A study on the water quality of
Austwick beck
By Alec Christie
Aim
In the main investigation of this project, I hope to explore how the
water quality of Austwick beck in North Yorkshire varies along its
course at sites I have located to test the water, 1, 2, 3 and 4; I will be
also be looking into what (if any) effects the weather has on the results
of water quality of the beck, as a further investigation done only on
site 3.
There are four different factors that I will use to help determine the
quality of the water in Austwick beck, they include:
 The Turbidity
 The Temperature of the water
 The levels of dissolved oxygen
 And the pH of the water (the acidity or alkalinity)
I will now explain the meanings of these four variables and why they
are vital for supporting life, over the next few pages.
The Turbidity
The Turbidity is the how we measure the clarity of the
water, showing the amount of material, including dead
matter, waste, the load that the beck carries in suspension
and the amount of algae; all of which can have different
effects on the river’s precious ecosystem and other aspects
of the river that have connections and consequences with
and on the environment around it. For example, if the water
clarity is very poor there will be less sunlight able to
penetrate through to the oxygenating plants that need it to
fuel photosynthesis, which provides oxygen for organisms
that live in the water, which in turn feed or are needed by
organisms higher up the food chain and in and out of the
water. As you can see the Turbidity of the water is
imperative for ecosystems to function properly and for food
chains to remain intact.
The Temperature
Many aquatic animals are extremely sensitive to changes in
temperature. They are used to natural changes in the temperature, for
instance, when the sun is at its highest in the day, organisms are able
to cope with the extra heat and also when it is night, they can survive
the colder conditions. It is changes in the range of temperatures that
can be catastrophic for life in the river; if the temperature is over or
under the specific levels for sustaining life for a long period of time,
then many animals like fish become stressed and die, many will leave
and plants will stop producing oxygen, killing the few remaining
creatures that are left. Of course the temperature range of river’s vary
from place to place and in different seasons, for which most the
animals that live in them are adapted to. However, with urbanisation
increasing, more and more factories, houses and other buildings that
release warm water, toxic waste and dirty water are contributing to
unnatural temperature fluctuations, endangering the ecosystem and
animals that live within it.
The Saturation of Dissolved oxygen
The amounts of dissolved oxygen in rivers is extremely important to keeping the
ecosystems within them healthy. Of course, all aquatic animals need oxygen to live
and so without enough dissolved oxygen in the water, most of life would inevitably
die. Many natural and human implications can cause the availability of dissolved
oxygen to change, endangering the ecosystems that rely on it. When measuring
dissolved oxygen, the main readings are ppm, parts per million or ppt, parts per
thousand but it can sometimes shown as a percentage of saturation and this changes
with the temperature of the water. For example, if the water is cold at 8 degrees
Celsius, then the river may be able to hold up to 12 ppm (parts per million) of
oxygen before it is saturated at 100%; but if the water is at 28 C, the water will
become 100% saturated at 8 ppm – a smaller amount of oxygen. So, as you can see,
cold water can hold more oxygen that warm water. Fluctuations in the amount of
dissolved oxygen can endanger plants and animals abilities to thrive in rivers, which
could have repercussions back along the food chain and ecosystem. High levels of
bacteria and large amounts of rotting material can cause these adverse affects and of
course when the temperature fluctuates due to natural or unnatural causes, as was
explained on the last page, the dissolved oxygen will too because not only does this
reduce the amount of oxygen that can be stored by the water before it is fully
saturated but also impacts on the producers of oxygen, the plants, and if they start
dying and do not produce enough oxygen to keep other organisms alive, then the
whole ecosystem breaks down and dies too.
The pH
(the acidic or basic quality of the water)
Short for the potential of Hydrogen, the measurement of the pH of the
water is based on a scale from 0 to 14. Any reading below 7 is acidic
(0 being extremely acidic) and anything above 7 is alkaline (being
extremely basic), with 7 being neutral. Animals living in river’s are
adapted to the pH of the river, and changes in this can be extremely
detrimental to all life in the river. First of all, the average healthy pH
range for aquatic animals to survive in is from 6.5 (being slightly
acidic) to 8.0 (being slightly alkaline – or basic). If the pH changes,
animals can stop reproducing, move away from the area and of course,
die. Changes in this can be brought about by many things, such as:
acid rain (atmospheric deposition), wastewater discharges and
drainage from mines.
Introduction
to Austwick
beck
Austwick beck is situated in the
Yorkshire dales, in north-west
England and runs through to the
river Wenning which in turn
flows into the river Lune.
This is a map of the
course of Austwick beck.
It travels from the high
ground at the first test
site, down through
farmland and a few rapids
to the village of Austwick,
where I live.
