Transcript reindeer cycle

Starter activity-What is an ecosystem?
What do you already know…..
THINK
1.
PAIR
SHARE
A community of plants and animals and the environment
they live in.
Key question
What is an ecosystem?
Today we are learning to….
 Identify and define key terms.
 Name and locate world
ecosystems.
 Suggest characteristics of each
ecosystem
Group reading for meaning
 Give each person a
number on the table
from 1-4
 Each person needs to
take it in turns to read
paragraphs 1-4 from
the book extract
 As a group identify
which words you feel
will be the key terms for
this lesson and write
them
on
your
whiteboard
Group reading for meaning
An ecosystem is a community of plants and animals (the living environment) which
interact with each other and their non-living environment (soil, rock, air etc). The
type of plants and animals that live there depend upon the climate , soil, rock type and
relief (shape of the land). All parts of the ecosystem are closely interlinked and if one
part changes it will greatly impact on the rest.
Ecosystems can vary enormously in scale. They range from small ponds and
hedgerows to whole rainforests stretching thousands of kilometres across continents.
A very large ecosystem such as a rainforest is called a biome. The vegetation in a
biome is largely determined by climatic factors such as temperature, rainfall, sunshine
and wind.
When ecosystems are not touched by humans that are said to be natural
environments but in recent times ecosystems have been increasingly altered and even
destroyed by human activity. In Brazil, for example, 40% of the original rainforest has
been cleared for development, whilst across Scandinavia huge areas of coniferous
forest are slowly dying from air pollution called acid rain.
Many people are worried that changes brought about by human activity are
irreversible and will cause severe problems in the future.
Definition relay……
 Using your numbers 1-4
each person needs to take it
in turns to find the correct
definition, to remember it
and to relay it to your team.
 Match the definition with
the term
Key terms and definitions-Check your
answers and write them into your books.
Environment
This is the interaction of plants and animals
with their non-living environment.
Non-living environment This includes examples such as rocks, soil, the
air and the climate.
Living environment
This includes examples such as animals, birds,
fish, insects and people.
Ecosystem
This is the natural or physical environment
where plants and animals live.
Natural ecosystem
This is a community of plants and animals
unaffected by human activity.
Biome
This is a large ecosystem such as a tropical
rainforest or a desert.
This is the interaction of plants and animals with their
non-living environment.
This includes examples such as rocks, soil, the air and
the climate.
This includes examples such as animals, birds, fish,
insects and people.
This is the natural or physical environment where
plants and animals live.
This is a community of plants and animals unaffected
by human activity.
This is a large ecosystem such as a tropical rainforest
or a desert.
Major
world
biomes
 Work as a team
to look
carefully
through your
pack of cards.
 Work out
which cards are
useful and
which ones are
misleading you.
 Locate your
accurate cards
onto the global
map.
Major
world
biomes
 Which biomes
have you not
got an example
for?
 Use the key to
help you figure
it out.
 Work as a
group to give
an example of
the location of
missing biomes
What are the characteristics of the worlds ecosystems?
What is a characteristic?
This is a feature
belonging to a
place that helps
to identify them
What are the characteristics of the worlds
ecosystems?
 There are 8 different ecosystems across the
globe. Your teacher will give you a number
that will determine your ecosystem.
 You will take responsibility for the 4
characteristics of your ecosystem.
1=Name your
ecosystem.
2=Describe the
climate.
3=Describe the
soil type.
4=Describe the
animals
5=Describe the
vegetation
Hexagon learning
5
5
4
4
3
3
2
2
1
1
Characteristics
of the
ecosystems
1
2
3
4
5
1
2
3
4
5
=What do you
think is the key
link that
determines
these
ecosystems
The tropical rainforest is a biome with a constant temperature and a high rainfall. The level of humidity and density of
the vegetation give the ecosystem a unique water and nutrient cycle. Rainforests around the world are threatened by
human expansion.
Characteristics and climate
A tropical rainforest biome is found in hot, humid environments in equatorial climates. They contain the most diverse
range and highest volume of plant and animal life found anywhere on earth. In general, tropical rainforests have hot and
humid climates where it rains virtually everyday. The level of rainfall depends on the time of year. Temperatures vary
through the year - but much less than the rainfall.
The graph shows average rainfall and temperature in Manaus, Brazil, in the Amazon rainforest. The rainy season is from
December to May. Notice how much the rainfall varies over the year - the highest monthly rainfall is in March with over
300mm, while the lowest is in August with less than 50mm. Over the year, the temperature only varies by 2°C.
