Download Mutualism- A symbiotic relationship in which both species benefit

Mutualism- A symbiotic relationship in which both species benefit.
Parasitism- is a symbiotic relationship in which one species benefits at the expense of
the other
Lichen
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consists of a fungus and alga in a symbiotic relationship (Why did the algae and
the fungus get married? They took a lichen to each other.)
Fungus absorbs water
Alga does photosynthesis
2.2 Measuring Abiotic Components of the System
Measuring Abiotic Components
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Three types of ecosystem:
1. Marine (Sea, Estuaries – marine systems because they have high salt
concentration, Salt Marshes, Mangroves)
2. Freshwater (Rivers, Lakes, Wetlands) (Local examples: Howell Wetlands,
Ohio River)
3. Terrestrial (Land Based) (Local Examples: Wesselman Woods, Audubon
State Park)
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Abiotic Factors of a Marine System
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Abiotic Factors of Freshwater Systems
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Salinity
pH
Temperature
Dissolved Oxygen
Wave Action
Turbidity
Flow Velocity
pH
Temperature
Dissolved Oxygen
Abiotic Factors of Terrestrial Systems
1. Temperature
2. Light Intensity
3. Wind Speed
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Particle Size
Slope/Aspect
Soil Moisture
Drainage
Mineral Content
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Distribution of Earth’s Water
o 3% Fresh Water
 30.1% of Freshwater is Groundwater
 68.7% of Freshwater is in Ice and Glaciers
 .03% of Freshwater is Surface Water
 2% in Rivers
 11% in Swamps
 87% in Lakes
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Evaluating Measures for Describing Abiotic Factors
o Light
 A light-meter can be used. It should be held at a standard and fixed
height above the ground and read when the value is fixed. Values
must be taken several times a day and the same atmospheric
conditions.
 Cloud cover can change light intensity.
o Temperature
 Lab work: Mercury Thermometer (too fragile for Field Work)
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Fieldwork: Use an electronic thermometer with data probes.
Temperature can be measured in air, water, and soil. Temperature
should be taken at standard depth.
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Materials: pH meter or data logging probe
Values in Freshwater range from slightly basic to slightly acidic
Factors that affect pH: Surrounding soil, rock, and vegetation
Sea water usually has a value above 7.
Probe must be cleaned between each reading.
pH
Wind
Measurements can be taken based on wind’s effect on objects
The effects are related to the Beaufort Scale
Precise measurements can be made with a Digital anemomter.
Gusty conditions may lead to large variations in data
Particle Size
 Particle size of soil determines drainage and water-holding capacity
 Large particles can be measured individually
 Smaller particles can be measured by using a series of sieves with
increasingly fine mesh size.
 Smallest particles are separated by sedimentation,
Slope
 Slope determines surface runoff
 Can be calculated using a clinometer
Soil Moisture
 To find amount of water evaporated in soil: Weigh soil sample
before and after heating
 Temperatures must not be too hot or else organic content will be
burned off.
 Repeated readings need to be taken until no further weight loss is
recorded.
 Soil Moisture probes can be used, but can be inaccurate
Mineral Content
 Loss on Ignition (LOI) Test determines mineral content
 Soil Samples are heated (500 -1000 C) for several hours so volatile
substances can escape
 mass loss is equal to the amount of minerals present
 There are NO standard methods
 Same conditions should be used when comparing samples
Flow Velocity
 Surface Flow Velocity—Measure how long it takes a floating object
to travel a certain distance
 More Accurate Measurements – use a flow meter!
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The propeller is inserted into water and many readings are
taken.
