Ecosystems

 

Relationships

 

There are two types of relationships shared between organisms in an ecosystem: predator/prey relationships and symbiotic relationships.

A predator prey relationship is simple. A predator organism consumes another organism, its prey. The relationship between producers and consumers is a predator prey relationship.

A symbiotic relationship is more complex than an animal simply consuming another. There are 3 types of symbiotic relationships.

• Mutual relationship – The rarest symbiotic relationship. In this relationship, two

organisms both benefit from their interaction with each other.

• Communal relationship – One organism benefits from another, while the other

organism is neither benefited nor harmed.

• Parasitic Relationship – One organism benefits from another organism, while the

other organism is harmed.

 

(Give Examples of Each relationship).

 

 

 

 

 

Diagrams

 

Members of the community that is an ecosystem can be diagramed many ways. A food chain is a chain of animals and what they eat. At the top of the chain is the organism that is not eaten and at the bottom of the chain is the organism that does not eat anyone.

 

This is an example of a simple food chain:

 

Humans à Cows à Grass

 

A food web is a web that shows the many overlapping food chains within an ecosystem.

 

Here is an example of a food web:

 

http://www.biologycorner.com/worksheets/foodweb.htm

 

A major difference in a food web from is that the arrows do not start at an animal and point to what they eat, but they start at an animal and point to the animal they are eaten by.

An energy web is similar to a food web except that it shows the levels of energy consumed by each level of organism. It may be diagramed in a trophic pyramid. Producers, animals that can convert energy from the sun, are at the bottom. Producers, animals that get energy by eating other animals, are at the top.

 

Here is an example of an energy web:

 

(Energy Web Example)

Environmental Factors and Limiting Factors

 

Environmental Factors

In an ecosystem, there are two types of environmental factors, biotic and abiotic. A biotic factor is an animal or a physical feature of that animal. An abiotic factor is a feature of the environment in which animals live.

For example, biotic factors affecting the transportation of a shark would be its weight and the fins that it possesses. Abiotic factors would be the water it is swimming in and the temperature of that water.

 

(Picture of shark in water)

 

Limiting Factors

Limiting factors affect one thing: the population of an ecosystem. An ecosystem can only handle a certain population, its carry weight?. Limiting factors reduce population so that it grows at a steady rate that the ecosystem can handle. If there are not enough limiting factors, the population will grow at an exponential rate. Pretty soon, the ecosystem will not be able to handle this and a boom and bust cycle will occur. A large portion of the population will die at once.

 

Nutrient Cycles

 

Ecosystems recycle nutrients. Many different organisms all play parts in cycling a single nutrient and also multiple nutrients. The 3 major cycles are carbon dioxide cycle, nitrogen cycle, and water cycle.

 

(Get cycles from book)