Studland Heath is an area of Special Scientific Interest (SSI). Succession is demonstrated in the area.
There are two sand dunes, with the one closer the shore named First Sand Dune (S1) and the other one further away named Second Sand Dune (S2) in this analysis. Two crucial factors for sand dune formation are adequate supply of sand and strong wind. Waves deposited sand inshore at high tides. Sand is dried up during low tides. Wind blows sand further up the beach and finally deposits them in the leeward side. Accumulation of sand forms sand dunes.Yellow Dune Community is found in S1 while Grey Dune Community is found in S2 due to differences in physical conditions.
S1 is a harsh environment for plants to grow, due to unstable sand, extreme temperature, high salinity and low water content. Pioneer plants, mainly xerophytes (e.g. Marram Grass, Sea Holly, Sea Spurge) are therefore found in this community owing to better adaptations. On the other hand, the conditions at S2 (Acidic Grey Dune Community) is better. Despite of the shallow and fragile soil and low water content, the area is more sheltered and stable than S1. A darker soil colour indicates a higher nutrition level. Nutrients built up as pioneer plants die and decay.
Plants usually found in this community are ling Heather, sand sedges, gorse, etc.The null hypothesis for this investigation is set up based on the environmental differences between S1 and S2, and it is: There is no difference in the distribution of marram grass and ling heather on the windward slope of S1 and S2. Only windward slopes are taken into account as they share similar physical conditions (e.g. wind speed). Collection of Data Field study was carried out on 30th May 2004 and Studland Heath. Sampling method used was interrupted belt transects. A measuring tape was laid out perpendicular to the shore.
A 0.5X0.5m quadrat was placed to the right of the measuring tape at 20m intervals. Species laid within the quadrat was identified with their percentage cover recorded.Wind speed, soil pH, soil temperature and angle of inclination were also recorded at every site. As the difference between the averages (106.7%) is greater than 2 X S.E.
(9.38%), the results are significant, i.e. there is a significant difference between the distribution of marram grass and ling heather in Studland Heath on 30th May 04. The null hypothesis is therefore rejected. There is a significant difference in the distribution of marram grass and ling heather on the windward slope of S1 and S2.Evaluation Problems in sampling: 1. Processed data used in the analysis includes data collected by different groups and different sites.
However, groups are not working parallel to each other, thus the data may actually be collected at different sites. 2. It is not always possible to collect data in 20m interval due to the landscape. Groups need to make adjustment in various situations, e.g. when approaching the top of the dune. 3.
It is difficult to identify different species due to lack of experience. Different species may also grow together, overlapping each other, thus making it more difficult to be identified.4.
Succession in Studland Heath maybe deflected by human activities, e.g. work has been done to prevent the community develops into woodland. This may affect our assumption that the succession is only affected my physical factors.
5. Percentage cover of species is recorded instead of the number of plants. Percentage cover maybe affected by various factors, e.g. size of plants together with number of species. Thus percentage cover may not be a good representation of occurrence of species in different sites.Overcoming the problems: 1.
A compass can be used to check the direction of groups and ensure all of them are perpendicular to the shore. This solves problem 1. 2.
By classifying the species into larger groups, it makes identifying the species easier and helps solving problem 3. 3. A more throughout sampling should be done to collect a wider range of data, e.g.
collect the data in 10m interval. This may minimise the effect of errors in technique. 4. Sampling should be repeated on a day with similar physical conditions to improve its reliability.