Ecosystem

Objectives :

• To identify components in ecosystem and to explain in that sun is the source of energy in the biological system
• To draw the diagram of food chain and food web from an ecosystem

When you study interactions in an ecosystem you also learn ecology

• Ecology is a branch of biology that studies interactions among organisms and environments in ecosystems

Unit of organisms

1. Individual is a single organisms

ex., a rabbit, a cow, an eagle.

2. Population is a group of individuals of species that live in the same area at the same time or all individuals of the same kind that occupy a certain region

ex., rabbit population, cow population, eagle population.

3. Community is a group of population or

all of the population which occupy the same region

4. Ecosystem is interaction between living things with their environment or a complex two directional relationship between organisms and their surrounding, whether biotic or abiotic.

5. Biosphere is a collection of ecosystems found on earth surface.

Ecosystems are distinguished into three as follow :

1. Natural Ecosystem, that is an ecosystem which is formed naturally without human intervention.

ex., desert ecosystem, tropical rain forest ecosystem, oceans ecosystem, freshwater ecosystem (rivers, lakes, and ponds), etc.

2. Artificial Ecosystem, that is an ecosystem which is made on purpose by human.

ex., a pool ecosystem, rice field ecosystem, park ecosystem, artificial rubber forest ecosystem, etc.

3. Succession ecosystem, that is an ecosystem which is the product of environment succession which is preceded by damage.

ex., a region has experienced volcano which gradually form a new ecosystem.

Constituent Components of Ecosystem

1. Biotic Components

1. Autotrophic organisms / Producers

is the organisms that can make their own food or organisms which are able to produce organic material through photosynthesis process. Ex., green plants.

1. Heterotrophic organisms / Consumers

is organisms which cannot produce their own food substance. Ex., all animals and plants which have no chlorophyll.

Types of Heterotrophic organisms:

a. Herbivores, the organisms which consume plants or producers.

b. Carnivores, the organisms that eat animals.

c. Omnivores, the organisms that eat both plants and animals.

2. . Decomposers

are the biotic component that function to decompose organic matter coming from dead organisms or the discharge of digestion residue. Ex., decomposing bacteria and fungi.

2. Abiotic Components

Abiotic parts of an environment include such things as soil, water, air, temperature, sunlight, and climate.

Habitat and Niche

• Habitat is the area where organisms live in. Ex., the habitat of fish in water, the elephant’s habitat is the forest, the cactus's habitat is the desert.
• Niche is the role of an organisms in ecosystem. Ex., the fish’s niche is eating algae to keep its population

Food Chains

Is the process of eating and being eaten or

the transfer of energy from one organisms to another in an ecosystem.

For example;

Daisy ladybug grouse wolf

Food Webs

Is the interconnection of several different food chains produces a more complex model of feeding relationship.

Or

A series of overlapping food chains.

Ex.;

Energy Pyramids

Are one way to show the relationships of organisms in communities. A pyramid of numbers shows how many individuals an ecosystem can support.

Look at the figure:

A pyramid of numbers would include 175 grass seeds, 40 grasshoppers, 5 woodpeckers, and 1 Hawk. Pyramids of numbers may look different from energy pyramids. What would a pyramid of numbers look like if it included one tree and one thousand insect?

Interaction Patterns (Relationships among organisms in community)

1. Competition, when two or more species compete resources
2. Predation, is another interaction in a community in which one organism becomes a predator and see the other as prey. (Predator is animal that hunt, kill, and eat other animals. Prey are animals that are killed by predators.)
3. Symbiosis, the interaction that occurs between two different species that live together in an ecosystem.

symbiosis classified become 3 group ;

a. Mutualism

b. Commensalisms

c. Parasitism