The beck starts off out of a cave at the head of the beck, just before the
first test site. Here it travels relatively smoothly through marshy/bog-like
farmland (with livestock and no tree cover), to the second test site.
Austwick beck head
When the second test site is reached, the
gradient increases slightly and there is a
miniature waterfall with rapids where it
descends a little faster. Here there is access for
animals and people and no tree cover.
There is a large gap between the 2nd and 3rd test site where the
river isn’t accessible. And midway between the two sites the beck
levels out and starts to meander after the 3rd test site through
where there are some small rapids too. Most of the way along from
where the beck planes out, there are a lot of opportunities for
livestock to access the stream – something that will be of
importance later on. The 3rd test site has a lot of tree cover and
there is access for people and animals too.
At the 4th and last test site, the
stream runs under a bridge
after passing through some tree
cover and land with livestock
in. The actual test site has a
little tree cover and is also
accessible to people and
animals. This is where I decided
to stop following the course of
the river, from here the beck
runs into the river Wenning,
joining at a confluence with two
other becks’, Fen beck and
Clapham beck. The river
Wenning eventually goes onto
flow into the river Lune, which
makes Austwick beck a
tributary of a tributary of the
river Lune.
Theories:
The Turbidity
Turbidity varies from place to place in rivers and can be caused by many different
factors. For example: areas that have higher amounts of livestock, people and other
animals that are able to access the river, should have lower levels of clarity as the
intrusion of animals and people will: stir up the bed load of the river, leave faeces
behind and drop material from elsewhere into the river. All this can cause the levels
of turbidity to rise and of course, the type of weather present will also have an
effect; most likely to be that if there is rain and wind there will be more material
stirred up by higher flows of water and more material deposited in the water by the
wind (leaves, branches, etc.) and in sunny, calm conditions there will be a high
clarity of water as there will be little to disturb the bed load or cloud the water with
other materials. Low levels of turbidity are needed to support life; too much and
plants stop producing oxygen by way of photosynthesis as the area that sunlight can
penetrate is reduced suffocating animals. In many cases rotting plants that cause
some of the turbidity also increases the temperature of the water, which again has an
impact on the amount of oxygen available and drives away aquatic animals which
cannot adapt to the changes in the temperature.
Temperature
The temperature of the water will of course will vary in different weather conditions
and according to the time of day. The water will normally be naturally cooler in the
morning and at night than at midday and in the afternoon; it will also be naturally
cooler in the rain and wind than in the sun because the air temperature will become
cooler in wet and cold weather and warmer in dry, sunny conditions. The humidity
of the day will also change the temperature of the air and in turn that of the water, so
the amount of cloud cover will also affect the temperature too. The amount of tree
cover providing shade will also have an effect on the temperature of the water
because the more shade and tree cover there is, the less heat there will be to warm
the water and the lower the temperature of the water will be. Another factor is the
amount of livestock nearby that have access to the water. More faeces will be
produced and left to decay in the river as well as other decaying material such as
plants and dead bodies of animals which may warm up the water. Factories and
towns nearby may also have effects as drains, warm water discharges and other
flows of water into rivers may lower or increase the temperature. Organisms rely on
stability of natural temperature ranges that they have adapted to, to survive. If
temperatures fluctuate too much, the amount of dissolved oxygen will decrease and
will kill animals.
Dissolved oxygen
Higher levels of dissolved oxygen will normally be found by rapids or waterfalls
where there are larger amounts of ‘white water’ where air bubbles enter the water’s
surface and therefore increase the levels of oxygen present. However, areas of marsh
and bog-land, the amount of dissolved oxygen found in the water there is naturally
lower because there is naturally more decaying material (which is really microorganisms feeding on dead material and because there is more dead material to be
eaten and cleared away by them, they need more oxygen to do this, using up more
oxygen and lowering the levels of it in the water in the process).
Plants are the main sources of dissolved oxygen and when they photosynthesis,
more oxygen is produced. However the amount of plants that can photosynthesis
changes due to other factors including: the turbidity (the clearer, the more light for
plants to produce oxygen), the temperature (higher temperature, normally more
sunlight, more photosynthesis) and also the amount of toxic chemicals in the water
(more waste, kills more plants, less oxygen from less plants). But of course
dissolved oxygen can vary because it has a direct link with the temperature of the
water so it will rise and fall in accordance. If the temperature is low then the amount
of dissolved oxygen that can be dissolved below the saturation level will increase
but when it warms up, the saturation level will be lowered and thus less oxygen will
be dissolved, no matter if more plants are photosynthesising. Higher levels of
dissolved oxygen mean more oxygen for organisms to survive on.
pH
The natural pH of a
river is normally
between 6.5 – 8.0 on the
scale of 0-14. This is the
range that fish and other
aquatic organisms prefer
to live in. Any higher
(more alkaline) or lower
(more acidic) and the
ecosystem will break
down.
