Ecosystems

What is an ecosystem? An ecosystem is made up of all the living and the nonliving things in an area and how those living and nonliving things interact with each other. Ecosystems come in a variety of sizes. They can be as small as a puddle or as large as a continent. Ecosystems are ever-changing and interdependent.

So what are living and nonliving things? Ecosystems are made up of both living and nonliving factors. Living factors are called biotic factors and include animals, plants, fungi, protists and bacteria. Nonliving factors are called abiotic factors. Abiotic factors are water, minerals, sunlight, air, climate, and soil.

So what do biotic and abiotic factors mean to an ecosystem? Biotic and abiotic factors define what an ecosystem will look like, feel like, and what kinds of organisms can live there. Organisms rely on the factors for survival. Light, temperature, water, soil, space for shelter, reproduction, food sources will all determine what kinds of organisms can live in an ecosystem. All organisms rely on these factors for survival.

We all gotta eat. It’s a fact of life that all living things need energy to survive. Some organisms eat plants to obtain the energy their bodies need to survive. These organisms are called herbivores. Search on the internet and find twenty types of herbivores. Some living things hunt other living things to survive. These creatures are called carnivores. Search on the internet and find twenty types of carnivores. Some eat both plants and other animals and are called omnivores. Search on the internet and find twenty types of omnivores. Some living things feed off the remains of dead plants and animals. These are called scavengers. Find twenty types of plant or animal scavengers on the internet. Turn the four lists in to your drawer.

Producers, Consumers, and Decomposers Producers are organisms such as plants that convert the sun’s energy to supply the fuel the organism needs to survive. Producers convert the energy from the sun to energy for themselves through photosynthesis. Consumers are organisms that eat plants and/or other animals for survival. Decomposers are organisms that break down dead plants and animals. These organisms cycle carbon from organic matter back into the soil. This makes the soil more have more nutrients for the producers.

Producers, Consumers, Decomposers Game Go to http://sciencebitz.com/?page_id=1202 and read about producers, consumers and decomposers. Take notes in your notebook. Go to http://www.sheppardsoftware.com/content/animals/kidscorner/games/producersconsumersgame.htm Play the game a few times until you get them all correct.

So, how do these producers, consumers, and decomposers work together? Producers, consumers and decomposers work rely on each other for survival. They form a chain which links them together. If one part of the chain is broken, the whole system is interrupted. We call this system a food chain and it is made up of producers, consumers and decomposers – the abiotic factors in an environment.

How does the food chain actually work? A food chain is the path of energy in food from one organism to another. The producers (mostly plants) grow and become food for the consumers. The consumers eat the producers and some consumers eat other consumers. The decomposers break down dead matter (plant and animal) and return nutrients to the soil which helps the producers grow. Those worms in your yard have a very important job! All food can be traced back to plants! If one part of this chain is broken, the whole chain is disrupted.

Food Webs A food web is overlapping food chains. Competition for food causes food chains to overlap. It shows how one population can be part of more than one food chain and how each population in a community relates to all the other populations.

It’s always changing Remember that ecosystems are always changing. Some changes are good for some organisms and bad for other organisms. When physical factors (light, temperature, water, soil, shelter space, food source) changes some organisms survive, others move to new locations, others move in to the transformed (changed) environment, and some die.

Think about it. On a sheet of paper, describe what would happen if there was a drought and there was a decrease in the population of the producers. Be sure to explain what would happen to both the consumers and the decomposers. If plants or prey (hunted animals) become scarce, their predators may move to a new area. What will happen to the ecosystem the predators move into?

Food Chain Game Go to http://www.ecokids.ca/pub/eco_info/topics/frogs/chain_reaction/index.cfm and play the game. Take notes of what you learn about food chains in your notebook.

Habitat Game In pairs, you will play the Habitat Game.

Think about it. On a sheet of paper, answer the following questions. Put these organisms in order in a food chain: frog, snake, algae, snail. What type of organism (producer, consumer, or decomposer) are most plants? What type of organism cycles carbon from organic matter back into the soil? In a forest ecosystem, a food chain might look like this. Green plants – rabbits – coyotes – mountain lions If the green plants are destroyed in a forest fire, what would be the effect on the organisms in the food chain? A grassland food chain might look like this: grass – mouse – snake – hawk If all the snakes are removed from the ecosystem, how will this affect the populations of hawks and mice? A tropical rainforest supports a wide variety of plants. What does the ecosystem gain by having a wide variety of producers?

Two Major Types There are two major types of ecosystems. Terrestrial: Terrestrial ecosystems are land based ecosystems. Aquatic: Aquatic ecosystems are water based ecosystems.

What are the different types of ecosystems? Your world is divided into 6 major kinds of terrestrial ecosystems. These 6 kinds of ecosystems are called biomes. Desert Tundra Grassland Deciduous Forest Taiga Tropical Rain Forest

Desert: Land of Little Rain

Where are deserts located and how much rain do they get? Of all the biomes in the world, the desert biome has the driest climate. Desert biomes are found at middle latitudes. The largest deserts are found in North Africa, southwestern North America, the Middle East, and Australia. Rainfall in the desert often totals only a few inches a year and in some regions, there is no rainfall at all!

What is desert soil like? Desert soils are often salty because what little rain that does fall is immediately evaporated, leaving salt and other minerals behind.

Desert Plants Since rainfall is so scarce, plants in the desert are drought-tolerant. This means they can survive without water for long periods of time. Desert plants usually have waxy leaves, large root systems and water storage systems. These adaptations help desert plants cope with not having much water. Desert plants include cacti, yucca, bunch grass, shrubs, and very few trees.

Desert Plants

Desert Animals The animals that live in the desert have special adaptations too. These adaptations help them survive with little or no readily available water. Many desert animals are light-colored. The desert animals use this light-coloring to help camouflage them from predators. Desert animals are also more active at night and around dawn and dusk. This allows them to escape the scorching heat during the day. During the day, desert animals often lay in burrows or under rocks. Desert animals include rodents, snakes, lizards, tortoises, insects, and some birds. Camels, gazelles, antelope, small foxes, gerbils, and kangaroo also live in the desert.

Desert Animals

Desert Animals

Tundra: The Frozen Praire

Where are tundras located and what is the climate like? Tundra biomes are found in the high northern latitudes of the earth. They are found only in the Antartic. A tundra biome has very cold, harsh, long winters. Temperatures here often reach about -50 degrees F! The summer in a tundra biome is very short and the temperatures are cool.

What is the soil like in a tundra biome? Their soil is poor in nutrients. The top few inches of soil are always frozen. This is called permafrost.

Tundra Plants Because of the very cold conditions, it is impossible for trees to grow in the tundra. Plants in the tundra are grasses, wildflowers, mosses, and small shrubs.

Tundra Plants

Tundra Animals Even though it is so cold in the tundra, many animals have adaptations to help them survive in the cold climate. Animals in the tundra usually have very thick fur to help keep them warm. Animals where the land is covered with ice are often white. This helps them to blend in with their surroundings so they can hunt easier and hide from predators. Animals in the tundra include: caribou, artic hare, mink, weasel, wolf, brown bear, reindeer, hawks, polar bear, walrus, arctic fox.

Tundra Animals

Tundra Animals