Environmental studies Biosphere, biomes and ecosystem

Environmental studies

Biosphere, biomes and ecosystem

Biosphere

The biosphere

can be defined as that part of the earth where the living organisms are found.

It is made up of 3 parts.Atmosphere

(air

)

Hydrosphere (water) Lithosphere (rock and soil)

Atmosphere

The atmosphere is a layer of air around the earth’s surface

Lithosphere

The lithosphere is all the soil and rocks that makes up the upper layers of the earth’s surface.

Hydrosphere

Hydrosphere is all the waters of the seas, rivers and lakes.

Here are some examples of the various sources of

natural water on the Earth

Terminology:

Biosphere:

the part of the earth on which living organisms live.Atmosphere: layer of air around the earth’s surface.

Lithosphere: the soil and rocks forming the upper layers of the earth’s surface.Biome: any region with a distinct climate and all the organisms that live in that area.Savanna: vegetation type with well developed grassy layer and an upper layer of woody plants.

Endemic: organisms found in only one area in the world and no where else.Mutualism: relationship between two organisms in which both benefit.Lichen: a close mutualistic association between an algae and fungi

Biomes

Different parts of the earth have different climates

Plants and animals are adapted to live in particular climates.Therefore different plants and animals will

live in different regions.These regions with their particular climates and living organisms that are adapted to live in there is called a biomeA biome can be defined as a region with a distinct climate and all the organisms that live in that region.

Biomes of Southern Africa

The map shows the biomes of the Southern African region.

The countries that make up the Southern African region are:

South Africa Namibia Botswana Lesotho Swaziland Zimbabwe MozambiqueThere 8 different biomes

in this region.

The different biomes of the Southern African region

Grassland

SavannaForest

ThicketFynbosNama-karooSucculent KarooDesert

The Grassland Biome

This biome is found in

parts of 5 provinces in

South Africa and 2countries in the SouthAfrican region

Grassland: Temperature, rainfall and soil type.

Temperature and RainfallThe summers are

hot with high rainfall.The winters are cold with frost

.SoilThe soil has a high humus content.Unfortunately in the areas with high rainfall the soil is easilyleeched and becomes

acidic.

Vegetation

This biomes is dominated by

grasses.There are 2 types of grasses here.They are the

sweet grasses and the sour grassesThe sweet grasses grow on fertile soil and therefore have good food value and are therefore preferred by the animals.The sour grasses grow on infertile soil and do not have much food value and are avoided by animals.

Animal Life

Blesbok, black wildebeest and springbok are found here.Also has a large variety of birds including the blue crane.

The sun gazer lizard is also found here

Savanna Biome

Savanna refers to a type of vegetation with a well developed

grassy layers and an upper layer of

woody plants.It is the largest biome in South AfricaIt is found mainly in Mpumalanga and Limpopo.Its also found in the coastal belt of

KZN and Eastern Cape Province.

Savanna: Temperature, Rainfall and Soil

Temperature and Rainfall:

In this area summers are hot and wet and winters are cool

with little or no rainfall.Soil:The soil is mostly sandy.It has a moderate amount of nutrients.

Some parts have very rich soil.

Vegetation:

This biome is dominated by grasses, large shrubs and trees.The lack of sufficient rainfall and fires

prevent the trees from being the main type of vegetation.This type of vegetation is suitable for grazing animals example: cattle and buck.

The marula tree grows in this biome.

Baobab Tree

Grows up to about 15m tall.The tree trunk can grow up to 30m wide.

Animal Life

The mammals found in this biome are commonly known as the big five.

This area is also home to many large birds of prey.

Forest Biome

It occurs in

patches in spread over four provinces.

Something for you to do:Carefully study the mapand answer the followingquestion:Name the provinces inwhich this biome occurs.

Solution:

The four provinces are:a. Western Cape: in the George-Knysna-

Mossel Bay areab. KwaZulu Natalc. Limpopo

d. Eastern Capee. Mpumalanga and also occurs as f. Patches of forest in the deep river valleys

Forest Biome: Temperature, rainfall and soil:

Temperature and RainfallTemperature varies form about 20

⁰C to 30⁰C.Temperature can get higher.Rainfall seasons vary, in some forests it rains only in winter,

while in other forests it rains in summer only and others it rainsall year round.SoilThis biome has a thick layer of soil and it may be shallow in otherparts.The soil here is very rich, because it is mixed with the fallingleaves, fruit and bird and mammal dropping.

Forest Biome: Vegetation

Dominated by large shrubs and trees.The largest South African Forest tree is the Outeniqua yellowwood.

These large trees form a canopy, under this canopy large ferns and tall woody shrubs

form the next layer.Herbaceous and bulbous plants, together with grasses form the ground level.The climbing plants and epiphytes are also found here.

Something for you to do:

Herbaceous plants have…green, fleshy stems.

woody brown stems.dicot stems

broad, flat leaves.A canopy is a…roof like layer of leaves over the foresttent shading one from the sunpart of a dicot plant

lowest layer of trees in a forest

Something for you to do:

Epiphytes areA. Ground cover in the forest

B. Plants with no stomataC. Climbing plants found in a forest.D. Plants with no leaves.

Solution:

AA

C

Forest Biome: Animal life

Bush buck, bush pig, blue duiker, baboon, vervet monkey, and leopard are some of the larger mammals found here.

Many birds are found in this biome.Some examples are: the fruit eating rameron pigeon, the insect eating paradise fly-catcher and seed eaters.The

Knysna lourie and the Knysna woodpecker are some examples of endemic birds found here.

The Thicket biome

It occurs in finger-like projections along the coasts of KwaZulu-Natal, Eastern Cape and some other areas.Most of the thicket biome occurs in the

river valleys.

Thicket Biome: Temperature, Rainfall and Soil.

Temperature and RainfallThese areas experience fairly high rainfall.Since periods of little rain does occur , it means rainfall

is not high enough the vegetation does not develop intoforests.During the dry periods the life forms living here get theirmoisture from the mists and fog that often occurs in this

biome.

Thicket biome: Temperature, Rainfall and Soil

SoilThere is a thick layer of soil.

The falling leaves, fruit and droppings of birds andmammals mixes with the soil andincreasing its humus content.This makes the soil very rich.

This rich soil can support woody vegetation.

Thicket Biome:

VegetationThis biomes has many short trees, low intertwining shrubs and vines.

The vines often have spines for protection.The vegetation does not have distinct layers like the forest.

Common trees found in this area are the Spekboom and many species of Euphorbia.Cape honeysuckle and Plumbago are some examples of shrubs found in this biome.

Spekboom-left

Cape honeysuckle

Plumbago

Thicket biome: Animal life

Some examples of animals found here are monkeys, birds and squirrels.

These animals feed on the fruit of the trees.

The black rhino, elephants and kudu were once found here in large numbers.Now they are only found in protected areas e.g.. Shamwari Private Game Reserve.

Nama Karoo Biome

It is a semi desert area.It forms a large part of the ____________.

Nama Karoo: Temperature, Rainfall and Soil Type

Temperature and RainfallThis is a semi desert area.

It receives very little rainfallSummers are very hot and winters are very cold.

SoilThe soil is rich in nutrients.

Vegetation

Vegetation is dominated by

grasses and

dwarf shrubs.The stone plants are a group of plants that occur here that use camouflage, since it looks like pebbles around it.

Nama Karoo: Animal Life

The animals that are found here are those that can survive extremes of temperature and very little water.

Some examples of the animals found here are:Foxes, jackals, dassies and hares.

Succulent Karoo Biome

Found on the

west coast ofthe

Northern Cape Provinceand the northern parts ofthe Western Cape Province.

Succulent Karoo: Temperature, Rainfall and Soil type.

Temperature and Rainfall.Hot in summer and cold in winter.

Rainfall is very low.SoilThe soil is very fertile.

It is red clay with rocks in between.There are large parts of shale in other parts.White quartz pebbles can be seen

Succulent Karoo: Vegetation

This area is dominated by dwarf shrubs.

40% of the species are endemic to this areaThe

Namaqualand region of this biome is world famous for the colourful wild flowers.Annual plants germinate, grow, flower and seed in the moist winter and spring.They die off in the dry months with the seeds surviving and grow again the next winter.

Succulent Karoo: Vegetation

The perennial plants survive the dry season by using

water stored in the leaves or stems.These plants are called succulents.

These plants are adapted to reduce transpiration byhaving a: thick waxy cuticle reducing the number of stomata.The non-succulent perennials have very small leaves to reduce water loss

by transpiration.Those with large leaves lose their leaves during the dry months.

Succulent Karoo: Animal Life

Animal life is not as abundant

as the plant life.The bat eared fox, the meercat

and the barking gecko are examples of the animals found here.

Fynbos Biome

Found in the major parts of Western Cape.

Fynbos Biome: Temperature, Rainfall and Soil

Temperature and RainfallHot and dry summers

Winters are cold and wet.SoilThe soil is very varied of different pH and quality

The soil is sandy and alkaline along the coastThe soil is sandy but acidic inlandIn the lowlands the soil is fertile and more or less neutral.The soil on the mountain tops are acidic and of a very poor quality

Something for you to think about

How does the varied quality and pH of the soil in this biome affect the plant life?A. Has no effect of the plant life

B. Ensure there is a wide variety of plant life.C. Reduces the number of plant species in this biome.D. Prevents the plants from reaching their full growth.

Solution:

How does the varied quality and pH of the soil in this biome affect the plant life?A. Has no effect of the plant lifeB. Ensure there is a wide variety of plant life.

C. Reduces the number of plant species in this biome.D. Prevents the plants from reaching their full growth

Fynbos Biome: Vegetation

Fynbos refers to dwarf shrubs with fine leaves.However when it is used to describe a biome it refers to all the vegetation found in this biome.

This includes: dwarf shrubs large shrubs

treesThere is very little grass here butLeafless tufted grass plants occur here.

Fynbos: Animal Life

There is a limited variety of species found in this biome.

Examples of animals found in this biome are:

Grysbok, klipspringer, bontebokThere are a large number of bird species.

Desert Biome

This biome occurs mainly as the Namib Desert.The Namib desert is found along the west coast of Namibia

Some scientist believe that the Succulent Karoo Biome and the very parts of the Savanna Biome form parts of the Desert Biome.

Desert Biome:

Temperature, Rainfall and SoilTemperature and Rainfall

Average temperature in the Namib Desert ranges from20⁰C to about 34⁰C.The rainfall is low and unpredictable.The air is very dry because of the high temperature and

low rainfall.Therefore it has a very high evaporating power.SoilThe soil is sandy and has a very low water holdingcapacity.

Desert Biome

: vegetation

A large part of this biome has no visible plant life.

However they do carry seeds.When there is sufficient rainfall, these seeds will germinate and grow into grasses very quickly.The land will now be covered by large amounts of golden coloured grasses and will not resemble a desert at all.

The desert biome after high volume of rainThe desert in times of no rain

Flowers in the desert after rainfall

Desert Biome: Vegetation

Shrubs grow in areas into which water drains.Welwitschia is an example of such a shrub.A few trees may also grow here.

The African moringo, camelthorn, mustard trees and Euphorbias are examples of some of the trees that grow here.

Welwitschia

African moringocamelthorn

Desert Biome:

vegetation

The large variety of lichens are also found in this biome.A lichen is a very close association between a fungi and an algae.They have such a close relationship that they actually form a new organism.

The fungi provides the algae with water and the algae uses the water to make food by photosynthesis.The algae then provides the fungi with food.The fungi gets the moisture from the dew and fog.This is an example of mutualism.

Something for you to do:

A quick question for you to answer:Explain what is mutualism and why the lichen is an example of mutualism.

Solution:

Mutualism is a symbiotic relationship between two organisms in which both organisms benefit.The lichen is considered to be an example of mutualism because the fungi is heterotrophic and unable to make its own food, but it is able to absorb water.The fungi provides the algae with water. The algae uses the water to make food and provides the fungi with food because both organisms benefit this is an example of mutualism.

Desert Biome:

Animal lifeThere are many endemic species of animals are found here.

Some examples of organisms found in this biome are lizard, geckos and snakes.

Golden mole

Web foot geckoPeringuey’s adder

Something for you to do

Write down the correct biological term for each of the following:The part of the earth in which living organisms are found.

The soil and rocks of the upper layers of the earth’s surface.A region with a distinct climate and all the organisms living their

Southern Africa's largest biome.Species occurring in one area only and no where else in the worldThe name given to the vegetation found in the Western cape only and nowhere else in the world

Complete Activity 3.1.1

Other types of biomes

Aquatic biomes: water covers a major part of the Earths surface, these became home to many different biotic species.2 types of aquatic biomes:

Fresh water region: low salt concentration, includes ponds, lakes, streams and rivers and wetlands.Marine regions: Oceans, which cover nearly ¾ of the Earths surface. Estuaries: partially enclosed areas where salt water and fresh water meets

Ecosystem

An ecosystem is an area in which there exists relationships between

living organisms themselves and the living organisms and the non-living environment

.Some examples of ecosystems are: a river, a grassland, a fallen rock.The study of all the relationships in an ecosystem is called ecology.

Characteristics of Biotic components

RespirationMovementReproduceProduce offspring

Ecotourism:

South Africa is a country that is rich in biodiversity.

There two reason for this rich biodiversity.These two reasons are: a. The country as a very varied climate, for example the

tropical weather b. The country also has a very varied topography: the low lying belt of the coast, the escarpment and finally the plateau inland.

Varied climate and environments varied vegetation  varied animas.This rich biodiversity attracts people from all over the world to come to South Africa.

Ecotourism:

Ecotourism is the attraction of visitors to ecologically sensitive areas.

This type of tourism benefits the local people, the visitor and the environment.

Benefits of ecotourism

For local people: Job opportunities and business opportunities For the visitors: enjoyment and learning experience of what the country has to offerFor the environment: knowledge and awareness of environmental issues are created; monies received from ecotourism can be used to build more protected areas.

ETHICS/ DISADVANTAGES?

While ecotourism can have many

benefits such as promoting public knowledge, creating awareness and even job opportunities, some tour operators use ecotourism to promote their own business.

Ethical issues

The local people are employed at the lowest level and in the lowest paying jobs

Accommodation and catering are usually contracted to large international companies therefore these business do not contribute to the economy of the country.

Very little or no attempts are made to create interest in the local culture.

Usually the tour activities has a negative impact on the environmentOnly a small percentage of the profits or none at all is used for activities that protect the biodiversity.

These tour operators are guilty of the following:

Activity 3.1.2