Rainforest ecosystems are characterised by heavy convectional rainfall, high humidity, lushness of vegetation and nutrientrich but shallow soil.
Rainforest water cycle
The roots of plants take up water from the ground and the rain is intercepted as it falls - much of it at the canopy level. As
the rainforest heats up, the water evaporates into the atmosphere and forms clouds to make the next day's rain. This is
convectional rainfall.
Rainforest nutrient cycle
The rainforest nutrient cycling is rapid. The hot, damp conditions on the forest floor allow for the rapid decomposition of
dead plant material. This provides plentiful nutrients that are easily absorbed by plant roots. However, as these nutrients
are in high demand from the rainforest's many fast-growing plants, they do not remain in the soil for long and stay close to
the surface of the soil. If vegetation is removed, the soils quickly become infertile and vulnerable to erosion.
If the rainforest is cleared for agriculture it will not make very good farmland, as the soil will not be rich in nutrients.
Rainforest soils
Soils are red due to the high iron and aluminium content. There is a thick layer of leaf litter and decomposing organic
matter on the surface
Tropical rainforests have dense vegetation. From ground level up these levels of vegetation are:
The shrub layer. It is dark and gloomy with very little vegetation between the trees. During heavy rainfalls this area can
flood.
The under canopy is the second level up. There is limited sunlight. Saplings wait here for larger plants and trees to die,
leaving a gap in the canopy which they can grow into. Woody climbers called lianas avoid having to wait for gaps by
rooting in the ground and climbing up trees to get to the sunlight.
The canopy is where the upper parts of most of the trees are found. The canopy is typically about 65 to 130 feet (20 to 40
metres) tall. This leafy environment is home to insects, arachnids, birds and some mammals.
emergents are the tops of the tallest trees in the rainforest. These are much higher, and so are able to get more light than
the average trees in the forest canopy.
CONIFEROUS FOREST
Coniferous or boreal forests occur in cold northern regions characterised by long cold winters and
short summers. Although there is a lot of precipitation, most of it falls as snow.
This biome is found between 50° and 60° north of the equator and is characterised by evergreen
coniferous trees with needles instead of leaves. It is also known as Taiga.
Typical trees include spruce, pine and fir. Animals commonly found in the region are reindeer, voles
and hares.
At the most northern extent, summer temperatures rarely rise above 10°C. As you move further
north, trees are shorter and less dense because of the shorter growing season. Winter temperatures
can fall as low as minus 30°C. At its southern margins, the trees become taller and denser and merge
with deciduous trees (those that lose their leaves). Temperatures here can rise as high as 20°C in the
summer and can fall to minus 15°C in winter. Precipitation is 300–900 mm, and most falls as snow in
winter.
Coniferous trees have thick bark to protect against the cold. They are cone-shaped, with flexible
branches which help them to cope with heavy snow fall.
Pine cones protect the seeds during the harsh winter.
The thin waxy needles reduce water loss.
Their evergreen nature means that the needles can photosynthesize whenever there is sufficient
sunlight.
The dense forest creates warmth during the harsh winter.
Taiga soils
Soils are shallow due to lack of decomposition and weathering caused by the cold. They are acidic
due to leaching from rainfall and they are also poor in nutrients.
The litter layer is thick with needles due to slow decomposition.
The humus (decomposed) layer is thin.
There are clear boundaries between the layers in the soil as there are few worms to mix it in the cold
conditions.
Trees have shallow roots.
The typical soil is a podsol, which has a distinctive ash grey layer (or horizon) above a red layer, which
is rich in iron.
DECIDUOUS FOREST
Deciduous woodlands contain trees with broad leaves such as oak, beech and
elm. They occur in places with high rainfall, warm summers and cooler winters
and lose their leaves in winter.
Characteristics and climate
Temperate deciduous forests are found between 40° and 60° north and south
of the equator.
See where deciduous forests are found across the world on this biomes map.
The rainfall is high, between 500-1,500 mm a year. The temperatures remain
on average above 0°C even in the winter. The summer temperatures average
between 25-20°C. The winter is cooler, encouraging the trees to shed their
leaves.
The trees have typically large broad leaves, such as oak, beech and elm. These
form the canopy layer.
