Rocky Shore Investigation

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Rocky Shore Investigation Null Hypothesis: There is no pattern to the distribution of organisms over a rocky shore. Variables: Factors that affect the distribution of organisms over an area of shoreline are: · The depth of water which may cover an organism at high tide. · How resistant an organism in the littoral zone is to dessication. · How efficiently an organism can conserve water. · The proximity and availability of nutrition. Stations ======== I think that stations 1 – 4 are in the sub-littoral zone of the rocky shore. Stations 5 – 12 are in the mid-littoral zone. Stations 13 – 15 are in the splash zone. I know this through observation on the day, the amount of rock pools and their depth etc. Consequently the splash zone had no rock pools, the mid-littoral zone had some, but these were not very deep, the sub-littoral zone was very close to the sea and was almost all rock pools with lots of slippery seaweed. My results show that this was mainly Fucus vesiculosus (Bladdder Wrack). Analysis of Results: ==================== Animals ------- There are several clear trends in my results, the clearest of these being the limpet (Patella vulgata). The majority of limpets were situated mainly in the mid-littoral zone and splash zone. They had a peak at station 12 of 31 limpets. Their number slowly built up to this peak from 1 limpet at station 4 to 33 limpets at station 12. The limpets also petered out in numbers after station 12, to go 13 to 6 to 0. This tells me that they do not want to be exposed for that long between tides. However, station 12 still has a ... ... middle of paper ... ...rocky shore. We could have done this by placing two measuring poles at the required points on the beach and then using a field level device, such as an Abney level, which consists of a sighting device and a spirit level. This would have produced two heights which when subtracted from eachother would have produced height increase. We could also have improved the investigation by checking more thoroughly in the quadrats and by spending more time learning what the species subtle differences were. We could have ensured that the groups we took data from for the averages had spent a decent amount of time on the investigation and had not rushed it. There were many aspects of the investigation that could have flawed the results however overall I think that the practical still reliably rejected my null hypothesis.
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