PHYSICAL FIELDWORK: How does the tree density and height vary in the Wyre Forest Flashcards
Wyre Forest
Why was this an appropriate question?
This links to the living world section of the GCSE specification looking at a case study of a UK ecosystem
Why was this an appropriate site?
- It’s local to school so it is easy to get there and back in a school day
- Accessible as the forest has footpaths
- Managed by the Forestry Commission which improves safety of the day as there is a visitors centre if help is needed
What are potential risks? How did you overcome these?
WEATHER -Heavy rainfall could lead to getting cold and hypothermia. Extreme heat could lead to sun burn. Therefore, I carried a waterproof in case of rain and sun tan lotion and a hat for the sun
SLIPS, TRIPS AND FALLS - I could twist an ankle or break a bone. Therefore, I behaved in a sensible manner and work appropriate, sturdy footwear
What were your primary fieldwork techniques?
- Tree height measurements
- Tree density measurements
- Environmental quality index
- Undergrowth cover survey
What were your secondary fieldwork techniques?
Why did you use an undergrowth cover survey? What is the downside of them?
- This will allow us to see how the undergrowth changes throughout the forest. This is a simple method that doesn’t require complicated or expensive equipment. It is also easy to replicate
- Man made objects may interrupt the sample, e.g. footpaths which would give non stereotypical data. Additionally, percentage of each type of vegetation is only estimated which may lead to inaccurate results
Why did you use a proportional bar graph? What is the downside of them?
- Proportional bars or divided bar charts split up rectangular bars to break the information down further. They are easy to view and compare data making it easier to draw conclusions.
- Only displays numerical data, sometimes there is an explanation behind the data, e.g. the survey included a footpath
What sampling technique did you use? Why? What is the downside of them?
STRATIFIED SAMPLING - Collecting data in an ordered or regular way. This reduces the potential for bias in the data. We will use this for the forest floor cover sampling every metre along a transect
- Man made objects may interrupt the sample, e.g. footpaths which would give non stereotypical data
Why did you use a tree density survey? What is the downside of them?
- This will allow us to see how dense the forest is in each area. Small distances between trees will mean the forest is denser. This is a simple method that doesn’t require complicated or expensive equipment. It is also easy to replicate
- It can be difficult to access trees that aren’t close to a footpath. Therefore, we aren’t measuring the true tree density in the middle of the forest
Why did you use a tree height survey? What is the downside of them?
- This allows us to estimate how long the trees have been growing for in each area. Taller trees are generally older. This is a simple method that doesn’t require complicated or expensive equipment. It is also easy to replicate
- It is important to be accurate with the angle and the use if the clinometer. This can be difficult with non-digital clinometers. It’s important to measure the height of the person
Why did you use a chloropleth map? What is the downside of them?
- Chloeopleths are maps that are coloured in to show value on a map. They clearly show patterns of where trees are most densely clustered
- Doesn’t always show the finer detail as it assumes the number of trees in some places
What conclusions did you draw in relation to the original investigation?
Overall there isn’t much of a trend to suggest a pattern. There is some evidence to suggest that our hypothesis is correct and that trees get taller and denser as you move away from the centre. This is due to trees being cut down to make space for the centre, play area, car park and footpaths. Trees further away are allowed to grow. However, this pattern is weak as the forestry commission manages the whole area. This means trees are selectively logged and replanted all over the forest.
How good were your methods at allowing you to collect data?
STRENGTHS:
- The methods allowed me to collect a range of data, using simple to use equipment
- All techniques were easy to replicate at each site and able to be conducted by GCSE students
LIMITATIONS:
- Additionally, calculating tree height using trigonometry is not very accurate and relies on accurate measurements of people’s height and the angle to the top of the tree
- Taking averages of undergrowth cover is quick, but not very accurate leading to some sites having more or less than 100% of ground cover
How good was your data at allowing you to come to a conclusion?
STRENGTHS:
- I have a range of information that will allow me to draw conclusions
- As multiple measurements were taken at each site of each technique an average could be taken. This allows any anomalies to be removed from the results
- I have a range of information that will allow me to draw conclusions regardless of weather or time of the year
LIMITATIONS:
- I could only survey the areas/trees directly close to the footpaths due to the high number of brambles so data is limited to the area closest to the path and possible not representative of the whole area
- I only had time to visit 4 sites in a forest that is over 9km^2 which means I can only draw valid conclusions for the small area that I visited
How would you improve or extend your investigation?
I could venture further off the footpaths, visiting in winter when the undergrowth will not be as dense due to the cold temperatures. Additionally, I would need to visit the forest on multiple occasions to survey a larger area, possibly collecting secondary data from the Forestry commission on tree height and density
