Objective 2 (7.12) Science concepts. The student knows that there is a relationship between organisms and the environment. The student is expected to (B) observe and describe how organisms including producers, consumers, and decomposers live together in an environment and use existing resources;

8.11a Describe prod/cons; pred/prey; parasite/host in marine, freshwater, and terrestrial ecosystems Investigate biotic and abiotic factors such as light; water; temperature, soil Explore short and long term changes in subsequent populations Recognize human dependence on ocean systems and how humans modify the systems

Parts of an Ecosystem Parts and Pieces What are the major parts of an ecosystem? An ecosystem includes soil, air, heat and light from the sun, water, and living organisms.

All of the external conditions that affect an organism ENVIRONMENT All of the external conditions that affect an organism Biotic factors are the living parts of the environment Abiotic factors are the nonliving parts of the environment

Abiotic Parts Give Me a Little Air Getting Down and Dirty The air provides oxygen and carbon dioxide for the plants and animals.  Without the complex interactions and elements in the atmosphere, there would be no life at all Getting Down and Dirty Soil is a critical part of an ecosystem. It provides important nutrients for the plants in an ecosystem. Soil absorbs and holds water for plants and animals to use.

Abiotic Parts Getting Some Sun The heat and light from the sun are critical parts of an ecosystem. The sun's heat helps water evaporate and return to the atmosphere. The heat also keeps plants and animals warm.  Without light from the sun there would be no photosynthesis and plants wouldn't have the energy they need to make food.  Water Everywhere Without water there would be no life.  Water is a large percentage of the cells that make up all living organisms.  Without water all life would die. Water is also used by plants to carry and distribute the nutrients they need to survive

What are the biotic and abiotic factors in this picture? http://www.thegardenhelper.com/102902.JPG

Biotic parts of the Ecosystem As I Live and Breathe Ecosystems have lots of different living organisms that interact with each other.  Living Systems can be divided into three categories: producers, consumers, and decomposers. 

Living- Ecosystems Decomposers are plants Consumers and animals that break down (by consuming) dead plants and animals into organic materials that go back into the soil. Which is where we started! Producers are the green plants.  They make (produce) their own food. Consumers are animals that get their energy from producers or from organisms that eat producers. There are three types of consumers:  herbivores eat plants carnivores eat herbivores and sometimes other carnivores, omnivores eat plants and other animals

BIOTIC ABIOTIC Cows Grass Trees Shrubs Others unseen Air Water Soil, rocks Light Temperature

ENERGY FLOW AMONG ORGANISMS Everything you do requires energy. How do you get the energy that you need?

All living things get energy from their food to carry out life processes. Plants make their food. Animals eat their food.

A food chain shows how each living thing gets its food A food chain shows how each living thing gets its food. Plants make food using energy from the sun. Some animals eat plants and some animals eat other animals. Each link in a chain is food for the next link. Arrows indicate the direction of energy flow.

Food Chain vs Food Web FOOD CHAINS FOLLOW A SINGLE PATH AS ANIMALS EAT EACH OTHER. FOOD WEBS SHOW HOW MANY ANIMALS ARE INTERCONNECTED BY DIFFERENT PATHS. FOOD WEBS show how plants and animals are related in many ways to help them all survive.

sagebrush pronghorn coyote http://www.wsu.edu:8080/~wsherb/edpages/raingrass/images/ginkgoparksageonridge.jpg pronghorn http://www.gpnc.org/pronghor.htm coyote http://www.desertusa.com/june96/du_cycot.html So: Coyote eats pronghorn, which ate the sagebrush

Plants are called producers because they are able to use the energy from the sun to produce the food they need using carbon dioxide and water.

Animals cannot make their own food so they must eat (or consume) plants and/or other animals. They are called consumers. There are three groups of consumers.

HERBIVORES Animals that eat ONLY PLANTS (herbs) are called herbivores. http://www.gpnc.org/pronghor.htm

CARNIVORES Animals that eat OTHER ANIMALS are called carnivores. www.desertusa.com/ www.desertusa.com/ http://www.orcahome.de/orcafact.htm

OMNIVORES Animals that eat BOTH animals and plants are called omnivores. Raccoon American bear http://animaltrial.com/animals/bearpicturesfolder/blackbearpictures/blackbearwalking.html http://www.loomcom.com/raccoons/gallery/jpegs/raccoon1.jpg

OMNIVORES Copyright © Tim McCabe, NRCS

Some animals eat dead animals or carrion. They are called scavengers Some animals eat dead animals or carrion. They are called scavengers. They help break down or reduce organic material into smaller pieces. roach vulture hyena http://pested.unl.edu/amerroa.jpg http://www.factmonster.com/ipka/A0768543.html http://www.mbr-pwrc.usgs.gov

DECOMPOSERS Organisms (bacteria and fungi) which feed on decaying matter. Decomposers and scavengers break down dead plants and animals. They also break down the waste (feces) of other organisms. Decomposers are very important for any ecosystem. If they weren't in the ecosystem, the plants would not get essential nutrients, and dead matter and waste would pile up.

