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Science 10 - Ecosystems. Ecosystem – includes all the organisms in an area that interact with each other and with their non-living environment. ex. Ocean Ecosystem Desert Rain Forest. Factors Affecting Ecosystems 1) Biotic Factors – living things. ex. Organisms.
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Ecosystem – includes all the organisms in an area that interact with each other and with their non-living environment. ex. Ocean Ecosystem Desert Rain Forest
Factors Affecting Ecosystems 1) Biotic Factors – living things. ex. Organisms
2. Abiotic Factors – non-living eg. Sunlight, wind, temperature, etc.
Biome – a large geographic area with a characteristic climate (ex. tropical rain forest). Biosphere – 3 regions on earth in which all life exists. a. Lithosphere – solid portion of earth’s surface.
b. Hydrosphere – layer of water which covers ¾ of earth’s surface.
Cycles of Life • All life requires nutrients and nutrients are continuously recycled…if they were not, they would become used up and life on Earth would cease to exist.
Carbon Cycle • Photosynthesis and cellular respiration make up the stages of the carbon cycle. • Carbon is absorbed by plants (as CO2) which then release O2 back into the atmosphere. This CO2 is converted into chemical energy [carbohydrates (sugars starches)]. • Animals eat the plants and these sugars/starches are used to provide energy. The product released back to the atmosphere is CO2 and the cycle is complete. • Carbon is still present in the bodies of plants and animals and will be recycled by decomposers, which also use O2 and return Carbon into the atmosphere in the form of CO2.
This cycle has become unbalanced due to the burning of fossil fuels. • During the Carboniferous Period (a. 300mya) large amounts of Carbon (in the tissues of plant matter) was trapped under ground. • Because of lack of oxygen and tremendous pressure, the plant matter was compressed into fossil fuels (coal, natural gas, and oil) • Burning these for energy releases CO2 into the atmosphere; too much for plants to use…causing an unbalanced C-cycle. • Large amounts of the carbon cycle takes place in Earth’s oceans but if the temperature of the oceans increases, more CO2 will escape back into the atmosphere (increase in temp. = decrease in solubility of a gas = CO2).
Nitrogen Cycle • Plants use N, P, & K for growth and development (these are the main ingredients in fertilizers). • Nitrogen gas makes up about 80% of Earth’s atmosphere but most organisms cannot absorb nitrogen directly. • Nitrogen fixation – is when nitrogen gas is converted into compounds (NH4+ & NO3-) that can be used by plants. Animals get Nitrogen by eating the plants.
Nitrogen fixing bacteria – are some of the few species that convert nitrogen into useable compounds • Nitrogen in these compounds will pass through the plants to the animals then to the soil and water through wastes and dead organisms • These compounds can reenter plants before going back to the atmosphere, creating a cycle within a cycle • Decomposers (bacteria) will break down the wastes/dead organisms and produce Ammonia which is converted back into Nitrates for use by the plants by Nitrifying bacteria. • This process is called nitrification. Denitrifying bacteria – convert nitrates in the soil or water back into nitrogen gas = denitrification.
This cycle can also be altered by humans. E.g. Adding too much fertilizers to soils causes root damage, stunts growth, and increases soil acidity. • The build up of nitrogen and other nutrients in aquatic ecosystems is called eutrophication – this increases plant growth at the water’s surface, not allowing sunlight to get to deeper waters and therefore “strangles” plants and animals because photosynthesis cannot take place in the deeper waters.
Water Cycle Assignment: Define the following. • Evaporation • Transpiration • Condensation • Precipitation • Surface Runoff • Percolation • Ground Water • Water Table • Respiration
How Energy is Transferred in an Ecosystem 1. Producers (Autotrophs) – green plants that convert radiant energy into chemical energy (photosynthesis).
2. Consumers (Heterotrophs) – consume other organisms. a) Primary Consumer (Herbivore) – animals that eat plants.
b) Secondary Consumer (Carnivore) – animals that feed on plant eaters.
c) Decomposers – organisms (generally fungus and bacteria) that obtain energy from breaking down remains or wastes of other organisms. Green plants produce more energy per unit of land area and only a portion of this energy is passed on to consumers that eat plants. Thus animals and animal products contain less energy than plants on the same amount of land.
