Ecosystem
Biotic and abiotic parts (living and non living things)
System
Set of components that function and interact in some regular and theoretical predictable manner
Open System
A system that can exchange both matter and energy with its surroundings
Closed System
A system that allows the exchange of energy, but not matter, between the system and its surroundings.
Example of Open System
our planet, a lake, humans
Example of Closed System
Something inside of a closed jar without access to sunlight
How to calculate resident time
The capacity of a system to hold a substance DIVIDED BY the rate of flow of the substance through the system
ART
Size of reservoir DIVIDED BY rate of transfer (flow)
Feedback System
Cycle of events in which body's status is monitored, changed, and reevaluated
-System in which outputs from the system affect future inputs or future activities of the system.
Example of Positive Feedback System
Deforestation
Polar Ice Melt
Example of Negative Feedback System
Homeostasis
Thermostat
Steady State in a System
There is no net change in the environmental parameters (same in as out), but it doesn't mean that energy independent
Autotroph
-Producers
-Can convert solar energy into chemical energy
-An organism that makes its own food
Primary Consumer (Herbivores)
Gets energy by eating autotrophs/producers
Secondary Consumer (Carnivores)
Consume primary consumers/heterotrophs
Scavenger
A carnivore that feeds on the bodies of dead organisms
Decomposer
organism that breaks down and obtains energy from dead organic matter
-help recycle nutrients
Biota
plants and animals living in a region
Omnivores
eat producers/consumers
Community
Population of different organisms in an area
Biosphere
part of air, water, and soil where life is found
Population
A group of individuals of the same species living in a given area
Species
A group of organisms that can interbreed in nature and produce a fertile offspring
Ecology
The study of how living things interact with each other and their environment
Components of an ecosystem
1) Abiotic Environment
2) Producers/Autotrophs
3) Consumers/Heterotrophs
4) Detrivores and Decomposers
Detrivore
Breaks down dead tissue
Food Chain
A community of organisms where each member is eaten in turn by another member
Food Web
A community of organisms where there are several interrelated food chains
Know factors that you need to understand to better manage an ecosystem
-gravity
-cycle of nutrients
-source of energy
GPP
-Gross Primary Production
-rate at which an ecosystem's producers convert solar energy into chemical energy
NPP
-Net Primary Productivity
-energy captured minus the energy respired by producers
How to calculate Trophic Level Efficiencies
Divide lower level by level above, multiply by 100
Biogeochemical Cycle
the circulation of substances through living organisms from or to the environment
Water Cycle
-The continuous cycle of the transfer of water through an ecosystem, which involves evaporation, transpiration, and precipitation
-Sun drives water cycle
-Most goes into streams, which carries into lakes and oceans
-Some seeps into upper layers of soil
-S
Carbon Cycle
-The process in an ecosystem in which producers take in carbon dioxide from the atmosphere during photosynthesis and consumers, having eaten producers, release carbon into the atmosphere as carbon dioxide
-Carbon Dioxide increases in atmosphere because
i.
Nitrogen Cycle
The transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to the atmosphere
Processes of Nitrogen Cycle
-Nitrogen Fixation
-Assimilation
-Ammonification
-Nitrification
-Denitrification
-Lightning and Fertilizer Production
FAANDL
Nitrogen Fixation
Converting nitrogen into a form that can be used by living organisms
Assimilation
-Producers take up Ammonia and use nitrogen to make proteins/nucleic acids
-Consumers get it by consuming producers
Ammonification
-Turns Ammonia into Ammonium
-Done by Decomposers in soil and water
Nitrification
-Nitrifying Bacteria
-turns Ammonium into Nitrite into Nitrate
Denitrification
Done by denitrifying bacteria into poor soils/stagnant water
-Nitrate into Nitrite into Nitrogen
Lightening and Fertilizer Production
Converts some nitrogen into nitrate
Phosphorous Cycle
a. Nucleic acids
b. No atmospheric component
c. Guano: bird poop
d. Animal waste
e. Limiting mineral: minerals that limit the growth of plants in nature
f. Phosphate is a limited mineral in water
i. If phosphate is not limiting (due to sewage or fertilize
Eutrophication
As a result of phosphoric runoff, algal growth in a body of water increases, reducing the amount of sunlight that reaches the organisms in the water and therefore, the organisms die
-CWA
Sulfur Cycle
Cyclic movement of sulfur in different chemical forms from the environment to organisms and then back to the environment
a. Proteins
b. Sulfur Dioxide increases by extraction/refining and burning of fossil fuels
c. SO2 combines with water to make acid rai
Types of Interactions Between Species
Predation
Parasitism
Commensalism
Mutualism
Interspecific Competition
CIMPP
Predation
One predator eats a prey
Example of predation
Lions eat Zebras
Parasitism
Parasites live either in or on host
Example of parasitism
Tapeworm
Commensalism
One species benefits, the other species neither benefits nor harmed
Example of Commensalism
Sharks and pilotfish
Mutualism
Benefits both species
Example of Mutualism
Nitrogen fixing bacteria in plants
Interspecific Competition
Two species compete for the same resource
