Ecosystem Dynamics. Ecology and Levels of Organization. Slide 2 / 93. Slide 1 / 93. Slide 4 / 93. Slide 3 / 93. Slide 5 / 93.

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1 Slide 1 / 93 Slide 2 / 93 New Jersey Center for Teaching and Learning Progressive Science Initiative This material is made freely available at and is intended for the non-commercial use of students and teachers. These materials may not be used for any commercial purpose without the written permission of the owners. NJCTL maintains its website for the convenience of teachers who wish to make their work available to other teachers, participate in a virtual professional learning community, and/or provide access to course materials to parents, students and others. Click to go to website: Ecosystem Dynamics Slide 3 / 93 Slide 4 / 93 Table of Contents Ecology and levels of organization Ecosystems Ecosystem Interactions Click on the topic to go to that section Ecology and Levels of Organization Altering Ecosystems Return to Table of Contents Slide 5 / 93 Slide 6 / 93 Ecology Ecology Ecology is the study of the interactions between organisms and their environment. This picture includes one squirrelfish (red), two cleaner wrasse (little blue-striped fish) and some coral. What interactions can you observe in this picture? The squirrelfish is being cleaned by the cleaner wrasse. The cleaner wrasse are being protected by the squirrelfish. All of the fish are being protected by the coral. Organisms are able to interact with living and nonliving aspects of their environment.

2 Slide 7 / 93 Levels of Organization Slide 8 / 93 Species Scientists often classify living things into different kinds of groups. Species Population (smallest) Species is a group of organisms that share common characteristics. Individuals within a species are only able to breed with others from the same species. Examples of different species include the following: Community In an ecosystem, classifications are known as levels of organization. Ecosystem Biome Panda Bald Eagle Blue Spruce Biosphere (largest) Slide 9 / 93 Population A population is a group of the same species living in the same place, at the same time. Slide 11 / 93 Ecosystem Blue and gold snappers are found in the Pacific, from Mexico down to Ecuador. Although they are all the same species, a group of snappers that live off the coast of Ecuador is a different population than a group that live off the coast of Mexico. An ecosystem includes all of the living and nonliving factors that exist in a community. Slide 10 / 93 Community A community is composed of all the different populations of species that live together in a given area. This deciduous forest community is composed of lots of different populations: trees deer fungus insects birds bears What are some ways that the organisms in this community interact with each other? What is an ecosystem? Slide 12 / 93 Factors Abiotic factors are physical, nonliving factors that shape an ecosystem. What living factors do you see in this ecosystem? What nonliving factors do you see in this ecosystem? Temperature Wind Nutrients Sunlight Precipitation Temperature Wind Soil type Nutrient availability Soil

3 Slide 13 / 93 Factors Biotic factors are the living things that make up an ecosystem. Plants Animals Fungi Bacteria Slide 14 / 93 Biome A biome is a set of ecosystems that share similar characteristics. Biomes are very large areas on Earth s surface, with animals and plants adapting to their environment. Biomes are often defined by abiotic factors such as climate, geology, moisture, and soil type. There are many major biomes on Earth, both terrestrial and marine. Do you know the names of these biomes? Slide 15 / 93 Tundra The frozen cold ecosystems found near the northernmost parts of Earth are called tundras. These locations are known for their long, cold winters and their short, cool summers. Slide 16 / 93 Desert Desert biomes are found throughout Earth and are typically hot and dry. The plants and animals in these biomes have learned to adapt to their environment. What abiotic and biotic factors would you find here? What abiotic factor is this area lacking? Slide 17 / 93 Grassland Grassland biomes can be vast, expanding regions, covering millions of square miles, or kilometers. Slide 18 / 93 Tropical Rain Forest Tropical rain forests are found in locations that receive significant amounts of precipitation. These locations are easily recognizable by their abundance of lifeforms. By looking at the picture, what biotic factor is abundant and what biotic factor is limited? What abiotic factor is abundant in this biome?

4 Slide 19 / 93 Deciduous Forest Deciduous forests exist in areas with a moderate amount of precipitation and where temperatures are also generally moderate. These ecosystems typically have long warm summers, and short cool winters. Slide 20 / 93 Coniferous Forest Also known as taiga, coniferous forest ecosystems are found in regions of Earth that experience somewhat long and cold winters, with summer being much shorter. Name two biotic and two abiotic factors that would be found in this biome. Describe one biotic factor and one abiotic factor in this biome that would differ from the deciduous forest biome. Slide 21 / 93 Biosphere Slide 22 / 93 1 Which is not a level of organization in an ecosystem? A Population All of the terrestrial and marine biomes blend into each other on Earth. B Neighborhood C Community D All are levels of organization in an ecosystem The biosphere is the sum of all the ecosystems established on Earth. Slide 23 / 93 2 A chipmunk and a ground squirrel are two different species. This means that they cannot A live in the same area. B interact in any way. C breed. D eat the same food. Slide 24 / 93 3 Which is not true of ecosystems? A Ecosystems only contain living things. B Ecosystems contain both living and non-living things. C Ecosystems are found on both land and in water. D Ecosystems only contain several communities.

