Humans have not affected the sand dune ecosystem on the North Norfolk Coast.
Contents
Introduction... Page 2
Chapter 1... Page 5
Chapter 2... Page 8
Chapter 3... Page 16
Chapter 4/ Conclusion... Page 21
Hypothesis: Humans have not affected the sand dune ecosystem on the North Norfolk Coast
Introduction
The purpose of my investigation is to discover if the humans have had an impact on the North Norfolk Dunes. I have chosen this site as it is a well established dune ecosystem. An estimated 9% of the English coastline has a dune ecosystem on it, as the UK population is around 58 million people they can be a lot of human impact inflicted upon them.
The North Norfolk sand dunes are within two hours of three major conurbations like London, Nottingham and Birmingham. It will be an estimated two hour bus journey from me. Whilst at North Norfolk I will be doing various studies for example:
* % Vegetation cover
* % Bare sand or soil
* No. of species
* Ph level
* Infiltration rate
* Soil colour
To measure vegetation cover and the percentage of bare sand or soil I will simply place the quaderat down and see what you can see within it. From this I will also be able to determine the number of species that exist there. To measure the Ph level I will take a probe and place it in the ground, from this I will get an accurate reading from the sand/soil.
To measure the infiltration rate I will take an infiltration cylinder and place it in the ground I will then pour approximately two inches of water in and time the rate of infiltration. Finally to determine the soil colour I will take a small sample from each site and place it in a clear, sealed bag. In addition I will use a colour coding kit to discover the actual colour.
To achieve this will be using a quadrat to determine what plant life exists (if any) on the dunes. I will also be doing an environmental impact matrix to see what damage I believe humans have done to the area. From this I hope to find if humans have had an effect on the Norfolk Dunes.
Food Chain:
On my visit, I will also be concentrating on the sand dune ecosystem as a habitat, as well as geographical survey. I have predicted what I expect to come across on my visit, and I have displayed this in a food web.
The above food web shows a predicted overview of what I will come across at North Norfolk. The arrows show the flow of energy. Here is one of the food chains explained:
A skylark eats flowers that are colonised on the dune. A hedgehog then eats the skylark, and a fox then eats the hedgehog
Here is a picture of the area I will be studying
Chapter One
During this investigation I will hopefully come across all different types of material along the beach and the dunes. Quite a lot of this damage is a result of erosion. Erosion is a result of waves hitting the cliff side or dunes and breaking of materials, as a result of this heavy damage could be caused. I predict that coastal erosion could be a factor in North Norfolk and affect the dunes and agricultural land.
A sand dune ecosystem is a result of a process known as succession. The wind blows sand to form dunes but the sand will blow away if there are no plant roots to stabilise the dunes. The first plants to colonise the area are called pioneer species. These are tough and are adapted to the harsh conditions. They can cope with dry conditions and being constantly covered in sand. As the dunes stabilise more plants can start to colonise. As the plants die they release nutrients which help to build up the organic content of the soil and will therefore allow a higher diversity of species to develop. The succession will continue until it reaches its climax community. This is where the habitat is stable. The coursework will determine if the climax community has been achieved naturally or has there been a significant human impact?
Above is a diagram showing the effects of Long shore drift. The arrow at the bottom corner shows the prevailing wind coming from the south westly direction. Number one then shows the Swash and number two shows the Backwash which is happening in a zigzag motion.
Another coastal process happening is transportation, waves rarely approach a beach at right angles, they usually approach at an angle that depends on the wind. The waves break and water rushes up the beach and the backwash brings material down due to gravity. Another wave hits the beach and the material ...
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Above is a diagram showing the effects of Long shore drift. The arrow at the bottom corner shows the prevailing wind coming from the south westly direction. Number one then shows the Swash and number two shows the Backwash which is happening in a zigzag motion.
Another coastal process happening is transportation, waves rarely approach a beach at right angles, they usually approach at an angle that depends on the wind. The waves break and water rushes up the beach and the backwash brings material down due to gravity. Another wave hits the beach and the material is carried in a zigzag motion, this is known as longshore drift. Longshore drift can seriously damage beaches. To help prevent this fences are built called groynes. These reduce the force of the waves and trap the sand in the process. It also prevents coastal erosion by protecting the dunes from the sea.
Another coastal process would be deposition. This occurs in sheltered areas where the sea can no longer erode or transport material. Most of the time this occurs when the waves are at there most gentle. The most common type of deposition feature is the beach, which is made up of either sand or shingle. The beach is not permanent feature, its size and shape changes every time the tide comes in and goes out.
If deposition is a problem I may find examples of a spit. A spit is sand and pebbles joined to the land at one end. These are features of coastal deposition and tend to be formed by longshore drift. Many of them extend out at a gentle angle towards the sea and have a curved or hooked end. I am predicting there may be evidence of a spit at Wells next the sea.
The picture above is an example of a well formed spit in New Zealand, I have used this to show how a spit looks.