This has been seen in many areas of Scandinavia where acid rain (atmospheric deposition
coming over from the U.K and other countries) is decreasing the pH of the water in lakes,
making it more acidic and this is killing thousands of fish. Towns and villages can also be
affect the pH of river by releasing wastewater from factories and drains in mines. So a
balanced pH between 6.5 and 8.0 is essential for supporting life in rivers.
Hypotheses for water quality on
test sites 1, 2, 3 and 4
The Turbidity:
I would expect to find higher levels of turbidity from samples in test sites 1
and 4 whereas I would expect that test sites 2 and 3 would have slightly
lower levels (higher clarity). This is because sites 1 and 4 are nearest to
places where animals are likely to enter the water and excrete waste, stir up
some of the bed load, maybe trample in some material from the banks of
the river and also deposit materials they have picked up on their body from
elsewhere, thus reducing the clarity of the water. However in site 3 there is
no area for livestock to enter the water – there is access for people and
other animals such as dogs and horses to enter, but they can only enter at
least five or six metres down stream from the actual testing area so the next
site downstream (site 4) is likely to pick up the material instead.
The same goes for site 2 where livestock cannot enter, here however people and other
animals can enter the water upstream from the test area, although I doubt that this will
have much of an effect on the overall turbidity as most of the material that is deposited in
the process will probably be left on the rocks forming the miniature waterfall/rapids.
Therefore I predict that the turbidity will be higher in places where livestock have the most
access to the specific site; livestock has the most access to the stream at the start and finish
of the stream section that I am testing, so sites 1 and 4 (nearest in terms of being
downstream to livestock ‘hotspots’) should have higher turbidity.
Site 4
Site 4 has
livestock
grazing up
stream so it will
therefore have a
higher turbidity
than site 3
which is
relatively free
of livestock
and other
animals
Site 3
The Temperature
The temperature of the water will vary but will probably be generally low as the climate at this
time of year for northern England is quite cold. Like I stated in the last paragraph, the amount
of waste excreted by livestock on farmland may have an effect on some of the tests, in this case I
would expect it to increase the temperature of samples from sites 1 and 4 slightly because they
are the sites nearest (downstream) to where animals are likely to excrete waste – which is going
to increase the water because it has a higher temperature than the water itself. There have been
quite a few sightings of fish and other cold-blooded animals in the river which indicates that the
water is cold enough for them to live in. There have also been sighting of birds such as
kingfishers, herons and dippers which feed on organisms in rivers. This indicates that the
temperature of the water is the cold enough (but not too cold) to be able to support cold-blooded
life and also plant life too as each part of the food chain must be functioning properly if all the
organisms within it are healthy. The area around sites 3 and 4 (refer back to the maps in the
introduction), are quite overgrown and shrouded by trees and plants; this will cut off sunlight
from heating the river but may also cause a higher humidity if it is already cloudy but mild – so
the effects that this may have on the temperature of the water are debatable as it all depends on
the type of weather present. However on sites 1 and 2 it is quite easy to predict whether the
temperature will be higher or lower in hot or cold weather because they are open and un-shaded;
this means that if the weather is warm and sunny, the water may be warmer, if it is cold and
cloudy, then the water may be cooler.
Therefore, taking everything into account, I predict that the temperature of the water from sites
1 and 2 will be warmer than water from sites 3 and 4, that is, in warm weather. However, in
cooler weather, I would not expect there to be a large difference in temperatures because the
waste excreted by animals may level out the range of temperatures increasing site 1 and 4’s
temperatures but leaving site 2 and 3’s around the same. The weather on the day of the tests will
ultimately decide whether the temperature will be higher or lower but generally as I said, I
would expect the weather to be cool as the climate is generally at this time of the year, so I would
expect little, if any, difference in the temperatures of the water samples from different sites.
Dissolved oxygen
The amount of dissolved oxygen will probably be reasonably high for all sites because it’s
getting quite cold up hills of the dales now it’s getting into autumn because cooler water
holds more oxygen than warm water does. On the other hand, the days are getting shorter
with less sunlight so there is less time for plants to photosynthesis, which also means that
there is also less time for oxygen to be produced by the oxygenating plants in the beck
which will the lower the amount of dissolved oxygen in the water even though the capacity
that cold water can hold is high. However I suppose because the high ground nearer the
head of the beck is more bog-like that it will have naturally low levels of dissolved oxygen
than the ground lower down in the valley because of the naturally higher amounts of
decaying matter including faeces from the livestock. However, there is quite a lot of
livestock on the lower levels too, which
Site 4
may also lower the amount of
dissolved oxygen in those places, not
only by introducing more decaying
Livestock producing
matter but also by heating up the river
slightly by excreting waste which is
faeces, contributing to
warmer than the water’s temperature.
higher turbidity and
The waste from livestock may also
decreasing the amount of
encourage algae to bloom, which may
dissolved oxygen
absorb most of the oxygen and cut off
light for plants – slowing down the
Algae encouraged to
process of photosynthesis or stopping
bloom by waste from
it in some places – which will lower
Livestock, which then uses
amount of dissolved oxygen being
produced and kept in the water.
up oxygen
Dissolved oxygen continued:
I would expect to find higher levels of dissolved oxygen in the parts of the river where there
are waterfalls or rapids as the water there will be travelling faster than in the other places
in the river. This will mean the air particles hitting the water will be hitting it with much
more force than normal (producing the noticeable ‘white water’ where the air bubbles are
travelling into the water because the water particles are hitting the air with more velocity)
allowing more oxygen into the river than anywhere else, resulting in higher dissolved
oxygen levels. Another factor in how the dissolved oxygen may vary in different parts of the
river is the amount of tree or plant cover. The lower levels the 3rd and 4th test sites, (refer to
maps) of the river become more overgrown and shrouded by trees, this will result in less
sunlight getting through to the plants in the river, which in turn will mean that less oxygen
is produced in photosynthesis by the plants as sunlight plays a key part in the process, so if
you reduce sunlight you reduce photosynthesis and you reduce the amount of dissolved
oxygen. So even though the water temperature may be lower because of the lack of heat
from sunlight, and will therefore increase the amount of oxygen that it will be able carry
before the saturation level is met, if the sunlight is not allowing plants to photosynthesis to
produce oxygen then the levels of oxygen will remain low.
So overall taking into account of the temperature, the river’s features (small
rapids/waterfalls/tree cover etc.) and the amount of time plants have for photosynthesising
in the day, I would say that the stream will have a moderate-high amount of dissolved
oxygen in the water but not in all places; there should be higher concentrations near the
rapids (site 2) and lower concentrations near where livestock are grazing by sites 1 and 4.
So, the nearer to livestock and natural sources of decaying material the water is, the less
oxygen there will be and the nearer (downstream) to rapids and waterfalls the water is the
more oxygen there will be.
pH
Bog land
Naturally acidic
Site 1
Water will
therefore be acidic
On the higher levels of
the river near the head of
the beck, the land
becomes a bog which
means the water there
should be naturally more
acidic because bogs are
naturally acidic. The
water in the lower levels
of the valley where the
ground is just normal
farmland should have a
more neutral pH as there
are no natural factors
that will change the
acidity significantly.
There is no noticeable acid rain to cause the pH of the water to decrease (in fact there is a
strong population of lichen in the area which indicates that acid rain does not fall around
here, otherwise there would be no lichen as acid rain is lethal to mosses such as lichen).
Therefore, I would expect the pH of the water in sites 1 and 2 may be lower (more acidic)
than in sites 3 and 4 where the water should be more neutral – the nearer the naturally
acidic bog the site is, the more acidic the water will be.
Weather conditions
Turbidity:
I would expect the turbidity of the water to increase in wet, windy weather because
there would be more water flowing through the test area to stir up material from the
banks, such as mud and soil, and also the bed load that the river is carrying. The
wind would also blow in materials such as leaves and branches which would add to
the high levels of turbidity. However in dry, sunny conditions or when it is cloudy
and dry, there will be little to disturb the bed load or brush in material from the
banks, resulting in lower levels of turbidity and higher levels of clarity. Therefore, I
expect that the turbidity will be high in wet and windy weather whereas when it is
dry, sunny or cloudy, the turbidity will be lower.
Temperature:
The Temperature of the water will of course – as I said in the last set of hypotheses –
vary depending on the weather. I would expect the temperature of the water to rise
in warm weather, but fall in cooler weather when it rains or when there is a lot of
cloud cover because the lower air temperature will force the water temperature
down.
Dissolved oxygen:
I would expect dissolved levels to increase when there is rain because as the rain
drops into the water, it carries with it oxygen which adds to the amount already in
the water. However in warm weather, more water is likely to evaporate and take
away dissolved oxygen within the water vapour. With cloudy weather, I doubt the
levels will change much and will probably stay at a moderate level. Therefore, the
higher the temperature, the less oxygen there will be because some of the oxygen
will be carried away with the evaporated water, however, the wetter and cooler the
weather the more oxygen there will be as less of it will evaporate in water vapour
and more will inputted into the stream through precipitation.
pH:
I would expect little change in the pH during different types of weather conditions as
the weather has little to do with the acidity of the water, apart from rain. It would
however have more of an effect if acid rain was common but as there is little, if any,
acid rain in the Yorkshire dales (proven by the large amount of lichen here) I do not
see how the weather conditions will have any affect on the water’s pH. Therefore, I
do not predict any change in the pH in different weather conditions.
