The document discusses succession and zonation in the Pyrenees. It describes how climate determines biome distribution, with forests found at higher elevations receiving more precipitation. In the Corbieres region of the Pyrenees, grasslands are the natural climax below 100m, forests above 1200m, and garigue shrubland forms a transitional zone between them. However, human farming activities have extended the range of the garigue biome into the forest zone.

1. Topic 2.4: Biomes, Zonation and Succession
Topic 2: Ecosystems and Ecology

2. Topic 2.4: Biomes, Zonation and Succession
Topic 2: Ecosystems and Ecology

3. Topic 2.4: Biomes, Zonation and Succession
Topic 2: Ecosystems and Ecology

4. Topic 2.4: Biomes, Zonation and Succession
Topic 2: Ecosystems and Ecology
Succession and Zonation in the Pyrenees

5. Topic 2.4: Biomes, Zonation and Succession
Topic 2: Ecosystems and Ecology
Part 1- Developing the context: Biomes, Zones and Habitat
distribution

6. Topic 2.4: Biomes, Zonation and Succession
Topic 2: Ecosystems and Ecology
Succession and Zonation in the Pyrenees
Part 1- Developing the context: Biomes, Zones and Habitat
distribution

7. Climate determines the type of biome in a given area, although individual ecosystems may vary due to many local abiotic and
biotic factors.
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Main ideas

8. Climate determines the type of biome in a given area, although individual ecosystems may vary due to many local abiotic and
biotic factors.
Succession leads to climax communities that may vary due to random events and interactions over time. This leads to a
pattern of alternative stable states for a given ecosystem.
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Main ideas

9. Climate determines the type of biome in a given area, although individual ecosystems may vary due to many local abiotic and
biotic factors.
Succession leads to climax communities that may vary due to random events and interactions over time. This leads to a
pattern of alternative stable states for a given ecosystem.
Ecosystem stability, succession and biodiversity are intrinsically linked.
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Main ideas

10. France
Pyrenees
The Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Found in the Pyrenees
Foothills of the Haute (High) Pyrenees

11. The Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Corbieres
France
Pyrenees
Found in the Pyrenees
Foothills of the Haute (High) Pyrenees

12. The Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Corbieres
France
Pyrenees
Found in the Pyrenees
Foothills of the Haute (High) Pyrenees
Patch work of fields and woodland
Farmed since Roman times

13. The Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Home to the Garigue community

14. The Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Home to the Garigue community

15. “Garigue is more or less open shrub community, usually about 50cm high, and rarely growing
above 1m. The dominant dwarf shrubs are often widely spaced, with a considerable amount of
bare, stoney ground between the clumps of shrubs, which, in the hot and very dry summers, gives
the vegetation a very parched appearance. Many species are aromatic, and have small dry
leathery leaves which often curl up in the summer, thus reducing transpiration loss. Some
shrublets are chemically unpalatable to grazing animals, others are very spiny and are thus
protected”
Polunin and Walters (1985)
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
What is Garigue?

16. Community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

17. Community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

18. Community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

19. Community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

20. Community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

21. Community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

22. Zonation
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Garigue forms a transitional zone
between Forest and Grassland biomes
in the Mediterranean

23. Forest
Garigue
Grassland

24. Formation
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Clearance of the forest for fuel and
grazing by livestock maintains the
Garigue as a semi natural Climax
community

25. Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

26. Zone where evergreen and
deciduous oak are the natural
climax community
Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

27. Zone where evergreen and
deciduous oak are the natural
climax community
Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

28. Zone where evergreen and
deciduous oak are the natural
climax community
Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
FOREST BIOME

29. Zone where evergreen and
deciduous oak are the natural
climax community
Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
FOREST BIOME
Zone where dry Mediterranean
grassland is a natural climax
community

30. Zone where evergreen and
deciduous oak are the natural
climax community
Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
FOREST BIOME
Zone where dry Mediterranean
grassland is a natural climax
community
GRASSLAND BIOME

31. Zone where evergreen and
deciduous oak are the natural
climax community
Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
FOREST BIOME
Zone where dry Mediterranean
grassland is a natural climax
community
GRASSLAND BIOME

32. Zone where evergreen and
deciduous oak are the natural
climax community
Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
FOREST BIOME
Zone where dry Mediterranean
grassland is a natural climax
community
GRASSLAND BIOME
Zone where Garigue forms the
natural transition between Forest
and Grassland Biomes

33. Zone where evergreen and
deciduous oak are the natural
climax community
Zonation in the Corbieres
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
FOREST BIOME
Zone where dry Mediterranean
grassland is a natural climax
community
GRASSLAND BIOME
Actual zone where Garigue
forms the natural transition
between Forest and Grassland
Biomes because of the influence
of man
FARMING

34. Garigue forms an transitional zone between zones of grassland and forest in the Corbiere range
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Part 1 Summary:

35. Garigue forms an transitional zone between zones of grassland and forest in the Corbiere range
Mediterranean grassland biome is a natural climax community to about 100m or higher where local
conditions allow
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Part 1 Summary:

