You will take part in a simulation that studies the effect that biotic factors and abiotic factors have on a specific ecosystem.
After completing this tutorial, you will be able to complete the following:
An ecosystem is a natural unit consisting of all the plants and animals in a given area that function together as a whole. In a given ecosystem, there are primarily two parts that make up this habitat-abiotic and biotic factors. Abiotic factors are the nonliving chemical and physical components found within the ecosystem and include sunlight and water. Biotic factors are conditions or materials produced by living organisms that affect the ecosystem. Even a minor change in these factors can upset the balance and even endanger an entire species, perhaps even threaten extinction.
Every organism in an ecosystem needs to obtain energy in order to live. That is why the energy flow from a producer to a consumer is essential for balance within the ecosystem. Organisms can be either producers or consumers in terms of the flow of energy through an ecosystem. Most producers utilize energy from the Sun as they make sugars in the process of photosynthesis, though some bacteria living around deep sea vents gather energy from the chemicals released by the vents, while bacteria living deep underground can collect energy from inorganic sources. Examples of producers include green plants and algae. Primary consumers use producer organisms as food. These consumers are known as herbivores because they only eat plants. Examples of primary consumers include rabbits, sheep, deer, and cattle. Secondary consumers eat primary consumers as their food source. These meat-eating animals are known as carnivores. Examples of secondary consumers include eagles, tigers, and sharks. Secondary consumers also include omnivores. Humans are an example of this type of consumer because we eat both animals and plants. It is important to note that although this Activity Object discusses only producers and primary and secondary consumers, higher level consumers exist. Using the food web below as an example, you can see that the leopard seal and smaller-toothed whale are consumers at a higher than secondary level. A food chain depicts the path of food from the producer to the final consumer. A typical food chain is as follows:
Note that a food chain usually lists the producer on the left (or at the bottom) to the final consumer on the right (or at the top) and arrows point to the organisms that are doing the consuming or eating. Thus the arrows represent the flow of energy through the ecosystem.
In the real world, an ecosystem is much more complicated than a simple food chain, however, as many organisms do not specialize in their diets and eat more than one type of food, and many organisms are eaten by more than one kind of consumer. A food web is a series of interrelated food chains and provides a more accurate depiction of which organisms eat which organisms. A typical food web is as follows:
Energy flows through an ecosystem in one direction: from producer to primary consumer to secondary consumer to higher consumers. A biomass pyramid provides a picture of the feeding and nergy relationships within a food web and the direction of the flow of energy. The pyramid shows that much of the energy is lost when one organism consumes another. In fact, as the energy is transferred from one organism to the next, about 90% of the energy is lost as it goes into the environment in the form of heat energy. The result is that animals at the top of pyramid need a wider biomass base below them to meet their energy needs. Pictured below is a biomass pyramid:
|Approximate Time||35 Minutes|
|Pre-requisite Concepts||Students should have a basic understanding of ecosystems, & graphs.|
|Type of Tutorial||Concept Development|
|Key Vocabulary||abiotic, bald eagle, biotic|