ecological relationships and energy flow -...
TRANSCRIPT
Ecologyis the study
of living thingsin their environment
Ecosystem =
community + environment(all the living things) (all the surroundings)
What is an
Ecosystem?
An ecosystem is the name given to all the living things, community, and their non-living environment in a particular area.
The living organisms are all dependent on each other through feeding relationships.
How does life on Earth rely on energy from the Sun?
Energy flow• Life can exist on Earth
because of sunlight energy.
• Plants capture light energy through the process of photosynthesis.
• And make organic compounds such as carbohydrates
• Energy is transferred through the ecosystem by feeding relationships.
Finding out about populations in a habitat
Fieldwork provides information about what plants and animals live in a particular habitat and their numbers.
It is therefore necessary
• to be able to identify organisms, using keys
• and understand the different sampling
techniques used to count them.
We cannot actually count every plant or animal in a
particular place, so
we count a sample of the population to calculate
an estimated population size.
Sampling populations
You should understand the importance of random sampling.
This is essential to avoid observer bias.
WHAT DOES THIS MEAN?This means that the person collecting the data does not affect the result deliberately, e.g. by only counting in one area.
Quadrats are usually used
to count plants,
but can also be used
to count slow moving
animals
such as snails.
1. Lay out two tapes at right-angles in the area you
want to sample.
2. Use random number tables to pick co-ordinates:
• quadrats should be placed randomly so that a
representative sample is taken.
3. Place a quadrat (of suitable size) at that point and
count the organisms within it.
4. Repeat using using at least 20 quadrats, at other
random coordinates across the grid:
• repeating increases the reliability.
• collecting across the whole grid area reduces the
effect of an unusual distribution
5. Calculate the average number of organisms in each
quadrat
6. Use the average to calculate an estimated total
number of organisms in the grid area.
Quadrats can be used to estimate a population in an area which is fairly uniform. Examples include lawns, woods and open ground.
There are three ways to count organisms to estimate population size:
• 1. Density
(calculating the number of organisms per m2);
• 2. Frequency
(number of quadrats that contain the organism)
• 3. Percentage cover
(estimating the percentage of the grid area that contains the organism)
Percentage cover – do you agree with the estimates?
• Percentage cover is an easy way to estimate population size.
• However, a disadvantage is that it is difficult to estimate exactly what percentage of the quadrat is actually covered by a particular type of plant, so it is normal to round up to the nearest 10%. An exception is if there are any plants with a percentage cover of 1 -5% -this is recorded as 1 and not 0.
• This makes the results less reliable than estimating the density.
Belt transects can be used to
investigate
changes in the distribution
of organisms along a
particular habitat,
e.g. due to changing abiotic
factors such as light intensity
Sampling animal populations
How do we know that the invasive
harlequin ladybird is affecting the
populations of native ladybirds?
used to collect small
invertebrates.
• Sweep nets allow you to collect large numbers of invertebrates that live in low vegetation (stems, tall grasses, flowers etc) or in rivers and ponds
• Sweep netting involves making a large rapid sweep with a net in between large paces.
• The invertebrates can be collected in a tray and counted
Stones to prevent rain flooding the trap or birds or other
predators from removing the trapped animals
jar sunk in a hole in the ground
Pitfall traps must be properly set up:
• the top of the jar should be level with the soil surface
• cover the trap with a stone or piece of wood to keep out the rain, to make it dark and to stop birds eating your catch
• the traps must be checked often to avoid the animals escaping or being eaten before they are counted
• as with most methods a large number of traps makes results more reliable and minimises the effects of unusual results
• http://www.bbc.co.uk/scotland/learning/bitesize/standard/biology/biosphere/investigating_an_ecosystem_rev5.shtml
These are the non-living, physical parts of the environment, including:
• Wind
• Water
• pH
• Light
• Temperature
These are the living parts of the environment, including:
• Predators
• Disease
• Waste produced by living organisms
See worksheet (pages 54 -55 textbook)
Each organism is adapted (suited) to the environment in which it lives.
This case study tries to explain why specific plants live at different distances from the seashore.
1. Describe the area that was being studied.
2. What sampling method was used to study the distribution of plants along the sand dunes?
3. How many samples were taken?
• 1km sand dune, divided into 3 sections.
• Section 1 from the start of the first sand dune inshore.
• Section 2 half way between 1 and 3.