Methods for tests:
For the weather condition tests, I used site 3 only as this was the site closest and most
conveniently positioned from where I could easily see what the weather was going to be like;
I went out and collected the data on different days when the weather conditions varied the
most. The water quality tests for the whole river were all performed on the same day so that
varying weather conditions that may affect the results (something which I wanted to
investigate in the other tests on site 3), would not be present to interfere with the accuracy
of the results.
Overall equipment needed:
•
•
•
•
A ruler,
Rubber gloves,
A watch or timer,
A world water monitoring
day kit, (which includes:
container for collecting
samples, adhesive Secchi disk,
turbidity/pH/oxygen ppm
chart, two adhesive
thermometers (high and low
temperatures), test sample
vial, test tube, TesTabs®
tablets for dissolved oxygen
and pH tests, booklet for
information and recording
data).
Collection procedure:
1.
Remove the cap of sampling jar.
2.
Wear protective gloves. Rinse the jar 2-3 times with the stream water.
3.
Hold the jar near the bottom and plunge it below the water surface.
4.
Turn the submerged jar into the current and away from you.
5.
Allow the water to flow into the jar for 30 seconds.
6.
Cap the full jar while it is still submerged. Remove it from the river immediately.
Turbidity test
Method:
Equipment:
Adhesive Secchi disk, turbidity chart
and kit sampling jar.
1.
Remove the backing from the Secchi disk icon sticker.
2.
Adhere on the bottom of the kit container. Position the sticker slightly
off centre. If possible adhere to the jar 8-24 hours before use to allow
the adhesive to cure.
3.
Fill the jar to the turbidity line located on the label as in the collection
procedure (see last page).
4.
Hold the turbidity chart on the top edge of the jar looking down into
the jar, compare the appearance of the Secchi disk icon in the jar to
the chart. Record the result as turbidity in JTU.
Temperature test
Equipment:
Sampling jar with thermometers adhered onto it,
ruler and timer.
Method:
1. Wear protective gloves
2. Place thermometer four inches below the water
surface for one minute.
3. Remove the thermometer from the water, read
the temperature and record the temperature as
degrees Celsius.
Dissolved oxygen test
Equipment:
Sampling jar with thermometers, small vial, timer, two
Dissolved Oxygen TesTabs®, dissolved oxygen chart and
booklet table to determine saturation level.
Method:
1.
2.
3.
4.
Record the temperature of the water sample
Submerge the small vial (0125) into the water sample.
Carefully remove the vial from the water sample, keeping it
full to the top.
Drop two Dissolved Oxygen TesTabs® (3976A) into the vial.
Water will overflow when the tablets are added.
Screw the cap on the vial. more water will overflow as the cap is tightened. Make
sure no bubbles are present in the sample.
5.
Mix by inverting the vial over and over until the tablets have disintegrated. This
will take about 4 minutes.
6.
Wait 5 more minutes for the colour to develop.
7.
Compare the colour of the sample to the dissolved oxygen colour chart. Record the
result as ppm dissolved oxygen.
pH test
Equipment:
Test tube, one pH wide range TesTab
and pH chart.
Method:
1.
Fill the test tube(0106 to the 10ml line
with the water sample.
2.
Add one pH wide range TesTab
3.
4.
(6459A).
Cap and mix by inverting until the
tablet has disintegrated. Bits of the
material may remain in the sample.
Compare the colour of the sample
with the pH colour chart. Record
result as pH.
Results of tests in different weather
conditions:
Weather
Conditions
Turbidity
Cloudy, not much
sunlight, fair
temperature.
0 JTU.
Partially cloudy,
warm, sunny.
Cloudy, windy with
heavy rain.
0 JTU
40 JTU
Turbidity
100
JTU
80
60
40
20
0
Cloudy, cold, dry
Warm, sunny
Cloudy, windy, rain
Weather conditions
Weather
Conditions
Cloudy, not much
sunlight, fair
temperature.
Partially cloudy,
warm, sunny.
Cloudy, windy with
heavy rain.
Water temp
10 Celsius.
12 Celsius
8 Celcius
Water temperature
°C
12
10
8
6
4
2
0
Cloudy, cold, dry
Warm, sunny
Weather conditions
Cloudy, windy, rain
Weather
Conditions
Cloudy, not much
sunlight, fair
temperature.
Partially cloudy,
warm, sunny.
Cloudy, windy with
heavy rain.
