Different species of algae are distributed in specific zones on the shore according to their characteristics, this is called zonation. For our investigation we are analysing the link between these characteristics and the zones in which each species inhabits. The main algal species present are; Pelvetia canaliculata and Fucus spiralis (Upper shore), Ascophyllum nodosum and Fucus vesiculosus (Middle shore), and Fucus serratus and Laminaria digitata (Lower shore).
Pelvetia canaliculata – Small in size, frond (3-5cm in length, Small SA), grows in clumps on bare rock.
- edge of frond = raised (unique to Pelvetia)
Fucus spiralis – Small in size, frond (twisted 8-10cm) – wider than pelvetia
Ascophyllum nodosum – Single air bladders on frond(Long+Narrow)-Can grow to 1m in length (Adult)
- Deviation from trend (1m long frond)
Fucus vesiculosus – Paired air bladders, and again wider frond than Ascophyllum
Fucus serratus- ‘Saw-tooth’ margin, inc. SA (Wider frond than vesiculosus)
Laminaria digitata- Huge in size – can grow to 2m in length. Has splits in frond. LWM +Below –Cons.
- Dipping in water
A1 – 2
There are a range of ecological factors that influence algal zonation, these are;
Ability to withstand desiccation
*MAKE A LINK TO WHERE THEY INHABIT(Are found)*
EG. ..... And therefore (Insert Seaweed) are found on (Upper/Middle/Lower) Shore.
EG. .... This is why (Insert Seaweed) are found on (Upper/Middle/Lower) Shore.
A1 – 3
‘Desiccation tolerance’ is the factor that is most likely to explain the distribution of the species and will be the factor that will be investigated.
Most tolerant live on upper shore (Pelvetia canaliculata and Fucus spiralis) WHY?
Least tolerant live on lower shore (Fucus serratus and Laminaria digitata) WHY?
Ascophyllum nodosum and Fucus vesiculosus...
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