5 Slide 25 / 93 4 Which of the following is not an abiotic factor? A rocks B water C soil D All are abiotic factors 5 Which is not a biotic factor? A people B plants C sunlight D All are biotic factors Slide 26 / 93 Slide 27 / 93 Slide 28 / 93 Habitat Ecosystems The term habitat describes the specific area where an organism lives within an ecosystem. A habitat is like an organism's home within an ecosystem. Return to Table of Contents An organism's habitat answers the question "Where do you live?". Slide 29 / 93 Habitat This penguin's habitat is the ice shelves of Antarctica. Slide 30 / 93 Niche An organism's niche is a description of the role it plays in its habitat. A niche includes all aspects of where and how an organism lives including: * the type of food it eats * how it obtains food * where it lives in its environment (tree, nest, hive, etc.) * when and how it reproduces The saguaro cactus's habitat is the desert of the southwestern US.

6 Slide 31 / 93 Niche Slide 32 / 93 6 The Venus flytrap lives in subtropical wetlands where the soil is low in nitrogen and phosphorus. This is a description of the Venus flytrap's An organism's niche answers the question "How do you make a living?". A habitat. B niche. Komodo Dragon Niche Komodo dragons live in the Indonesian Islands. They hunt and ambush invertebrates, birds and mammals. They lay up to 20 eggs at a time in self-dug holes. The eggs incubate for eight months. Komodo dragons take nine years to mature and can live up to 30 years. Slide 33 / 93 7 The Venus flytrap is a carnivorous plant that captures insects and arachnids that crawl on its leaves. Although they produce food via photosynthesis, their prey gives them nutrients that are lacking in their environment. They are perennial plants, meaning that they flower every year. This is a description of the Venus flytrap's A habitat. Slide 34 / 93 Healthy Ecosystem A healthy ecosystem is composed of: Producers Consumers Decomposers B niche. Can you name other organisms found in each group? Slide 35 / 93 Producers Plants are called producers because they make their own food. They do this by using light energy from the sun, carbon dioxide from the air, and water from the soil to produce food. Organisms that cannot make their own food are called consumers. They survive by consuming plants and animals. Slide 36 / 93 Consumers There are three groups of consumers : Herbivores, Omnivores, and Carnivores.

7 Herbivores are animals that get their energy from eating only plants. Slide 37 / 93 Herbivores Slide 38 / 93 Omnivores Omnivores eat both plants and animals. Slide 39 / 93 Carnivores A carnivore is an animal that eats only other animals. Slide 40 / 93 Consumers By Another Name Consumers can also be classified a different way: Primary Secondary Tertiary Quaternary Slide 41 / 93 Primary Consumers Slide 42 / 93 Secondary Consumers A primary consumer is an organism that feeds directly on plants. These are the herbivores. Grasshopper eats the plant. Secondary consumers are consumers that feed on the primary consumers. These are carnivores. Bird eats the grasshopper.

8 Slide 43 / 93 Tertiary Consumers Slide 44 / 93 Quaternary Consumers An animal that feeds on secondary consumers in a food chain. An animal that eats tertiary consumers. These animals are usually the "top of the food chain". Eagle eats the snake. Snake eats the bird. Slide 45 / 93 Decomposers Bacteria and fungi are decomposers. They eat decaying matter (dead plants and animals). By doing this, they break them down and help them decompose. During decomposition, nutrients and minerals are released back into the soil. The nutrient-rich soil helps plants grow. Slide 46 / 93 8 Some animals can be called producers since they are food for other animals. True False Slide 47 / 93 9 Primary consumers A eat plants. B are considered the top of the food chain. C are herbivores. D Both A and C. Slide 48 / Herbivores, omnivores, and carnivores are all A Producers B Consumers C Decomposers D None of the above

9 Slide 49 / Decomposers are important because they make soil nutritious for other organisms. True False Slide 50 / 93 Sustaining an Ecosystem If you are healthy, you will probably live a long life. The same thing applies to ecosystems. A healthy ecosystem can sustain itself and stay intact (or stable) for a long time. Biodiversity refers to the diversity, or variety, of plants and animals and other living things in a particular area or region. Slide 51 / 93 Biodiversity An ecosystem's health is linked to its biodiversity. Slide 52 / 93 Biodiversity & Stability Biodiversity boosts ecosystem productivity. A larger number of plant species means a greater variety of crops. A greater species diversity means an ecosystem can withstand and recover from a variety of disasters. Translation: As diversity increases, so does stability. Click here to watch a video about biodiversity. Slide 53 / Biodiversity means that there are a variety of in an area. A Plants B Animals Slide 54 / If an ecosystem has high biodiversity, it also has stability. A High B Low C Both a and b D None of these answers