 Water flow varies over time because of rainfall or glacial melting
events
o Salinity
 Use an electrical conductivity or use the density of the water (water
with high salt content is more dense)
 Salinity is expressed as parts of salt per thousand parts of water
 Sea Water – 35ppt
o Dissolved Oxygen
 Oxygen sensitive electrodes connected to a meter can be used
 care must be taken to avoid contamination
o Wave Action
 High wave action = high levels of dissolved oxygen (mixing of air
and water in turbulence)
 Measured using a dynamometer which measures force in waves
 must use an average value
o Turbidity
 Cloudy water = high turbidity
 clear water = low turbidity
 Turbidity effects the amount of light that can go into water, and
therefore rates of photosynthesis
 Measured using a Secchi Disk
 Problems: Sun’s Glare on water, Subjective nature of the
measure because a person’s eyesight might be better or
worse than another’s
 Solution: Take measure on Shady side of boat
 Mephelometer or turbidimeter can also be used
 measures light intensity scattered at 90 as a beam of light
passes through the water sample
Evaluation of Techniques
o Limitations: Short-term and limited field sampling (factors may change
from season to season or at different times of day)
o Dataloggers provide continuous data over long periods of time so the data
better represents the area.
o More samples = more reliable
2.3 Measuring Biotic Components of the System
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Keys for Species Identification
o Ecology—Study of Living Organisms in relation to their environment
o Important to identify organisms. if it is identified incorrectly, results will be
invalid
o Dichotomous keys—written so that the reader can identify an organism
using steps
o Each step is based on characteristic of a species
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Example
Describe and Evaluate Methods for Estimating Abundance of Organisms
o Impossible to study every organisms in an ecosystem
o Trapping methods allow for a sample to be taken
 Examples:
 Pitfall traps (Beakers or pots buried in soil, when animals fall
in the cannot escape!)
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Small mammal trap (baited with a door that falls once animal
is inside the trap)
Light Traps (a UV bulb against a white sheet that attracts
insects)
Tullgren Funnels(paired cloth funnels with a light source at
one end, a sample pot in the other and mesh in between)
percentage cover of organisms (organisms that are limited in
movement) or by calculating abundance using a formula
(Lincolns index)
o
The Lincoln Index
 Allows a researcher to estimate total size of population
 Involves collecting a sample from a population and marking them
(not in a way to make them more likely to be killed and eaten ex) fur
clipping) and releasing the animals.
 Then the area is sampled again and the number of marked
individuals are counted (capture-mark-release-recapture)
 Movement of animals in and out of study area can make results
inaccurate
 MULTIPLE TRIALS
 Equation: N=n1 x n2/m
 N—total population of animals in the area
 n1—number of animals first captured
 n2—number of animals recaptured
 m—number of marked animals recaptured
 Quadrats
 Used to limit sampling area when measuring population size
of non-mobile organisms
 vary in size
 If the same habitat is found throughout: quadrats should be
located at random (Random number generator).
 1. mark out area of habitat using two tape measures placed
at right angles
 2. use random number generator to locate positions within
the area
 If the sample has different habitats: Use Stratified random
Sampling
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Population Density is the number of individuals of each species for
unit area. Calculated by dividing number of organisms sampled by
total area covered.
 Percentage Frequency—the percentage of the total quadrat
number that the species was present in
Describe and Evaluate Methods for Estimating the Biomass of Trophic Levels
o Pyramids of biomass show biomass at each trophic level
o Biomass is calculated to indicate total energy within a living being or
trophic level
o Molecules are held together by energy so a larger mass indicated more
energy
o Biomass is taken by subtracting the mass from the water content
o Water is not included because it has no energy and is not organic
Diversity and Simpson’s Diversity Index
o Diversity – the number of different species and the relative numbers of
individuals of each species.
o Equation: D= N(N-1)/ Sum of n(n-1)
 D= diversity index
 N= total number of organisms of all species
 n= total number of individuals of a particular species
o Samples must be comprehensive
o Measures of diversity are relative, NOT absolute
o Comparisons can be made between similar communities, but not different
types
2.4 Biomes
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Biome – a collection of ecosystems sharing similar climatic conditions, has
distinctive Abiotic factors, water, insolation, and temperature are the most
important factors.
