Goal 5 - Ecology
ECOLOGY - Reading (pages 35-52, 54-55, 91-99, 100-101, 116-120)
Ecology
Deals with interactions among organisms
Interactions between organisms and the environment
Dependent on
Biotic factors -Effect of living organisms in the environment, both direct and indirect
Abiotic factors – effect of non-living – water, oxygen, light, temperature, soil, organic and inorganic nutrients
Light
Energy for all living things comes directly or indirectly from the sun
Aquatic environments – light is absorbed as it passes through water
Temperature
Vary with latitude and altitude (vertical distance above sea level)
Nearby geographic features
Ecology
Deals with interactions among organisms
Interactions between organisms and the environment
Dependent on
Biotic factors -Effect of living organisms in the environment, both direct and indirect
Abiotic factors – effect of non-living – water, oxygen, light, temperature, soil, organic and inorganic nutrients
Light
Energy for all living things comes directly or indirectly from the sun
Aquatic environments – light is absorbed as it passes through water
- Photic layer of water which has light
- Aphotic layer – no light
Temperature
Vary with latitude and altitude (vertical distance above sea level)
Nearby geographic features
Soil - An Important Factor
Soil and minerals
Soil –mostly smaller rock particles broken down from larger by water and wind weathering
Minerals in the soil dependent on the kind of rock from which it has been weathered
Soil – Topsoil
Uppermost layer
Organic matter (humus) and living organisms, plant roots, earthworms, and insects
Next layer – subsoil
Rock particles mixed with inorganic compounds
Including minerals
Bottom layer
Bits of rock broken off from the bedrock below
Types of soil
Sandy – largest particles - water drains too quickly
Clay – small particles – water drains too slowly
Silt – intermediate size
Soil –mostly smaller rock particles broken down from larger by water and wind weathering
Minerals in the soil dependent on the kind of rock from which it has been weathered
Soil – Topsoil
Uppermost layer
Organic matter (humus) and living organisms, plant roots, earthworms, and insects
- Humus – from decay of dead plants and animals
- Organisms of decay – fungi and bacteria
Next layer – subsoil
Rock particles mixed with inorganic compounds
Including minerals
Bottom layer
Bits of rock broken off from the bedrock below
Types of soil
Sandy – largest particles - water drains too quickly
Clay – small particles – water drains too slowly
Silt – intermediate size
What is the Biosphere?
Biosphere – portion of the earth where living things exist - divided into
1.Lithosphere – solid part of earths surface
2.Hydrosphere –water
3.Atmosphere – mass of air surrounding the earth
1.Lithosphere – solid part of earths surface
2.Hydrosphere –water
3.Atmosphere – mass of air surrounding the earth
Levels of Organization
Levels of Organization in the “Living World”
Population- all individuals of a particular species, which interbreed and live in the same area
Community – all the populations of different organisms in a particular area
Ecosystem – community + it’s physical environment (abiotic factors)
Ecosystems contain….
Autotrophs– make their own food using carbon dioxide, water and the suns energy (photosynthesis) – plants – Producers
Heterotrophs: consumers
Population- all individuals of a particular species, which interbreed and live in the same area
Community – all the populations of different organisms in a particular area
Ecosystem – community + it’s physical environment (abiotic factors)
Ecosystems contain….
Autotrophs– make their own food using carbon dioxide, water and the suns energy (photosynthesis) – plants – Producers
Heterotrophs: consumers
- Herbivores (plant eating)
- Carnivores (meat eating)
- Omnivores (both plant and animal eaters)
- Predators (attack and kill prey)
- Decomposers – bacteria, fungus
- Scavengers – (feed on dead animals); Saprobes (break down remains of dead organisms)
Symbiotic Relationships
Symbiotic relationships - Two different organisms live in close association
Habitat- each organism has a particular place where it lives
Niche – particular role in an ecosystem. It’s job.
- Mutualism – both organisms benefit
- Commensalism –one organism benefits and the other is not affected
- Parasitism - One organism benefits (parasite) and the other is harmed (host)
Habitat- each organism has a particular place where it lives
Niche – particular role in an ecosystem. It’s job.
Flow of Matter and Energy
Flow of Matter and Energy in Ecosystems
Food chains and food webs – show feeding relationships
Energy stored in organic nutrients (of producers) is transferred to consumers
Herbivores – first order consumers (1st order hetertroph)
Carnivores – second order consumers (2nd order hetertroph)
Food chains and food webs – show feeding relationships
Energy stored in organic nutrients (of producers) is transferred to consumers
Herbivores – first order consumers (1st order hetertroph)
Carnivores – second order consumers (2nd order hetertroph)
Trophic Levels
Trophic Level
Each organism in a food chain represents a feeding step or trophic level.