• Section 3 from the end of the last dune to to the start of the woodland.
• 3 interrupted belt transects
• 20 at each site
4. Name the biotic data collected.
5. Name the abiotic data collected
• the average percentage cover
• of marram grass, common heather and gorse
• along each transect
• average light intensity reaching the ground
• Average soil moisture
• Average pH
6. Describe the conditions in which each of the plants prefers to grow.
• Marram grass: can grow in very unstable conditions such as those found near the shore, where the sand is constantly moving in the wind. It helps to stabilise the dunes, by holding the sand together for other plants to grow in.
• Heather: small shrub, prefers stable moist soil
• Gorse: large shrub, prefers very stable soil with lots of moisture and nutrients
7. Describe the trends shown by the graphs.
• Marram grass is only common in transect 1
• Heather is not found in transect 1 but is found in transect 2
• Gorse is most common in transect 3, but uncommon or absent at transects 1 and 2.
8. Use the biological knowledge about the 3 plants and the abiotic data to explain the trends.
• Marram grass can grow at the beginning of the dunes where there is not much water available in the sand, 20%.
• It needs high light intensity to grow, 95%.
• Further inland, where the conditions are more stable, there is less light and there is more moisture, so the other plants out-compete the marram grass.
• Heather cannot grow in transect 1 because there is not enough moisture.
• Gorse grows best in transect 3 where there is most water, 60%.
• Gorse is a large shrub and creates shade, preventing the marram grass and heather from growing.
9. What features of this investigation make the results reliable?
10. How could the reliability be increased further?
• The plants were counted in 20 quadrats at each transect and an average was calculated.
• ******
11. Explain why you think this a fair test?
12. State the following:
the independent variable
the dependent variable
the controlled variables
• Only one thing was being changed.
• The position of the transect along the dune.
• Percentage plant cover in each quadrat
• Size of the quadrat
• Time of the year the measurements were taken.
It was not possible to keep the wind, light intensity, soil moisture or pH controlled. However these factors were measured and helped to explain the presence or absence of the plants at the different transects.
• Keys are used to identify unknown organisms. Dichotomous keys, used in biology, consist of a series of two part statements that describe observable features of organisms.
• At each step of a dichotomous key you are presented with two choices. As you make a choice about a particular feature or characteristic of an organism you are led to a new branch of the key. Eventually you will be led to the name of the organism that you are trying to identify.
Constructing a key for objects in a pencil case
1. Look at the group of objects and separate them into two groupsbased on a single observable feature.
2. Look at each group separately and again separate each into two groups based on a single observable feature.
3. Continue until each group has only one object.
A dichotomous key may be shown as a branching diagram or as a numbered key.
A branching key:
A numbered key:
• Carefully examine and think about the observable features of the 8 aliens and create a dichotomous key using some of these characteristics.
Broad leaved trees
This trees leaves are green all over and have a hairy upper surface. They are rounded with a pointed tip and they are larger on one side of the midrib than the other. The edges of the leaves are toothed, but they have no lobes or prickles. The stalk is short and rounded and bears a single leaf.
LEAF LITTER
This wingless invertebrate has a waistless segmented body with 3 pairs of legs. It uses a spring under its abdomen to move by jumping.
Grassland
This 6 legged invertebrate has a broad body with a triangle shape on its back. It has 2 pairs of wings; one pair forms a protective case. It moves by flying or walking and has no obvious snout.
Garden weeds
This spineless weed has smooth edged, arrow shaped leaves. The stem trails along the ground and produces pink and white trumpet shaped flowers.
All living organisms are divided into five large groups called Kingdoms.
The 5 kingdoms are:
All the organisms in each kingdom have specific features in common.
These include:
(1) their mode of nutrition (how they feed)
(2) whether they have a cell wall
(3) cellular organisation;
Group Nutrition Cell wall Cellular organisation
Protoctista Saprophytic or photosynthetic
Cellulose cell wall or none
Single celled with nucleus or algae that are not truly multicellular
Bacteria Saprophytic Non-cellulose Single celled with no nucleus
Fungi Saprophytic or parasitic
Non-cellulose Single or multicellular –can be ‘acellular’ with it being difficult to distinguish individual cells and nuclei scattered throughout the organism
Plants Photosynthesis Cellulose Single or multicellular –‘typical’ cell arrangement with a nucleus
Animals Eating organic food None Single or multicellular –‘typical’ cell arrangement with a nucleus
fungal cell
dead food
1. Enzymes released
onto food
2. Enzymes digest food
3. Soluble
products
absorbed
1. Some organisms are difficult to classify e.g. Euglena, which has both plant and animal characteristics. This is why single-celled plants and animals are classified in a separate group called the Protoctista.
2. Sometimes it is difficult to identify which species an organism belongs to or where one species merges into another. Definition – a species is a group of organisms, with shared features, which can breed together to form fertile offspring.
3. Viruses are a complex group and are very difficult to classify. All viruses, e.g. the HIV virus that causes AIDS, lack proper cellular organisation. They have a DNA/RNA core (DNA and RNA are nucleic acids – the building blocks of chromosomes) and an outer protein coat without the typical cytoplasm of other cells. They can only live if they gain access to other cells and many biologists therefore regard them as non-living.
Read through your notes on classification before answering
question 3 (p71) in the
GCSE Biology textbook.
Ecological terms
biodiversity, population, habitat, environment, community and ecosystem
Match the terms with the definitions and write them into your notes.
[Answers on next slide ]
TERM DEFINITION
Biodiversity A measure of the number of different types of plant and animal species in an area
Population The number of one type of organism (species) in an area
Habitat The place where an organism lives
Environment The factors, both physical (abiotic) and living (biotic), that affect organisms in a habitat
Community The total number of organisms from all the populations in an area
Ecosystem The community of organisms that are interdependent on each other and the environment in which they live
Population numbers change over time.
Many factors can contribute to population change but they can be summarised by:
Population changes
•Birth rate
•Death rate
•Immigration
•Emigration
This can be written as an equation:
Population growth =
(birth rate + immigration) – (death rate + emigration)
The Sun as Energy Source
The Sun is the energy source for most ecosystems.
Green plants play a vital role as ‘producers’ in capturing this energy through the process of photosynthesis.
The plants make sugars and other organic compounds that are then eaten by other organisms, so:
plants make the sunlight
energy available to other
organisms.
The sequence of producers trapping the Sun’s energy and this energy then passing on to other organisms as they feed is known as
energy flow.
The different stages in the feeding sequence are called trophic levels (or
‘feeding levels’).
The sequence can be drawn as arrowsfrom producer to consumers, the arrows
representing energy flow.
The sequence of energy flow from producer to consumers is known as a
food chain.
In all food chains the first organism (at trophic level 1) is the producer (a plant) and it provides food and energy for primary consumers.
Note that in reality very few animals have only one food source, so energy flow in an ecosystem is more accurately represented by a food web, not a simple chain.
Food webs show how a number of food chains are interlinked and they give a more realistic picture of feeding relationships.
Energy loss & trophic levels
Most food chains are relatively short, with just four organisms.
This is because at each stage of energy transfer (including trophic level 1), some energy is lost.
Not all of the energy from the Sun is trapped by producers. This is because:
• light is reflected from leaves
• light passes through leaves and misses chloroplasts
• light energy is used to evaporate water from leaves.
trophic level 1
The transfer of energy between plants and animals and between animals of different trophic levels is usually 10 – 20%.
This means that for every 100g of plant material available, only between 10 and 20g is built up as a tissue (as ‘biomass’) in the primary consumer’s body. The same applies when secondary consumers eat primary consumers.
trophic levelS 2 ETC
The loss of energy between plants and consumers and between consumers is due to
three main reasons:1. Not all the available food is eaten. Most carnivores
do not eat the skeleton or fur of their prey, for example.
2. Not all the food is digested; some is lost as faeces in egestion.
3. A lot of energy is lost as heat in respiration. Respiration provides the energy for movement, growth, reproduction etc. Heat is produced as a by-product of respiration. Heat is lost and cannot be passed on to the next trophic level.
SUN
PRODUCER
PRIMARY
CONSUMERSECONDARY
CONSUMER
DECOMPOSERS
Energy Flow
& excretion
& undigested material
including heat
& movement
15
316
1890
11,977
6
x
1095
5465
respir
ation
decay
TOTAL = 6612 kJ TOTAL =
What would happen if a disease killed
all of the snakes?
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What effect would there be if the, due to
poor spring weather, the rowan flowers
were not fertilised?
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Pyramids of number and biomass
• The number of organisms at each stage of a food chain (i.e. at each trophic level) can be represented by a pyramid of numbers.
• Each bar represents a trophic level and is drawn the same height.
• The width of the bar represents the number of organisms at that trophic level.
The problem with a pyramid of numbers is that it is not always pyramid-shaped, as it does not take into account the size of the organisms involved, e.g. one oak tree will support many more organisms than one grass plant
Pyramids of numbers that include parasites may also appear top heavy, as many parasites will feed on one consumer.
Advantages/disadvantages
Advantages of pyramid of numbers Disadvantages of pyramid of numbers
Easy to count Ignores sizes of organisms
No organisms get killed Difficult to convert e.g. grass plant leaves to numbers which can be worth comparing with others
When representing energy flow through a food chain it is sometimes more accurate to use a pyramid of biomass.
These diagrams represent
the mass of living tissue
in the organisms.
Advantages/disadvantages of pyramids of biomass
Advantages of pyramid of biomass Disadvantage of pyramid of biomass
Amount of energy in a trophic level more accurately represented
Organisms must be collected and killed in order to measure biomass (usually dry weight of organisms).
Difficult to catch/weigh all organisms
The biomass of an individual can vary through the year, e.g. an oak tree will have a much greater biomass in June than in December
Another difficulty in producing both pyramids of number and biomass arises if organisms feed at two different trophic levels e.g. an organism that eats both plants and animals.
Review
Complete questions 1, 2 and 4 from GCSE textbook p70 – 71
[Note that this may take up to 30 minutes]
http://www.bbc.co.uk/bitesize/ks3/science/organisms_behaviour_health/food_
chains/revision/8/
http://www.bbc.co.uk/bitesize/ks3/science/organisms_behaviour_health/food_
chains/revision/9/
http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel_pre_2011/enviro
nment/populationsandpyramidsrev2.shtml
Decomposition
What happens to the energy available in dead organisms? Decomposers break down dead organisms-plants and animals. Decomposers are important to an ecosystem because they return nutrients to the environment.
Bacteria and fungi are examples
of decomposers – they are
saprophytes.
Decomposing action of saprophytic fungi and bacteria
• A saprophyte is an organism that feeds on dead or decaying organic matter. Saprophytic bacteria and fungi secrete enzymes into the soil or dead organism. The enzymes break down (digest) the organic material and then it is absorbed by the bacteria or fungi. This is known as extracellular digestion.
Extracellular digestion – a reminder
Formation of humus
Humus is the organic content of the soil formed from decomposing plant and animal material. Decomposition takes place more quickly when conditions are optimum. These include:
A warm temperature
Adequate moisture
A large surface area in the decomposing organism.
Give two reasons why large, flat tropical plant leaves will decompose much more quickly than Norwegian pine needles.
Nutrient cycles
The flow of nutrients in ecosystems differs from the flow of energy in important ways. In a stable ecosystem the overall gain or loss of nutrients from the system will be small and, unlike energy, the nutrients can be recycled as part of a nutrient cycle.
Remember that decomposers can break down organic compounds, and nutrient cycling involves the processes of decay and decomposition.
For recycling to take place, dead organisms must first be broken down during the decay process.
Organisms involved in this process include earthworms, woodlice and various types of insect – these organisms are known as ‘detrivores’.
Fungi and bacteria are the decomposers that break down the organic compounds into their simplest components.
• The decomposing action of saprophytic fungi and bacteria also helps in the formation of humus, the organic substance in soil that makes it more fertile and produces good ‘crumb structure’.
• Recall the previous notes made on the formation of humus that included the key features of the decay process - a warm temperature, adequate moisture and a large surface area in the decomposing organism.
Carbon cycle
Carbon is found in all organic molecules, including glucose, starch, cellulose, glycogen, fats and proteins.
It is also found in inorganic compounds such as carbon dioxide and the carbon compounds in coal, oil and gas.
contains the
carbon compound
take in carbon dioxide from the air
and make
carbon containing compounds eg
Eat plants and other animals and make
carbon containing compounds eg
Feed on dead plants and animals and
release
when they respire
contain
carbon compounds eg
They release carbon dioxide during
combustion
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Design a Carbon Cycle poster
Using diagrams from GCSE textbooks and the key terms from matching activity, create a poster on the carbon cycle that includes an annotated diagram.
The Carbon Cycle and Global Warming
Carbon dioxide gas is one of the gases present in the Earth’s atmosphere. It has been present for millions of years, but recent evidence has shown that the level of carbon dioxide in the atmosphere is rising. There is also evidence that humans are responsible for the increase in carbon dioxide levels.
Two main changes have contributed to the rise in carbon dioxide levels and therefore carbon cycling on Earth:
1. Increased combustion of fossil fuels has added more carbon dioxide to the atmosphere;
2. Increased deforestation has removed many forests, meaning that less carbon dioxide is taken out of the atmosphere by the process of photosynthesis.
The changes mean that the carbon cycle has become unbalanced.
The link between carbon dioxide levels and global warming
The atmosphere that surrounds the Earth acts as an insulator – trapping heat from the Sun’s radiation to produce a temperature suitable for life on our planet. Without carbon dioxide and water vapour, the surface of the Earth would be at -40oC. The ‘greenhouse effect’ is necessary for life as we know it, but the problem in recent years has been an increase in the concentration of gases that contribute to the greenhouse effect.
Increasing carbon dioxide levels
However, some gases add to this ‘greenhouse effect’ more than others, for example carbon dioxide, methane and water vapour. It is thought that the increase in carbon dioxide due to human activity is in turn increasing the greenhouse effect, that is, an enhancedgreenhouse effect. The enhanced effect is leading to ‘global warming’.
Evidence for global warming
Scientists have been highlighting the increase in carbon dioxide levels for many years and have been attempting to persuade Governments to take global warming seriously. It is only recently that many politicians and people have accepted that it is the increase in carbon dioxide levels that are causing global warming.
It is difficult for some nations to accept the link because that also means accepting that human beings are responsible and that we must change our lifestyle to try to reduce our dependence on fossil fuels.
Effects of global warming
The warming of the atmosphere causes:
• Climate change – more weather extremes such as droughts and severe storms;
• Polar ice-caps to melt;
• Increased flooding;
• More land to become desert.
Reducing global warming
Explain in your own words how the following actions could reduce global warming:
Planting more trees
Reducing deforestation
Burning less fossil fuels by using alternative fuels and/or becoming more energy efficient.
Reducing carbon emissions
• Agenda 21 is an action plan of the United Nations (UN) related to promoting sustainable development and was an outcome of a conference on the environment held in Rio de Janeiro, Brazil, in 1992. It is a recommendation for action to be taken globally, nationally, and locally by organizations of the UN, governments, and major groups in every area in which humans directly affect the environment.
North Down Borough Council
Scientific evidence of human effects on the environmentinforms our local government about the need to implement policies such as:
- Reductions in carbon emissions;
- Increases in renewable energy; and
- Changes in agricultural practices (see later notes following eutrophication).
[Read information sheet ‘Local Agenda 21 in North Down’. From the information provided identify two questions you could ask environmental staff from NDBC regarding Council policies ]
Changes brought about by local councils in recent years include providing ‘brown bins’ to households to increase composting and ‘blue bins’ for recycling paper, some plastics and metal cans.
The recycling Centre at Balloo has a wind turbine.
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• live in the soil
• and in the root nodules
of leguminous plants
Clover plant
• convert nitrogen gas in air
into nitrates
• root hair cells of plants
take up nitrates
• from an area of
low concentration
in the soil
• to an area of
higher concentration
in cells
• using energy
from respiration
• animals eat plants
• they convert nitrogen containing amino
acids into proteins for growth
• feed on dead organisms
• & waste material
• convert nitrogen
containing compounds
e.g. proteins & amino acids
into ammonia
• live in the soil
• convert ammonia
into nitrates
• removes plants from the area
• nitrogen compounds not returned to the soil
• artificial fertiliser
made in factories
• contains ammonia
and nitrates
• added to the soil to
replace nitrogen
compounds removed
in harvesting
• live in waterlogged soil (flooding)
• in anaerobic conditions (compacted by
tractors)
• convert useful nitrates into atmospheric
nitrogen gas
• Why do gardeners
rotate their crops,
planting legumes
such as peas and
beans in an area
one year and
root vegetables,
potatoes or
cabbages in
the same area
the next year?
• Farmers put air into the soil when they plough their fields. This provides oxygen for aerobic
decomposers and
nitrifying bacteria and
speeds up decay
and nitrate formation.
It also provides oxygen
to root hair cells to speed
up respiration and active
uptake of nitrates.
Name two other ways in
which ploughing helps
crop growth.