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Water is needed for:
o Photosynthesis, Transpiration and support (cell turgidity)
Sunlight is needed for:
o Photosynthesis
Temperature needed for:
o Photosynthesis (affects rate)
Photosynthesis determines productivity of ecosystem
Tri-cellular Model of Atmospheric Circulation
o Helps explain differences in pressure belts, temperature, and precipitation
o Thee major cells : Hadley, Ferrel, and Polar
o Hadley cell is over the tropics, warm air, unstable air
o Equator receives most sunlight
condenses
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Highest rainfall per unit area
Pressure is high and air cools
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Tropical Rainforest
o Constant high temperatures and high rainfall
o Exist around the equator
o High light levels
o Little seasonal variation
o All year growing season
o Broad evergreen forests with high diversity
o Many different niches available
o not much inorganic material needed for growth in the soil
o Rapid recycling of detritus provides trees with nutrients
o Heavy rainfall washes nutrients from soil which limits primary production
o Trees have shallow root systems and one long tap root as adaptation to
thin soil.
o Canopy protects soil from heavy rainfall
o after logging soil quickly erodes making it difficult for plants to grow
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Deserts
o Found in bands at latitudes of 30 N and S.
o Cover 20 -30% of the land surface
o Dry air descends having lost its water over the tropics
o Lack of water limits photosynthesis
o Fluctuation in temperature
o Low productivity but soil can be rich in nutrients
o Decomposition rates are low
o Adaptations to xeric (dry) conditions.
 Leaves or spines
 Waxy covering of leaves
 Deep Roots
 Extensive root systems near surface
 Cold blooded metabolisms Mammals live underground
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Tundra
o Found at high latitudes
o Adjacent to ice margins
o insolation is low
o Short day lengths
o Little Rainfall
o Photosynthesis and productivity low
Temperate Forest
o Found between 40 -60 N of the equator (seasonal areas)
o Two Tree Types
 Evergreen (protection against cold winter – Thicker leaves or
needles)
 Deciduous (Lose leaves in winter)
o Rainfall 500-1500 mm per year
o Variation in insolation caused by tilt of the earth
o Reasonably thick leaf layer on forest floor
o Nutrient availability is not limiting
Grassland
o Found on every continent (except Antarctica)
o Wide diversity but low productivity
o Rate of decomposition is not high because of cool climate
2.5 Function
The Role of Producers, Consumers, and Decomposers
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Producers—convert sunlight into food
Heterotroph—eat other organisms
Decomposers—decompose other organisms (recycles elements)
Producers
o Ex) plants algae and some bacteria
o Green plants are photoautotrophs(use sun)
o Basis of ecosystems
o Input energy and new biomass
QUIZ
1. Match the following species interactions
A Parasitism
B Mutualism
C Competition
D Predator/Prey
E Commensalism
1. Cheetahs and antelope ____
2. Mycorrihizae and plant roots ____
3.Humans and Tapeworms ____
4. A hawk eats a mouse ___
5. Two birds fight over a nest ____
6. Which of the Following ecosystems does NOT use soar energy as its ultimate
energy source?
A Pond
B Deep-Sea Hydrothermal Vent
C Rain Forest
D Tundra
E Coniferous Forest
7. Salinization is a process that makes soil less productive because it…
A. Removes essential Nutrients
B. Lowers the pH
C. Increases the Salt Content
D. Makes the soil Waterlogged
E. Produces larger soil particles
8. Soils found in mid-latitude grasslands would be most accurately described as being…
A. A high acidic content with little organic matter
B. a deep layer of humus and decayed plant material
C. a layer of permafrost
D. a high content of iron oxides and very little moisture
E. a small amount of nutrients but an abundant decomposer food web
9. Math the following with the soil type it would have
A Dessert Soil
B Grassland Soil
C Tropical Rain Forest Soil
D Pine Forest Soil
E Deciduous Forest Soil
9 Soil that has a substantial organic layer, fire helps to break down plant material in this
layer ____
10 Soil comprised of littler and humus, this soil is acidic due to the accumulation of
needles ____
11 Soil is rocky, very dry, and contains almost no organic matter ____
12Soil is acidic and contains very little organic matter despite large plant populations
____
13 Soil is rich in humus and partially decayed leaves ____
14 Where is the majority of Earth’s freshwater? ________________________
15. What are the three major cells of atmospheric movement?
_____________________
Answers
1.D
2.B
3.A
4.D
5.C
6. B
7. C
8. B
9.B
10.D
11.A
12.C
13.E
14. Ice and snow
15. Polar Hadley Ferrel