What is an ecosystem All the living biotic

What is an ecosystem? Ø All the living (biotic) and nonliving (abiotic) parts of an environment as well as the interactions among them Ø Ecosystems may be aquatic (water) or terrestrial (land). Ø Interactions may include: - producers (obtain energy by making their own food; plants -photosynthesis) - consumers (obtain energy by consuming their food) - decomposers ( get energy by breaking down dead organisms and the wastes of living things); bacteria, fungi (mold, mushrooms, etc) , worms, termites, etc.

(The greatest amount of energy is available at the producer level. ) (With producers and consumers, 90 % of the energy available at each level is consumed/lost to the environment. Only 10% move up to the next trophic level.

If removed from the food web, which organism (s) would have the greatest impact on the overall food web? Explain.

The sun provides energy To sustain producers which are the foundation of all ecosystems. Produce food through photosynthesis http: //www. brainpop. com/games/foodchaingame/ “Food Chain Game”

Abiotic & Biotic Factors Abiotic Factors (nonliving) water - shelter sunlight - soil rocks - nutrients oxygen/air, nitrogen temperature/climate space, salinity, p. H Ø - Biotic Factors (living) - Food - grass - trees - animals, insects, - plants Ø - bacteria, fungi

Gizmo Lab: Food Chain

Worms, termites, fungi (mold, mushrooms, etc. ) In the diagram, 1. What are the decomposers? Producers? Consumers? 2. What organisms are competing for the same abiotic resources? 3. What is the source of energy that drives or sustains the ecosystem?

Can you think of a situation where an organism could be both a primary and secondary consumer? (not shown on this food web) 1. 2. What are the producers? primary consumers? secondary consumers? tertiary consumer? What organisms are competing for the same abiotic and biotic resources?

Phytoplankton = producers Zooplankton = primary consumers In the above ecosystem: 1. 2. 3. 4. What do algae and phytoplankton contribute? What is the role of the fungi? What is the role of bacteria? What does the rotting log contribute?

Biomass Energy Pyramid: Trophic Levels Page 3 of study guide 4 th trophic level 3 rd t trophic level 2 nd trophic level 1 st trophic level (kcal) 1. At what trophic level is there the greatest amount of energy available? 2. What percent of energy is used/lost at each trophic level of an energy pyramid? 3. What percent of energy is passed up to the higher trophic level? 4. If removed from the pyramid, which organism (s) would have the greatest impact on all organisms? Explain.

Food Web Analysis Use the diagram to respond to each of the following. 1. Identify the decomposer. What are the benefits of decomposers? 2. What other decomposers may be in every ecosystem but are not shown on this diagram? 3. Identify the primary consumers. Show what is being consumed. 4. Identify the tertiary consumer for each food chain. What does this consumer eat? 5. Is this a terrestrial or aquatic food web? Explain. 6. What happens when two or more organisms coexist in the same niche? Some worms are primary consumers and others (in soil) are decomposers. ) 7. Draw an overlapping terrestrial/aquatic food chain using at least one of the organisms shown on the diagram. Add an organism not on this food web.

In what way may farming affect this marine ecosystem?

http: //www. youtube. com/watch? v=C-lc. EXI 7 al 4 “The Nitrogen Cycle” 3: 56 The Role of Nitrogen in an Ecosystem

(photosynthesis) respiration http: //www. youtube. com/watch? v=C-lc. EXI 7 al 4 Brainpop “The Carbon Cycle” 1: 23

Ecosystem Hierarchy Ø Organisms: individuals of a species Ø Populations: groups of organisms of the same species Ø Communities: the interaction of different populations; communities live within an Ø Ecosystem: all of the abiotic and biotic parts of an ecosystem Ø Biosphere: all of Earth’s ecosystems

Hierarchy From Atoms to Ecosystems Levels from Largest to Smallest Ø Ø Ø Ø Ø Ecosystem Level Community Level Population Level Organism Level Organ System Level Organ Level Tissue Level Cellular Level Molecular Level Atomic Level

From Atoms to Biosphere

Ecosystem Organization

Organism (single one of species) Mushrooms Coyotes Polar Bears Prairie Dogs Snakes Elephants

4 Populations (same species) Ø Ø Elk Population Elephant Population Ø Ø Cacti Population Gorilla Population

Communities (many populations) What communities are present in each of these ecosystems? Marine (aquatic) Ecosystem Terrestrial Ecosystem Freshwater & Terrestrial Ecosystems Aquatic (estuary) Ecosystems

Ecosystems make up the biosphere. Earth is the only planet on which life exists. It consists of three components Lithosphere (Land), Hydrosphere (Water) and Atmosphere (Air). The life supporting zone of the earth where atmosphere, hydrosphere and lithosphere meet, interact and make life possible, is known as biosphere.

An Arctic Food Web Activity 1. 2. 3. 4. 5. What overlapping aquatic/terrestrial food chains are there in this ecosystem? What population, if removed, would have the greatest impact on the overall food web? If the water was highly contaminated, what organism/population would have the highest level of contamination? Which organism contributes dissolved oxygen to the water? Which organisms may compete for the same food source(s)?

