Ecosystems Chapter 3 Biosphere Entire area of Earth

Ecosystems Chapter 3

Biosphere • Entire area of Earth in which life exists • Includes atmosphere • Made up of smaller ecosystems – All living organisms in an area – Non-living parts, such as water and rocks – Healthy ecosystem is in balance – Always changing

Ecosystem • Community of living organisms and nonliving components, acting as a system

Environment • Environment: The ecosystem surrounding an organism • All the living organisms make up a community (fish and squirrel) • All the organisms of one species belong to a population (only squirrels) • Each population lives in a habitat • Each has a role and resources, called a niche

Biosphere What about you? ? Ecosystem Environment Community Population Habitat Niche

Energy Cycles Starts with the Sun!!!

Food chain • Path energy follows as it moves through the community • Sun>Plants (Producers)>Herbivores (Consumers)>Omnivores (Consumers)>Carnivores (Consumers) • Primary, Secondary, Tertiary, Quaternary Consumers • Where are you on the food chain?

Food Web • Carnivores are at the top, but when it dies, decomposers break apart the body and the nutrients return to the soil • All the food chains in a community form a food web • A change in one part can affect all the other parts • For example, what would happen if all the insects disappeared?

The circle of life You Animals Insects Bacteria Plants

Biomes • Large group of ecosystems with similar climates and communities • About six worldwide: – Deserts – Tundras – Grasslands – Tropical Rainforests – Temperate forests – Oceans – PLUS! Freshwater Areas

Tell me about your biome!

Biodiversity • Biodiversity: Wide variety of living things • Under attack from human activities (development, construction, farms, pollution, dams, water use, deforestation) • Some experts call this the Anthropocene Era • Some scientists believe we are causing the 6 th mass extinction

Ecology • Ecology: Study of how organisms interact with one another and the world around them • Producers>Consumers>Decomposers and scavengers – All are important! • For example, predator-prey relationship • Predators hunt and kill their prey • Many organisms are both predator and prey • Can you think of any?

Predators Prey http: //smartgraphs-activities. concord. org/activities/225 -african-lions-modelingpopulations/student_preview

• Do vocab review and skill practice(pg. 93)

3. 2 Carrying Capacity • Every organism and population has a habitat • Habitat can only support a limited number of organisms • Carrying capacity: maximum number of organisms that a habitat can support • Limiting factor: any factor that limit that amount of organisms with an environment • Can you think of any? Food, water, shelter, space

• Each species has a tolerance, or range in which it can survive • For example, humans can only survive temperatures around -60 F to 120 F (depending on clothes, etc) tolerance

Relationships in a habitat • Species compete for limited resources • Competition exists within a species or between species • If the carrying capacity is exceeded, then a population may have to migrate, adapt or die off • Populations move towards equilibrium as a variety of pressures are exerted

The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water, and other necessities available in the environment.

Reindeer on Pribilof Islands

What are our options? Migration, starvation, or adaptation To adapt, you can diversify Diversify: branch out and try new things! For example, sea otters eat sea urchins if they are plentiful. If not, may have to eat something else. • Do vocab review on pg. 100 • •

3. 3 Symbiosis • In an ecosystem, all living things interact with other living things and nonliving things • Ecosystems are complex and always changing • Some species compete with one another for the same resource • Some species are predators and others prey • Some species live and work together in balance, called symbiosis

Symbiosis • interaction between two different organisms living in close physical association, typically to the advantage of both. • a mutually beneficial relationship between different people or groups.

Three Types of Symbiosis • Mutual Symbiosis • Parasitic Symbiosis • Commensal Symbiosis

Mutualism • Also called mutual symbiosis • Win-win situation! Both parties benefit equally

More examples of mutualism • Termites & bacteria: – Termites host bacteria and protists (host is an organism on which another organism lives and feeds on) – Bacteria help the protists and the termites to digest the cellulose in plants (cellulose is the tough outer layer of plant cells; thick fibrous carbohydrate) – More info: http: //science. jrank. org/pages/1335/Cellulose-digestion. html

Mutualism, cont. • Acacia Trees & Ants: Ants live inside thorns that grow at the base of a tree’s leaves. Thorns provide a home for ants, and the ants bite animals to eat a tree’s leaves. Who knew that a tree could use an ant to defend against an elephant? ?