Feeding Levels - Food chains are made up of several feeding (energy) levels we call Trophic Levels.
Producer Leaves 1stTrophic Level Primary Consumer Caterpillar 2ndTrophic Level Herbivore Secondary Consumer Robin 3rdTrophic Level Carnivore Tertiary Consumer Eagle 4thTrophic Level Top Carnivore Quaternary … Detritivores and Decomposers
only 5-20% of energy is passed from one trophic level to another. • Most of the usable energy at each level is converted to thermal (heat) energy and waste matter. • Energy remains in the tissues of dead organisms which is used by detritivores and scavengers.
Detritivores – feed on bodies of smaller dead animals. Dead plant matter, and animal dung. ex. Crabs, earthworms, wood beetles, ants
Decomposers – bacteria and fungi which break down the cells and extract the last remaining energy. Maggots Saprobes
FOOD CHAIN - an autotroph is producer is eaten by a primary consumer and its food energy is transferred to a secondary consumer who is gobbled up by a tertiary consumer and eventually its energy is transferred to the top consumer of this food chain. This is only a small part of a food web within the ecosystem. P. 829 ** arrows go from food to eater (don’t draw animal pictures.) eg. shrub rabbits cougar BIOLOGICAL MAGNIFICATION = increasing amounts of toxins like DDT or mercury as you follow a food chain from producer to top consumer. Video Energy Flow in the Ecosystem
FOOD CHAIN - an autotroph or producer is eaten by a primary consumer and its food energy is transferred to a secondary consumer who is gobbled up by a tertiary consumer and eventually its energy is transferred to the top consumer of this food chain. This is only a small part of a food web within the ecosystem. P. 829 ** arrows go from food to eater (don’t draw animal pictures.) eg. shrub rabbits cougar BIOLOGICAL MAGNIFICATION = increasing amounts of toxins like DDT or mercury as you follow a food chain from producer to top consumer. Video Energy Flow in the Ecosystem
FOOD CHAIN - an autotroph or producer is eaten by a primary consumer and its food energy is transferred to a secondary consumer who is gobbled up by a tertiary consumer and eventually its energy is transferred to the top consumer of this food chain. This is only a small part of a food web within the ecosystem. P. 829 ** arrows go from food to eater (don’t draw animal pictures.) eg. shrub rabbits cougar BIOLOGICAL MAGNIFICATION = increasing amounts of toxins like DDT or mercury as you follow a food chain from producer to top consumer. Video Energy Flow in the Ecosystem
FOOD CHAIN - an autotroph is producer is eaten by a primary consumer and its food energy is transferred to a secondary consumer who is gobbled up by a tertiary consumer and eventually its energy is transferred to the top consumer of this food chain. This is only a small part of a food web within the ecosystem. P. 829 ** arrows go from food to eater (don’t draw animal pictures.) eg. shrub rabbits cougar BIOLOGICAL MAGNIFICATION = increasing amounts of toxins like DDT or mercury as you follow a food chain from producer to top consumer. Video Energy Flow in the Ecosystem
FOOD CHAIN - an autotroph is producer is eaten by a primary consumer and its food energy is transferred to a secondary consumer who is gobbled up by a tertiary consumer and eventually its energy is transferred to the top consumer of this food chain. This is only a small part of a food web within the ecosystem. ** arrows go from food to eater (don’t draw animal pictures.) eg. shrub rabbits cougar BIOLOGICAL MAGNIFICATION = increasing amounts of toxins like DDT or mercury as you follow a food chain from producer to top consumer. Video Energy Flow in the Ecosystem
FOOD CHAIN - an autotroph is producer is eaten by a primary consumer and its food energy is transferred to a secondary consumer who is gobbled up by a tertiary consumer and eventually its energy is transferred to the top consumer of this food chain. This is only a small part of a food web within the ecosystem. ** arrows go from food to eater (don’t draw animal pictures.) eg. shrub rabbits cougar BIOLOGICAL MAGNIFICATION = increasing amounts of toxins like DDT or mercury as you follow a food chain from producer to top consumer. Video Energy Flow in the Ecosystem
BIOLOGICAL MAGNIFICATION = increasing amounts of toxins like DDT or mercury as you follow a food chain from producer to top consumer
ENERGY PYRAMIDS -the base if the pyramid is the first trophic level (always a producer) -the trophic levels above continue to be numbered upwards (Handout has ______ trophic levels) -there are energy pyramids which represent the transfers of energy in a food chain and there are pyramids of biomass. (=2 kinds of pyramids) -biomass = the mass of all organisms in a trophic level that compete for the same food. -competition = organisms can compete in the communities for food, habitat space, and other resources. No two populations can occupy the same niche (ones got to go) = competitive exclusion principle