To collect my data I will need to use systematic sampling, I will used a framed quaderat and sample along the transect every 10 metres. I will use the quaderat to measure 4 to 5% of the transect to identify the properties and features of the ground e.g. Soil, sand and plants etc. I am predicting there will be some kind of sea defence; this will probably include the use of gabion boxes. Gabions are rectangular steel wire mesh baskets to be filled with stones. Each gabion is usually divided into cells by wire mesh panels called diaphgram to stregthen them. They are usually used for sea and lake shore protection.
Chapter 2
The particular area I was studying was probably the best natural sand dune ecosystem in North Norfolk, which agrees with Sue Warn's statement "It was one of the best natural sand dune ecosystems in England" I agree with this because no human impact was apparent in the dune slacks and embryo dunes. The only minor impact was to the mature dunes, where people were walking dogs and people trekking on horses, however this was only permitted in the out of season. I discovered litter near the climax community and evidence of charred wood which was probably used for a barbeque.
The area we started at was the embryo dunes; this area was 80 to 100% bare sand. This was because there was no decaying matter and not enough soil present for Marram grass to grow.
Throughout the embryo dunes I noticed a pattern, the further up the beach I tested the more vegetation cover there was. This was because Marram grass was beginning to stabilise the dune so more and more could grow.
However after this stage I reached the dune slack, from here there was no vegetation cover and 100% bare sand, I also noticed there were no species of plant present. At high tide this area was covered and left saturated, this is probably the reason why nothing was growing. I also noticed the sand was rippled, this told me the direction of long shore drift, this had carried shingle and debris with it which is some areas of the slack was quite noticeable.
The Ph level in the dune slack was slightly acidic but I cannot determine why. One important thing I did notice was the rate of infiltration, in this area it was up to two times slower I believe this was due to the sand already containing a high volume of water. The only thing present in this area was silt, pebbles and shells which had been carried at high tide.
Here is an image of the dune slack
I then moved on to the mature dune area and noticed the dune had become very stable; it had also reached its climax community as Marram grass was visible along the dune.
However at the start of the dune there was still 60% bare sand. At this stage no soil was visible. The Ph level was still averaging at about six which is very slightly acidic. In this area the infiltration rate was a lot quicker, it was around 8 - 10 seconds and the sand was a golden brown colour.
The final sampling was actually in the climax community; this area was 120 metres away from the embryo dunes and was the final stage of my samplings. This area shown a huge difference, in here there was a 100% vegetation cover and several numbers of species including Scots pine, moss, plants, spiders and small birds. In addition I found the Ph level to be slightly higher, it was around 7.5 which shows it to be alkaline, because of all the plant life and moss the infiltration rate was very slow, it took around 41 seconds for the water to filter through the cylinder. All my results I have retrieved agree with Sue Warn's theory and therefore proves this area was a well established sand dune area.
Here are my bi-polar results for his area
Litter
2
3
4
5
No litter
Trampling
2
3
4
5
No trampling
Buildings
2
3
4
5
No buildings
Fences
2
3
4
5
No fences
Litter bins
2
3
4
5
No litter bins
Beach management
2
3
4
5
No beach management
Sea defences
2
3
4
5
No sea defences
A low score would represent a lot of human impact while a higher score means less human impact. In total, I gave this site 28/35. This basically means that there was very little human impact. There was very little litter and there were no buildings, fences, litter bins and sea defences. There was a lot of beach management with the pine trees being planted. There was also a lot of trampling which would be expected, as it is a public beach where a lot of people visit.
I have placed all the classes' results into this table to find out if the results are similar. The table is shown below.
2
3
4
5
Litter
2
0
4
3
0
No litter
Trampling
3
2
2
No trampling
Buildings
5
0
2
No buildings
Fences
0
0
0
0
9
No fences
Litter bins
0
0
0
0
9
No litter bins
Beach management
0
0
0
8
No beach management
Sea defences
0
0
0
0
9
No sea defences
At site 2, there was some evidence of a sand dune succession as there were some embryo dunes. The dune slack is covered at high tide but contains
I didn't take any measurements of pH level, infiltration rate and number of species present for site 2 because the information would have been very similar.
There was some evidence of human impact at site 2.
These included the building of:
* Steps
* Fences
* Beach huts
* Groynes
* Planting of pine trees
The steps were a main point of this site. They were built to help walkers reach higher parts of the beach without damaging vegetation and to make it easier to reach the beach. They also give a view of the whole beach as shown in the photograph below.
Another feature of this area was the fences built to protect plants and to allow visitors to see plant species without damaging them. These are built along the steps so tourists can see them as they walk down the steps to the beach.
Along the beach were the beach huts people either buy beach huts to have a small, safe place to stay in the rainy or cold weather but some people rent their beach huts to tourists. Beach huts are built on stilts to help them be protected from possible storms or high tides. The picture below shows the location of the beach huts in comparison to the sea. The beach huts are just behind the groynes. The paragraph below explains why this needs to happen.
