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THE VALUE OF PASTORALISM IN MEDITERRANEAN THE VALUE OF PASTORALISM IN MEDITERRANEAN PLANT DIVERSITY CONSERVATIONPLANT DIVERSITY CONSERVATION
Begoña Peco VázquezDepartamento de Ecología
Universidad Autónoma de Madrid
Spatial gradients linked to topography & presence of trees
Inter-annual rainfall variations = > availability of water and nutrients
Grassland management activities (ploughing)
The role of Herbivores: disturbance (defoliation, trampling, grubbing, dung), nutrient availability (dung) and seed dispersal
FACTORS RELATED TO SPECIES RICHNESS
FACTORS RELATED TO SPECIES FACTORS RELATED TO SPECIES RICHNESSRICHNESS
SPATIAL STRUCTURESPATIAL STRUCTURESPATIAL STRUCTURE
SHADOW
LEVEL OF LAYER SATURATEDBY GROUNDWATER
FLAT, MOIST ZONES DUE TO GROUNDWATER DISCHARGE THROUGH FRACTURES
ROCK OUTCROPS
VALLEY FLOOR: MOIST DEPRESSIONS & DALES
STREAM
HILL SLOPESHADOW FACE HILL HILL SLOPE
SUNNY FACESOIL WITH WATER BASE
SOIL WITH EARTH BASE
HILLOCK HIDDEN SEEPAGE
FLAT ZONES WITH RELATIVELY DEEP SOILSSLOPES WITH SHALLOW SOILS
Bernáldez & Peco (1991)
Puerto et al., 1990. J.Veg.Sci.
100 200 300 400 500 600 700 800 900
Biomass (g/m2)Biomass (g/mBiomass (g/m22))
Nº
spp
(2
,5m
2)
Nº
spp
(2
,5m
Nº
spp
(2
,5m
22 ))
80
70
60
50
40
30
20
10
Div
ersi
tyD
iver
sity
Div
ersi
ty
DistanceDistanceDistance
EFFECT OF TREESEFFECT OF TREESEFFECT OF TREES
Bernáldez et al, (1969) Bol. Soc. Esp. Hist. Nat., 67
FLO
RIS
TIC
CO
MP
OSI
TIO
NFL
OR
ISTI
C C
OM
PO
SITI
ON
FLO
RIS
TIC
CO
MP
OSI
TIO
N
TIMETIMETIME
GRASSLAND DYNAMICSGRASSLAND DYNAMICSGRASSLAND DYNAMICS
PREDATION DISPERSAL SEEDLINGDEATH
GERMINATION
PATHOGENSPHYSIOLOGICALDEATHS
TRANSIENTTRANSIENT
PERSISTENTPERSISTENT
SEED BANKSEED BANK
VEGETATIONVEGETATIONSEED PRODUCCION
SEEDRAIN
Thompson & Grime (1979) J. Ecol, 67
TYPES OF SEED BANKS IN MEDITERRANEAN GRASSLANDS
TYPES OF SEED BANKS IN TYPES OF SEED BANKS IN MEDITERRANEAN GRASSLANDSMEDITERRANEAN GRASSLANDS
SUMMERTRANSISTORY
SUMMERSUMMERTRANSISTORYTRANSISTORY
WINTER TRANSISTORYWINTER TRANSISTORYWINTER TRANSISTORYSEMI-PERSISTENTSEMISEMI--PERSISTENTPERSISTENT
PERSISTENTPERSISTENTPERSISTENT
SUCCESION AFTER PLOUGHINGSUCCESION AFTER PLOUGHINGSUCCESION AFTER PLOUGHING
Pineda, F. D., et al. (1981) Vegetatio 44, 165-176
I
II
25spp 29spp
32spp
48spp
Years after ploughing1 >40
FLORISTIC COMPOSITION AND SUCCESSION
FLORISTIC COMPOSITION AND FLORISTIC COMPOSITION AND SUCCESSIONSUCCESSION
PIONEER STAGESPIONEER STAGES INTERMEDIATE STAGESINTERMEDIATE STAGES ADVANCED STAGESADVANCED STAGES
CO
MM
UN
ITY
C
OM
MU
NIT
Y
STR
UC
TUR
EST