Dissolved oxygen
8 ppm, water
temperature 10
Celsius, 71 %
saturation
8 ppm, water
8 ppm, water
temperature 12
temperature 8
Celsius, 74%
Celsius, 68%
saturation
saturation
Dissolved oxygen
8
7
Dissolved oxygen in
6
Saturationin%
DissolvedOxygensaturation
100
96
92
88
84
80
76
72
68
64
5
4
3
2
1
0
Cloudy, cold, dry
Warm, sunny
Cloudy, windy, rain
Weather conditions
Cloudy, cold, dry
Warm, sunny
Cloudy, windy, rain
Weather conditions
Weather
Conditions
pH
Cloudy, not much
sunlight, fair
temperature.
8 pH.
Partially cloudy,
warm, sunny.
Cloudy, windy with
heavy rain.
8 pH.
8pH.
pH
Weather conditions:
Cloudy, cold, dry
14
12
10
8
6
4
2
0
Cloudy, windy, rain
Warm, sunny
The results of water quality on sites 1, 2, 3 and 4.
The Turbidity:
Test sites:
1
2
3
4
Turbidity
40 JTU
0 JTU
0 JTU
40 JTU
Turbidity
100
JTUof water
80
60
40
20
0
1
2
Test Sites
3
4
Test sites:
1
2
3
4
Water
temperature
11 °C
10 °C
10 °C
12 °C
Water Temperature
12
Temperature in °C
10
8
6
4
2
0
1
2
Test Sites
3
4
Test sites:
1
2
3
4
Dissolved
Oxygen
8 ppm, water
temperature 11
°C, 72.5 %
saturation.
8 ppm, water
temperature
10 °C, 71 %
saturation.
8 ppm, water
temperature
10 °C, 71 %
saturation
8 ppm, water
temperature
12 °C, 74 %
saturation
Dissolved oxygen
8
Dissolvedoxygen(ppm
7
6
5
4
3
2
1
0
1
2
3
Test sites
4
Test
sites:
1
2
3
4
pH of the
water
7.5 pH
8 pH
8 pH
8 pH
pHof the Water
14
12
pH
10
8
6
4
2
0
1
2
3
Test sites
4
Conclusions for weather
conditions
Turbidity Hypothesis:
I expect that the turbidity will be high in wet and windy weather
whereas when it is dry, sunny or cloudy, the turbidity will be
lower.
Conclusion:
The hypothesis was shown to be true as the results show no
turbidity at all in dry, cloudy and sunny condition but moderate
levels in wet and windy weather. So therefore it is true to say
that wet weather will affect the turbidity of the water by
increasing the turbidity by increasing the amount of material in
suspension and also material in the bed load. Dry or sunny
weather without rain will have no affect on the tests.
Graph on p29
Temperature hypothesis:
I would expect the temperature of the water to rise in warm weather,
but fall in cooler weather when it rains or when there is a lot of cloud
cover because the lower air temperature will force the water
temperature down.
Conclusion:
The graph shows that this is true, the temperature rose to 12 degrees
Celsius in warm sunny weather when the temperature was higher than
in cold, cloudy weather with precipitation when the air temperature
was lower at 10 and 8 degrees Celsius. It also shows that the direct link
between the temperature of the air with the temperature of the water is
true, and that when the air temperature rises the water’s temperature
will too and vice versa. So if there was rain on the day of the
experiment, you should expect to find lower temperatures and vice
versa in dry and sunny conditions depending on the air temperature.
Graph on p30
Dissolved oxygen hypothesis:
The higher the temperature, the less oxygen there will be because some of the
oxygen will be carried away with water vapour that the heat in warm weather
evaporates; however, the wetter and cooler the weather the more oxygen there will
be because less will evaporate in water vapour as there is less heat for evaporation to
take place and more will be inputted into the stream through precipitation.
Conclusion:
The hypothesis was proved to be incorrect because the ppm levels of each sample in
different weathers were found to be equal, all reading at 8 ppm. Moreover, the
dissolved oxygen saturation levels on the graph actually rose in warmer weather
rather cooler, however, this doesn’t really show that the hypothesis was wrong
because the ppm levels were all the same which means that the only reason why the
saturation levels differed was because of the temperature not the actual amount of
oxygen in the water. The kit I used only gave 3 readings of ppm for dissolved
oxygen: 0 ppm, 4 ppm and 8 ppm which only shows whether the water contained
poor, fair or good amounts of oxygen. Therefore, the kit isn’t very accurate for
measuring higher levels of dissolved oxygen from the water and if a more
sophisticated means of measuring the dissolved oxygen was used then differences
may have been seen that might have supported or disagreed with the hypothesis – so
the overall results should be seen as inconclusive.