Along the beach the groynes were constructed to trap sediment. This trapping of sediment is called longshore drift. Because there is no sediment, erosion is reduced which therefore protects the land behind. The diagram for beach huts above includes the location of groynes. The groynes are built here to protect the beach huts from storms and high tides. The groynes reduce the force of the waves.
Along the dune pine trees were planted to help protect the land behind them. This shows that the dune has reached its c limax community and is stable enough to allow the pine trees and plants to grow on them. As you can see in the picture below this sand dune has been stable for a long period of time has lots of species of plant and trees have grown on them.
For this area I made a bi-polar chart shown below:
Litter
2
3
4
5
No litter
Trampling
2
3
4
5
No trampling
Buildings
2
3
4
5
No buildings
Fences
2
3
4
5
No fences
Litter bins
2
3
4
5
No litter bins
Beach management
2
3
4
5
No beach management
Sea defences
2
3
4
5
No sea defences
I gave Site 2, a score of 23/35. Basically, this means there has been human impact but only small sections of the site were changed. There was lots of beach management.
These included:
* Fences around the blackberries
* Groynes to stop longshore drift and to trap sediment
* Steps to improve accessibility to the beach
* Pine trees to reduce the effects of erosion
* Beach huts being built along the sand to house tourists
There was quite a lot of trampling where lots of tourists had walked along the beach. There were some sea defences, a few buildings (beach huts). There were no litterbins as there were only traces of any litter. I will now compare this to our class results:
2
3
4
5
Litter
2
0
2
No litter
Trampling
8
2
5
0
No trampling
Buildings
7
2
2
3
No buildings
Fences
4
8
0
3
No fences
Litter bins
0
2
4
9
No litter bins
Beach management
3
0
2
0
No beach management
Sea defences
4
5
5
No sea defences
Chapter Three
This is site three and contains the most evidence of human impact with buildings and boardwalks. It is obvious that this is a main entrance for the tourists has they built access walks to get on to the beach. The estuary next to this area had been dredged and marked for yachts and boats to get through without grounding.
In the picture above the area of water we can see has been dredged in order for boats to gain access through safely. This is safely watched by a control station at the highest point of the beach. It case of any trouble they can contact the boats through radio transmission.
Below is a sketch of site 3 and I have pointed out the important features in this area. However some of the main features of this area are out of view. These are such things such as the lifeguard station, the control station and a concrete runoff for the boats to enter the water
There were lots of signs near site 3 informing tourists of beach management methods and safety signs. These included:
* "No dogs on beach" sign
* Information about possible flooding in the area of Wells-Next-The-Sea
I also have bi-polar results for this area and they are the following:
Litter
2
3
4
5
No Litter
Trampling
2
3
4
5
No Trampling
Buildings
2
3
4
5
No Buildings
Fences
2
3
4
5
No fences
Litter Bins
2
3
4
5
No Litter bins
Beach management
2
3
4
5
No beach management
Sea Defenses
2
3
4
5
No Sea defenses
Site 3 scored a total of 12/35 which shows that there is a lot of beach management and a high amount of impact to the area. I will now compare these to the rest of the class.
2
3
4
5
Litter
0
5
5
7
No Litter
Trampling
9
3
3
2
No Trampling
Buildings
1
2
3
No Buildings
Fences
8
6
0
3
No fences
Litter Bins
0
7
5
3
3
No Litter bins
Beach management
6
1
0
0
No beach management
Sea Defenses
6
2
0
0
0
No Sea defenses
To look how many people were visiting the North Norfolk dunes with their own transport, I counted the amount of cars and coaches at 2 different points in the day (12.15pm and 1.40pm) I then used these figures to produce a bar chart. This clearly shows that slightly more people visit the North Norfolk dunes later on during the day. To make these results more accurate and reliable, I could have counted the number of cars at a few more times in the day. I could have also spaced the times out a bit more. Below is a graph to show this.
Conclusion
When I visited Wells-Next-The-Sea in North Norfolk, my aim was to either prove or disprove the hypothesis of:
Humans have not affected the sand dune ecosystem on the North Norfolk Coast
After I looked at the evidence I collected, it was very clear that the hypothesis was wrong. There was a lot of human impact, which prevented the sand dunes from naturally completing its natural succession. This was apparent in all three sites however site 3 for example had been affected more compared to site 1 which was only slightly affected by humans.
From looking back on the bi-polar results from all 3 sites, I noticed that generally the scores were lower on site 3. Because a lower score means more human impact, this indicates that there was most human impact. A majority of site 1's scores were at the top end of the graph. Site 1 received high scores for no litter, no buildings, no sea defences, no fences and no litterbins. It received low scores for trampling and beach management. Likewise, site 2's scores were situated around the middle of the graph. It received a low score for no trampling and no beach management. It received a high score for no litterbins but received a mid-score of 3 for:
* Buildings
* Fences
* Sea defences
Site 3 received low scores for beach management, sea defences, fences and trampling. Site 3 received mid-scores for litter, buildings and litterbins.
The total scores for each site is shown below:
Site
Total score
27
2
21
3
5
Matthew Branston