DECOMPOSERS Fungi Bacteria http://www.qrg.northwestern.edu/projects/marssim/simhtml/info/whats-a-decomposer.html

http://www.arcytech.org/java/population/facts_foodchain.html

THINK ABOUT IT! What would happen to a forest ecosystem if the bacteria and fungi on the forest ground all died of disease?

A herbivore is called a primary, or first order consumer because it eats the producers. A carnivore that eats herbivores is a secondary, or second order consumer. Some predators are called tertiary, or third order consumers. These animals usually have no predators.

Photosynthesis Producer Primary Consumer Secondary consumer Tertiary consumer Decomposer

Why are there more herbivores than carnivores? In a food chain, energy is passed from one link to the next. When a herbivore eats, only a fraction of the energy that it gets from the plant food becomes new body mass; the rest of the energy is lost as waste or converted to heat (by the herbivore).

Likewise, when a carnivore eats another animal, only a portion of the energy from the animal food is stored in its tissues. In other words, organisms along a food chain pass on much less energy (in the form of body mass) than they receive.

ENERGY PYRAMID Because a large amount of energy is lost at each link, the further along the food chain you go, the less energy is available. We use the energy pyramid as a model to show decreasing available energy at each level in the pyramid.

.1% 1% 10% 100%

0.1% energy 1% energy 10% energy 100% energy

FOOD WEBS Most organisms are part of more than one food chain. Many animals eat more than one kind of food in order to meet their food and energy requirements. These interconnected food chains form a food web.

Food Webs Show relationships Within the entire Ecosystem – how the Ecosystem is INTER-CONNECTED

1. If the grasshopper population is removed, who gets hurt the most? 2. List the secondary consumers 3. If there is an increase in grasses, what will the result be?

MARINE FOOD WEB http://www.gould.edu.au/foodwebs/kids_web.htm

Look at these pictures Discuss what you see with Your table mates

YOUR TURN! 1. In this food web, the bacteria probably function as A producers B herbivores C decomposers D carnivores

The correct answer is “C”, decomposers The correct answer is “C”, decomposers. Bacteria are decomposers that break down the remains of dead plant and animal material. A. Incorrect. Bacteria in this food web are not producers. B. Incorrect. Bacteria are decomposers of both plant and animal material. D. Incorrect. Bacteria are decomposers of both plant and animal material.

2. Energy used by producers in this grassland food web is provided by A. sunlight B. water C. oxygen D. carbon dioxide

Correct. Producers use energy from the sun to produce food in the form of sugar. Incorrect. Water is a raw material (reactant) necessary for producing food, it is NOT energy. Incorrect. Oxygen is a product of photosynthesis, it is NOT energy. Incorrect. Carbon Dioxide is also a reactant necessary for photosynthesis, it is NOT energy.

3. Which of the following is the correct flow of energy through an ecosystem? Producers sun decomposers consumers Sun consumers decomposers producers Sun producers consumers decomposers Producers consumers decomposers sun

The correct answer is “C”. The sun provides energy that producers use to make food. Consumers eat plants or other consumers to get energy. Plants and animals die. Decomposers get energy by feeding on decaying plant and animal matter.

A suburban community has a colony of bats that feeds mainly on the mosquitoes that live in the ecosystem. Because of the danger of West Nile Virus being spread by mosquitoes, the community launched a spraying program to kill the mosquitoes. What effect will this most likely have on the bat population? A. The bat population will not be affected. B. The bat population will decrease because its food supply will decrease. C. The bat population will increase because it will find other things to eat. D. The bat population will be killed off by the mosquito spray.

The correct answer is “B” The correct answer is “B”. The bat population is likely to decrease because of a decrease in the food supply. A Incorrect. The competition for food will be too great for the population to not be affected. C Incorrect. The bat population is unlikely to find another food source to cause its population to increase. D Incorrect. The mosquito spray is unlikely to kill off the bats.

Extinction is the death of an entire species. Examples of extinct animals are: Dinosaurs Extinct: Cretaceous Period Dodo Extinct 1681

Populations may be reduced in number, but rather than die out, Very often however, the consequences from environmental change is not so drastic as extinction. panda Loggerhead turtle Grey wolf Mexican Spotted owl Humpback whale Populations may be reduced in number, but rather than die out, they may become endangered or threatened.

Threatened species are likely to become endangered in the foreseeable future. Endangered species are in danger of becoming extinct. Until recent sightings in Arkansas during 2004-2005, the ivory-billed woodpecker was believed to be extinct. It is now classified as endangered.

Human caused negative effects Strip Mining- humans use bull dozers to strip the land of all living things in order to get to the minerals beneath Clearing forests- we use the wood to build or we clear the land to build Over harvesting – fishing or hunting to extinction or near-extinction (animals and humans both do this)

Human activity does not always produce a negative environmental impact. Pressure from special interest groups have helped with the creation of laws and practices that are designed to help reverse the negative impact on the environment due to human activity.