Types, structure, characteristics and components of of major ecosystem, Classification of ecosystem, Forest ecosystem, Grass ecosystem, Dessert ecosystem, Salt water ecosystem

1. MAJOR ECOSYSTEM
Subject ,
Environmental Studies
Government Engineering College,
Bharuch
EC
sem-1

2. WHAT IS ECOSYSTEM?
• An ecosystem is a biological environment consisting of all
the living organisms or Biotic component, in a particular
area, and the nonliving, or Abiotic component. such as air,
soil, water and sunlight with which the organisms interact.
• In an ecosystem, each organism has its own niche or role to
play.
• This very complex, wonderful interaction of living things
and their environment, has been the foundations of energy
flow and recycle of carbon and nitrogen.
• Usually, biotic members of an ecosystem, together with their
abiotic factors depend on each other. This means the absence
of one member or one abiotic factor can affect all parties of
the ecosystem.

3. CLASSIFICATION OF MAJOR ECOSYSTEM
Ecosystem
Natural
Ecosystem
Terrestrial
Forest
Grassland
Desert
Aquatic
Marine Fresh Water
Lotic
(Running Water)
River
Stream
Lentic
(Standing Water)
Lake
Pond
Estuuarine
Artificial
Ecosystem
Agriculture
Aquarium
Urban
Industrial

4. FOREST ECOSYSTEMS
Introduction
A forest ecosystem is the one in which a tall and trees grow that support many animals and birds. The
forest are found in undisturbed areas receiving moderate to hi rainfall. The forest occupies nearly 40% of
the world’s land area. In India it occupies only 19% of its total land area.
Features of different types of Forests
1. Tropical Rain forests
They are foi.ind near the equator. They are characterized by high temperature. They
have broad leaf trees like teak and 1. and the animals like lion, tiger and monkey.
2. Tropical deciduous forests
They are found little away from the equator. They are characterized by a warm climate and rain is only during
monsoon. They have different types of deciduous trees like maple, oak and hickary and animals like deer, fox,
rabbit and rat.
3. Tropical Scrub forests
These are characterized by a dry climate for longer time. They small deciduous trees and shrubs and animals like
maple, oak and hickory and animals like deer, fox, etc.,

5. 4. Temperate Rain Forests
They are found in temperate areas with adequate rainfall. They are characterized by coniferous trees like
pines, firs, red wood etc., and animals like, squirrels, fox, cats, bear etc.,
5. Temperate deciduous forests
They are found in areas with moderate temperatures. have major trees including broad leaf deciduous
trees like oak, hickory and animals like deer, fox, bear, etc.,
Characteristics of forest ecosystems
1. Forests are characterized by warm temperature and adequate rainfall, which make the
2. generation of number of ponds, lakes etc.,
3. The forest maintains climate and rainfall.
4. The forest support many wild animals and protect biodiversity.
5. The soil is rich in organic matter and nutrients which support the growth of trees.
6. Since penetration of light is so poor, the conversion of organic matter into nutrients is very fast.

6. Structure and Function of forest ecosystem
V.S.Saravana Mani, Head & AP/
Chemistry, AEC Salem
I. Abiotic components
Climatic factors (temperature, light, rainfall) and minerals The abiotic components are inorganic and
inorganic and organic substances found in the soil and atmosphere. In addition minerals, the occurrence of litter i
characteristic features, majority of forests.
II. Biotic components
1. Producers: The plants absorb sunlight and produce photosynthesis Trees, shrubs and ground vegetation..
2. Consumers
a. Primary consumers (herbivores) :They directly depend on the plants for
their food. Example : Ants, flies, insects, mice, deer, squirrels.
b. Secondary consumers (primary carnivores):They directly depend on the
herbivores for their food. Examples: Snakes, birds, fox.
c. Tertiary consumers :They depend on the primary carnivores for their food. Examples : Animals, like tiger,
lion, etc.,
3. Decomposers
Examples : Bacteria and fungi.

7. V.S.Saravana Mani, Head & AP/
Chemistry, AEC Salem

8. GRASSLAND ECOSYSTEMS
Introduction
Grassland occupies about 20% of earth’s surface addition. grass, spices, some trees and
shrubs are also included in grassland. grazing helps to improve the net primary
production of the grasslands. But, overgrazing leads degradation of these grassland
resulting in desertification
Features of different types of grassland
1. Tropical grasslands
They are found near the borders of tropical rain . forests. are characterized by high temperature and moderate
rainfall (40 to 100 cm). It is also known as Savanna type. They ye tall grasses with scattered shrubs and stunted
trees and animals like zebras, giraffes, antelopes, etc.,
2. Temperate grasslands
They are usually found in the centers of continents, oil sloped hills.. They are characterized by very cold winters and
hot summers: Intense grazing and summer fires, do not W shrubs or trees to grow.
3. Polar grasslands
They are found in arctic polar regions. They are characterized by severe cold and strong winds along with ice and
snow. In summers several small annual plants grow. They ‘e animals like arctic wolf, weasel, arctic fox, etc.,

