Energy From sun or chemicals Raw materials to make building blocks of life From food
Sunlight is the main energy source for life on Earth Autotrophs will use energy from the sun to convert carbon dioxide and water into oxygen and carbohydrates (photosynthesis!) 6CO 2 + 6H 2 O C 6 H 12 O 6 + O 2 Autotrophs are also known as producers Examples: Plants Algae Cyanobacteria
What if there is no light in the ecosystem? The autotrophs will use chemosynthesis, which is a process that uses chemical energy to produce carbohydrates (ex: bacteria living in volcanic vents)
Organisms that rely on other organisms for energy are known as consumers or heterotrophs Herbivores- consume only plants s- consume only meat Omnivores- consume both plants and animals Detritivores- consume plant and animal remains (earthworms, mites, crabs) Decomposer= breaks down organic matter to obtain energy (bacteria & fungi)
Energy in an ecosystem flows in one direction (from sun to the heterotrophs) Food chain- a series of steps in which organisms transfer energy by eating and being eaten Each step in a food chain or food web is called a trophic level Autotrophs make up the first trophic level, consumers make up 2nd, 3rd, 4th or higher level
Producers Base of all food chains Autotrophic (manufacture organic molecules) Energy source does not come from other living things (i.e. sunlight or chemical energy) Raw materials Inorganic compounds (i.e. CO 2, H 2 S, H 2 O) Examples: Photosynthetic organisms (i.e. plants, algae, cyanobacteria) Chemosynthetic organisms (i.e. archae-bacteria in deep ocean vents) Detritivores Heterotrophic Utilize energy and raw materials from dead or decaying organisms End of all food chains Decomposers Reduce organic molecules to inorganic compounds Examples: worms, bacteria, fungi, termites Consumers Heterotrophic Utilize energy and raw materials obtained from other living things Herbivores = Primary Consumers Acquire energy by ingesting autotrophic organisms (usually plants) Examples: rabbits, deer, bees s Predators & scavengers Secondary Consumers Acquire energy from flesh of herbivores Tertiary Consumers Acquire energy from flesh of other carnivores Examples: lions, snakes, hawks
Sun Energy Energy Producers obtain energy from sunlight or chemicals. Energy flows in one direction through trophic levels. Primary Producers (plants, algae cyanobacteria) Primary Consumers (herbivores) Secondary Consumers (carnivores) Detritus Detritivores (bacteria, fungi, etc.)
Sun Nutrients Energy Producers obtain energy from sunlight or chemicals. Energy flows in one direction through trophic levels. Nutrients Producers build organic molecules using inorganic compounds found in soil or water. Decomposers break organic molecules down into inorganic compounds, which are released into soil or water. Nutrients are recycled by producers Primary Producers (plants, algae cyanobacteria) Primary Consumers (herbivores) Secondary Consumers (carnivores) Detritus Inorganic Nutrients Detritivores (bacteria, fungi, etc.)
Sun Energy Nutrients Energy Producers obtain energy from sunlight or chemicals. Energy flows in one direction through trophic levels. Nutrients Producers build organic molecules using inorganic compounds found in soil or water. Decomposers break organic molecules down into inorganic compounds, which are released into soil or water. Nutrients are recycled by producers Primary Producers (plants, algae cyanobacteria) Primary Consumers (herbivores) Secondary Consumers (carnivores) Detritus Inorganic Nutrients Detritivores (bacteria, fungi, etc.)
Sun 90% of energy lost as heat Producers Energy transferred to consumers 90% of energy lost as heat NUTRIENT CYCLING Consumers (herbivores, predators, parasites, detritivores) Physical environment Decomposers break down the remains of dead organisms, returning the inorganic nutrients to the environment Only about 10% of energy is transferred to organisms at the next trophic level If 10% of solar energy is captured by plants then animals who eat the grass gain only 10% of that energy (1%), animals who those animals gain 10% from that (.1%) 10% --> 1% -->.1%
Is all the energy that the plant obtains from the sun transferred to a mouse? NO! Energy is needed for life! (The plant uses some of the energy for life processes, such as cellular respiration, growth, reproduction, etc )
10% of energy is transferred 10% 10% Trophic Level Tertiary Consumers Energy 10 kcal Secondary Consumers Primary Consumers 100 kcal 1,000 kcal Producers 10,000 kcal
CARNIVORES Quaternary consumers Tertiary consumers Secondary consumers Herbivore Primary consumers Zooplankton HERBIVORES Plant TERRESTRIAL FOOD CHAIN Primary producers Phytoplankton MARINE FOOD CHAIN PLANTS
Quaternary consumers Tertiary consumers Secondary consumers Primary consumers Herbivore Zooplankton Plant TERRESTRIAL FOOD CHAIN Primary producers Phytoplankton MARINE FOOD CHAIN FOOD CHAIN
Quaternary Consumers (s) Osprey Bald Eagle Tertiary Consumers (s) Gulls & Terns Wading Birds Large Piscivorous Fish Sea Ducks Tundra Swan Secondary Consumers (s) Small Plankivorous Fish Bivalves Primary Consumers (Herbivores) Zooplankton Benthic Invertebrates Herbivorous Ducks Geese & Mute Swans Producers Phytoplankton Aquatic Vegetation Vegetation
Energy 90% of energy contained in living tissue is lost as heat or waste as it passes from one trophic level to the next. Only 0.1% of energy made by Producers reaches Tertiary Consumers Only 1% of energy made by Producers reaches Secondary Consumers Only 10% of energy made by Producers reaches Primary Consumers Producers manufacture 100% of biological energy.
Numbers As energy flows up Through the trophic levels, fewer individuals can be supported at each level. 1 Fox 25 Birds 250 Grasshoppers 3000 Grasses
Biomass Total weight of all the living organisms within the trophic level. The biomass that can be supported decreases as energy flows up through trophic levels. 1 kilogram of human tissue 10 kilograms of beef 100 kilograms of grain
Humans 20,000 kcal from grain will supply 2,000 kcal of beef enough to feed 1 person for 1 day. 20,000 kcal from grain will feed 10 people for 1 day. Cattle Humans Grains Grains
Eagle = DDT Turtle Turtle Turtle Fish Fish Fish Fish Fish Fish Fish Fish Fish
Bioaccumulation & Biomagnification Human 1,000 X (???) 1. Toxins are washed into water and build up in sediment and plant life. 5 2. Bottom-dwelling animals like zebra mussels concentrate the toxins when they eat phytoplankton & algae. 3. Gobies and other small fish ingest the toxins when they feed on the zebra mussels. Small mouth bass 200X 4 4. Predator species like bass continue to concentrate toxins by eating the small fish. 1 2 3 Goby 40X 5. Humans then ingest the toxins when we eat the larger fish (bass, perch, walleye, etc.). Green algae X Zebra mussels 5X