Null hypothesis
There would be about the same number of types of fauna species in both the upper shore and the middle shore.
Equipment list
- wellington
- random number table
- 4 measuring tapes
- quadrat
- pictures of different fauna
Method of sampling
- I am going to start with the upper shore.
- First of all, I will throw a stone randomly onto the sky.
-
Secondly I will determine the centre of a 100m2 square at where the stone drops and finally stops.
- Next I will use four measuring tapes, which all show 0 to10 m, as the edge of the square.
- I will name one corner as the start.
- After that, I will find 2 random number from a random number table.
- I will then take the first number as the distance along the length of the square from the starting point and the second number as the distance along the width of the square from the start
- I will extend the two lines and place the quadrat at the point where those lines meet
- Afterwards I will record the number of fauna species and also the number of individual species occur in that quadrat
- Next I will repeat steps 6 – 9 for 9 more times to get 10 samples
- Finally I will repeat the whole process for the upper shore
Control
In order to be fair and square, several controls have to be taken into account. So samplings will have to be carried out at a particular time (at 3:30pm on the Wednesday, 17th of July, 2002) with the same tidal level (the mid-tidal level) on the same shore (Port Eynon). Attachment 1, the map of Port Eynon.
Safety
Safety is one of the biggest issues when doing investigation, so we must be aware before actually doing it. For example, I can imagine that the rocky shore would be very slippery even with Wellington, so we should be extremely careful not be hurt ourselves.
Statistical analysis
In comparing the ecological diversity, diversity can be quantified by calculating the diversity index. D = where D = Diversity index
N = Total number of individual organisms
n = Number of individuals per species
= The sum of
For the upper shore
Number of limpets = 12 + 11 + 7 + 8 + 1 + 6 + 7 + 6 + 5 + 5
= 68
Number of small periwinkle = 1 + 2 + 1
= 4
Number of rough periwinkle = 1 + 2 + 1
= 4
Number of acorn barnicle = 90 + 80 + 120 + 65 + 75 + 70 + 20 + 10 + 50 + 100
= 680
Total number of individual organisms = 68 + 4 + 4 + 680
= 756
D =
=
= 1.22 (to 3 s.f)
For the middle shore
Number of limpets = 13 + 12 + 18 + 10 + 9 + 11 + 10 + 17 + 13 + 10
= 123
Number of small periwinkle = 2 + 4 + 2 + 5 + 7 + 4 + 4 + 4 + 6 + 8
= 46
Number of rough periwinkle = 14 + 19 + 21 + 15 + 7 +13 + 7 + 8 + 7 + 11
= 122
Number of acorn barnicle = 130 + 200 + 170 + 260 + 270 + 320 + 290 + 350 + 410 + 120
= 2520
Total number of individual organisms = 123 + 46 + 122 + 2520
= 2811
D =
=
= 1.24 (to 3 s.f)
Interpretation
For ecological diversity, as the diversity of species in a particular area increases so does its diversity index. But from the statistical analysis that I have just done, I can see that the diversity index in the upper shore was 1.22 and was 1.24 in the middle shore. There is not much difference between those two. Both areas have almost the same diversity index.
So there is enough evidence to support the null hypothesis that there are about the same number of types of fauna species in both middle and upper shore.
Apart from comparing the diversity index in different shores, what I can notice is that the total number of individual organisms is greater in the middle shore than the upper shore. This can just back up what I have said in the hypothesis before. As the middle shore is covered by sea water for a longer period of time than the upper shore, desiccation, temperature and humidity changes are not as serious and this allow more organisms to live in for better live.
Evaluation
When I come to evaluating evidence and procedure, I found out that t have come across a few problems or limitations and they could have affected the result I obtained. They are:
- There are lots of rocky pools in the area, so sometimes I have had to reject some particular points chosen by random number table. This made my results not completely random.
- Places that I have chosen in both shores were a bit lower than the rest of the corresponding shores, which means there were rather lots of seaweed covering the rocks than usual. And this made it hard for me to count the types and number of species in each quadrat.
- I have move further left for the middle shore compare to the upper shore because of the place being occupied by the others. This might have slight effect on my results as the environment changed a little bit.
- It was hard to define organisms. e.g. there are four types of periwinkle and some of them are quite similar and this could have affected the diversity index that I got.
Overall there are no anomalies in results.
End