10 Slide 55 / 93 Slide 56 / 93 Ecosystem Interactions Ecosystem Interactions Organisms in an ecosystem interact with their surroundings in numerous ways. They can interact with both biotic and abiotic components. Remember this squirrelfish? List a biotic and abiotic interaction of the squirrelfish with its environment. Return to Table of Contents Slide 57 / 93 Ecosystem Interactions One way to illustrate biotic interactions in an ecosystem is through food chains and food webs, which show feeding interactions. Slide 58 / 93 Food Chain Think about the difference between a chain and a web. How do you think this relates to food chains and food webs? A food chain shows one pathway of interactions in an ecosystem. Click here to watch a video about food chains. Slide 59 / 93 Food Web In most communities, feeding relationships are more complex than can be shown in a single food chain and energy flows in more than one direction. A food web is a diagram that shows the complex interactions and feeding relationships between all organisms in an ecosystem. Slide 60 / 93 Ecosystem Interactions By looking at food chains and food webs, we can hypothesize (guess) what will happen to organisms if certain changes occur. If a disease destroys the grasshopper population, the snake population will have nothing to eat and that population will decrease as well. If the grasshopper population is destroyed, what would happen to the grass population?

11 Slide 61 / Food chains follow a single path as animals eat each other. True Slide 62 / Food are connected by many different paths. A webs B chains False Slide 63 / If a disease destroys the dragonfly population, what animal population will not decrease? A Salamander B Trout C Frog D Phytoplankton Slide 64 / Scientists discover that the trout population has become toxic due to pollution in the water. What other population should they monitor for toxicity? A Mayfly B Bald eagle C Dragonfly D Salamander Source: EPA Source: EPA Slide 65 / 93 Slide 66 / 93 Climate and Ecosystems Altering Ecosystems Climate has an important environmental influence on ecosystems. Climate changes and the impacts of climate change affect ecosystems in a variety of ways. Can you think of ways in which climate could affect an ecosystem? Return to Table of Contents

12 Slide 67 / 93 Climate and Ecosystems A warming climate affects the habitats of many species. Warming could force species to migrate to higher latitudes or higher elevations where temperatures are more conducive to their survival. This means a range expansion or reduction for some species. Animals could be forced to move into less friendly habitats. Some species might have nowhere to go if they are already at the northern or upper limit of their habitat. Slide 68 / 93 Climate and Water Ecosystems Climate change also affects water ecosystems. As sea level rises, saltwater mixes with freshwater ecosystems. This may force some key species to relocate or die, thus removing predators or prey that were critical in the existing food chain. The loss of sea ice can ultimately affect the entire food web, from algae and plankton to fish to mammals. Slide 69 / 93 Climate and Water Ecosystems As rivers and streams warm, warmwater fish are expanding into areas previously inhabited by coldwater species. Coldwater fish, including many highly valued trout species, are losing their habitats. As waters warm, the area of feasible, cooler habitats to which species can migrate is reduced. Slide 70 / 93 Climate and Biodiversity As species die off or are forced to find new habitats, how does this affect an ecosystem's biodiversity? Lowers the biodiversity As biodiversity is affected by climate change, how does this affect an ecosystem's stability? Decreases its stability Slide 71 / 93 Slide 72 / Climate change could affect the migration habits of birds. True False 19 Climate change causes which of the following? A Certain species die B The food chain is altered C Cold water fish lose their habitat D All are true

13 Slide 73 / 93 Unbalanced Ecosystems We have learned that a healthy ecosystem is sustainable through biodiversity. All of the species in an ecosystem have a role to play, and their interactions have to remain balanced. What happens when that balance is disturbed? Slide 74 / 93 Unbalanced Ecosystems Throughout the history of Earth, the delicate balance found within ecosystems has been disrupted many times by natural disasters such as volcano eruptions, floods, and storms. Coral Bleaching Healthy Coral How could a flood affect a forest ecosystem? When any aspect of the coral reef ecosystem is disturbed (such as increased water temp), corals undergo coral bleaching which kills the corals and affects all other species that rely on the corals. Slide 75 / 93 Humans and Ecosystems Humans have been interacting with ecosystems and changing them for as long as human life has existed on Earth. For years these changes have been gradual. Slide 76 / 93 Humans and Ecosystems Humans affect ecosystems in several ways, such as: But the scale, speed, and degree of change now occurring threatens the survival and integrity of many ecosystems Urbanization Deforestation Click here to watch a video about humans and biodiversity. Slide 77 / 93 Humans and Ecosystems These catastrophic changes are easy to see. However, gradual changes such as: the introduction of exotic species, and the elimination of pests and predators, may go unnoticed but can also destroy and ecosystem. How could the introduction of a species destroy an ecosystem? Air pollution Oil Spills For each example, list two impacts on local ecosystems. Consider what happens when a new plant or animal is introduced into an ecosystem where it previously did not exist. The new organism competes with the natural organisms from that location for available resources. Slide 78 / 93 Humans and Ecosystems Kudzu is a Japanese vine that was brought to the US for the 1876 Centennial Exposition in Philadelphia. It grows quickly and covers existing vegetation, leading to death by lack of sunlight.

