean current similar to prevailing wind.
o Ocean water do not mix because of different temperature /
salinity. Dense downwalling current moves cold polar to warm
tropical ocean. Upwelling: ocean water rises to surface:
prevailing wind blow parallel to coastline. Upwelling also
brings nutrients back into the ocean. When surface water
organism die, they go to bottom and upwelling brings it up to
form photic zone and phytoplankton eats it then zooplankton
o Ocean currents responsible for 40% heat exchange between
trpic/polar. Wind responsible for 60%. Heat pumps/thermal
conveyer=ocean current=pacific, indian, atlantic ocean.
Concept 2.3: large-scale atmospheric and oceanic circulation patterns
establish glal batterns of temperature and precipitation
Global climatic patterns
Oceanic circulation and distribution and topography of continents
influence global temperatures. Annual temperature variation is where air temperature over land show seasonal variation in warm
temperature than cold temperature.
Why is it colder in mountains than lowlands?
o Atmospheric pressure=density of air decrease, elevation
increase sea level. Few air molecules absorb infrared energy
radiating from earth’s surface. So even if high land have more
solar radiation, heating of ground is less effective because low
o High land exchange air more effectively with cool air in
surrounding atmosphere because atmosphere is warmed by
infrared radiation. Temperature decrease with increase
distance from ground. Lapse rate: decrease temperature
increase height. Increase wind velocity increase elevation
because less friction, decrease air temperature increase
elevation lapse rate
Patterns of atmospheric pressure and topography influence
precipitation. Pressure cells influence movement of moist air from
oceans to continent/could formation. E.g high pressure in south
pacific ocean decrease precipitation in west coast. Mountains
influence precipitation by forcing air moving across them to rise
Concept 2.4 regional climates reflect influence of distribution of
Regional climatic influences
In different climate change: air temperature increase, humidity
decrease, precipitation decrease.
Proximity to oceans influences regional climates. Maritime climate:
coastal terrestrial regionas influenced by ocean. Little variation in
daily/seasonal temperature/high humidity. Continental climate:
greater variation in daily and seasonal temperature.
o Maritime climate occur in all climatic zones from tropical to
o Temperatre zone influence oceans in coastal climates on est
coast in northern hemisphere & east coast in sourther
hemisphere because of prevailing wind. mid+high latitude=temperatue zone where large seasonal change
because solar radiation and low heat capacity of land mass.
Mountains influence wind patterns and gradients in temperature
and precipitation. What cause vegetation change? From grassland
to forest? Climate of mountain produce effect on
topography/elevation on air temperature/behavior of air mass/ own
local wind pattern.
o Rainshadow effect: in leeward slope L: lower precipitation and
soil moisture on flope facing away from prevailing wind.
Windward: higher precipitation/moisture on slope facing on
It affects: types/amount of vegetation on mountain
range. Windward: luch productive plant.
o Mountains can generate own local wind/precipitation pattern.
Slope exposure or slope aspect. In Hadley cells, differences in
solar heating cause air to become warming.--> more solar
radiation when sun rise in eastupslope wind. At night:
cold air drainage: at high elevation: cold air flow downslope
that cause valley bottom to be cold: it influence vegetation
distribution in temperate zone because higher subfreezing
temperature in low areas.
o Cordilleras: large mountain chains channel movement of air
masses. At continental: mountain influence movement,
position, ehaviour of air and temperature of lowland.
Vegetation affects climate through surface energy exchange.
o Albedo: capacity of a land surface to reflect solar radiation is
influenced by presence/type of vegetation/soil/topography.
Light color surface=high albedo. Coniferous forest is dark
color=low albedo and soil absorbs more energy.
Evapotranspiration: sum of water loss through transpiration
and evaporation increases with area of leaves of ground
surface area. Evapotranspiration transfer energy (latent heat)
and water into atmosphere by affecting air
temperature/moisture. Loss of tree increase albedo as bare
soil is exposed. High albedo decrease absorption of solar
radiation=less heating on land surface.=low evapotranspirative cooling 9lower latent heat transfer)
because of loss of leaf area=reduce surface cooling=lower
precipitation = less moisture.
2.5 seasonal and long term climatic variation are associated with changes in
earth’s position relative to the sun
Climatic variation over time.
Seasonality results from annual orbit of earth around the sun.
closet to sun on jan, farthest on july. Seasonality in tropics-change
in precipitation rather than temperature because solar radiation
change is small in temperate/polar zone.
o ITCZ intertropical convergence zone=zone of maximum solar
radiation between n/s hemisphere. Zoen of maxmum solar
radiation =zone of max warm air uplift and precipitation. E.g
in northern hemisphere: N to S brings wet in jul to oct. In
south; N to S have wet in oc to feb
o Seasonal change in temperate and polar zone: affect
temperature/solar radiation/length of the day
Seasonal changes in aquatic environment as associated with
changes in water temperature and density.
o Stratification: layer of water in ocean/lake with water
temperature differences. (mixing occurs in upwelling0. In
temperate lakes: epilimnion: n summer where warmest is
surface water. Below epilimion is thermocline. Below
thermocline is hypolimnion/benthic zone. During fall: air
transferincrease densityall water
depths:epilmnion/epiliminion/hypolimnion will have same
temperature and densityturnover: mixing of epimnion and
hypolimnion recycle nutrient/move oxygen. Turnover occurs
in spring and fall too when ice melts.
Climatic variation over years and decades results from changes in
atmospheric pressure cells.
o El nino southern oscillation: south America: high pressure to
low cells over pacific and weaken east winds that normally
push warm water to southeast asia. Less upwelling. La nina: stronger phases with high pressure in south America, low
pressure in west pacific. Le nino then la nina happens.
