Terrestrial Ecosystem

Ecosystem

Any ecological unit that includes all the organisms, the communities in a given area which interact among themselves and with the physical environment, so that a flow of energy leads to clearly defined trophic structure, biotic diversity and material cycle within the system, is known as ecological system or ecosystem.

In other words, ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system

Components of Ecosystem

1. Abiotic Components

2. Biotic Components

Factors of Abiotic Components

1. Climatic Factors

2. Edaphic Factors

Climatic Factors

1. Rain

2. Light

3. Wind

4. Temperature

Edaphic Factors

1. Soil

2. PH

3. Minerals

4. Topography

Biotic Components

1. Producers (Autotrophs)

2. Consumers (Heterotrophs)

3. Decomposers (Saprotrophs)

Types of Consumers

1. Primary Consumers

2. Secondary Consumers

3. Tertiary Consumers

4. Quartenary Consumers

Types of Ecosystem

1. Natural ecosystems

2. Artificial ecosystems

Natural ecosystems

These types of ecosystems operate by themselves without any major interference by man.

Classification of Natural Ecosystems

1. Terrestrial ecosystems

2. Aquatic ecosystems

Terrestrial ecosystems

such as forests, grasslands, deserts, a single log, etc.

Aquatic ecosystems

which may be further distinguished as follows : (a) Fresh water ecosystems. (b) Marine ecosystems.

Artificial ecosystems

These are also called man-made or man-engineered ecosystems. These are maintained artificially by man where, by addition of energy and planned manipulations, natural balance is disturbed regularly, e.g., croplands such as sugarcane, maize, wheat, rice-fields ; orchards, gardens, villages, cities, dams, aquarium and manned spaceship.

Terrestrial ecosystem

Terrestrial ecosystem refers to the ecosystem on land.

It comprises 28% area of the world.

Types of terrestrial ecosystem

1. Biogeographic realms

2. Biomes

Biogeographic realms

has six subdivisions:

1. Palaearctic realm

2. Nearctic realm

3. Neotropical realm

4. Afrotropic realm

5. Indomalaya realm

6. Australasia realm

Palearctic realm

The largest Geographical Distribution, including whole Europe, Soviet Russia.

➢ There occurs a great variety in the number of species of flora in Palearctic realm.
➢ The number of fauna is also variable.

➢ One bird family, the Accentors is endemic to the Palearctic region.

Holarctic endemic bird families

1. Divers

2. Grouse

3. Auks

4. Waxwings.

endemic mammal orders in Palearctic Realm

1. Calomyscidae

2. Prolagidae

3. Ailuridae

Nearctic realm

covers most of North America, including Greenland, Central Florida and the highlands of Mexico