• Proteins in plants and animals contain nitrogen.
• Name the substance that proteins are made of.
• Artificial fertilisers often contain compounds of ammonia.
Why is this useful?
The Nitrogen cycle
• Most of the nitrogen in plants and animals is in the form of amino acids and protein . The nitrogen cycle can be split into three phases:
1. The build-up of nitrogen into amino acids and protein in plants and animals and the eventual breakdown of these compounds into nitrates. Plants absorb nitrogen as nitrates and use them to make proteins . As plants (and animals) are eatenthe proteins are eaten, digested and then built up into other proteins in sequence.
Eventually the nitrogen is returned
to the ground as urine or through
the process of death and decay.
Decay or putrefying bacteria and fungi break down proteins to release ammonia. A second very important group of bacteria, nitrifying bacteria, convert the ammonia or ammonium compounds into nitrates (nitrification).
2. Nitrogen-fixing bacteria are a special group of bacteria that can convert nitrogen gas into nitrates. These bacteria can be found in the soil or frequently in small swellings (root nodules) in the roots of a group of plants called legumes.
• Legumes include peas, beans and clover. The relationship between the legumes and bacteria is beneficial for both organisms; the bacteria gain carbohydrates from the legumes and they in turn provide a source of nitrates for the plants. The process of converting nitrogen from the atmosphere into nitrates is called nitrogen fixation.
3. Denitrifying bacteria convert nitrates into atmospheric nitrogen. This is a wasteful and undesirable process.
Denitrifying bacteria are anaerobic and are most commonly found in waterlogged soils. Their effect in well-drained soils is much reduced. The process of converting nitrates into nitrogen is called denitrification ().
Consider: Why might ploughing a field be advantageous to a farmer growing crops?
Root hair cells and active uptake
Plants need nitrates to form proteins and they obtain these from the soil through root hair cells by active uptake.
The diagram of a root hair cell shows the adaptations of the cell:
• An extended shape (a ‘cytoplasmic extension’)
• Providing an increase in cell surface area for increased uptake of water and minerals.
Active uptake is a process that
requires energy to transport
minerals against a concentration
gradient.
This is because there are more nitrate ions inside the cell compared with outside in the soil. This process requires oxygen for aerobic respiration to produce the energy needed to transport the nitrates against the concentration gradient.
Review: what is meant by ‘concentration gradient’?
Replacing lost nitrogen – the use of fertilisers
When farmers harvest crops, or animals are taken to the abattoir, the nutrients they took from the soil are not replaced. The crops do not decay and decompose back into the soil to recycle the nutrients. For this reason, soil needs to be fertilised on a regular basis.
Important minerals
Calcium – needed for plant cell walls.
Magnesium – needed for chlorophyll.
Nitrogen – needed to make amino acids and protein for growth.
All these minerals must be replaced in the soil to maintain plant growth.
Natural and Artificial Fertilisers
Both natural fertilisers (farmyard manure and compost) and artificial fertilisers may be used to replace nitrates and other minerals in soil.
Comparing natural and artificial fertilisers
Eutrophication
The problem with using fertilisers is that not all the nutrients sprayed onto fields gets used by plants. Both sewage and fertiliser ‘run-off’ can cause eutrophication.
Key points:
Nitrates from sewage and fertiliser cause an increase in the growth of aquatic plants and algae;
The plants die due to shading (as they cannot photosynthesise) and both plants and algae die to due the eventual decrease in concentration of nitrates available (nitrate depletion);
The dead organisms are broken down by decomposers, which further depletes oxygen levels in the water;
Other aquatic vertebrates and invertebrates die due to oxygen depletion.
Acid Rain
Using the textbook p66 – 67, create an annotated diagram/poster about:
1. the causes and
2. effects of acid rain and
3. strategies to reduce acid rain.
Make sure you include detail.
Using the information in the previous slide, plus Figure 7.21, p66 in GCSE textbook,
design a summary poster
to explain how
eutrophication is a
consequence of water pollution.
Include in your poster the ways that this type of pollution can be reduced (read section on ‘Water pollution’ p66).
Summer extended writing task
Choose one of the following topics to research over the holiday, giving details/examples of how the localenvironment has been impacted.
1. Methods of monitoring change in the environment
2. The role of the Government in conserving the environment
3. Changes in agriculture (including EU Nitrates Directive)
4. International co-operation and legislation.