Pembrokeshire Flashcards
What are the 6 seral stages of primary succession and explain what happens at each
Migration - seeds arrive on the sand
Colonisation- start of plants flowering (pioneer species)
Establishment - the vegetation is more compact
Competition - pioneer plants begin to die out as equilibrium plants start to grow - fight for survival (high biodiversity)
Stabilisation - the biodiversity dips - equilibrium plants have taken over - pioneer plants mostly dead
Climax - no change - equilibrium dominantly with the environment
What is the salt marsh called?
Gann salt marsh
Where is gann salt marsh located?
South west wales, south west Pembrokeshire near Dale
How is the salt marsh sheltered?
By a peninsula of the Irish Sea
What is the aim of our investigation
To investigate changes in vegetation with increasing height up the Gann salt marsh
How did the salt marsh form?
Fresh water meets sea water, clay flocculates and is deposited
What is the null and alternate hypothesis
Null - there will be no change in vegetation with increasing height up the Gann salt marsh
Alternate - ther will be a change in vegetation with increasing height
What is the main road that runs through the location
B4327
What date did we go?
15/3/16
Why did we choose our location?
Accessible, SSSI site, secondary data AND primary data - could compare results, saltmarsh had no previous Occupation of vegetation , can see a directional change over time
What method of sampling did we use?
Stratified
What does stratified sampling mean
Interrupted transect belts where we physically saw a change (proportionate) so it is easier to see changes basically
Why did we choose stratified and not systematic
Quicker and easier
Explain our sample size
6 groups = 6 samples - each quadrat has 10 holes so 6 x 10 = 60 samples
What quadrat did we use and why?
Point quadrat because it was able to show the different layers of vegetation giving a specific pinpoint
What were the 2 methods of data collection ?
Vegetation sampling and height increase
How many interrupted belt transects?
8
What was the issue with our saltmarsh choice?
Human interference at pickle ridge - not a natural climax, instead had a plagioclimax meaning we couldn’t show all seral stages of primary succession
How would you answer a question asking for the method of vegetation sampling
How to do it, why you did what you did e.g. Stratified sampling, and point quadrat and then the limitations (small transect-representation, time of year plants are dead, human error and stratified bias system)
How did we record the data in the vegetation sampling method?
Used a dichtonumous key and imputed data into iPad which went into a system called ESRI aswell as recording the longitude and latitude to know where we are.
Why did we note our longitude and latitude
So that we could know exactly where we were along the saltmarsh
What type of data was gained by recording the species sampled?
Quantitative which is easy to analyse giving statistical significance
How would you explain the height increase method?
How we did it and the equipment, and why we did it e.g. The sample size to give an average height increase and the IBT which shows vegetation sample at each increasing height point and therefore age
Also limitations eg human error, equipment (optical block) stratified sampling - distance (hard to see that far )
Name all the equipment used in the height increase method
2 1m sticks, optical block,
What are the 7 sections that are asked about in the exam
Introduction, methodology, risk assessment, data analysis (spearmans rank and SDI), data interpretation (aim, hypothesis and results at each site), data presentation (kite diagram) and evaluation
What is spearmans rank and why did we use it?
Shows us the strength of the correlation between two variables (height and biodiversity) when applied to the critical value table it shows how significant our correlation is and whether our results are due to chance factors
What did our spearmans rank and critical value table show?
That there is a strong positive correlation and that there is less than 1% chance that our results are due to chance factors. Our spearmans tho value was 0.879. We compared it to 0.05 and then 0.01 and our value was still higher