As some light can get through, the vegetation is layered. Beneath the taller
trees is a shrub layer. The shrub layer contains species like hazel, ash and holly.
Grass, bracken or bluebells can be found in the ground layer.
Soils in deciduous woodland
The soil type is brown earth. This is a fertile soil. In the autumn the leaves fall
from the trees. The leaves decompose and help to give the soil its nutrients.
Earthworms in the soil help to mix the nutrients, and blend the layers within
the soil.
The tree roots are deep and so help to break up the rock below. This helps to
give the soil more minerals. The trees take up the nutrients in the soil as they
grow. However, more nutrients are put back in the soil when the autumn comes
SAVANNAH GRASSLAND
The savannah biome is located further away from the equator than the tropical rainforest biome in the
central part of Africa and in South America. It is dry, but not as dry as desert areas.
Savannahs - also known as tropical grasslands - are found to the north and south of tropical rainforest
biomes. The largest expanses of savannah are in Africa, where much of the central part of the continent,
for example Kenya and Tanzania, consists of tropical grassland. Savannah grasslands can also be found in
Brazil in South America.
Savannah regions have two distinct seasons - a wet season and a dry season. There is very little rain in
the dry season. In the wet season vegetation grows, including lush green grasses and wooded areas. As
you move further away from the equator and its heavy rainfall, the grassland becomes drier and drier particularly in the dry season. Savannah vegetation includes scrub grasses and occasional trees, which
grow near water holes, seasonal rivers or aquifers.
Plants and animals have to adapt to the long dry periods. Many plants are xerophytic - for example, the
acacia tree with its small, waxy leaves and thorns. Plants may also store water, for example the baobab
tree) or have long roots that reach down to the water table. Animals may migrate great distances in
search of food and water.
The graph below shows average monthly temperatures and rainfall levels in the savannah region of Mali.
Notice how the temperature and rainfall patterns relate to each other - the hottest temperatures come
just before heavy rainfall, and the coolest time of the year comes just after the rains. This pattern is
typical of savannah climates.
Savannah grassland soils are not very fertile. The nutrients in the soil are found near the surface as they
come from decayed organic matter (vegetation) from the previous growing season. This organic matter
decays rapidly due to the high temperatures.
Soils tend to be red in colour due to their high iron content. The diagram below shows the different
horizons, or layers, of soil in savannah grassland. Plant roots cannot penetrate the hard 'pan' layer in the
B-horizon, or subsoil. This restricts vegetation growth.
The Serengeti
Map showing location of the Serengeti
The Serengeti plains of Tanzania are probably the best known African savannah.
There are two main types of vegetation in the Serengeti. Grasses cover the vast open plains of the
southeast while in the central region, acacia plants are more common. The Serengeti is rich in wildlife including giraffes, zebras, elephants, lions and over 2 million wildebeest. Many of the animals found on
the Serengeti can be found nowhere else in the world.
Tundra biomes are cold and treeless with very little precipitation. The landscape
is quite bare with vegetation specially adapted to the low temperatures.
Tundra areas include Northern parts of Canada, Russia and Alaska.
The temperatures stay below 0°C most of the year. The ground remains frozen,
apart from a few centimetres of thaw in the summer. The precipitation is gentle,
mainly falling as snow. The winds can be very strong. Summers may have many
hours of continuous daylight. Winters are long, dark periods. The climatic
conditions mean that the landscape is quite bare, with little vegetation.
TUNDRA
Vegetation adaptation
Tundra pond with cotton grass growing nearby, Arctic National Wildlife Refuge,
Alaska
Vegetation needs to be able to tolerate cold. Very few species are able to do this.
Plants are low growing, compact and rounded in order to help protect from the
wind. The frozen ground means soils are waterlogged.
Cotton grass is one example of a plant able to survive these conditions. The
features which make it able to survive are:
low-lying - the snow covers it in winter which helps insulate it
seeds that scatter in the wind narrow leaves helping to reduce transpiration
adapted to a short growing season (so has a short life cycle) dense flowerheads
reducing heat loss darker leaves helps absorb energy from Sun.
DESERT
Deserts are hot during the day and cold at night. Animals and plants that live
in deserts have adapted to survive in these harsh conditions.
Characteristics and climate of deserts
Deserts have extreme temperatures. During the day the temperature may reach
50°C, when at night it may fall to below 0°C. Deserts have less than 250 mm of
rainfall per year. The rain can be unreliable. Most deserts are found between
20° and 35° north and south of the equator.
