Terrestrial ecosystems are ecosystems that exist on land, as opposed to aquatic ecosystems. They can vary greatly in size and include ecosystems like forests, grasslands, deserts, and tundra. Terrestrial ecosystems are characterized by greater temperature fluctuations, higher light availability, and more readily available gases than aquatic ecosystems. They contain a variety of plant life like flowering plants, conifers, and mosses, as well as many animal species including insects, birds, and mammals. Abiotic factors like temperature, sunlight, water, and wind all influence the living and non-living components of terrestrial ecosystems.

1. THE TERRESTRIAL
HABITAT ECOLOGY

2. Terrestrial Ecosystems
Terrestrial ecosystems
are ecosystems on
land.
They can be as big as a
continent, or as small as
an island!
They make up about
28% of the entire
World’s ecosystems.

3.  Six primary terrestrial ecosystems exist: tundra,
taiga, temperate deciduous forest, tropical forest,
grassland and desert
Terrestrial ecosystems are distinguished from
aquatic ecosystems by the lower availability of
water and the consequent importance of water as a
limiting factor.
Terrestrial ecosystems are characterized by
greater temperature fluctuations on both a diurnal
and seasonal basis than occur in aquatic
ecosystems in similar climates.

4. The availability of light is greater in terrestrial
ecosystems than in aquatic ecosystems because the
atmosphere is more transparent than water.
 Gases are more available in terrestrial ecosystems
than in aquatic ecosystems.
 Those gases include carbon dioxide that serves as a
substrate for photosynthesis, oxygen that serves as a
substrate in aerobic respiration, and nitrogen that serves
as a substrate for nitrogen fixation

5. Terrestrial ecosystems occupy 28.2%, of Earth's
surface.
 Although they occupy a much smaller portion of
Earth's surface than marine ecosystems, terrestrial
ecosystems have been a major site of adaptive
radiation of both plants and animals.
 Major plant taxa in terrestrial ecosystems are
members of the division Magnoliophyta (flowering
plants), of which there are about 275,000 species,
and the division Pinophyta (conifers), of which there
are about 500 species.

6. Members of the division Bryophyta (mosses and
liverworts), of which there are about 24,000 species,
are also important in some terrestrial ecosystems.
 Major animal taxa in terrestrial ecosystems include
the classes Insecta (insects) with about 900,000
species, Aves (birds) with 8500 species, and
Mammalia (mammals) with approximately 4100
species

7. What Animals Live There?
Many different animals
call terrestrial
ecosystems home.
The most common
are:
 Birds
 Mammals of all
shapes and sizes
 insects

8. What Plants Live There?
Many plants also call
terrestrial ecosystems
their home also, we see
many of them everyday!
Common plants are:
 Flowering plants, like
roses
 Mosses, like moss
that grows on rocks
 Conifers, which are
pine trees

9. Abiotic Components
Abiotic components are the non-living components
of an ecosystem, affecting the life of organisms.
Abiotic components can be harmful to the
ecosystem
Abiotic components are:
Temperature, light, water, soil, rocks, sulphur,
nitrogen, phosphorous, proteins, lipids,
carbohydrates ,humic substances etc

10. These specific abiotic factors represent the
geological, geographical, hydrological and
climatological features of a particular ecosystem

11. TEMPERATURE
Most life exists within a fairly
narrow range of
temperatures, from about 0
C to about 50 C. Few
organisms can maintain an
active metabolism below 0 C
for long, and most
organisms’ enzymes are
denatured (they lose their
shape and stop working)
above 50 C. However,
extraordinary adaptations
enable certain species to
live at extreme temperatures

12. It influences organisms in distinct ways :
 Animals have clear distinction between being
cold blooded or warm blooded.
 Migration is seen in some animals.
 Rate of respiration increases with increase in
temperature.
 Water absorption decreases at low
temperature.
 Stimulated the growth of seedlings.

13. TYPES OF VEGETATION
MEGATHERMS: vegetation where temperature
remain high throughout the year. E.g. dominant
vegetation of tropical rain forest.
MESOTHERMS: vegetation where there is an
alteration of low and high temperature season.
E.g. vegetation of tropical deciduous forest.
MICROTHERMS: region where temperature
always remain comparatively lower. E.g. mixed
coniferous forest.
HEKISTOTHERMS: vegetation where
temperature remains low throughout the year.
E.g. alpine vegetation.

14. SUNLIGHT
The sun provides light
and warmth and it is
the energy source for
almost all ecosystems
on Earth. Sunlight
powers
photosynthesis by
plants, the main
producer in most
terrestrial ecosystems

15. 2. Light
Influence on organisms:
Enabling the organisms to seen or to be seen.
Essential for growth of green plants.
In mammals, it plays vita role in formation of
substances such as vitamin D : regulates
quantities of calcium and phosphorous.

16. Depending upon the relative light requirements,
plants have been placed in 2 groups:
a) PHOTOPHILOUS: (heliophilous or sun loving):
these plants grow in high intensities of sunlight.
b) SCIOPHILOUS or shade loving: these plants are
best suited to diffuse or low light intensity.

