Embed Size (px)
Citation preview
Structural dynamics and robustness of food webs
Phillip StaniczenkoDepartment of Physics and Saïd Business SchoolOxford University
In collaboration with:
Owen Lewis Department of Zoology Oxford UniversityOwen Lewis Department of Zoology, Oxford UniversityNick Jones Systems Biology, Oxford UniversityFelix Reed-Tsochas Cabdyn Complexity Centre, Oxford
8th June 2010, Saïd Business School, Oxford University
IImage:NASA(2000)
Overview
• Modelling community ecology
• Structural dynamics and robustness of food webs
• Other projects• Other projects
Modelling community ecology
More realistic
Dynamic
erac
tion Kondoh
2003Petchy et al.
2008
Static
ecifi
c in
te
More realistic May1973
Roopnarine et al.2007
NoneInte
rspe
Staniczenko et al.2010
Dunne et al.2002
None Static Dynamic
F d b t tFood web structure
Modelling community ecology
More realistic
Dynamic
erac
tion Kondoh
2003Petchy et al.
2008
Static
ecifi
c in
te
More realistic May1973
Roopnarine et al.2007
NoneInte
rspe
Staniczenko et al.2010
Dunne et al.2002
None Static Dynamic
F d b t tFood web structure
Modelling community ecology
More realistic
Dynamic
erac
tion Kondoh
2003Petchy et al.
2008
Static
ecifi
c in
te
More realistic Roopnarine et al.2007
May1973
NoneInte
rspe
Staniczenko et al.2010
Dunne et al.2002
None Static Dynamic
F d b t tFood web structure
Stability and complexity in model ecosystems
May (1973) Princeton University Press, Princeton NJ
Modelling community ecology
More realistic
Dynamic
erac
tion Kondoh
2003Petchy et al.
2008
Static
ecifi
c in
te
More realistic May1973
Roopnarine et al.2007
NoneInte
rspe
Staniczenko et al.2010
Dunne et al.2002
None Static Dynamic
F d b t tFood web structure
Network structure and biodiversity loss in food webs
Dunne et al. (2002) Ecology Letters 5, 558-567
Modelling community ecology
More realistic
Dynamic
erac
tion Petchy et al.
2008Kondoh
2003
Static
ecifi
c in
te
More realistic May1973
Roopnarine et al.2007
NoneInte
rspe
Staniczenko et al.2010
Dunne et al.2002
None Static Dynamic
F d b t tFood web structure
Foraging adaptation and the relationship betweenfood web complexity and stabilityfood-web complexity and stability
Before After
Kondoh (2003) Science 299, 1388-1391
Modelling community ecology
More realistic
Dynamic
erac
tion Kondoh
2003Petchy et al.
2008
Static
ecifi
c in
te
More realistic May1973
Roopnarine et al.2007
NoneInte
rspe
Staniczenko et al.2010
Dunne et al.2002
None Static Dynamic
F d b t tFood web structure
Trophic network models explain instability of Early Triassicterrestrial communitiesterrestrial communities
Roopnarine et al. (2007) Proc. R. Soc. B 271, 2077-2086
Modelling community ecology
More realistic
Dynamic
erac
tion Kondoh
2003Petchy et al.
2008
Static
ecifi
c in
te
More realistic May1973
Roopnarine et al.2007
NoneInte
rspe
Staniczenko et al.2010
Dunne et al.2002
None Static Dynamic
F d b t tFood web structure
Size, foraging, and food web structure
Petchey et al. (2008) PNAS 105, 4191-4196
Modelling community ecology
More realistic
Dynamic
erac
tion Kondoh
2003Petchy et al.
2008
Static
ecifi
c in
te
More realistic May1973
Roopnarine et al.2007
NoneInte
rspe
Dunne et al.2002
Staniczenko et al.2010
None Static Dynamic
F d b t tFood web structure
Structural dynamics and robustness of food webs
• Introduce a model with realistic, dynamic, food-web structure
• Identify a new category of species that promote adaptive robustness
Implications for biodiversity conservation
Which species removalscause the largest
Which species provideecosystem stability
knock-on effect? in the first place?
Staniczenko et al. (2010) Ecology Letters 13, 891-899
Chesapeake Bay food webss
7
6
of b
iom
as 6
5
Flow
o 5
44
3
2Resource
Trophic Level 1layer
Predator-prey rewiring model
Structural robustness
Chesapeake Bay
Average of1,000
simulations
Method based on J. A. Dunne et al., Ecology Letters 5, 558 (2002)
Structural robustness
Extinction sequence forms
• Random
• Preferentially removing specieswith low degree
• Preferentially removing speciesat high trophic level
Method based on J. A. Dunne et al., Ecology Letters 5, 558 (2002)
Structural robustness
Proportional increase in robustness
RR 0
1 RRRR r
−−
=+
Expected range [ 0,1 ]
01 R
R0
R
Method based on J. A. Dunne et al., Ecology Letters 5, 558 (2002)
Rr
Structural robustness in empirical food webs
Structural robustness in empirical food webs
Sh lf Sh lf +ShelfSt. Marks SeagrassBridge Brook LakeR f, R
0
ShelfSkipwith PondSt. Martin IslandS M k S
stne
ss, R
+
ReefSt. Martin IslandBenguela
obus
tnes
s, St. Marks SeagrassLittle Rock LakeBridge Brook Lake
se in
robu
Coachella ValleyLittle Rock LakeYthan Estuary ‘91ru
ctur
al ro Benguela
Ythan Estuary ‘91Chesapeake Bay na
l inc
reas
Ythan Estuary ‘96Chesapeake BaySkipwith Pond
St Reef
Ythan Estuary ‘96Coachella Valley P
ropo
rtion
Structural robustness in empirical food webs
Sh lf +ShelfSkipwith PondSt. Martin IslandS M k SBi di it ?
stne
ss, R
+
St. Marks SeagrassLittle Rock LakeBridge Brook Lake
Biodiversity?
Link density, Connectance?
se in
robu
BenguelaYthan Estuary ‘91Chesapeake Bay
Top, Intermediate, Bottom species?
Average trophic level?
nal i
ncre
as
ReefYthan Estuary ‘96Coachella Valley P
ropo
rtion
Structural robustness in empirical food webs
Sh lf +ShelfSkipwith PondSt. Martin IslandS M k SBi di it ?
stne
ss, R
+
St. Marks SeagrassLittle Rock LakeBridge Brook Lake
Biodiversity?
Link density, Connectance?
se in
robu
BenguelaYthan Estuary ‘91Chesapeake Bay
Top, Intermediate, Bottom species?
Average trophic level?
nal i
ncre
as
ReefYthan Estuary ‘96Coachella Valley P
ropo
rtion
Overlap species
• Species in the rewiring graph with kout > 0
• Offer biologically-plausible potential predators to other species
• Provide a compensatory mechanism that enables ecosystem adaptationProvide a compensatory mechanism that enables ecosystem adaptation
Overlap species
Chesapeake Bayrewiring graphg g p
Overlap species and the proportional increase in robustness
r = 0.94
Summary
• Introduced a model with realistic, dynamic, food-web structure
• Shown some results for empirical food webs
• Identified a new category of species that promote adaptive robustnessIdentified a new category of species that promote adaptive robustness
Further work
• Theoretical:
• Consider synthetic food webs• Apply to mutualistic and antagonistic ecological networks• Incorporate with population dynamic modelsp p p y
• Empirical:
• Overlap species in the field• Phylogenetic relationships• Implications for ecosystem conservation and management
Which species removalscause the largest
Which species provideecosystem stabilityg
knock-on effect?y y
in the first place?
Projects
• Rapidly detecting disorder in rhythmic biological signals.Staniczenko, Lee & Jones (2009) Phys. Rev. E 79:011915., ( ) y
• Structural dynamics and robustness of food webs.Staniczenko, Lewis, Jones, Reed-Tsochas (2010) Ecology Letters 13, 891.
• Spatial contagion of fluctuations in social systems.Staniczenko, Reed-Tsochas, Plant & Johnson (2010) in preparation.
• Reallocation and switching dynamics in quantitative host-parasitoid food webs.Staniczenko, Lewis & Reed-Tsochas (2010) in preparation.
• Nestedness in quantitative antagonistic and cooperative ecological networks• Nestedness in quantitative antagonistic and cooperative ecological networks.Staniczenko, Lewis & Reed-Tsochas, on going.
• Biodiversity optimisation in multi-functional ecosystems.Bagchi, Garlaschelli & Staniczenko, on going.
![Di raction Line Imaging€¦ · 26], and rainbow particle velocimetry [35].Unlike prior works, our method uses di raction to encode the spatial position of scene light sources. In](https://img.pdfslide.us/doc/110x75/606681c00478de56b87ec1cd/di-raction-line-imaging-26-and-rainbow-particle-velocimetry-35unlike-prior.jpg)