Each organism in a food chain represents a feeding step or trophic level.
Food Web
Food webs
Show multiple feeding relationships
Show multiple feeding relationships
Pyramid of Energy
Pyramid of Energy
Amount of energy available at each level decreases with each higher feeding level
Usually 10% of energy (biomass) transferred at each level
Amount of energy available at each level decreases with each higher feeding level
Usually 10% of energy (biomass) transferred at each level
Pyramid of Biomass
Pyramid of Biomass
Biomass is the total weight of living matter at each trophic level.
Each level in the pyramid of biomass represents the amount that the level above needs to consume to meet its needs.
Biomass is the total weight of living matter at each trophic level.
Each level in the pyramid of biomass represents the amount that the level above needs to consume to meet its needs.
Pyramid of Numbers
Pyramid of Numbers
Each level in the pyramid of numbers represents the number of organisms consumed by the level above it.
Shows that population sizes decrease at each higher trophic level.
Each level in the pyramid of numbers represents the number of organisms consumed by the level above it.
Shows that population sizes decrease at each higher trophic level.
Biogeochemical cycles
Materials recycle between living things and the environment
Nitrogen, carbon, oxygen, and water
Carbon and Oxygen cycle
Carbon - .03% of atmosphere, dissolved waters of the ocean, converted by plants into organic compounds during photosynthesis
Oxygen – 20% of atmosphere – released into atmosphere during photosynthesis and removed by cellular respiration
During photosynthesis, plants combine carbon dioxide from the air and hydrogen from water to make carbohydrates. Some of these carbohydrates are stored in the tissues of the plant. Others are used by the plant for energy.
When that plant is eaten, the cells of the animal break down the plant's tissues during digestion. This releases the stored carbon and other nutrients into the animal's system.
As the animal breathes out (exhales), carbon dioxide is released into the air (atmosphere) and the cycle can begin again. This is known as respiration.
Respiration is not the only way carbon makes it into the air (atmosphere). Carbon and/or carbon dioxide is also released when dead plants and animals are decomposed and when fossil fuels are burned.
Materials recycle between living things and the environment
Nitrogen, carbon, oxygen, and water
Carbon and Oxygen cycle
Carbon - .03% of atmosphere, dissolved waters of the ocean, converted by plants into organic compounds during photosynthesis
Oxygen – 20% of atmosphere – released into atmosphere during photosynthesis and removed by cellular respiration
During photosynthesis, plants combine carbon dioxide from the air and hydrogen from water to make carbohydrates. Some of these carbohydrates are stored in the tissues of the plant. Others are used by the plant for energy.
When that plant is eaten, the cells of the animal break down the plant's tissues during digestion. This releases the stored carbon and other nutrients into the animal's system.
As the animal breathes out (exhales), carbon dioxide is released into the air (atmosphere) and the cycle can begin again. This is known as respiration.
Respiration is not the only way carbon makes it into the air (atmosphere). Carbon and/or carbon dioxide is also released when dead plants and animals are decomposed and when fossil fuels are burned.
Populations
Human ecology
Relationship between humans and the environment
Human population growth
Year 2000 - 6 billion
Limiting factor - limits further growth - lack of food, disease, predators, space
Carrying capacity - size of a population that can be supported by an environment
Relationship between humans and the environment
Human population growth
Year 2000 - 6 billion
Limiting factor - limits further growth - lack of food, disease, predators, space
Carrying capacity - size of a population that can be supported by an environment
J Curve
Exponential Growth - The Human Population Curve
Exponential growth - J-shaped curve.
Exponential growth means that as the population gets larger, it grows at a faster rate.
Results in Unchecked growth.
Factors that Affect Human Population Growth Rate
Birthrate – number of live births per 1000 population in a given year
Death rate – number of deaths per 1000 population in a given year
Immigration – movement of individuals into a population
Emigration – movement of individuals out of a population
Exponential growth - J-shaped curve.
Exponential growth means that as the population gets larger, it grows at a faster rate.
Results in Unchecked growth.
Factors that Affect Human Population Growth Rate
Birthrate – number of live births per 1000 population in a given year
Death rate – number of deaths per 1000 population in a given year
Immigration – movement of individuals into a population
Emigration – movement of individuals out of a population
S Curve
Growth Influenced By Limiting Factors - “S-Shaped Curve”
Carrying capacity - number of organisms a population can hold.
When overshoot carrying capacity a limiting factor may come into effect (I.e. disease)
Carrying capacity - number of organisms a population can hold.
When overshoot carrying capacity a limiting factor may come into effect (I.e. disease)
Limits to Population Growth
What can limit growth of a population?