17. PHOTOPERIODISM: the duration of light affects the
flowering in plants. This is known as
photoperiodism.
on the basis of this plants have been grouped into
following:
a) SHORTDAY PLANTS: plants flower when
photoperiod is less than the critical limit. E.g.
tobacco, soya bean, Xanthium.
b) LONGDAY PLANTS: plants flower when
photoperiod is more than the critical limit. E.g.
beat root, radish.
c) DAY NEUTRAL PLANTS: not affected by the
photoperiod. E.g. cotton, sunflower, tomato.

18. WIND
Many plants use
the help of the wind
to disperse seeds
over long
distances.
Organisms
disperse to find
new habitats rich in
needed resources.
Strong winds can
be very destructive

19. WATER
Water is one of nature’s
most important thing
Essential for life of an
organism’s survival. Water
is necessary for digestion
and absorption of food;
helps maintain proper
muscle tone-, supplies
oxygen and nutrients to
the cells; rids the body of
water; and serves as a
natural air conditioning
system

20. Effect of water:
Affects all the vital functions of an organisms.
Controls the structure and distribution of
communities.
Influences morphology and physiology of
organisms.
Minerals in the soil get dissolved in water and
are than absorbed by plant.

21. Humidity :
In the atmosphere water is present in the form of
water vapours, called atmospheric humidity.
Clouds and fog are the visible form of humidity.
Major source: evaporation of water and
transpiration.
Humidity is expressed in different terms.:
a. Specific humidity: amount of water vapour
present per unit weight of air.
b. Absolute humidity: amount of water vapours
present per unit volume of air at saturation.
c. Relative humidity: amount of water vapours
actually present in air and expressed as % of
the amount which the air can hold at saturation
at existing temperature.

22. Relative humidity is measured by an instrument
called psychrometer.
Effect of humidity on plant life:
Affects structure, form and transpiration.
Plants like orchids, mosses and lichens depends
on atmospheric humidity for their requirement of
moisture.
Evaporation of water, its condensation and
precipitation depends upon relative humidity.

23. BIOTIC COMPONENT
 The biotic components ranges from extremely small
bacteria, which live in the air, water and soil, algae which
live in fresh and salt water, to the terrestrial plants which
range from grasses and herbs that grow after the
monsoon of every year to the giant long lived trees of the
forest
 The living component of the animal world ranges from
microscopic animals to small insects and larger animals
such as fish, amphibians , reptiles, birds and mammals

24.  Biotic component is distinguished into autotrophs ,
heterotrophs and saprotrophs
Autotrophs are also called producers
 These are photosynthetic plants, generally
chlorophyll bearing, which synthesize high-energy
complex organic compounds (food) from inorganic
raw materials with the help of sunlight, and the
process is referred as photosynthesis.
 Autotrophs form the basis of any biotic system.

25.  In terrestrial ecosystems, the autotrophs are
mainly the rooted plants.

26. Heterotrophs
 Heterotrophs are called consumers, which are
generally animals feeding on other organisms
Consumer's also referred as phagotrophs (phago -
to ingest or swallow) or macroconsumers are mainly
herbivores and carnivores
Herbivores are referred as First order consumers or
primary consumers, as they feed directly on plants .
For e.g., Terrestrial ecosystem consumers like cattle,
deer, rabbit, grass hopper, etc.
.

27.  Carnivores are animals, which feed or prey upon
other animals
 Primary carnivores or Second order consumers
include the animals which feed on the herbivorous
animals. For e.g., fox, frog, predatory birds,
smaller fishes, snakes, etc.
 Secondary carnivores or Third order consumers
include the animals, which feed on the primary
carnivores. For e.g., wolf, peacock, owl, etc.

28.  Saprotrophs are also called decomposers or
reducers. They break down the complex organic
compounds of dead matter (of plants and
animals).
 Decomposers do not ingest their food.
 Instead they secrete digestive enzymes into the
dead and decaying plant and animal remains to
digest the organic material.
 Enzymes act upon the complex organic
compounds of the dead matter.

31. Classification of terrestrial communities
on the basis of habitat
Terrestrial organisms are found living on the
surface of earth, below it or in the sky.
 therefore, on the basis of habitat, they are
divided into 3 categories:
a) Subterranean communities
b) Surface communities
c) Aerial communities

32. a) Subterranean communities:
Animals which live about 5 to 6 inches deep
inside the earth.
These animals are adapted to various modes of
life living inside earth. These adaptations depend
upon the nature and type of soil they live in.
On the basis of the size, the subterranean
communities are further classified as follows:

33. i. Microbiota subterranean communities
 It includes algae, bacteria and fungi.

34. ii. Mesobiota subterranean communities:
 It includes nematodes, oligochaetes, small
insect larvae and some arthropods.

35. iii. Macrobiota subterranean communities:
 It includes roots of some plants, large insects,
earthworms, moles, ground squirrel and pocket
gophers.

36. b). Surface communities:
 communities which live on earth.
 on the basis of climatic factors it can be divided
into following:
i. Tropical : temperature : 48 degree Celsius or
more ; rainfall: 200-400 cm per year. Climate is
warm.
ii. Temperate: temperature: 40 degree Celsius or
more; rainfall: 76 cms. Summers are warm and
winters are cold.
iii. Alpine: snowfall takes place, avg rainfall is
25cm or less.

40. c). Aerial communities:
 organisms which fly in the sky.
They come on land, trees or rocks for feeding,
breeding and resting.
Insects, moths, birds and bats are main sky
fliers.

42. Examples of Terrestrial Ecosystems
Forests
Deserts
Grasslands