14 Slide 79 / 93 Case Study: The American Alligator Slide 80 / 93 Case Study: The American Alligator The American alligator was once thought of as an annoying pest. They showed up in people's pools, golf courses, and ate game fish that people liked to catch. So the American Alligator was hunted without limit until it became an endangered species. This caused an unlikely result. As the alligators disappeared, so did all the game fish. How could the disappearance of the alligator cause fish populations to decrease? Gar Alligator Game fish Examine this partial food web and try the question again: How could the disappearance of the alligator cause fish populations to decrease? Slide 81 / 93 Case Study: The American Alligator The alligator's favorite food was a large fish called a gar. With no alligators to hunt them, the gar population exploded. Slide 82 / 93 Case Study: The Sea Otter Sea otters live in the kelp forest ecosystem. Can you guess what gar like to eat? With no alligators to keep their numbers down, the gar started gobbling up all the fish! The alligator was put on the endangered species list in 1967 and protected from hunting. Giant kelp are large seaweed that can grow 90 m (300 ft) in one year! They are important producers in the ecosystem and they offer protection to many species, including an important role as fish nurseries. Slide 83 / 93 Case Study: The Sea Otter In the 18th century, on the coast of California, the sea otter was hunted for its beautiful fur. It was also killed by fisherman who thought they were eating too many of the fish that they wanted to catch. The sea otters were hunted almost to extinction! Slide 84 / 93 Case Study: The Sea Otter Without the sea otter, fishermen began to see changes in the ecosystem. Study this food web and determine some ways that the loss of the sea otter may affect the kelp forest ecosystem. These sea otters are holding hands while sleeping. Source:

15 Slide 85 / 93 Case Study: The Sea Otter Slide 86 / 93 Case Study: The Shark Without sea otters the sea urchin population grew. Sea urchins eat kelp. With so many more sea urchins, they ate up all the kelp beds. Source: Sharks play a very important role in the oceans in a way that an average fish does not. Sharks are at the top of the food chain in virtually every part of every ocean. In that role, they keep populations of other fish healthy and in proper proportion for their ecosystem. With the otters gone and the sea urchins numbers growing quickly, the kelp beds began to disappear. Then the fish, with no safe place to spawn, began to disappear. In just a few years, the fishermen noticed that the fish were suddenly gone. Slide 87 / 93 Case Study: The Shark Slide 88 / 93 Case Study: The Shark Sharks prey on weak, old fish. Can you think of three ways that this would help to keep the ecosystem in check? Keeps the fish population healthier. Prevents the spread of disease. Strengthens the gene pool by removing weak individuals.. Sharks regulate the behavior of prey species, and prevent them from overgrazing vital habitats. Scientists in Hawaii found that tiger sharks had a positive impact on the health of sea grass beds. Turtles, which are the tiger sharks prey, graze on sea grass. What do you think the scientists found when tiger sharks were removed from the area? The turtles ate all the best quality, most nutritious sea grass and these habitats would be destroyed. Slide 89 / 93 Case Study: The Shark Sharks are essential for healthy marine ecosystems. Unfortunately, sharks are being killed for their fins to be cooked in shark fin soup, a food that has assumed cultural value but is not important for human survival or health. Sharks have survived for 450 million years, but may be gone within the next decades. Slide 90 / Suppose that a toxic phytoplankton bloom occurs in the Chesapeake Bay. Of the following organisms, which would be least affected by this? A Wading birds B Tundra Swan C Geese D Benthic Invertebrates Our growing demand for shark fin soup has increased the slaughter of sharks to such a great extent that many shark species are already nearing extinction.

16 Slide 91 / If a parasite decimated the osprey population, which other population would experience a population decrease? A Small planktivorous fish B Large piscivorous fish C Bald eagle D Phytoplankton Slide 92 / A species of bird is introduced into the ecosystem from Asia. This bird is able to outcompete all other birds for both small and large fish. Which of the following is not a result of this invasion? A Gull populations would decrease. B Zooplankton populations would decrease. C Phytoplankton poulations would increase. D Sea duck populations would decrease. Slide 93 / 93