How would the removal of algae from this arctic food web affect both the biotic and abiotic factors? Ø Abiotic Factors Affected Ø - dissolved oxygen decreases nutrients may go up or down more CO 2 in water may be more turbid temp. may change - animal plankton pop. decreases - Biotic Factors Affected - silverside pop. decrease - beluga whale pop. decrease - cod pop. Decreases - bacteria increase & use up dissolved oxygen **Every population is directly or indirectly affected

Biodiversity Ø A variety of species exist in all ecosystems. What are examples of biodiversity in our area? - plant biodiversity - insect biodiversity - animal biodiversity - fungi biodiversity - bacteria biodiversity

Disruptions to Ecosystems: The Human Factor

Disturbances to Physical (abiotic) or Biological (biotic) Components of Ecosystems Ø Disruptions lead to shifts in all populations. This changes the biodiversity of an ecosystem. Ø What disruptions may occur leading to a change in the physical (nonliving/abiotic) components in an ecosystem? http: //www. youtube. com/watch? v=ddlr. Gke. Ozs. I Lake Peigneur disaster 9: 54 1. What affect did this disaster have on the aquatic ecosystems? Terrestrial? 2. What affect did this disaster have on the terrestrial ecosystems? ** Include both biotic and abiotic factors when answering these two questions. 3. How would this disaster lead to possible “population shifts”? Be specific.

Disruptions to Physical (nonliving/abiotic) Components * * * Volcanic eruptions * Pollution Hurricanes * Clear cutting Fires * Floods Drought * Nuclear Bomb Habitat depletion (human and natural) - i. e. urban sprawl How could these events change nutrients, water, light, salinity, shelter, soil, temperature, climate, etc. in an ecosystem?

Disruptions to Biological (living/biotic) Components * Volcanic eruptions * Pollution (land & water) * Hurricanes * Urban Sprawl * Fires * Clear Cutting * Drought * Introduction of exotic ** Overharvesting (non native) species * Habitat depletion (human and natural) How could these events change the biological (living/biotic) components in an ecosystem?

Preventing Overharvesting Hunting seasons - Laws (ownership) Ø Laws against poaching - Size limitations Ø Limit on Numbers - Organizations Ø License required - Size/types of nets Ø Specific places - Limits on gender Ø Wildlife Reserves/National Parks Ø Tagging/Monitoring Programs (remote sensing) Ø Breeding Programs Ø Identification of Endangered Species Ø

How may volcanoes disrupt ecosystems? Ø Producers? Ø Consumers? Ø Biotic Factors? Ø Abiotic Factors?

Impact of Clear Cutting What are the impacts on biotic and abiotic factors?

Impact of Introducing Exotic Species: Kudzu is a serious invasive plant in the United States. It has been spreading in the southern U. S. at the rate of 150, 000 acres (61, 000 ha) annually, "easily outpacing the use of herbicide spraying and mowing, as well increasing the costs of these controls by $6 million annually. “ Its introduction has produced devastating environmental consequences. What do you think?

Impact of Introducing Exotic Species: Burmese python in Florida This snake was found in the Everglades National Park, measuring 17 feet, 7 inches and over 165 pounds. The other record broken was the fact the snake was pregnant with 87 eggs. There is believed to be thousands thriving the moist, hot climate of the Everglades perhaps released years ago by pet owners or from pet shops during Hurricane Andrew in 1992. Local ordinances prohibit the import of these reptiles and allowing them to be hunted has not put much of a dent on population control. They have the ability to swallow large animals’ whole after coiling around their prey and suffocating them. What do you think?

The Effect of the Brown Tree Snake in Guam _ _ _ What led to the dramatic loss of birds on Guam? Well this part of the story isn’t actually so “natural”— although it was unintentional. Sometime in the mid to late 1940 s, brown tree snakes were introduced to the island probably by hitching a ride on a cargo ship after World War II. Because there aren’t many large predators on Guam, the snakes quickly took over the island. By the 1980 s the birds were wiped out save for two colonies that continue to exist on a military base. To this day the snakes are still around (one of the attempts to control them involved dropping Tylenol-laced mice from airplanes). What happens to spiders when you remove birds from a tropical island? The researchers found that during the dry season Guam had 2. 3 times more spider webs than neighboring islands that still have birds. During the wet season the number of webs was a whopping 40 times higher on Guam. And the spider webs on Guam were much larger— 50% larger—than those on the other islands. Removing birds from the equation likely changed the Guam spider population in many ways including some (or all) of these scenarios: (1) since birds weren’t around to eat the spiders the spider population grew, (2) the spiders no longer had to compete with the birds to eat insects so more spiders survived and were able to reproduce, (3) the spiders didn’t have to keep spinning new webs because the birds weren’t there to mess them up anymore, so they built larger webs and put more energy into reproduction.

Population Density - the number of people/organisms living per unit of an area (e. g. per square mile); the number of people relative to the space occupied by them _ how full an area is: the concentration of people or things within an area in relation to its size

Limiting Factor Ø- environmental factors that limit population sizes in a particular ecosystem

Limiting Factors in an Ecosystem Ø Density-dependent Factors - operate more strongly on large populations and disease triggered by increases in population density (crowding) * Competition for food, water, shelter & space * Predation * Parasitism * Disease

Population Density: measures the number of individual organisms living in a defined space High Population Density China’s Qingdao Huiquan Beach

China’s Qingdao Huiquan Beach Low Population Density Compare this picture to the previous one. If these were animals, Ø How may the spread of disease and parasites be affected by the population densities? Ø How may competition for food, water, space and shelter be affected?

W What is the relationship between the hare population and the lynx population? Ø What role does competition play in this predator/prey relationship? Ø Why is competition important in an ecosystem? Ø

Density-independent Factors Ø Limiting factors that occur regardless of how large the population is and reduce the size of all populations in the area; mostly abiotic - weather changes human activities (pollution, urban sprawl, etc. ) natural disasters (i. e. fires)

Relationships Within Ecosystems: - Coexistence and cooperation - Competition (predator/prey) - Parasitism