RU
CTU
RE
INFI
LTR
ATI
ON
INFI
LTR
ATI
ON
VER
SUS
VER
SUS
RU
NR
UN
-- OFF
OFF
MICROTOPOGRAPHY GEOMORPHOLOGY
COMMUNITY STRUCTURE AND SUCCESION
COMMUNITY STRUCTURE AND COMMUNITY STRUCTURE AND SUCCESIONSUCCESION
13
12
10118
6
9
7
D =a0 + a1 SITE + a2 YEAR + a3 SITExYEAR +a4 AUTUMN RAIN + a5 TOTAL RAIN
Axis 1
Axis 2
Peco, B. 1989, Vegetatio, 83: 269-276
COMMUNITY DYNAMICSCOMMUNITY DYNAMICSCOMMUNITY DYNAMICS
ROLE OF LARGE HERBIVORESROLE OF LARGE HERBIVORESROLE OF LARGE HERBIVORES
EUROPEAN RUMINANTS
reindeer Spanish ibex
deer
southern chamois
roedeer
goat
elk
bison
fallow deer
sheep
mouflon
ccw
uro
volume quality volume quality
Feeding pattern
TYPE OF HERVIBORETYPE OF HERVIBORETYPE OF HERVIBORE
Hoffman (1989) Oecología 78
NIT
RÓ
GEN
O T
OTA
L (%
)
0.02
0.06
0.10
0.14
0.18
0.22
0.26
0.30
0.34
H. seco H. húmedo H. arbolado
Nitrogen Organic matter
GRAZED UNGRAZEDGRAZED UNGRAZED
EFFECT OF GRAZING ON SOILS EFFECT OF GRAZING ON SOILS
MA
TER
IA O
RG
ÁN
CIA
OXI
DA
BLE
(%)
0
1
2
3
4
5
6
7
H. seco H. húmedo H. arbolado
Dry Wet TreeDry Wet Tree
000
101010
202020
303030
404040
505050
606060
707070
808080
RabbitRabbitRabbit Fallow deer
Fallow Fallow deerdeer
DeerDeerDeer CowCowCow
SPECIES DISPERSED IN DUNG (312 gr)SPECIES DISPERSED IN DUNG (312 gr)SPECIES DISPERSED IN DUNG (312 gr)
Malo & Suárez (1995), J. Veg. Sci, 6
00500500
100010001500150020002000250025003000300035003500400040004500450050005000
RabbitRabbit Fallow Fallow deerdeer
DeerDeer CowCow
SEEDS DISPERSED IN DUNG (312 gr.)SEEDS DISPERSED IN DUNG (312 gr.)SEEDS DISPERSED IN DUNG (312 gr.)
Malo & Suárez (1995), J. Veg. Sci, 6
Peco & Merino (2004)
4412N =
Seed hardnessintermediatehardsoft
Effe
ct o
nge
rmin
atio
n (t-
c)
40
20
0
-20
-40
-60
-80
-100
DUNG versus GRASSLANDSDUNG DUNG versusversus GRASSLANDSGRASSLANDS
00
22
44
66
88
1010
1212
1414
1616
1st YEAR1st YEAR 2nd YEAR2nd YEAR 3rd YEAR3rd YEAR 4th YEAR4th YEAR
J= 0.53J= 0.53J= 0.68J= 0.68
J= 0.75J= 0.75
J= 0.685J= 0.685
PASTUREDUNG
SPEC
IES
PER
SA
MP
LESP
ECIE
S P
ER S
AM
PLE
GRAZING & DIVERSITYGRAZING & DIVERSITYGRAZING & DIVERSITY
MOISTUREMOISTURE
Milchunas et al. 1988, Am. Nat. 132 (1)
EVO
LUTI
ON
AR
Y H
ISTO
RY
OF
GR
AZI
NG
EVO
LUTI
ON
AR
Y H
ISTO
RY
OF
GR
AZI
NG
Grazing intensity
Diver
sity
Semiarid Sub-humid
Shor
tLo
ng
a) Theoretical ratioa) Theoretical ratio b) Ratio foundb) Ratio found
Ric
hn
ess
0 100 200 300 400 500
Area (m2)Area
No grazing
grazing
No grazing
grazing
Div
ersi
ty
Chaneton & Facelli, 1991Vegetatio 93
SCALE DEPENDENT EFFECTSCALE DEPENDENT EFFECTSCALE DEPENDENT EFFECT
0
510
1520
2530
35
500 700 900 1100 1300 1500 1700 1900Altitud (m)
