Topic: Basic Ecological System
Table Of Contents
- Meaning Of Ecology
- Ecological Concepts
- Components Of An Ecosystem
- Interactions Among The Components Of Ecosystem
Meaning Of Ecology
The word, ecology can simply be defined as the study of plants and animals in relation to their environment. Ecology is derived from a Greek word Oikos which means home or dwelling place. In other words, ecology can be defined as a field of study which deals with the relationship of living organisms with one another and with the environment in which they live. Ecology is often described as environmental biology.
Ecology is divided into two main branched:
1. Autecology: Autecology is concerned with the study of an individual organism or a single species of organism and its environment. For example, the study of a single rat and its environment.
2. Synecology: Synecology is concerned with the study of the inter-relationships between groups of organisms or species of organisms living together in an area. For example, the study of different organisms in a river in relation to their aquatic environment.
There are some important concepts commonly used in the study of ecology which enable one to understand the subject matter. Some of these ecological concepts include:
1. Environment: The environment includes all the factors external and internal, living and non-living factors which affect an organism.
2. Biosphere or Ecosphere: The biosphere or ecosphere is the zone of the earth occupied by living organisms. It is a layer of life which exists on the earth surface.
3. Lithosphere: The lithosphere is the solid portion of the earth. It is the outermost layer or zone of the earth crust. It is made up of rocks and mineral materials, and it also represents 30% of the earth surface.
4. Hydrosphere: Hydrosphere is the liquid or aquatic part of the earth or living world. It covers about 70% of the earth’s crust. Examples of hydrosphere are lake, pools, spring, ocean or sea, ponds, oasis, rivers and streams.
5. Atmosphere: The atmosphere is the gaseous portion of the earth. It is a layer of gases surrounding the earth. Over 99% of the atmosphere lies within 30km of the earth surface.
6. Habitat: Habitat is defined as an area occupied by a biotic community. In other words, habitat is any environment in which an organism lives naturally. It is the natural home of an organism. For example, the habitat of the fish is water.
7. Biotic Community Or Biome: A biotic community is any naturally occuring group of different organisms living together and interacting in the same environment. A biome is the largest community of organisms, e.g. rain forest, Guinea savanna, etc.
8. Ecological Niche: Ecological niche refers to the specific portion of a habitat which is occupied by a particular species or organism. It is the functional position of an organism within the community.
9. Population: Population is defined as the total number of organisms of the same species living together in a given area. For example, the total number of Tilapia fish in a pond constitutes the population of Tilapia fish in that habitat.
10. Ecosystem: An ecosystem refers to a community of plants and animals functioning together with their non-living environment. In other words, ecosystem consists of the living factors (plants and animals) interacting with the non-living factors in an environment.
Components Of An Ecosystem
The ecosystem is made up of two main components. These are the biotic (living) components and the abiotic (non-living) components.
1. Biotic Components: The biotic components include the living things (plants and animals) which can be grouped into producers, consumers and decomposers.
i. Producers: Producers are autotrophs (Green plants and some micro-organisms) which can manufacture their own food from simple inorganic materials during the process of photosynthesis and chemosynthesis.
ii. Consumers: Consumers are the heterotrophs (animals and some plants) which cannot manufacture their own food but depend on plants directly or indirectly for their own food.
iii. Decomposers: Decomposers are bacteria and some fungi which break down dead plants and animals in order to feed on them and in the process, nutrients are released to the soil by the producers.
2. Abiotic Components: The abiotic components of an ecosystem include the non-living things which include:
1. Climatic factors like temperature, wind, humidity, sunlight and rainfall.
2. Inorganic materials an nutrients such as carbon (iv) oxide, oxygen, nitrogen, calcium, phosphorus etc.
3. Edaphic factors like soils, rocks, topography.
4. Other factors like dust, storm, fire and water.
Interactions Among The Components Of Ecosystem
There is a unique interaction among the various components of an ecosystem. Green plants use carbon (iv) oxide, water and chlorophyll in the presence of sunlight to produce carbohydrate or starch. Animals feed on these carbohydrates or plants and release carbon (iv) oxide for plants to take in. Micro-organisms and other decomposers break down dead plants and other organisms to release nutrients to the soil. These nutrients are absorbed by plants for use of food production. Plant gives out oxygen during photosynthesis which is used by animals for their normal respiration.