Basic Ecology

Ecology, what does it mean?

It is the study of interrelationships and interactions between the living (biotic) organisms and their non-living (abiotic) environment and the study of the processes that take place during such interactions.

An Ecosystem: 

It is a system of living organisms that interact with each other and their surrounding environment.

Levels of organisation in Ecology:

• Individual (single organism of a particular species)
• Population (interbreeding group of organisms of the same species)
• Community (all populations found within a given area)
• Ecosystem (living and non-living components)
• Biome (group of communities with own climate, vegetation and animal life, covering a large area)
• Biosphere (system including all life on earth and the physical environment)

What is a Food chain?

It is the description of the way energy flows through the ecosystem. Energy is transferred from plants through a series of organims by eating and being eaten.

What is a Food web?

It is the number of food chains liked and interwoven into a complex food web due to some species being eaten by a number of different predators and not only one line of energy flow.

A food chain usually consists of Producers, Consumers, Decomposers.

Producers: plants that are able to synthesise or manufacture their own food through the process of phosynthesis (autotrophs). The energy from the sunlight is converted into a form of chemical energy that can be used.

Consumers: organisms that are not able to produce or manufacture their own food and thus relay on other organisms for their nutritional requirements.

1. Primary consumers: animals that feed on plants (kudu)
2. Secondary consumers: animals that feed on other animals (lion)
3. Tertiary consumers: animals that feed on other meat-eating animals (hyena)

Decomposers: Organisms that are able to break down existing organic material (dead wood, dead animal tissues...) (Heterotrophs) ex: bacteria, sacrophytic fungi, insectes: termites, beetles...

Here is the Nutrient Cycle (Mineral recycling):

And here is a Trophic Pyramid: