MORE BIOMES 27 AUGUST 2014

Lesson Description

In this lesson we:

Focus on key concepts and questions relating to aquatic biomes.

Summary

The Biosphere

The part of the planet that supports life e.g. atmosphere(air), lithosphere (land) and hydrosphere(water)

The atmosphere is the body of air which surrounds our planet. Most of our atmosphere is located close to the earth's surface where it is most dense. The air of our planet is 79% nitrogen and just under 21% oxygen; the small amount remaining is composed of carbon dioxide and other gasses.

The hydrosphere is composed of all of the water on or near the earth. This includes the oceans, rivers, lakes, and even the moisture in the air. Ninety-seven percent of the earth's water is in the oceans. The remaining three percent is fresh water; three-quarters of the fresh water is solid and exists in ice sheets

Aquatic organisms depend on the hydrosphere for life

The lithosphere is the solid, rocky crust covering entire planet. This crust is inorganic and is composed of minerals. It covers the entire surface of the earth.

This is where terrestrial organisms live

Interconnections of the Spheres

The lithosphere, hydrosphere and atmosphere form the biosphere.

The soil, water and air support life on earth.

Life on earth is linked in each of the three spheres.

All four spheres can be and often are present in a single location. For example, a piece of soil will of course have mineral material from the lithosphere. Additionally, there will be elements of the hydrosphere present as moisture within the soil, the biosphere as insects and plants, and even the atmosphere as pockets of air between soil pieces.

There are two components to the biosphere o A biotic or living component – animals, plants microorganisms etc. o An abiotic or non-living component – water air temperature, soil etc. o The biotic and abiotic factors of the biosphere form the global ecosystem

Living organisms are not evenly distributed throughout the biosphere.

Scientists have divided the earth into regions according to their climate, soil, plants and

animals that live their – these

regions are called biomes

Biomes are sub-divided into

ecosystems.

Ecosystems are communities

of organisms that interact in a

particular environment.

An organism lives in a certain

place where it gets its food,

space and where it reproduces

– this is called its habitat

Scientists divide biomes into :

o Terrestrial biomes that

occur on land –

grasslands, savannah,

fynbos

o Aquatic biomes - marine, wetlands, coastal

South African Biomes – Terrestrial

Biomes Characteristics

Savannah

• Savannas are the wooded grasslands of the tropics and subtropics that account for 46% of the South African landscape.

• Stretches from the Kalahari in the west into the north and north-east of Limpopo

• Rainfall2oo-1000mm

• Summers hot and wet

• Winter cool and dry

• Soil fertile

• Vegetation: Grasses, thorn tress, large shrubs, trees (marula, baobab)

• Animals:‘Big 5” blue wildebeest, eland, hippo, kudu, cheetah, zebra, giraffe, wild dogs

Grassland

• The grasslands cover the high central plateau of South Africa, inland areas of Kwazulu-Natal and the mountain areas of the Eastern Cape Province

• Variety – rainfall varies, thunderstorms and hailstorms

• Winters cold with or without frost, fires common

• Summer – hot and wet

• Soil type- fertile

• Plants - Grasses (rooigras)

• Animals - Blesbok, black wildebeest, springbok

Nama-Karoo

• The Nama-Karoo covers most of the vast central plateau region of the Western and Northern Cape Provinces.

• Semi-desert – flat and rugged • Ground dry and rocky

• No permanently flowing rivers (no rain)

• Rainfall less than 500mm

• Summer high temp

• Winter freezing cold

• Soil – rich in lime, thin layer of soil over rock, infertile

• Plants – xerophytes, low bushes, grass and shrubs - Stone plant, sweet thorn, Karoo daisy

• Animals - black-eared jackal, leopard, baboon, vervet monkey, tawny eagle

Succulent Karoo

• This biome occurs mostly west of the western escarpment through the western belt of the Western Cape and inland towards the Little Karoo.

• The succulent Karoo is restricted to the year-round and winter rainfall areas and have the greatest summer aridity

• Rainfall - dry, 50mm-350mm rainfall

• Summers – hot and dry

• Soil – rich in lime, infertile and erodes easily

• Plants – xerophytic, Namaqualand daisies, succulents, lichens

• Animals – small rodents- mice squirrels, Bat- eared fox, suricate, barking gecko

Fynbos

• Fynbos occupies 5,3 % of South Africa, occurring almost exclusively in the south-western and southern parts of the Western Cape Province.

• Winters cold and wet – 210-3000mm

• Summers hot and dry

• Soil – infertile soil that is leached of all its nutrients – inhibits growth of larger plants

• 68% of plants endemic to the fynbos biome

• One of the six floral kingdoms in the world

• Fires common in summer – needed to stimulate germination

• Plants- Proteas, shrubs and trees, rooibos tea, buchu, olives, table wine, thatching reed

• Animals - Klipspringer, Cape mountain zebra,

South African Biomes – Aquatic

Marine and Coastal Biomes

Include – oceans, coral reefs and estuaries

Biomes include salty water.

Algae live in the water and produce oxygen and food

South African marine biome contains 12% of the worlds fish species. Our coastline is 3000km long

Water on the east coast is warm because of the warm Indian current and the water on the west coast is cold because of the Benguela current.

The west coast water are rich in nutrients which provides food for plankton and fish

Organisms

Plankton- phytoplankton (algae), zooplankton (microscopic crustaceans) – fish and large fish – sharks, dolphins, whales – animals living on the bottom – crabs, oysters, sponges, lobster etc.

Concentration of nutrients

Coral Reefs

Shallow waters off the northern coast of Kwa-Zulu Natal

Coral reefs are formed from calcium carbonate of tiny corral animals

Large biodiversity

Animals – micro-organisms, invertebrates, fish, sea urchins, sea-stars, octopusi

Open Sea Zone

Open ocean

Temperature is generally cold

Plankton main food provider for fish, dolphins and whales

leopard, geometric tortoise, baboons, porcupines, lynxes , Cape sugar bird

Forests

• Smallest biome. Mountainous forests along the Southern Cape coastline – Knysna and Tsitsikamma

• Rainfall – throughout year, mainly winter • Forests cool and moist, humid • Soil deep and fertile • Plants - Outeniqua Yellowwood, epiphytes,

herbaceous and bulbous plants • Animals - Blue duiker, bush-pig, Knysna Lourie

and woodpecker , paradise flycatcher

Thickets

• Along the coast of Kwa-Zulu Natal and Eastern Cape

• Rainfall fairly high but not sustainable for forests

• Soil – shallow and varies from sandy loam to sandy clay that is rich in lime

• Plants – varies, shrubland to low forests, evergreen and succulent trees and shrubs, plants have thorns. Short trees, spekboom, Cape honeysuckle, Plumbago

• Animals - Elephants, antelopes, monkeys, squirrels, bushbuck , African python

Wetlands

Area of land which is covered predominately by shallow water.

Include mountain springs, marshlands, flood plains, estuaries to swamp forests that are linked by river and streams.

Rich in biodiversity- o Birds o Large amount of carbon o These wetlands share common and

important functions in river catchments by providing a regular water supply, by filtering the water naturally

o By reducing the effects of floods and droughts.

Estuaries

Are areas where freshwater of streams or rivers meet with the salt water of the sea

Water conditions, temperature and salt content, change constantly with the tides

Rich in nutrients

Plants – algae, seaweed, marsh grass and mangroves

Animal – prawns, sponges, mussels, barnacles, crabs

Test Yourself

Question 1

A population is made up of

A. Individuals

B. Communities

C. Ecosystems

D. Different species

Question 2

The food chain that is represented by the pyramid of numbers below is …

A. grass → cows → man

B. tree → aphids → ladybirds

C. plankton → fish → fish eagle

D. grass → buck → ticks

Question 3

The effect of the length of day on plants is called:

A. Phototropism

B. Photoperiodism

C. Aestivation

D. Migration

Question 4

Why is it difficult to incorporate nitrogen gas from the atmosphere into the nitrogen cycle of the biosphere?

A Nitrogen is not very abundant in the atmosphere.

B Few organisms can directly utilise atmospheric nitrogen gas.

C Most plants do not require organic nitrogen compounds for survival.

D Oceans quickly absorb nitrogen gas.

E Living organisms quickly absorb nitrogen gas.

Question 5

Organisms that use inorganic nutrients and an outside energy source to produce sugars and other organic nutrients for themselves and other members of the community are…

A autotrophs

B saprophytes

C heterotrophs

D herbivores

Question 6

In an ecosystem, bacteria and fungi are the …

A. omnivores

B. herbivores

C. producers

D decomposers

Question 7

Which of the following food chains is correct?

A. Producers → carnivores → herbivores

B. Plants → secondary consumers → tertiary consumers

C. Producers → herbivores → secondary consumers

D. Plants → herbivores → primary consumers.

Improve your Skills

Question 1

Use the map below to help answer the questions that follow:

1.1 Name the two types of forest found in South Africa. Describe the soil and climatic conditions of

these biomes. 1.2 What influence could the cold Benguela current on the west coast of South Africa have on the

vegetation? 1.3 In what way is the fynbos region not suitable to the growth of plants? 1.4 Why is fire important for the fynbos vegetation? 1.5 What is the difference between the vegetation of the grasslands and savannah? 1.6 Describe the effect elephants will have on the savannah during times of drought. 1.7 How are plants adapted to survive the harsh Karoo regions? 1.8 How are animals adapted to withstand the extreme high temperature conditions in the Karoo? 1.9 What is the importance of fog from the Atlantic ocean in the succulent karoo

Question 2

2.1 In African grasslands impala, giraffe and zebra feed on Acacia trees. Impala and zebra also graze on grasses.

2.1.1 State ONE way in which competition for food is reduced between zebras and giraffes. (1)

2.1.2 The Acacia tree is adapted to withstand long periods of drought. Suggest an adaptation the Acacia tree may show that allows it to survive. (1)

2.2 In South African grasslands, cattle are often found as grazers. A very large flock of cattle was introduced into an area of ungrazed grassland. Explain what their effect would be on the biodiversity within this area.

Question 3

FAIRBANKS, Alaska — Scientists have been monitoring the release of CO2 and methane from tundra in Alaska. A recent estimate suggests that the perennially frozen ground is melting, releasing large amounts of these gases.

3.1 Provide two characteristics of the tundra biome. (2)

3.2 What is the name given to permanently frozen ground in the tundra? (1)

3.3 Much of the organic matter in the frozen layer does not decompose normally. Explain why there is so much undecomposed organic matter in the frozen ground in the tundra. (1)

3.4 Why is there so much carbon dioxide and methane released after this ground melts? (2)

3.5 What is the effect of releasing methane and carbon dioxide into the atmosphere? (1)

Question 4

In the Arctic, snowy owls are predators of lemmings. The lemmings eat arctic plants.

The graph below shows the changes in the populations of snowy owls and lemmings over a three-year period.

4.1 During the first 10 months of year 1, the lemming population increases slowly at first and then more rapidly. Suggest why the rate of increase becomes greater. (1)

4.2 Using information in the graph, suggest why the lemming population falls during year 2. (1)

4.3 Using information in the graph, describe and explain how changes in the lemming population affect the snowy owl population. (3)

4.4 If all the snowy owls were removed from the arctic ecosystem, suggest and explain what effect this would have on the lemming population in the following years. (3)

4.5 Lemmings and snowy owls get their energy from the food they eat.

(a) What is the original source of all the energy in this ecosystem? (1)

(b) Name the process that first traps this energy. (1)

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Links

Clear Diagram and Summary:

http://cnx.org/contents/fe5ee9f2-7357-4d82-8fc3-44da2ac322e8@1