Prediction:
I predict that grass will be the most dominant species in each of our quadrats.
Results:
We gathered our results in a table, shown below. We used the dafor scale to estimate the plants accurately.
Key
D dominant
A abundant
F frequent
O occasional
R rare
- none at all
Graph:
I have put my results into a graph so that my findings are easier to understand, and any trends or patterns will stand out. (See attachment 1).
What I have found out:
I have found out that my previous prediction was correct, grass was the most dominant species on the school field. Clover, plantain, and dandelions also appeared frequently.
The reason that grass is so dominant is because of the way it grows. Grass grows from the base of the stem so when the top of the plant is cut off it can survive and will grow again, unlike most other plants which grow from the apical bud, which grows off the stem, usually at the top of the plant. When the grass is cut, this bud will be cut off, disabling the plant from growing. As the leaves on a plant would usually be cut off aswell, the plant is unable to photosynthesise and therefore cannot survive and grow again.
However, clover, plantain, dandelions, buttercups and daisies were also existent on the school field, so they must have their own ways of survival…
Clover
Clover grows very close to the ground, and although small, each plant has many leaves so is able to collect enough sunlight to photosynthesise. Because they live close to the ground they avoid being cut when the field is mowed.
Plantain
The leaves of a plantain have a large surface area, so that even though they grow close to the ground, they collect enough sunlight to photosynthesise. They grow almost flat to the ground, so are not reached by the lawnmower when the grass is cut.
Dandelions & Daisies
It’s the same for dandelions and daisies. They grow very close to the ground so are able to avoid being cut. There were not many daisies on the school field, probably because their leaves are so small they will not be able to collect enough sunlight to survive, with being so close to the ground and covered by other plants.
Buttercups
Although we didn’t find many buttercups on the field, they are adapted to living there. We found them ‘crawling’ along the ground, instead of growing straight up, so they can avoid being cut, and still collect the sunlight they need through their large leaves which crawl along the ground.
Conditions on the school field
When we carried out our investigation, the ground was quite dry and had recently been cut. The field was not damaged or muddy, as the main use of the field up to this time had been for athletics, and children walking on the field at lunchtimes, which did not wear the grass away, whereas if we had carried out the investigation when it had been raining, when the grass hadn’t been cut or when the field had been used for rugby and football during the winter, the results might have been very different. Factors like these could affect which plant types can grow and survive there.
Trends and patterns in our results
I noticed a few trends whilst looking at my results. The most obvious one is that grass is dominant in every quadrat. I have explained previously the reasons for this. I also noticed that in the 3 quadrats I tested which had lines of the athletic track running through them(6,7 & 15), plantain was abundant. This could just be a coincidence but I think the reason may be because the grass has been burnt away where the line is, there is more room for other plants such as plantain to grow. I also noticed that buttercups and daisies were never found in the same quadrat together, though I can think of no apparent reason for this other than pure coincidence.
Evaluation:
How reliable were my results?
I think my results are quite reliable, although we couldn’t follow all the rules of making the experiment a fair test. We had to study the quadrats over two separate days, due to lack of time, so the grass had had chance to grow. Even though the conditions were similar, this could affect the reliability of my results. Also, as we used the DAFOR scale to estimate, the results are a rough guide. The results would have been more accurate if we had had the time to count every individual plant.
Am I confident about my findings?
Considering the small space of time we had to do the experiment in, and the lack of scientific equipment we could have used to help us, I am quite confident that our results show a realistic guide to the amount of plants growing on the field.
Is there enough to base conclusions on?
We did study 20 areas along a belt transect on the field. I think it gives a realistic idea, but to know for sure we would have to research the entire field.
Were there any anomalous results?
I am not aware of any results that don’t fit in with the rest. I believe the results are fairly accurate, and fit in well with each other.
How could I improve what I did?
There are a number of things we could have done to improve our investigation.
* If we had more time, we should have studied all the quadrats on the same day, to ensure the conditions on the field were the same.
* We could have used better quadrats, as the ones we used may not have been entirely accurate, as we made them ourselves using a metre stick and string. Our areas therefore may have varied in shape, making the test unfair.
* We could have used a more accurate way of estimating plant numbers by counting each plant individually. Unfortunately this would have been very complicated and time consuming.
* We could have researched more areas, to ensure that we had been thorough and our results were accurate.
Extension work
If we wanted to take our investigation further, there are many things we could do. We could:
* Research the entire field. If we did this we would get a much more accurate idea of plant numbers, as even the smallest areas would be studied.
* We could do the investigation in different seasons, as the field is used for different things throughout the year. We could do this to see if the use of the field, and change in weather conditions affects plant growth.
* We could study the soil type, and compare the plant growth to that of another field with a different soil type, to see if soil type affects plant growth.
* We could leave part of the field to grow, to compare the species growing in long grass to those growing in short grass.
Emma Gascoigne11T
