Terrestrial Habitat

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In today’s Biology class, We will be learning about Terrestrial Habitat. We hope you enjoy the class!

CONTENT

Terrestrial Habitats
Marsh
Forest
Grassland
Arid land

TERRESTRIAL HABITATS

Organisms of the land are called terrestrial organisms. They include plants and animals that are found living on the ground and under the ground.

Basically, terrestrial habitat is subdivided into four main parts, namely;

marsh
forest
grassland/ savanna
arid land/ desert

EVALUATION

What are terrestrial organisms?
List four types of terrestrial habitats

MARSH

A Marsh is low land, flooded in rainy season and usually waterlogged because of poor drainage. The vegetation is predominantly of grasses and shrubs. When trees grow in a marsh, it is called a swamp. Marsh is a transition between the aquatic habitat and terrestrial habitat.

FORMATION OF A MARSH

Marshes develop as a result of water overflowing its banks to accumulate on the adjoining coastal or low land area such as flood plains of rivers. This can be enhanced with extensive rainfall.

When ponds and lakes are filled up with soil and organic debris of plants, marshes can also be formed. Marshes formation is, therefore, a gradual process. Marshes can either be freshwater or saltwater marshes.

CHARACTERISTICS OF A MARSH

A marsh is a lowland.
It is always flooded, wet and waterlogged.
It sometimes has a pool of standing water.
It has a high relative humidity
Its water sometimes contain many decaying organisms
The water has a foul smell

ORGANISMS OF THE MARSH

There are various plants and animals in this habitat. The plants include algae, grasses, water lettuce, water lilies, white and red mangrove, raphia palms e.t.c.

Animals found in the marsh include mangrove crabs, lagoon crabs, hermit crabs, mud-skippers, fishes, frogs, snakes, crocodiles, mammal e.t.c.

Adaptive features of organisms of the marsh include

They must be able to tolerate the salinity of the soil or water
They have to tolerate low oxygen concentration in the soil or water

Plants of freshwater marsh have other adaptive features similar to those of freshwater habitat. Likewise the plants of saltwater marsh.

Saprophytic organisms (e.g. bacteria) which live on dead organic matter in marshes have to adapt to the anaerobic condition.

FOOD CHAINS IN MARSHES

Flowering plants → insects → frogs → crocodiles
Humus → earthworms → frogs → snakes

EVALUATION

How is a marsh formed
State four characteristics of a marsh
List four plants and animals found in the marsh

FORESTS

A forest is a community of plants in which trees species are dominant. There are different kinds of forests whose distribution is determined mainly by climatic factors such as temperature, rainfall and at times by soil elevation and man’s activities such as farming, lumbering, bush burning, construction of roads and building.

The major type of forest in Nigeria is the rain forest

CHARACTERISTICS OF A FOREST

The forest is rich in epiphytes and climbers
The interior of the forest has high humidity, low light intensity and damp floor.
Presence of tall trees with canopies and existing in layers (stratified).
Trees are mesophytes with broad leaves.
The trees have buttress roots to support their heavyweight and height.
The trees have thin barks for gaseous exchange and transpiration.

PLANTS DISTRIBUTION AND ADAPTATION

Forest plants (trees) include African walnut, mahogany, teak, obeche, iroko, oil palm, ferns (pteridophytes), bryophytes (mosses and liverwort), epiphytes (orchid), fungi and mistletoe e.t.c. these plants adapt to life in the forest in the following ways;

Possession of strong taproot systems and buttress roots.
Possession of tall unbranched trunks
Possession of broad leaves
Epiphytes have a mechanism (the aerial roots) storing water and absorbing moisture from the air while growing on tree branches.
Mistletoe (plant parasite) develops a root system that can penetrate the stem of a plant withdrawing manufactured food directly from phloem vessels of the host plant.

ANIMALS DISTRIBUTION AND ADAPTATION

Most forest animals are arboreal (living on trees) and these include bats, monkeys, snakes, squirrels, birds, tree frogs, chameleons. Some live in the soil e.g. earthworms and beetles while others live among the litters on the ground e.g. millipedes, ants, snails.