Lack of food, diseases, predators, lack of space (limiting factors)
Reproductive patterns or life history patterns
Rapid life history patterns – reproduce rapidly and produce many offspring over a very short period of time (mosquitoes).
Slow life history pattern – slow rate of reproduction and produce very few young. (Elephants, humans)
Lack of food, diseases, predators, lack of space (limiting factors)
Reproductive patterns or life history patterns
Rapid life history patterns – reproduce rapidly and produce many offspring over a very short period of time (mosquitoes).
- Typically occur among organisms from unpredictable environments.
- These organisms have small body size, mature rapidly, reproduce early, and short life span.
- Populations increase rapidly then decline when environmental conditions change or become unstable for life.
Slow life history pattern – slow rate of reproduction and produce very few young. (Elephants, humans)
- Species are large in size
- Organisms mature slowly, are long lived.
- Populations sizes are at or near the carrying capacity
Population Dispersal Factors
Two Types of Limiting Factors that Are Related to Population Dispersal
Density-dependant - include disease, competition, predators, parasites, and food.
Density-independent - can effect populations regardless of their density. Most are biotic such as volcanic eruptions, temperature, storms, drought, pesticides, and major habitat destruction.
Density-dependant - include disease, competition, predators, parasites, and food.
Density-independent - can effect populations regardless of their density. Most are biotic such as volcanic eruptions, temperature, storms, drought, pesticides, and major habitat destruction.
Other Factors Affect Population Growth
Other Factors that affect Population
Predators-prey relationships
Competition within a population - for resources food, water, space, mates
Crowding and stress - Stress symptoms include aggression, decrease in parental care, decreased fertility, and decreased resistance to disease
Predators-prey relationships
Competition within a population - for resources food, water, space, mates
Crowding and stress - Stress symptoms include aggression, decrease in parental care, decreased fertility, and decreased resistance to disease
Developed vs Non-Developed Countries
Population remains the same if the birth and the death rates are equal and there is no change from migration
Developed - death rate low - good medical care
Developing - birth rate high - population growth
Developed - death rate low - good medical care
Developing - birth rate high - population growth
Urbanization
Urbanization
Population moves to cities - destruction of farmlands to make housing
Over farming and overgrazing - fields without vegetation - soil removed by wind and water causing erosion
Population moves to cities - destruction of farmlands to make housing
Over farming and overgrazing - fields without vegetation - soil removed by wind and water causing erosion
Pollution
Pollution
Adding anything to the environment that makes it less fit for living things
Adding anything to the environment that makes it less fit for living things
- Noise pollution
- Pesticides - contaminates air, water, disrupts food chains - DDT
- Air pollution - sulfur dioxide (burning of coal) mixes with rain water to produce ACID RAIN; carbon monoxide and nitrogen oxides (car exhaust, industry)
- Water pollution - eutrophication - explosive growth of algae, uses up all the dissolved oxygen and the fish die
- Land pollution - sanitary landfill, burning refuse in incinerators
Exotic Species
Exotic Species
Introduction of a new species that is not native to the area into an ecosystem.
Cause trouble for native species.
When introduced they can grow at an exponential rate due to the fact that they are not vulnerable to local predators or competitors.
Examples: Kudzu in NC, sea lamprey into Great Lakes, goats into Santa Catalina Island
Introduction of a new species that is not native to the area into an ecosystem.
Cause trouble for native species.
When introduced they can grow at an exponential rate due to the fact that they are not vulnerable to local predators or competitors.
Examples: Kudzu in NC, sea lamprey into Great Lakes, goats into Santa Catalina Island
Restoring the Environment
Restoring the environment
Controlling pollution - car emissions and unleaded gasoline
Sewage treatment - breakdown sewage before it goes back to waterway
Recycling and reusing to avoid filling land fills
Conserving Natural Resources
Renewable -air, water, soil, and sunlight,
Nonrenewable - coal, oil, natural gas, metals, and minerals
Biological pest control – pheromones
Conserving wildlife- legal protection of endangered species
Conserving forests - reforestation
Conserving soil
Strip cropping - cover crops planted between strips of regular crops
Terracing - sides of hills
Contour farming - rows on slopes
Windbreaks - prevent wind erosion
Controlling pollution - car emissions and unleaded gasoline
Sewage treatment - breakdown sewage before it goes back to waterway
Recycling and reusing to avoid filling land fills
Conserving Natural Resources
Renewable -air, water, soil, and sunlight,
Nonrenewable - coal, oil, natural gas, metals, and minerals
Biological pest control – pheromones
Conserving wildlife- legal protection of endangered species
Conserving forests - reforestation
Conserving soil
Strip cropping - cover crops planted between strips of regular crops
Terracing - sides of hills
Contour farming - rows on slopes
Windbreaks - prevent wind erosion