36. Garigue forms an transitional zone between zones of grassland and forest in the Corbiere range
Mediterranean grassland biome is a natural climax community to about 100m or higher where local
conditions allow
Mediterranean mixed evergreen and deciduous Oak forest biome forms the natural climax
community from sea level to around 1200m
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Part 1 Summary:

37. Garigue forms an transitional zone between zones of grassland and forest in the Corbiere range
Mediterranean grassland biome is a natural climax community to about 100m or higher where local
conditions allow
Mediterranean mixed evergreen and deciduous Oak forest biome forms the natural climax
community from sea level to around 1200m
Distribution of Grassland and Forest communities are controlled by precipitation - where
precipitation is higher forest biome forms.
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Part 1 Summary:

38. Garigue distribution has been extended into the forest zone, through human activity - farming
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Part 1 Summary:

39. Topic 2.4: Biomes, Zonation and Succession
Topic 2: Ecosystems and Ecology
Part 2- Why is the Garigue community where it is?

40. Topic 2.4: Biomes, Zonation and Succession
Topic 2: Ecosystems and Ecology
Succession and Zonation in the Pyrenees
Part 2- Why is the Garigue community where it is?

41. Abiotic factors

42. Climate
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Data extracted from https://en.climate-data.org/europe/france/languedoc-roussillon/lezignan-corbieres-66328/

43. Climate
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and SuccessionTemperature(°C)
0
5
10
15
20
25
30
January
February
March
April
May
June
July
August
September
October
November
December
Avg. Temperature (°C) Min.. Temperature (°C)
Max. Temperature (°C)
Data extracted from https://en.climate-data.org/europe/france/languedoc-roussillon/lezignan-corbieres-66328/

44. Climate
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and SuccessionTemperature(°C)
0
5
10
15
20
25
30
January
February
March
April
May
June
July
August
September
October
November
December
Avg. Temperature (°C) Min.. Temperature (°C)
Max. Temperature (°C)
Precipitation(mm)
0
20
40
60
80
100
January
February
March
April
May
June
July
August
September
October
November
December
Data extracted from https://en.climate-data.org/europe/france/languedoc-roussillon/lezignan-corbieres-66328/

45. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Data extracted from https://en.climate-data.org/europe/france/languedoc-roussillon/lezignan-corbieres-66328/ https://
en.climate-data.org/europe/france/aquitaine/saint-jean-pied-de-port-185285/
Avg.Temperature(°C)
0
5
10
15
20
25
January
February
March
April
May
June
July
August
September
October
November
December
LÉZIGNAN-CORBIÈRES SAINT-JEAN-PIED-DE-PORT
Precipitation/Rainfall(mm)
0
50
100
150
200
250
January
February
March
April
May
June
July
August
September
October
November
December
LÉZIGNAN-CORBIÈRES SAINT-JEAN-PIED-DE-PORT
Climate Factors

46. Tramontane and Cers winds
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

47. Tramontane and Cers winds
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

48. Tramontane and Cers winds
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

49. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

50. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Primary Succession

51. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Primary Succession
Bare rock left after
the retreat of a glacier

52. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Primary Succession
Bare rock left after
the retreat of a glacier
In time mosses and lichens
start to colonise the rock
As they die organic mater
is added to weathered rock
particles making simplesoils

53. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Primary Succession
Bare rock left after
the retreat of a glacier
In time mosses and lichens
start to colonise the rock
As they die organic mater
is added to weathered rock
particles making simplesoils
As the soils develop grasses
and small herbaceous plants
start to grow
More organic mater is added
and roots of plants aid break up
of rock material

54. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Primary Succession
Bare rock left after
the retreat of a glacier
In time mosses and lichens
start to colonise the rock
As they die organic mater
is added to weathered rock
particles making simplesoils
As the soils develop grasses
and small herbaceous plants
start to grow
More organic mater is added
and roots of plants aid break up
of rock material
Deeper soils hold more
water.Small shrubs colonise
these better soils
Nutrient availability increases
More root action

55. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Primary Succession
Bare rock left after
the retreat of a glacier
In time mosses and lichens
start to colonise the rock
As they die organic mater
is added to weathered rock
particles making simplesoils
As the soils develop grasses
and small herbaceous plants
start to grow
More organic mater is added
and roots of plants aid break up
of rock material
Deeper soils hold more
water.Small shrubs colonise
these better soils
Nutrient availability increases
More root action
Eventually trees establish
leading to the development
of a climax community on
mature soils

56. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Primary Succession
Bare rock left after
the retreat of a glacier
In time mosses and lichens
start to colonise the rock
As they die organic mater
is added to weathered rock
particles making simplesoils
As the soils develop grasses
and small herbaceous plants
start to grow
More organic mater is added
and roots of plants aid break up
of rock material
Deeper soils hold more
water.Small shrubs colonise
these better soils
Nutrient availability increases
More root action
Eventually trees establish
leading to the development
of a climax community on
mature soils
TIME

57. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Garigue species naturally appear in the forest community
But are at low density because of competition for light

58. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Where a gap naturally appears
A Garigue like community develops - less competition for light

59. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Human influence
Forest clearance and
grazing creates permanent
gaps

60. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

61. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

62. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Garigue formation

63. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Garigue formation
Formation:
Maintained by grazing and agriculture
Abiotic in fluencies:
Climatic - Warm and dry

64. Biotic community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

65. Biotic community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Patchwork of -
Grasses
Thistles
Thorny shrubs
Aromatic flowering plants (herbs)
Topic 2.1 link
How might the biotic
plant community of the
Garigue demonstrate
the concept of the
niche?

66. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Topic 2.1: Revisiting theNiche concept
Niche
A species’ share of a habitat and the resources in it.
An organism’s ecological niche depends not only on where it
lives but on what it does.

67. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Falco pereginus
the sum total of an organism's use of the biotic and
abiotic resources in an environment
Topic 2.1: Revisiting the Niche concept - Competition

68. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Food needed
etc.
Space needed
Climate needed
Falco pereginus
the sum total of an organism's use of the biotic and
abiotic resources in an environment
Topic 2.1: Revisiting the Niche concept - Competition

69. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Topic 2.1: Revisiting the Niche concept
Fundamental niche:
the set of resources a
population is theoretically
capable of using under
ideal conditions
the sum total of an organism's use of the biotic and
abiotic resources in an environment

70. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Topic 2.1: Revisiting the Niche concept
Fundamental niche:
the set of resources a
population is theoretically
capable of using under
ideal conditions
Realised niche:
the resources a population
actually uses
the sum total of an organism's use of the biotic and
abiotic resources in an environment

71. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
The realised niche may
be smaller than the
fundamental niche
because of competition
with other species or
other individuals in the
same population
the sum total of an organism's use of the biotic and
abiotic resources in an environment
Topic 2.1: Revisiting the Niche concept - Competition

72. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
The realised niche may
be smaller than the
fundamental niche
because of competition
with other species or
other individuals in the
same population
Species 2Species 1
Resource Overlap
Species 2Species 1
Resource Overlap
the sum total of an organism's use of the biotic and
abiotic resources in an environment
The more competition the smaller the realised niche
Topic 2.1: Revisiting the Niche concept - Competition

73. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
If the competition is too great between species ONE species will
out compete the other
If the competition is too great within a species then the
population could collapse
the sum total of an organism's use of the biotic and
abiotic resources in an environment
Topic 2.1: Revisiting the Niche concept - Competition

74. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Fundamental Niche
of species found in the
Forest community
Fundamental Niche
of species found in the
Garigue community
Fundamental Niche
of species found in the
Grassland community
Topic 2.1: Revisiting the Niche concept - Competition

75. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Topic 2.1: Revisiting the Niche concept - Competition
However there is
competition as Garigue
species are also found in
either the forest or
grassland communities

76. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Topic 2.1: Revisiting the Niche concept - Competition
The realised niche of
species of the Garigue
community when found in
either the forest community
or grassland community
Garigue community species
are out competed for
resources when found in
forests or grasslands
Garigue species are also
found in forest or grassland
community

77. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Topic 2.1: Revisiting the Niche concept - Competition
Where the Garigue exists as
a natural tradition between
forest and grassland zones,
Garigue species face less
competition

78. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Topic 2.1: Revisiting the Niche concept - Competition
When the forest is cleared
for grazing and the Garigue
that forms is maintained
through grazing

79. Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession
Topic 2.1: Revisiting the Niche concept - Competition
1000m
100m
500m
Forest Community
Grassland Community
Garigue Community
X
Realised niche of Garigue
species without and with
grazing pressure (human
influence)
Limiting factor for Garigue
species competing in the
forest community is light
Removal of the tree cover
opens up opportunity for
Garigue species. Grazing
maintains that opportunity

80. Summary of conditions that allow the development and
maintenance of the Garigue community
Topic 2: Ecosystems and
Ecology
Topic 2.4: Biomes, Zonation and Succession

81. Abiotic conditions

82. Abiotic conditions
Dry Mediterranean climate
Warm summers
Mild winters
Low precipitation
South facing -towards the sun
Steep stoney well drained soils
Biotic conditions
Man
Removal of forest vegetation for
pasture and fuel
Grazing by goats - removes
tree seedlings
Patches of thorny shrubs and
plants - defines against grazing
by sheep and cattle
Aromatic plants (herbs) with
chemical defences against
grazing. e.g. Lavender, Thyme,
Wormwood

83. Work cited:
“Mediterranean Vegetation.” A Guide to the Vegetation of Britain and Europe,
by Oleg Polunin and Martin Walters, Oxford University Press, 1985, p. 131.
NB* Unless stated in the presentation all illustrations, figures and images are the property and copyright of N Gardner. sciencebitz.com
Topic 2: Ecosystems and
Ecology
Topic 2.2: Communities and Ecosystems