1. Plant successions from bare ground are known as priseres
Plant successions from bare ground are known as priseres. There are four main types of priseres:  
Xerosere (Dry)
Lithoseres
where the plants colonise bare rock
e.g. after glacial retreat, Snowdonia or a rocky shore, Oxwich Point, Gower or a newly created volcanic island (e.g. Surtsey, Iceland)
Psammosere
where plants colonise coastal sand dunes
e.g. The south Gower - Oxwich Bay.
Hydrosere (Wet)
Hydroseres
where the plants colonise fresh water, as at a pond margin
e.g. Llanfihangel Gobion, Monmouthshire - ox-bow lakes
Haloseres
where plants colonise salt marshes and sea estuaries
e.g. The North shore of the Gower, Lanrhidian salt marsh
Priseres
K.I 4

2. Prisere : complete succession from initial inorganic (1) too wet/dry conditions to climatic climax vegetation (5?). 5? 1
e.g. Psammosere

3. Initial conditions either
too wet
Or too dry
Or too alternating wet / dry
Possibly with salt
Therefore only a few plants can tolerate these harsh conditions
No soil
BARE INORGANIC SURFACE
Mosses and lichens COLONISERS
PIONEER COMMUNITY

4. Climax vegetation is the vegetation which establishes itself on a given site for given climatic conditions (in the absence of human action) after a long time
Climatic climax vegetation
Witham Woods Oxfordshire

5. Plagioclimax subclimax (after deforestation, ploughing, burning
THE POLYCLIMAX THEORY
New inorganic (non-vegetated surface) 4 1 3
Secondary succession
Primary succession
Climax Vegetation 2 1
Primary succession
natural interruptions in primary succession
Retrogressive succession due to disturbance (natural or human)
Secondary succession
Biotic subclimax 2 2 3
Edaphic (soil) subclimax 4

6. Seral Stages – temporary stages which develop over time leading to plant succession1 2 3 4 5
Time goes by (100s of years)
or different spatial positions at one time

7. Subclimax
An arresting factor halts development
e.g. biotic (rabbits, goats, sheep: graze the land and prevent tree growth)
e.g. edaphic (salty soil – hinders tree growth)
Birch tree subclimax

8. Plagioclimax

9. Primary Succcession on heather moorlands (U.K.)
Post glacial recolonisation in the lower hills
Mosses, lichens,
hardy grasses
Grasses, herbs, some heather
Tall shrubs e.g birch
Pine, hazel
Oak forest

10. From Oak Trees to Heather Moorland
After the Ice Age the primary succession to heather moorland occurred.
Humans cleared the trees for farming. The soils lost became leached and lost their fertility. The acid soils did suit heather.
Young shoots of heather are ideal for sheep grazing and the moorlands are used for hill farming. The grazing prevented the regrowth of shrubs and trees.
Periodic burning (muirburn) removes old wood, releases nutrients and encourages new shoots. The heather is maintained as a plagioclimax.

11. Improved pasture or arable farmland
PLAGIOCLIMAX
Oak forest
Deflection by humans : cutting, burning, grazing
SHRUBBY HEATH
Poor drainage
burning
Liming, fertiliser
overgrazing
Blanket bog
Heather moorland
Improved pasture or arable farmland
Grassy heaths