Example of Interspecific Competition
Chipmunks, Squirrels, and other animals fight for the pine nut
Fundamental Niche
Range at which the species can thrive
-WHAT IT IS CAPABLE OF
Realized Niche
Range of both biotic and abiotic factors at which a species actually lives
-WHAT ACTUALLY HAPPENS
Interference
Two species with the same fundamental niche in a given area, battling for the same resource
Exploitation Competition
Same thing as Competitive Exclusion Principle
Competitive Exclusion Principle
States that no two species can occupy the same niche in the same habitat at the same time; ONE OF THE SPECIES WILL DIE OUT
Resource Partitioning
Two species divide resources based on specific behavior
Types of Populations
Clumped
Uniform
Random
Clumped Population
Social animals animals that live in packs like wolfs so they hunt in packs
Uniform Population
Implies a regularity of distance between and among individuals of a population
Random Population
scattered-dandelions
Limiting Factor Principle
Too much or too little of a factor can limit or prevent growth, EVEN if all other factors are near the optimum level of tolerance
-LIMIT OF TOLERANCE
Two Types of Ecological Succession
Primary and Secondary
Ecological Succession
Changes over time
Primary Succession
Occurs on surfaces that are initially devoid of soil
-Example: Cooled Lava
Secondary Succession
Areas that have been disturbed, but have not lost their soil
-Example: cotton fields after civil war
Inertia
can't come back after destruction
Resilience
ability to come up after destruction
Environmental Science
study of interactions between systems found in nature
Demography
the study of populations and their growth
Doubling Time
Amount of time it takes to double the size of a population
70 divided by annual rate growth
Total Impact of Population on an Environment Formula
Impact = Population TIMES Affluence TIMES Technology
I = PAT
Density Formula
Impact = (Population/Size of Place) TIMES (Technology)
What is the difference between the effect of an individual in an industrialized nation and a developing nation?
Industrialized: more technology, more affluence; people have larger ecological footprints: use more resources, waste more resources - lower birth rate, lower death rate, longer life expectancy;
Developing: use fewer resources
Stages of Population Growth
Stage 1: Hunters/Gatherers - beginning of humans
Population: .25 -.5 million
Stage 2: Early Pre-Industrial Agriculture
Population: 100 million
Stage 3: Machine Age (death rate decline, sanitation incline)
Population: 900 million
Stage 4: Modern Era
Popula
Pros of Reducing Birth Rate
More resources per capita
Less poverty
Less pollution, smaller footprint
Cons of Reducing Birth Rate
Less youth to support elderly
Labor shortage
Old people don't help the economy
Indicators of Urban Sustainability
1. Children
2. Violent crime
3. Access to healthcare
4. Air and water quality
5. Vacant or abandoned housing
6. Participation in neighborhood societies
7. Access to public transportation
8. Shopping and services within walking distances
9. Quality of scho
Advantages of Urbanization
1. Economic opportunities
2. Better healthcare; lower infant mortality rate
3. Better educational/social opportunities
Biodiversity
variety of earth's species
Ecosystem Diversity
various ecosystems within a region
Species Diversity
various species within an ecosystem
Genetic Diversity
variety of genes within a species
Natural Selection
the process by which the organisms better adapted to their environment tend to survive and produce more offspring
Genetic Resistance
ability of one or more members of a population to resist a chemical designed to kill it
Adaptive Genetic Traits
must precede change in the environmental conditions
Reproductive capacity
species that reproduce rapidly and in large amounts are better able to adapt
Genetic Drift
change in genetic composition due to random events
Founder's Effect
change in population descended from a small number of colonizing individuals
Bottleneck Effect
a decrease in genetic diversity due to a random event
Example: tsunami with few survivors creates a non-representative genetic population
Speciation
One species splits into two or more species
Allopatric Speciation
The formation of new species in populations that are geographically isolated from one another.
Geographic Isolation
happens first; physical isolation of populations for a long period of time
Reproductive Isolation
mutations and natural selection in geographically isolated population lead to inability to produce viable offspring when members of 2 different populations
Example of Allopatric Isolation
Fox population moves north and now needs thicker fur, higher fat content, etc.; those who do not adapt will die out/ Fox population moves south and now needs thinner fur, lean body, etc; eventually become so different (^) that they cannot reproduce
Sympatric Speciation:
Evolution of 1 species into 2 or more species without geographic isolation
Polyploidy
having extra sets of chromosome; Example: banana (triploid/grown in cuttings), bread wheat (hexaploid)
* ONLY VIABLE IN PLANTS
Components of Species Diversity
species richness and species evenness and relative abundance
Nonnative
Introduced by accident or deliberately into an ecosystem;
Example: Kudzu
Indicator
Give early warning of ecosystem change; Example: deformed frogs
Species Diversity
major component of biodiversity and tends to increase the sustainability of ecosystems