Graph on p31
pH hypothesis:
I do not see how the weather conditions will have any affect on the
water’s pH; therefore, I do not predict any change in the pH in
different weather conditions.
Conclusion:
The results show that the hypothesis was correct, all samples in
different weather conditions had a pH of 8. This shows the weather
does not have any affect on the weather in this area but I should note
that in areas with regular amounts of acid rain, the result would
probably change and cause the water to become more acidic in wet
conditions when precipitation would bring in acidic substances
produced by air pollution from factories.
Graph on p32
Conclusions for tests on
sites 1, 2, 3 and 4
Turbidity hypothesis:
I predict that the turbidity will be higher in places where livestock have
the most access to the specific site; livestock has the most access to the
stream at the start and finish of the stream section that I am testing, so
sites 1 and 4 (nearest in terms of being downstream to livestock ‘hotspots’)
should have higher turbidity.
Conclusion:
The results show that the hypothesis was very accurate, sites 1 and 4 had
equal amounts of turbidity and were at higher levels than sites 2 and 3
which had no measurable turbidity. This shows that it is true to say that
livestock does have an impact on the turbidity of water and the closer a
test site is (downstream) to an area which has a large amount of livestock
that can access the river, the higher the turbidity will be and vice versa.
Graph on p33
Temperature hypothesis:
I predict that the temperature of the water from sites 1 and 2 will be warmer than water from
sites 3 and 4, that is, in warm weather. However, in cooler weather, I would not expect there to
be a difference in temperatures because the waste excreted by animals may level out the
range of temperatures increasing sites 1 and 4’s temperatures but leaving sites 2 and 3’s
around the same. The weather on the day of the tests will ultimately decide whether the
temperature will be higher or lower but generally as I said, I would expect the weather to be
cool as the climate is generally at this time of the year, so I would expect little, if any,
difference in the temperatures of the water samples from different sites.
Conclusion:
The day of the experiment was a cool, dry and cloudy day which meant if the hypothesis was
true, then the water samples from each site would not differ by much at all. Looking at the
results, the range (from the lowest to the highest) of temperatures was no more than 2 degrees
Celsius and showed there was little difference in the temperatures, proving the hypothesis
true in this aspect. The hypothesis was also shown to be accurate by predicting correctly that
sites 1 and 4 would have warmer levels than sites 2 and 3 because of livestock activity
upstream; the weather was cool so there was little heat to make a difference between the
temperatures of the shaded and un-shaded areas and this allowed the theory of how livestock
could increase the temperature in different ways to raise the temperatures of sites 1 and 4
above those of 2 and 3, regardless of whether they were shaded or not. So overall, the
hypothesis was shown to be true in cool weather.
Graph on p34
Dissolved oxygen hypothesis:
There should be higher concentrations near the rapids (at site 2) and lower
concentrations near where livestock are grazing (by sites 1 and 4). So, the
nearer to livestock and natural sources of decaying material the water is, the
less oxygen there will be and the nearer (downstream) to rapids and waterfalls
the water is the more oxygen there will be.
Conclusion:
Interestingly, the results showed that there was no difference in the results for
ppm, they were all at maximum ppm level for the test, but the saturation levels
differed slightly but because all the sites had the same amounts of oxygen, this
has little meaning in order to say whether one site is healthier than another.
Conclusion continued…
•
The fact that the kit that was used only measured up to 8 ppm in testing meant that the
results could only determine whether a site had a good, fair or poor amount of dissolved
oxygen and if a more broad test was used then the results may have differed and helped
to shed some light on whether the hypothesis was accurate or not. However, if the same
results were obtained with improved testing, then there are some explanations listed
below to show reasons why the levels of oxygen were equal:
There may have been an error in the testing process,
• There were noticeable amounts of decaying matter on
the river bed when I started to test the 2nd site (which I
had not expected to find until I got there) and this may
have neutralised the amount of oxygen that was added
to the water through ‘white water’ from the
waterfall/rapids upstream and caused the amounts of
oxygen to decrease to the levels of the other sites that
didn’t have ‘white water’,
• The river had enough places where ‘white water’
may have occurred that were inaccessible and out-ofview which may have made other test sites levels of
dissolved oxygen equal to those of site 2 because they
had in fact, equal amounts of ‘white water’.
Graph on p35
Moss is present on the rocks
which will fall into the river and
decay like other materials from
the banks of the river lowering
the amount of dissolved oxygen
pH hypothesis:
I would expect the pH of the water in sites 1 and 2 to be lower (more acidic) than that of
sites 3 and 4 where the water should be more neutral – the nearer the water is to a naturally
acidic area, the more acidic it will be.
Conclusion:
The results did not really agree with the hypothesis in this case, as the sites nearly had all
the same results of 8 pH with only site 1 having a result of 7.5 pH, only slightly different.