These animals adapt to the forest in the following ways

Monkeys have prehensile tails and long limbs for climbing and jumping.
Bats modify their limbs into wings for flight
Green snakes have protective colouration to camouflage
Chameleon has a prehensile tail and opposable digits for grasping as well as protective colouration to camouflage
Apes move in groups for protection, with a high sense of sight
Earthworms and snails have water permeable cuticle to reduce water loss and prevent desiccation.
Birds have powerful wings for flight

FOOD CHAINS IN A FOREST

Green plants → grasshoppers → toads →hawks
Green plants → monkeys → lions

EVALUATION

Describe a forest habitat using its characteristics
Give two examples of a food chain in a forest

GRASSLAND [SAVANNA]

This is a plant community in which grass species are dominant, but trees and shrubs may be present.

CHARACTERISTICS OF GRASSLAND

Temperature is usually high and sunshine is intense.
The relative humidity is low and rainfall scanty (60 – 150cm annual rainfall).
Abundant grassland with few short trees sparsely distributed
Bush fire is frequent and trees are fire-resistant
Deciduous plants (plants that shed their leaves in dry seasons) are present.
Plants possess underground stems and deep roots to search out for water
Trees have modified leaves for adaptation to the environment

TYPES OF SAVANNA

Basically, there are four major types of savanna in Nigeria, namely;

Southern Guinea savanna
Northern guinea savanna
Sudan savanna
Sahel savanna

Southern Guinea savanna is the largest biome in Nigeria

PLANTS DISTRIBUTION AND ADAPTATION IN GRASSLANDS

The grassland plants include acacia, elephant grass, guinea grass, spear grass, palms, baobab trees e.t.c. their adaptive features include

Trees have thick corky barks to resist severe fire
Grasses with underground stems to escape fire and drought
Leaves with a waxy surface in addition to cuticle covering to reduce transpiration
Reduced or small leaves to reduce transpiration
Presence of curly leaves to conserve water
Leaves fall (deciduous) in drying season to conserve water
Baobab trees have broad and succulent leaves to conserve water

ANIMALS DISTRIBUTION AND ADAPTATION IN A FOREST

Animals found in the forest adapt to this habitat in the following ways

Termites lived in air-conditioned nests called anthills for cooling the animals.
Rats burrow into the soil to avoid excessive heat and fire
Zebras and giraffes can camouflage using their colours.
Lions, tigers and leopards have powerful claws and teeth for attacking animals.
Kangaroos have long legs to help them escape from danger and also have a pocket of flesh to shield their young ones from hot weather and attack.
Elephants and lion move in groups or herds to achieve strength in number

FOOD CHAINS IN GRASSLAND

There are several food chains due to numerous animals

Grass → grasshoppers→ lizards → snakes
Grass → grasshoppers → toads → birds
Grass → zebras → lions

ARID LANDS [DESERTS]

These are areas of very low rainfall and high evaporation rate. They are the driest habitats, receiving less than 25cm annual rainfall. Arid lands are of two types;

Hot deserts e.g. Sahara desert (North Africa), Kalahari desert (South Africa)
Cold deserts e.g. desert in North America

CHARACTERISTICS OF A DESERT

Water is very scarce
Temperature is very high by the day and very low by the night
Vegetation is very scanty
The soils are sandy or rocky
Strong winds occur frequently and sunshine very intense
Presence of drought resistance plants (xerophytes)

PLANTS DISTRIBUTION AND ADAPTATION IN DESERTS

Deserts plants include thorny bushes, cacti, scattered dwarf acacia, date palm, wiring grasses, baobab trees and euphorbia species. They adapt to this habitat in the following ways;

Plants have thin leaves to reduce transpiration
Cacti leafless have thorns to reduce transpiration and thick succulent stem to store water
Acacia (drought resistant) has deep roots which absorb underground water
The baobab tree has waxy leaves which can be hairy or needle-shaped to reduce the rate of transpiration
Wiring grass has narrow and slender leaves to reduce transpiration.

ANIMAL DISTRIBUTION AND ADAPTATION IN DESERTS

The deserts animals include camel, rodents, lizards, snakes, zebras, desert tortoise, grasshoppers, wasps, ants e.t.c. They survive in the following ways;

Most desert animals excrete solid wastes to conserve water.
Kangaroos, rats remain in burrows during the day to avoid excessive heat
Reptiles have scales to reduce water loss
Camels can survive several days without drinking water. They can withstand a wide range of body temperature up to 40^o

FOOD CHAINS IN ARID LANDS