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A shrubland, an open savanna or a woodland:

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Title: A shrubland, an open savanna or a woodland:


1
A shrubland, an open savanna or a woodland The
shaping forces of fire, grazing and clear-cutting
around the globe and in Burn Unit 113.
Orna Reisman-Berman Department of Geography and
Environment Bar-Ilan University , Israel.
2
Sapling Release form Fire Trap in a Low Frequency
Fire Regime
or
Factors controlling post-fire sapling recovery
sapling developmental stage, fire patchiness and
re-sprouting dynamics
Dave Peterson Cindy Buschena Jared TrostBrian
Pelc Susan Barrott TD SP EH JL KAS Orna
Reisman-Berman
A long-term study in BU 113 and 111
Peter Reich
3
An open Mediterranean woodland Garrigue
4
A closed Mediterranean Woodland Maquis
Choresh (Hebrew) (Chaparral California Espinal
Chille)
5
Elderly Trees Sacred Trees
Quercus ithaburensis Mount Tabor oak
Quercus calliprinos Kermes oak
6
Mediterranean woodland species - Sacred Trees
near sacred sites
Quercus ithaburensis
Olive trunk
Quercus calliprinos
siliqua Ceratonia
Pistacia palaestina
7
Mt. Meron 1945
Galilee, Northern Israel 1000 mm rainfall
Carmel Kadmon. 1999. Plant Ecology. 145239
8
Mt. Meron 1964
Carmel Kadmon. 1999. Plant Ecology. 145239
9
Mt. Meron 1992
Carmel Kadmon. 1999. Plant Ecology. 145239
10
Sarcopoterium spinosum shrubland The transition
area between the Mediterranean and the semi-arid
zones, 250-350 mm rainfall
1960
1974
1999
Reisman-Berman, Kadmon Shachak. 2006.
Ecography, 29418
11
Shmida 1985 Species diversity with relation to
woodland openness
Species diversity
Annuals abundance
Open (gap)
Woodland openness
close
12
Traditional Practices Everyday activities
(forces) in a Mediterranean ecosystem
1. Grazing
13
  • Clear-cutting
  • Fuel for home use and lime kilns

14
3. Occasional small scale fires In Greece
traditional practice to increase herbaceous
species cover (increasing ecosystem NPP).
15
Some 60 years ago modernization and exclusion
of traditional practices
16
Closed woodland
Open woody vegetation formation
Galilee
Closed woodland
Open Savanna
Cedar Creek
17
Consumer controlled ecosystems
CC type ecosystem high water availability
Fire
Open woodland
Closed woodland
Grazing, Clear-cutting, (Fire)
Mediterranean type ecosystem - low water
availability
sensu Bond Keeley. 2005. TREE 20387
18
Regeneration traits
Re-sprouting following grazing Mediterranean zone
Re-sprouting following fire BU113
19
  • Research questions related to the Mediterranean
  • Natural history
  • What was the ancient landscape?
  • Bio-geography
  • What is the typical vegetation formation?
  • Ecology
  • What controls the transition from one state to
    the other state (open to close woodland and vise
    versa)?
  • Ecosystem function of open and closed states?
  • Stability of each state?
  • Species composition of each state? Biodiversity?
  • Conservation and management
  • How to control the transitions?
  • How to maintain each of the different states?

20
LTER stations along the precipitation gradient in
Israel
21
Sarcopoterium spinosum Shrubland Lehavim LTER
250 mm rainfall
22
Ramat Hanadiv LTER 650 mm rainfall
52
54
51
53
41
32
42
31
34
43
33
22
44
21
24
23
12
11
14
13
N
23
Consumer pressure
Closed and high woody formation
Open and low woody formation
Null consumer pressure
High pressure
Fire trap recurrent sapling mortality and
resprouting
Fire regime
Closed woodland
Open woodland
To form tall and open woody formation need
periodical releases of sapling from fire trap
24
Sapling thicket
Open woodland
Closed woodland
Fire regime
Release of saplings from fire trap
Low frequency decadal fire sapling thicket
High frequency open Savanna
25
  • Is there variability among saplings in response
    to fire?

2. What could cause the variability among sapling
in surviving fires?
26
2. What could cause variability among sapling in
surviving fires?
  • A. Sapling height - probability of escaping from
    fire increases with sapling height
  • Indications from Dave Peterson survey 1995
  • Was demonstrated in South African Savanna
    (Trollope, W.S.W. 1984)
  • B. Sprout dynamics next generation saplings
  • Initial observations demonstrate that number and
    length of sprouts increase with parent height
    (Dave Peterson).

C. Fire patchiness saplings experience
different fire severities
27
Fire patchiness
Burn Unit scale large patches of high severity
Sapling neighborhood scale
28
Grading fire severity
29
Understanding fire heterogeneity Spatial
patterns and scales of fire-severity
distribution. Random or aggregated?
  • Methodology
  • Mapping sapling points and large patches of high
    severity-fire (including the use of GPS).
  • Data compilation and analysis in GIS software.

30
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