La nina brings dry condition in indonasia
droughtsfire. La nina brings precipitation to mexico.
o North atlantic oscillation: affects climate variation in Europe,
north asia, east NA.
o Pacific decadal oscillation ; pdo; pdo similar to enso.;
northwest na central America/asia/austrailia
Long term climate change is associated with variation in earth’s
orbital path. Continental drift: movement of land mass across
earth. High greenhouse effect=increase warmer period. But
radiation is increasing does not show affect on long term global
o Glacial maxima: peak of glacial interglacial period : called
o in earth elliptical orbit=greater distance from sun=less solar
radiation. Earth angle has hange which cause more seasonal
variation.now angle is 23.5
concept 2.6 salinity, acidity and oxygen concentrations are major
determinants of the chemical environment
the chemical environment. Chemical influence biological function:
all waters contain dissolved salts
salinity: concentration of dissolved salt in water. Near equator: high
salinity. Ocean salt: nacl, mg, ca, sulfate, bicarbonate, K. salt came
from volcanic euroption cooling of minerals that soon break off.
o High salinity that occur naturally is water soil near ocean. E.g
salt marshes. Soil can become more saline by: plant
roots/irrigation pump deep soil to surface soil. Salinization:
when less precipitation and built up salt in soil: desert soils.
Cause of Mesopotamia agriculture decline.
Organisms are sensitive to acidity of their environment.
o Acidity/alkalinity: measure of ability of solution to behave as
acid/ base. In ocean, pH does not vary becaue salt act as
buffer. There is pH difference in land and surface water because: water become more acidic as more acidic compound
added such as soil development.
2 parts of soil: mineral particles from breakdown
rock/organic matter such as dead plant. Some raocks
such as granite have acidic salt/while others basic salt.
Soil become more acidic becase basic salt leach
Oxygen concentrations vary with elevation, diffusion, consumption
o Hypoxic: archaea/bacteria/fungi can live in these low oxygen.
Low oxygen in deep sea because slow rate of diffusin. Oxygen
concentration highest in freshwater/moving
water/stream,rivers because mixing of atmosphere occurs.
Climatic variation and salmon abundance; pdo. Pdo shorter than
Climatic variation and ecology: pdo exist to understand animal
population. We don’t know what cause pdo. The Biosphere 8/31/2013 6:23:00 AM
The American Serengeti-12 centuries of change in the great plains: case
study. Central NA=great plains because it looks like Africa. Large animals
became extinct in NA. megafauna. Reason: climate change limit food supply
/ humans./fire/grazing/precipitation/intensity of water.
Biosphere: zone of life on earth between lithosphere(earth surface crust and
upper mantle ) and troposphere (lowest layer of atmosphere). Biomes:
diversity of terrestrial life on earth.
Concept 3.1 terrestrial biomes are characteriszed by growth forms of
Biomes do not categorize taxomic relationship but similarities in
morphological response to environment. Similar biotic
assemblage=similar response to climate force in locations.
Terrestrial biomes are classified by:
o growth form (size/morphology) of plants (trees),
o leaves (deciduous-shedding)
o succulence –development of fleshy water storage tissue.
We use plants because it is immobile nad occupy site for a longer
time and cope with environmental extreme and pressure –
competition for water/nutrient/light- aridity, high and subfreezing
temperature, solar radiation , nutrient poor soil, grazing animal,
o To cope: use convergence: evolution of similar growth forms
among distantly related species to respond pressure. E.g
woody tissue/grow from their leaves.
We don’t’ use microorganisms-archaea, bacteria, fungi, because
they are too rapid to changes and tiny size.
Terrestrial biomes reflect global patterns of preceipitation and
o Climatic variation and terrestrial biome predict biome
distribution through precipitation and tmerpaterature
Other factures affecting biome distribution: soil texture,
chemistry, mountains, bodies of water. The potential distributions of terrestrial biomes differ from thei
actual distribution due to human activies.
o Land use change: human effects where land resource
extracted. Agriculture/logging/livestock grazing.
o Climate diagram: characteristic of seasonal patterns of air
temperature and precipitation at location of that biome.
Yellow=water shortage. Blue=subfreezing
Tropical rainforest. Low latitude. ITCZ has high precipitation. Seasonal
climatic rhythms absent, and plants grow continuously. Most productive
Africa, central/S America, austrailia, southeast asia.
Highest to lowest plants: emergent treescanopy (evergreen)
lianas; woody vines and epiphytes: tree branches
understoryforbs: broad leave herbaceous plants on forest floor
rely on little light.
Tropical seasonal forest and savannas
Rainfall become more seasonal. Shorter vegetation, more drought.
Plants: complex vegetation: tropical dry forest, thorn woodland:
tree and strub, tropical savannas: grasses mixed with trees and
Was once greater than rainforest, now lower.
Asia, central S America.
Descending Hadley cells.
Convergence in plants: stem succulent store water for dry periods.
Another convergence: active only in precipitation.
Irrigation in desert fail because of salinization. Desertification: long
term drought with unsustainable grazing resulting loss of plants and
Greater seasonal temperature variation with increasing subfreezing
temperature. Enough precipitation to support forest/ grassland
mainly for agriculture/pastoral development because the grass
needs to grow deeper root to reach water=more fertility.
Salinization because of irrigation and desertification occurs. Temperate shrublands and woodlands.
Woodlands: open canopy of short tree. Shrubland: winter rainy
season. Mediterranean type climate: west America, Africa, Europe,
Precipitation and summer growing season=the time only when