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

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)

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!

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

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

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.

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.

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

Questions 1.What is a pioneer community? 2.Why are these plants able to grow on bare rock? 3.How does a thin layer of soil form on bare rock? 4.What happens when smaller plants die? 5.What is the name given to this event? 6.What is climax vegetation? 7.What does equilibrium mean?

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

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

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

A transect across a sand dune system... XY Reveals variations in relief and vegetation ………..

X Y A transect across a sand dune system

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

Embryo and Fore Dunes: the plants The plants which grow here have adaptations which allow them to grow in a difficult environment : Sea rocket high salt tolerance deep tap roots to obtain available moisture Frosted orache Saltwort Sea couch prostrate (low) habit to avoid strong winds Sandwort waxy leaves to retain moisture and withstand winds

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

Yellow Dunes: the plants Salt tolerant Thrives on being buried by sand Inrolled leaves to reduce moisture loss Long tap roots Underground rhizomes stabilise the sand Other plants such as Ragwort, Red fescue and Sand sedge begin to appear The dominant plant species is Marram grass:

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

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

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

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

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

Dune Heath / Woodland: the plants Human interference means that true mixed woodland climax vegetation is rarely seen on dune systems in the UK Most dune systems develop into a community of heathland, woody perennials (often spinous) and scattered trees Heather Sea buckthornHeather

Past paper handout 2008

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

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

Factors influencing dune stability People Soil Climate Slope Other vegetation 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 Climate: Windy – blows sad at plants Exposed – no shade or shelter Slope: Sand is mobile Some plants may get buried Other vegetation: Competition Not enough humus to support/ create different vegetation types

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

Yellow Dunes: the plants Salt tolerant Thrives on being buried by sand Inrolled leaves to reduce moisture loss Long tap roots Underground rhizomes stabilise the sand Other plants such as Ragwort, Red fescue and Sand sedge begin to appear The dominant plant species is Marram grass:

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

True or False 1.Humus content decreases as you go inland 2.Ph declines as you move inland 3.Plants are well sheltered on the Embryo dunes 4.Marran grass is found on the Yellow dunes 5.Dandelions are found on the Fore dunes 6.Sandwort can be found on the Embryo dunes 7.Salt content increases inland 8.Yellow dunes, Grey dunes and Mature dunes are all fixed dunes 9.At the climax stage plants are stable and relatively unchanging

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

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

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

Yellow Dunes: the plants Ragwort Marran Grass

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

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

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

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

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

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

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

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

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

Using the Core Higher Textbook Read pages Answer the following questions on page (b) 2(d) 2(g)

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.

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