RIC
HN
ESS
(0.0
4 m
2) a)
0
5
10
1520
25
3035
500 700 900 1100 1300 1500 1700 1900
RIC
HN
ESS
(04
m2 )
Altitud (m)
b)
GRAZED UNGRAZED
Peco et al., 1998. J.Veg.Sci .9
SPECIES RICHNESS AND ABANDONMENTSPECIES RICHNESS AND ABANDONMENTSPECIES RICHNESS AND ABANDONMENT
Upper slope zones Lower slope zones
0
6
12
1986 87 88 89 900
6
12
1986 87 88 89 90
0
8
16
1986 87 88 89 90
0
12
24
1986 87 88 89 90
0
12
24
1986 87 88 89 90
0
12
24
1986 87 88 89 90
I
Upper slope zones Lower slope zonesAltitude
1719m.
1449m.
1215m.
891m.
642m.
I
I
II
III
I II III
II
II
II I
I
II
I
I
II
IIII
II
I
I
YearYear
I
I II IIIIII
Grazed
Ungrazed
II
0
12
24
1986 87 88 89 90
I
0
6
12
1986 87 88 89 90
0
8
16
1986 87 88 89 90
0
12
24
1986 87 88 89 90
0
12
24
1986 87 88 89 90
II I
II
II
II
I
II
I
I
II
I
I
II
II
II I
I I
I
II
I I
I I
I
I
I
II
II
I II
II
I
I
Spec
ies
richn
ess
(0.0
4m2 )
LONG-TERM ABANDONMENTLONGLONG--TERM ABANDONMENTTERM ABANDONMENT
ABANDONEDABANDONED GRAZEDGRAZED
LONG-TERM GRAZING ABANDONMENT
LONGLONG--TERM GRAZING TERM GRAZING ABANDONMENTABANDONMENT
Peco & Sánchez 2003
0
5
10
15
20
25
Wet Dry Under tree
GRAZED
UNGRAZED
Number of species (0.04m2)Number of species (0.04m2)
LONG-TERM GRAZING ABANDONMENT
LONGLONG--TERM GRAZING TERM GRAZING ABANDONMENTABANDONMENT
Peco & Sánchez 2003
STRESS=0.15
DHDHDHDH
DH
DSDS
DS
DS
DS
MS
MS
MS
MSMS
MH
MH
MH
MH
MH
-1,4
-0,8
-0,2
0,4
1,0
1,6
-1,8 -1,2 -0,6 0,0 0,6 1,2 1,8
GRAZED
UNGRAZED
Jaccard Similarity51%
Exclusive species:
Grazed: 43
Ungrazed: 66
CONCLUSIONSCONCLUSIONSCONCLUSIONS
In Mediterranean dehesa grasslands, species richness is linked to:
Spatial gradients and periods of water availability
Low-frequency disturbances linked to traditional farm management
Extensive grazing As a generator of low-intensity
disturbancesAs a seed dispersal agent
CONCLUSIONSCONCLUSIONSCONCLUSIONS
Grazing abandonment and species richness is time dependent
• Short term abandonment produces a decrease in species richness particularly in wet microsites. Nevertheless the effect is not always consistent
• Long-term abandonment causes the loss of almost 50% of grassland species in dehesas, but richness at the community scale does not decline thanks to the input of new scrubland-specific species.
CONCLUSIONSCONCLUSIONSCONCLUSIONS
Livestock management plans should therefore include:
Creation & maintenance of gradients & mosaicsDiversification of grazing intensity in space & time.Use of different species of grazersThe presence of abandoned areas should also be contemplated for maximizing plant diversity at the landscape level.