The results I have collected will allow me to either prove

or disprove my 4 hypotheses. These are;

·

Soil moisture increases progressively away from

the sea

·

pH of the soil decreases progressively away from

the sea

·

Percentage of vegetation cover increases progressively

away from the sea

·

Dune height increases progressively away from

the sea

To answer my first hypothesis, I will be looking at figure

4, figure 7 and figure 8. Figure 4 shows a scatter graph of the results

collected at Studland, measuring the soil moisture in percentage. This graph,

however, does shows anomalies in my results around site 5, where water

percentage spikes to 60%, and around site 14, where water percentage drops to

25%. These may have been caused by tourists exploring the area, for example,

young children may by bringing buckets of water from the sea higher up the

beach and into the dunes where the soil is more absorbent, causing a spike in

the moisture, or people could be hiking along the back of the dune damaging and

eroding the organic matter that helps to retain the moisture, causing a drop-in

soil moisture. Looking at the trend line on this graph you can see clearly that

the line shows a positive gradient, meaning that this graph shows the soil

moisture increasing progressively away from the sea. This trend would suggest

that my prediction is correct, however the reliability of these results needs

to be tested. Hence figure 7, a spearman’s rank using the result collected

about soil moisture, using this statistical test I can see the probability that

my results did not happen by chance or coincidence. The spearman’s rank value

for this test calculated as 0.527. Using figure 8, the table of significance I

can see that these results had 95% significance. This means I can be 95% sure

that my hypothesis on soil moisture was correct, and I can accept my original

hypothesis.

Secondly, to answer my second hypothesis, I will be looking

at figure 5, figure 6 and figure 8. Figure 5 shows a scatter graph of the

results I collected at Studland, measuring the pH of the soil. This graph,

however shows an anomaly in my results around site 4, the pH drops to 4.40.

This may have been caused by storms and torrential rain, this may have weakened

the salinity and therefore alkalinity of the soil, or tourists walking along

the dunes may have eroded parts of the dune away, reducing salinity of the

ground by eroding away salt minerals. Looking at the trend line on this graph

you can see clearly that the line shows a negative gradient, meaning that this

graph shows the pH of the soil decreasing progressively away from the sea. This

trend would suggest that my prediction is correct, however the reliability of

these results needs to be tested. Hence figure 7, a spearman’s rank using the

results collected about pH of the soil, using this statistical test I can see

the probability that my results did not happen by chance or coincidence. The

spearman’s rank value for this test calculated as 0.629. Using figure 8, the

table of significance I can see that these results had 99% significance. This

means I can be 99% sure that my hypothesis on soil pH was correct, and I can

accept my original hypothesis.

Penultimately, to answer my third hypothesis, I will be

looking at figure 9, figure 10, figure 11 and figure 12. Figure 9 shows a

transect of Studland we studied, with bar graphs to show the vegetation present

at each site. These bar graphs show that the quadrat area we recorded is made

up of a wider variety of plants as you travel up the beach. For example, at

site 1, the area is made up of 100% bare sand whereas at site 14 the quadrat area

is made up of 20% gorse, 40% heather and 40% bell heather, looking at these

graphs and their progression, I would suggest that my hypothesis for this is

correct. Looking at figure 10, which are kite diagrams showing the distribution

of the and variety of vegetation along the transect. These diagrams also

support my hypothesis as they show that as you move along the transect the

variety and complexity of the plants increases. I can back up these resources

using a statistical test to see how accurate and reliable my results are. For

this I used Simpsons Diversity Index to test the diversity at each site. This

works by producing a number between 0 and 1, the nearer to one the higher the

diversity of the site. Figure 11 shows all my calculations for this test, and

how I obtained the result for each site, and figure 12 shows a table looking at

each result individually as well as a scatter graph, with a trend line to show

the distribution and overall progression of the Simpsons Index. This graph,

however, does show a couple of anomalies. These are shown at site 10, for

example, where the index drops to around 0.3, or at site 8 where it drops to

around 0.35. These may have been caused by tourists, walking along the dunes

and therefore trampling the vegetation and plants. This would mean that the

coverage of all the original plants may not be present, as more fragile plants

such as fern may have been wiped out from that particular area. Looking at the

trend, it shows a positive gradient, meaning that species diversity increases

progressively along the transect meaning percentage coverage does also. This

shows that my hypothesis on percentage vegetation cover was correct and I can

accept my original hypothesis.

Finally, to answer my fourth hypothesis, I will be looking

at figure 9. Figure 9 shows a to scale transect of the area we measured in

Studland, that shows the height and gradient of the dunes. The diagram shows

the height of the dunes gradually increasing along the transect, with a maximum

incline of +29°at site 7. This shows that my hypothesis is correct, and

dune height increases progressively away from the sea. This means I can accept

my original hypothesis.

Overall, the analysis of all my results and the tests I

carried out to support them have proved that all 4 of my original hypothesis are

correct and can be accepted. This will help me to answer my investigation title

of ‘How

the sand dune environment in Studland, Dorset changes progressively away from

the sea’ accurately with great reliability.