9. Structure and function of the grassland Ecosystems
I. Abiotic components
Nutrients, , H, 0, A, P,S, etc.,
These abiotic components are supplied by C02, H2, C, Nitrate, phosphates and sulphates.
II. Biotic Components
1.Producers: They produce food.Example :Grasses, forbs and shrubs.
2. Consumers:.
Primary consumers (herbivores) :They depend on grasses for their food Examples: Cows, buffaloes, deer,
sheep, etc.,
Secondary consumers (carnivores) :They feed on herbivores.
Examples: Snakes, lizards, birds, Jackals, fox, etc.,
Tertiary consumers: They feed on secondary consumers Examples :Hawks, eagle, etc.,
3.Decomposers :They decompose the dead organic matter Examples :Fungi and bacteria.
Characteristics of Grassland Ecosystems
Grassland ecosystem is a plain land occupied by grasses. Soil is very rich in nutrients and organic matter. Since it
has tall grass, it is ideal place for grazing animals. It is characterized by low or uneven rainfall.

11. DESERT ECOSYSTEMS
Introduction
Desert occupies about 35% of our world’s land area. It is characterized by less than 25 cm rainfall. The
atmosphere is dry and hence it is a poor insulator .
Features of different types of deserts
Tropical deserts: Tropical deserts are found in
Africa: Sahara desert.
Rajasthan: Thar desert.
They are characterized by only few species. Wind blow sand dunes are very common.
Temperate deserts: They are found in
South California: Majave.
They are characterized by very hot summer and very Winter time.
Cold deserts: They are found in
Chaina: Gobi Desert
Characteristics of Desert ecosystem
The desert air is dry and the climate is hot. Annual rainfall is less than 25 cm.
The soil is very poor in nutrients and organic matter, Vegetation is poor.

12. Structure and functions of the desert systems ecosystems
I. Abiotic Components
Examples : Temperature, rainfall, sunlight, water, etc.,
The temperature is very high and the rainfall is very low. The nutrient cycling is also very low.
II. Biotic Components
Procedures
Examples :Shrubs, bushes, some grasses and few trees .In deserts mostly Succulent (e.g., cacti)
plants are found available. They have water inside them to stay alive. They have. r on the outside to protect
them from the sun.
Consumers
Examples :Squirrels, nice foxes, rabbits, deer and reptiles.
These animals dig holes in the ground to live in. They come out at night to find food. Most of the animals
can extract water from the seeds they eat.
Decomposers
Examples : Fungi and bacteria
Desert has poor vegetation with a very low amount of dead organic mater. They are
decomposed by few fungi and bacteria.

14. SALT WATER ECOSYSTEM
OCEAN (MARINE) ECOSYSTEMS
Introduction
Oceans cover more than teo third of the earth’s surface. Ocean environment is characterized
by its high concentration of salts and minerals. It supplies huge variety of products and
drugs. It also provides us iron, magnesium, iron, natural gas.
Zones of Oceans
• The oceans have two major life zones.
(a)Coastal zone: It is relatively warm, nutrient rich shallow water. It has high primary
productivity because of high nutrients and sunlight.
(b)Open sea: It is the deeper part of the ocean. It is vertically divided into
• three regions.
(i) Euphotic zone: It receives abundant light and shows high photosynthetic
(ii) Bathyal zone: It receives dim light and is usually geologically active.
(iii) Abyssal zone: It is the dark zone and is very deep (2000 to metres).

15. Structure and function Ecosystems
I.Abiotic components Examples Temperature, light, NaCl, K, Ca, and Mg Salts alkalinity
II.Biotic components
1. Producers: Phytoplanktons (diatoms, unicellular algae, etc., ) and marine plants (sea weeds,
chlorophycela, phaeophyceae).
2. Consumers: These are heterotrophic macro consumers. They depend on producers for their nutrition.
Primary consumers (herbivores) :They feed on producers Examples :Crustaceans, moiluscs, fish
Secondary consumers (carnivores) : They feed on herbivores Examples :Herring sahd, mackerel, etc.,
Tertiary Consumers: They are the top consumers. They feed on small Examples :Cod, Haddock, etc.,
3.Decomposers: They decompose the dead organic matter. Examples:Bacteria and some fungi.
Characteristics of Ocean Ecosystem
1.It occupies a large surface area with saline water.
2.Since ship, submarines can sail in ocean, commercial activities may be earned out.
3.It is rich in biodiversity.
4.It moderates the- temperature