ECOLOGY

WHAT IS ECOLOGY?‘

Oikos’ is the root word for ecology meaning home or dwelling place. Ecology is defined as the study of the inter-relationship between living organisms and their non-living environment. Biologist who study organisms and their environment are called ecologists. the study of a single species of organism is called autecology and the study of different species is called synecology.

ECOLOGICAL TERMS

Some terms are indispensable when studying ecology. Some of these terms include:

      BIOSPHERE / UNIVERSE

Both living and nonliving things constitute the universe or nature. The part of the universe where life exist is called biosphere.

Biosphere is divided into

1.       Lithosphere – the part of the biosphere covered with earth or rock. Make about 30% of the universe.

2.       Hydrosphere –part that is covered with water and include ocean, seas, rivers, ponds etc. Covers about 70% of the universe.

3.       Atmosphere -part above the lithosphere filled with gases. Made up of 78% nitrogen, 21% oxygen, 0.03% co2 and 0.97% rare gases and water vapour.

The biosphere is also called the ecosphere.

Environment: environment is said to be the total surrounding of the organism. In the real sense environment constitute all the external and internal factors which affect the survival of an organism. It includes the physical surrounding of an organism the nonliving factor and living things which affects an organism. For example, teachers, birds, mosquitoes, sunlight, rain fall, school premises are all the environment.

Habitat the actual or physical living place of an organism is its habitat. There are basically two types of habitat. Viz

·         aquatic habitat

·         terrestrial habitat

Aquatic habitat comprises of all the salt water, fresh water and brackish water habitats.

Terrestrial habitat includes all the living place on land on tress and underground.

Niche: the functional roles and specific place where an organism occupy in any habitat is called niche.

A caterpillar in the garden it niches as follows

·         It lives on the undersurface of the leaves

·         It destroys the leaves used for photosynthesis.

Population : this is the number of organism of the same specie living in a particular area at any given time.

Community : this is a population of different specie living together in an area at a time.

Biome : a biome is defined as the largest ecology community of organisms. It is a number of communities dwelling together and intereacting together for mutual survival. Biomes in nigeria include

    forest

    savannah

   open seas

   coast. Etc.

THE ECOSYSTEM

The ecosystem is a self-supporting unit made  up of living and nonliving things. It is the interaction of living thing and  nonliving things  in an environment. Two components called the

1.       Biotics components

2.       Abiotic components

Biotic components include all the living factors and all the factors that relate to living things. They are

v  Producers – decomposers

v  Consumers

Abiotic factors component are subdivided into

v  Climatic factors

v  Edaphic factors

v  Topographic factors

v  Chemical / inorganic factors

v  Hazard factors e.g. fire, storm, wind, dust etc.

Abiotic factors are generally referred to as ecological factors or habitat factors.

Biotic factors may be broken down to it include

Competition, parasites, predators, pathogens, migration, pest, disease, dispersion of seed, mortality and natality.

WORKSHEET

Evaluation: now you have read through this note, do the following exercise

1.       Define ecology

2.       Mention 2 branches of ecology

3.       Complete the extract below using appropriate terms from ecology

The part of the universe where life exists is the _____________________. Part of which is called the lithosphere made of ____________ and part made up of gases called the __________________. A part of this universe is filled with water and called the ______________. The total external and internal factors affecting a Joey in Australia is its __________________. Some habitats are made of water(                                   ) while some compose of land (                                    ). The role and specific place of an organism in its habitat is its_______________. When populations combine, they give a __________________ and the largest eco community is called __________________