The Sahara is the largest desert, covering 9 million km2.
There are three factors which form desert areas:
the presence of high pressure, creating cloud-free conditions; cold ocean
currents; mountain ranges to create rain shadows.
Plants and animals need to cope with the dry conditions. Compared to other
biomes, deserts have limited numbers of plants and animals that are able to
survive.
Some plants are succulents and store the water in leaves, stems or roots. One
example is the cactus. Other ways plants tolerate the dry conditions include:
long roots to tap into the water deep underground
short life cycles - a plant or seed could remain dormant until the rains come
Animal survival
Some may burrow to escape the heat.
Nocturnal animals sleep during the day, sheltering to help prevent dehydration.
Animals may hibernate during temperature highs or lows
MEDITERRANEAN
Mediterranean ecosystems are limited to five relatively small areas
around the planet: the region bordering the Mediterranean Sea, central
Chile, the Cape region of South Africa, southwestern and southern
Australia, and California south to northern Baja California. These
ecosystems largely occur along the western edges of continents
between the 30° and 40° parallels in both northern and southern
hemispheres. The climate, moderated by cold ocean currents offshore,
is characterized by hot, dry summers and mild, wet winters.
Throughout the world, the Mediterranean climate region is
characterized by evergreen or drought deciduous shrublands. The
chaparral of southern California is echoed in the old world
Mediterranen maquis, the Chilean matorral, South African fynbos and
the Australian mallee scrub communities. Due to the limited extent
(covering only 2.2 percent of Earth’s land surface) and isolation (almost
island-like) of the Mediterranean climate region, there is an
extraordinary high biodiversity of uniquely adapted animal and plant
species.
The Mediterranean climate region have been highly favored and
impacted by humans for habitation, agriculture and recreation and as a
result, are one of the most highly altered on the planet and contain the
least amount of undisturbed area of any ecosystem.
MOUNTAIN
Mountain lands provide a scattered but diverse array of habitats in
which a large range of plants and animals can be found. At higher
altitudes harsh environmental conditions generally prevail, and a
treeless alpine vegetation, upon which the present account is
focused, is supported. Lower slopes commonly are covered by
montane forests. At even lower levels mountain lands grade into
other types of landform and vegetation—e.g., tropical or temperate
forest, savanna, scrubland, desert, or tundra.
Characteristics of world biomes
Climate
Tropical
Rainforest
Savannah
Grassland
Tundra
Mountains
Desert
Mediterranean
Coniferous
Forest
Deciduous
Forest
Soil
Animals
Vegetation
Environment
This is the interaction of plants and animals
with their non-living environment.
Environment
This is the interaction of plants and animals
with their non-living environment.
Non-living
environment
This includes examples such as rocks, soil,
the air and the climate.
Non-living
environment
This includes examples such as rocks, soil,
the air and the climate.
Living
environment
This includes examples such as animals,
birds, fish, insects and people.
Living
environment
This includes examples such as animals,
birds, fish, insects and people.
Ecosystem
This is the natural or physical environment
where plants and animals live.
Ecosystem
This is the natural or physical environment
where plants and animals live.
Natural
ecosystem
This is a community of plants and animals
unaffected by human activity.
Natural
ecosystem
This is a community of plants and animals
unaffected by human activity.
Biome
This is a large ecosystem such as a tropical
rainforest or a desert.
Biome
This is a large ecosystem such as a tropical
rainforest or a desert.
Environment
This is the interaction of plants and animals
with their non-living environment.
Environment
This is the interaction of plants and animals
with their non-living environment.
Non-living
environment
This includes examples such as rocks, soil,
the air and the climate.
Non-living
environment
This includes examples such as rocks, soil,
the air and the climate.
Living
environment
This includes examples such as animals,
birds, fish, insects and people.
Living
environment
This includes examples such as animals,
birds, fish, insects and people.
Ecosystem
This is the natural or physical environment
where plants and animals live.
Ecosystem
This is the natural or physical environment
where plants and animals live.
Natural
ecosystem
This is a community of plants and animals
unaffected by human activity.
Natural
ecosystem
This is a community of plants and animals
unaffected by human activity.
Biome
This is a large ecosystem such as a tropical
rainforest or a desert.
Biome
This is a large ecosystem such as a tropical
rainforest or a desert.
Mediterranean-Russia
Grassland -England
Mountains-Australia