PYRAMIDS -the base of the pyramid is the first trophic level (always a producer) -the trophic levels above continue to be numbered upwards (Handout has ______ trophic levels) -there are energy pyramids which represent the transfers of energy in a food chain and there are pyramids of biomass. (=2 kinds of pyramids) -biomass = the mass of all organisms in a trophic level that compete for the same food. -competition = organisms can compete in the communities for food, habitat space, and other resources. No two populations can occupy the same niche (ones got to go) = competitive exclusion principle
PYRAMIDS -the base if the pyramid is the first trophic level (always a producer) -the trophic levels above continue to be numbered upwards (Handout has ______ trophic levels) -there are energy pyramids which represent the transfers of energy in a food chain and there are pyramids of biomass. (=2 kinds of pyramids) -biomass = the mass of all organisms in a trophic level that compete for the same food. -competition = organisms can compete in the communities for food, habitat space, and other resources. No two populations can occupy the same niche (ones got to go) = competitive exclusion principle
PYRAMIDS -the base if the pyramid is the first trophic level (always a producer) -the trophic levels above continue to be numbered upwards (Handout has ______ trophic levels) -there are energy pyramids which represent the transfers of energy in a food chain . There are pyramids of biomass & numbers. (=2 kinds of pyramids) -biomass = the mass of all organisms in a trophic level that compete for the same food. -competition = organisms can compete in the communities for food, habitat space, and other resources. No two populations can occupy the same niche (ones got to go) = competitive exclusion principle
What two ecosystems in the world have the greatest biomass ?
ENERGY PYRAMIDS -the base if the pyramid is the first trophic level (always a producer) -the trophic levels above continue to be numbered upwards (Handout has ______ trophic levels) -there are energy pyramids which represent the transfers of energy in a food chain . There are pyramids of biomass & numbers. (=3 kinds of pyramids) -biomass = the mass of all organisms in a trophic level that compete for the same food. -competition = organisms can compete in the communities for food, habitat space, and other resources. No two populations can occupy the same niche (ones got to go) = competitive exclusion principle
ENERGY PYRAMIDS -the base if the pyramid is the first trophic level (always a producer) -the trophic levels above continue to be numbered upwards (Handout has ______ trophic levels) -there are energy pyramids which represent the transfers of energy in a food chain . There are pyramids of biomass & numbers. (=3 kinds of pyramids) -biomass = the mass of all organisms in a trophic level that compete for the same food. -competition = organisms can compete in the communities for food, habitat space, and other resources. No two populations can occupy the same niche (ones got to go) = competitive exclusion principle
ENERGY PYRAMIDS -the base if the pyramid is the first trophic level (always a producer) -the trophic levels above continue to be numbered upwards (Handout has ______ trophic levels) -there are energy pyramids which represent the transfers of energy in a food chain . There are pyramids of biomass and numbers. (=3 kinds of pyramids) -biomass = the mass of all organisms in a trophic level that compete for the same food. -competition = organisms can compete in the communities for food, habitat space, and other resources. No two populations can occupy the same niche (ones got to go) = competitive exclusion principle
Releases toxins Into the soil to Prevent other plant growth = competition
ENERGY PYRAMIDS -the base if the pyramid is the first trophic level (always a producer) -the trophic levels above continue to be numbered upwards (Handout has ______ trophic levels) -there are energy pyramids which represent the transfers of energy in a food chain . There are pyramids of biomass and numbers. (=3 kinds of pyramids) -biomass = the mass of all organisms in a trophic level that compete for the same food. -competition = organisms can compete in the communities for food, habitat space, and other resources. No two populations can occupy the same niche (one’s got to go) = competitive exclusion principle