Learning Objectives Understand ecological successions Success Criteria

1. Learning Objectives • Understand ecological successions • Success Criteria • Describe and explain the meaning and the succession of a PSAMMOSERE 1

2. Plant succession Plant succession is the development of plants. This can take place in many areas such as • Fresh water (hydosere) • Bare rock (lithosere) • Sand dunes (psammoseres)

3. Ecological succession During succession the ecosystem goes through a series of stages. Each stage is called a seral stage and the complete series of plant communities resulting from the process of succession is called a SERE!

4. Psammosere A psammosere is a plant succession on a sand dune. It consists of a series of dry sandy ridges interspaced with wet hollows called slacks. Sand dunes become stable when plant life develops

5. Three main stages Pioneer stage Seeds are blown in by the wind or washed in by the sea. Rooting conditions are poor due to drought, strong winds and salty sea waster immersion and alkali conditions created by seashells

6. Three main stages Building stage Plants trap sand and grown with in binding together the sand with their roots. The humus created by decaying pioneer plants creates more fertile conditions.

7. Three main stages Climax stage Taller plants (like trees) and more complex species can now grow, Plants from earlier stages die out due to competition for light and water.

8. Climax Vegetation Final stage of plant succession Relatively stable and self sustaining Does not change High highest biomass/ variety of species Vegetation in harmony/ equilibrium with environment Scottish examples – Oak, Pine, Birch woodlands

9. Questions • What is a pioneer community? • Why are these plants able to grow on bare rock? • How does a thin layer of soil form on bare rock? • What happens when smaller plants die? • What is the name given to this event? • What is climax vegetation? • What does equilibrium mean?

10. Learning Objectives • Understand ecological successions • Success Criteria • Describe and explain the formation of a dune system 2

11. Growing a Sand Dune system • A plentiful supply of sand • Strong winds to transport sand particles through saltation (bouncing and hopping of sand on surface) • An obstacle to trap the sand, usually it’s a plant or a piece of seaweed that’s located on the tide or strand line

12. An aerial view of a sand dune system youngest dunes oldest dunes

13. A transect across a sand dune system... X Y Reveals variations in relief and vegetation ………..

14. A transect across a sand dune system Y X

17. Embryo and Fore Dunes: the environment on-shore winds high water mark seaweed deposits humus poor water retention sand builds up against pioneer plants transient dunes

18. Yellow Dunes: the environment above the level of high tides ‘Soil’ slightly less alkaline and more water retentive Some humus forming reduced wind speeds Surface continually blown away and replenished with fresh sand

19. Grey Dunes: the environment sheltered by higher, seaward dunes lower pH little mobile sand higher humus content sand no longer accumulating a more closed vegetation community in which marram grass is no longer able to compete

20. Dune Slacks: the environment occur in low lying hollows between dune ridges relief intersects the water table soil acidic water table high – especially in winter

21. Dune Heath/Woodland: the environment well sheltered from winds acidic soil nutrient rich soil has high organic matter content

22. Past paper handout 2008

23. Learning Objectives • Understand ecological successions • Success Criteria • Describe how plants have adapted in dune systems 3

24. Vocab Xerophytic – plants which are water resistant Hydrophytic – plants which are water tolerant Halophitic – Salt resistant Rhizomes – long roots/ stems

25. Factors influencing dune stability Slope: Sand is mobile Some plants may get buried Climate: Windy – blows sad at plants Exposed – no shade or shelter People: People walk on dunes and trample plants Soil: It is tidal so is never 100 % dry or 100% wet Lack of organic content so less nutrients Alkaline soils– sea shells Saline soils – salty water Drainage is too good – can be a lack of water Other vegetation: Competition Not enough humus to support/ create different vegetation types People Soil Climate Slope Other vegetation

26. Marram Grass Xerophytic (drought resistant) Long and sharp to prevent animals eating it Long rhizomes (underground stems) stabilise the dune/ bind sand together Rhizomes also reach underground for water to deep water table Curled up shape of grass reduces evapotranspiration Grows on bare soils with little competition Fast growing 1m per year

29. Learning Objectives • Understand ecological successions • Success Criteria • Identify plant species along a psammosere transect • Describe how plants have adapted along a psammosere transect

30. True or False • Humus content decreases as you go inland • Ph declines as you move inland • Plants are well sheltered on the Embryo dunes • Marran grass is found on the Yellow dunes • Dandelions are found on the Fore dunes • Sandwort can be found on the Embryo dunes • Salt content increases inland • Yellow dunes, Grey dunes and Mature dunes are all fixed dunes • At the climax stage plants are stable and relatively unchanging

31. Zone 1: Embryo and Fore dunes • Sand is poor in nutrients and is very dry • They are resistant to occasional immersion in water and are able to withstand high winds. • Plants that grow here have lateral roots and underground stems • Low lying to avoid strong winds • High salt tolerance • Waxy leaves to retain moisture and withstand winds • Alkaline with no humus

32. Embryo and Fore Dunes: the plants Sandwort Saltwort Sea rocket Sea couch

33. Zone 2: Yellow Dunes • Marram grass becomes the dominant plant • Its RHYZOMES (long creeping underground stems) help to bind deposited sand and reach water table • Leaves curl up in order to retain moisture • Marram can align itself with prevailing wind to • reduce moisture loss • Marram grows quickly (~1 metre/ year) to keep above the sand. • Salt tolerant

34. Yellow Dunes: the plants Marran Grass Ragwort

35. Zone 3: Gey Dunes and Slacks • Increased shelter + damper soil = higher species diversity • Shelter restricts supply of sand • Increased humus content • Vegetation cover now complete • Marram becomes more sparse • On Slacks, water table is near surface encouraging plants which prefer damp conditions

36. • marram becomes more sparse • surface lichens give ‘grey’ appearance Older grey dunes may have extensive covering of lichens and heather Grey Dunes: the plants • higher species diversity • mainly perennials

37. Dune Slacks: the plants The community which develops here comprises moisture-loving plants commonly found in many fresh water wetland areas e.g. Flag iris rushes Bog cotton Reeds

38. Zone 4: woodland/ grassland • Taller species indicate a deeper and wetter soil.

39. Dune Heath / Woodland: the plants Human interference means that true mixed woodland climax vegetation is rarely seen on dune systems in the UK Scots Pine Heather Heather

40. Learning Objectives • Understand ecological successions • Success Criteria • Explain fully what is meant by climax vegetation • Explain the plant succession in a sand dune

41. Explain what is meant by the term “Climax vegetation”?. • What is the question asking you to do? • Structure • What is important • Key words • Plant types 4 marks

42. Explain what is meant by the term “Climax vegetation”?. • Final stage/ stage of maturity = ecosystem is relatively unchanging and biomass is at a maximum • Dynamic equilibrium -maintains overall stability despite continuous small changes. • Progression – pioneers are displaced as conditions change • Plants compete for water, nutrients and space • Species such as scots pine and oak become dominant 4 marks

43. In your teams ……… • With the aid of a diagram describe AND explain the plant succession in a sand dune habitat. • You may wish to think about…… • Succession • Plant type • Conditions • Adaptations You have 20 minutes

44. Using the Core Higher Textbook.... • Read pages 152-155 • Answer the following questions on page 173-174 • 2(b) • 2(d) • 2(g)

45. Describe and Explain the changes in vegetation as you move inland from the coast. What is the question asking you to do???? Give the name of a type of vegetation in the pioneer stage and say how it has adapted to that environment and do the same for each stage.

46. What do you need to mention ……… • Each stage – from strandline to Woodland • Conditions • Humus content • Salt content • Ph • Shelter • Plant type • Adaptations