The results did show that site one, in the bog where the ground is naturally acidic, was more
acidic than the other sites but only by a small margin and even then it wasn’t even acidic, it
was between neutral and slightly basic on the pH scale. One reason for this that was not
acknowledged in the hypothesis is that the area around the test site is made up of limestone
pavements and rocks such as sandstone which all share one characteristic, they can change
the pH of water to a more alkaline one.
Limestone escarpment,
rain percolates
through and becomes
alkaline, groundwater or
subsurface flow then
runs into river
With precipitation percolating into these rocks (limestone pavements are
on the surface so percolation is sometimes experienced before infiltration)
and also runoff flowing into the river over these rocks, the water’s pH
would have been changed by their alkaline properties to become more
basic than preciously thought. However, the naturally acidic bog and soil
around the area would have then lowered the pH from a higher basic level
to only a slightly basic one. The lower areas may have also had their pH
reduced to only a slightly alkaline level by acidic substances, like
pesticides and fertilisers, introduced by livestock and biological factors.
So, all in all, the hypothesis seems to have overlooked some factors such as
the pH properties of local rocks which water would have had to pass
through to get to the river, and has therefore been shown to be inaccurate
in some ways.
Graph on p36
Limestone and other
alkaline rocks increase pH
then acidic soil from the bog reduces pH to
create slightly
alkaline water
Overall conclusion for Austwick beck
The tests showed that in all parameters, the water in Austwick beck is of a sufficient quality
to sustain a healthy amount of biodiversity to keep the ecosystems functioning at healthy
levels – the dissolved oxygen was at maximum levels on the testing scale, the pH was in the
boundaries of the range that aquatic animals prefer to live in, the turbidity was low and in
some places non-existent which is good for plants and animals and the temperature was at
a stable level to support the ecosystem around it and can relied upon to remain that way
seeing as the area it is situated in is quite rural and unlikely to see much more urbanisation
or increased amounts of pollution.
The beck was also shown to be
fortunate enough to remain
relatively unscathed by
pollution and other adverse
factors that are brought on
and created by man, as it
tumbles through beautiful and
rich countryside in the safety
of the Yorkshire dales national
park where the authorities
and environment agencies are
very protective of everything
within it, including Austwick
beck.
Overall conclusion for the effect the weather
has on the water quality
Overall, the weather was shown to have some effects on the results of water quality but
not in all parameters. The pH and dissolved oxygen content (the dissolved oxygen
content was debatable as stated previously, the test was not very specific or exact in its
measurements for oxygen) of the water did not change because of the weather but in the
temperature and turbidity tests, as expected, the results were varied. It is safe to
conclude then, that for turbidity and temperature tests, that the weather condition that
has the most bearing on the results collected is rain and wind with extensive cloud cover.
Evaluation
•
•
Overall I feel the data collection in the field and when writing up the results went very
well: most of the results agreed with their hypothesise, the kit proved simple, easy and
effective to use and the whole experiment was very enjoyable and still feels like a great
success.
However, I do think that there were a few areas that could have been improved, that is,
if more time or resources were at hand, these include:
The kit was simple to use and effective in most ways, however, I feel that the kit in some
ways, gave vague results, such as with the dissolved oxygen test, which produced the
same results of 8 ppm when in fact the ppm scale can go up as high as 16. If some more
advanced testing apparatus was used to do this test again then I expect the results would
have been more accurate and would have helped to conclude how dissolved oxygen
changes in places along the beck.
Also when the testing was actually performed, only one test per variable per test site was
achieved because of lack of time to walk to each site (there was also a delay on the day of
the tests when 2 of the original 6 sites where found to be privately owned and this
therefore used up a lot of valuable time spent walking to these sites), the overall walking
distance was around 5 miles (including the detour when 2 of the 6 sites were found to be
private) which had to be covered on foot while at each site testing for each parameter. If
there were more people to help me, apart from my poor brother who was dragged out(!),
then more sites could have been tested more than once because we could have
concentrated our efforts on one or two specific sites per person. If tests were done more
than once – three times would have been the most efficient – and the results totalled and
divided by however many tests (e.g. pH 8 + 6 + 7 = 21/3 = 7 average pH for site) to find
the average which then would have given a more accurate and reliable spread of results.
Evaluation continued…
So overall the two investigations proved very successful although as with any
experiments and projects, some adjustments and improvements could have
been made to ensure even more accurate and reliable results but I am pleased
with these results considering the amount of time and resources I had.
Thanks for reading!
Special thanks: I would like to say thank you to my younger
brother Scott in helping me collect the results, my whole
family in helping me in many areas of this exercise and to
Sword Scientific ltd who supplied the equipment.