Mutualism, cont. • Oxpeckers, rhinos & zebras: An oxpecker is an Aftican bird that feeds on ticks and other parasites. It hangs out on rhinos and zebras and cleans them off, getting food and cleaning the animals. It also warns them of danger.

http: //www. animalplanet. com/tvshows/animal-planet-presents/videos/top-10 odd-animal-couples-the-giraffes-oxpecker/

Mutualism, cont. • Humans & E. coli: Bacteria are our friends! E. coli lives in our digestive tract. We are the host; the bacteria help us digest food and absorb vitamins. Also helps defend against harmful bacteria and stimulates the immune system to produce antibodies (proteins that fight off and kill harmful microbes)

Parasitic symbiosis • Parasitism: relationship in which the parasite benefits but the host doesn’t • Relationship between two species of plants or animals in which one benefits at the expense of the other, sometimes without killing it.

Two kinds of parasites • Endoparasites: live INSIDE an organism’s body • Ectoparasites: live ON an organism’s skin • Also, an insect could lay an egg on a host. The eggs hatch and devour the host.

Parasitism examples • Ticks: – Ticks are arachnids (tiny invertebrates such as spiders) – Ticks can attach to a host’s skin and suck blood for several days, which allow pathogens, or diseasecausing organisms, to enter the host

Parasitism, cont. • Tapeworms: – Can infect vertebrate and invertebrate species (animals with or without a spinal column) – Can live in liver and digestive tract; attaches with suckers and absorbs food from the host – Can produce 40, 000 unhatched young, or embryos – If others ingest the eggs, they turn into larvae in the new host’s digestive tract – The larvae bore through the intestinal wall and enters the blood and ends up in the muscle – If the cyst, or protective outer covering, is eaten (like if we eat an infected cow), the larvae attach to the new host and become an adult – Symptoms include weight loss, vomiting, headache and seizures

Commensal Symbiosis • Also called commensalism: one species benefits from a host, but the host is unaffected. The host is neither help nor hurt by the relationship.

Commensalism examples • Pseudoscorpian and beetles • Cattle egrets and livestock • Sharks and remoras

3. 4 Disruption • An ecosystem is comprised of both biotic and abiotic factors • Ecologists study the interactions between biotic and abiotic factors in an ecosystem

Disruptions • An ecosystem is always changing, but some changes are larger than others • These are called disruptions, or breaks in normal events • Can be natural or man-made • Examples: fires and flood • Can sometimes be beneficial as well as harmful

Disruptions, cont. • Since the 1700 s, about 40 percent of the specie on Earth have become extinct • Partly due to invasive species, which humans from its natural habitat to a new habitat • Habitat loss leads to loss of biodiversity • Includes agriculture, forestry, mining, urban growth and pollution • Humans have caused the rate of species extinction to increase by 1, 000 times

• Habitat degradation and habitat fragmentation can also be caused by human activity • Habitat destruction is also sadly common: – In the U. S. , more than 85% of forest habitats have been permanently destroyed or logged – More than 75 percent of forests growing along waterways such as streams have been destroyed – In Michigan, 99% of mature oak and beech maple forests are gone – In Oregon, nearly all of the temperate rain forest is gone – 95% of U. S. grasslands have been planted with crops or destroyed – In Southwest deserts, cattle have overgrazed over 90 percent of sagebrush habitats

3. 5 Environmental Issues • The United States Census Bureau estimates that the world population exceeded 7 billion on March 12, 2012

Will we run out? • Natural resources are things in the environment which we need to survive (air, food, water, wood) • Two types: renewable resources and nonrenewable resources – Renewable can be replaced within the average lifetime (trees, crops, animals) – Nonrenewable cannot be replaced easily (minerals, precious metals, oil, topsoil)

Conservation • Reduce, reuse and recycle!

Pollution • • Garbage (landfills, burned, recycle) Hazardous wastes (chemicals) Air pollution (CFC, smog, coal, heavy metals) Water pollution (mines, factories, power plants, sewage, fertilizers, acid rain)

Garbage rates increased by 500 pounds person from 1965 -2005

• Endangered species: when few individuals are left alive; in danger of becoming extinct • Global climate change may result in more extreme weather, unpredictable weather patterns, ocean acidification, melting polar ice caps, droughts, wildfires, hurricanes, sea level rise, etc. http: //www. arkive. org/endangered-species/