Download Quantifying the evidence for biodiversity effects on ecosystem

What is the ecological evidence for
a link between biodiversity and
ecosystem services?
James Bullock & Phil Martin
Centre for Ecology & Hydrology
Evidence vs Belief
Millennium
Ecosystem
Assessment
Biodiversity
↓
Ecosystem Services
What is Biodiversity?
3 levels:
within species (genetic diversity)
among species (species diversity)
among ecosystems
Convention on Biological Diversity
What are Ecosystem Services?
Biophysical
structure or
process
e.g. woodland
or NPP
Haines-Young R, Potschin M (2009) The links between biodiversity, ecosystem services and
human well-being. In: Raffaelli D, Frid C (eds.): Ecosystem Ecology: a new synthesis.
Questions
Genetic diversity
?
Species diversity
?
Ecosystem services
Ecosystems
?
Questions
Genetic diversity
?
Species diversity
?
Ecosystem services
Ecosystems
?
Species biodiversity
Within ecosystem
Species richness
Diversity indices
Species composition
‘Biodiversity – Ecosystem Function Theory’
More species:
– greater range of functional types
– more likely to include a species which has a
large effect on a function (e.g. a highly
productive plant)
Biodiversity (species
richness) – Ecosystem
functions & services
Meta-analysis of experiments
producers
consumers
mycorrhizae
decomposers
multitrophic
Balvanera, P., et al. (2006) Quantifying the
evidence for biodiversity effects on ecosystem
functioning and services. Ecology Letters 9,
1146-1156
Asymptotic relationship – plateau at moderate/high richness
Meta-analysis of experiments
Cardinale, B.J., et al. (2006) Effects of biodiversity
on the functioning of trophic groups and
ecosystems. Nature 443, 989-992
Species richness – Multiple ecosystem functions
Biodepth Experiments
Hector, A., and
Bagchi, R. (2007)
Biodiversity and
ecosystem
multifunctionality.
Nature 448, 188-190
Issues: species richness → ecosystem services
 How do experiments manipulating richness
relate to real world environmental change?*
 Asymptotic relationship suggests
redundancy & little role for high diversity
 Range of functions/services considered is
limited (productivity)
* Srivastava, D.S., and Vellend, M. (2005) Biodiversity-ecosystem function research: Is it relevant to conservation? Annual Review of
Ecology Evolution and Systematics 36, 267-294; Raffaelli, D. (2006) Biodiversity and ecosystem functioning: issues of scale and
trophic complexity. Marine Ecology Progress Series 311, 285-294
Species richness → cultural services
Lindemann-Matthies, P., et al. (2010) The influence of
plant diversity on people's perception and aesthetic
appreciation of grassland vegetation. Biological
Conservation 143, 195-202
Ecosystem biodiversity → ecosystem services?
Landscape variation in ecosystems (biodiversity) OR
Some ecosystems are better than others for services (not biodiv) ?
Perrings, C., et al. (2010) Ecosystem
Services for 2020. Science 330, 323-324
Ecosystem biodiversity → ecosystem services?
Landscape variation in ecosystems (biodiversity) OR
Some ecosystems are better than others for services (not biodiv) ?
Perrings, C., et al. (2010) Ecosystem
Services for 2020. Science 330, 323-324
Biodiversity is only part of the story
Service provision from an
ecosystem is a product of:
 geology & soil type
 atmospheric inputs
 topography
 hydrology
 human management
 vegetation structure
 other trophic levels
 species identity &
richness
 etc, etc
From USGS website
An example – Semi-natural grasslands in the UK NEA
Semi-natural grasslands in the UK (similar in rest of Europe)
 ~90% lost (by area) since 1940s:- 1.7M ha (1% area)
 → improved grassland, arable, building, forestry, …
 ~250 species of conservation concern (UKBAP)
 Current problems – poor management, eutrophication
Bullock et al. (2011) UK National Ecosystem Assessment: Semi-natural Grasslands
Ecosystem services possibly provided by UK semi-natural grasslands
(evidence quality varies)
Table 3.1. The final services and goods provided by SNG
Final ecosystem service
Goods and benefits
(P) Livestock: forage for cattle, sheep, etc
Food (meat, milk), fibre (wool), possibly
enhanced quality of meat and milk
(P) Standing vegetation: biomass crops
Possibly fuel
(P) Crops: pollination and pest control spillover
Food (crops)
(C) Socially valued landscapes: valued species and
habitats, agricultural heritage, archaeological
heritage, grazing for rare livestock breeds,
ecological knowledge, training areas
Physical and psychological health, social
cohesion, recreation and tourism, research
base, military training
(R) Climate regulation: sequestration and storage of
carbon and other greenhouse gases
Avoidance of climate stress
(P, R) Water quantity: storage of water and
recharging of aquifers
Potable water, water for food production, flood
protection
(P, R) Purification: reduced pollution and storage of
pollutants
Clean air, clean water, clean soils,
(P,R) Wild species diversity: plant genetic diversity,
seed for restoration projects
Genetic resources, bioprospecting, recreation
and tourism, ecological knowledge
Bullock et al. (2011) UK National Ecosystem Assessment: Semi-natural Grasslands
What is the role of biodiversity in service provision by UK SNG?
Ecosystem service
Compared with other UK ecosystems
Better than
Worse than
Role of local (plant)
species richness
Positive
Moorland, heaths, etc
Improved grassland,
arable
(P) Harvestable vegetation
biomass
Positive?
Moorland, heaths, etc
Improved grassland,
arable, woodland
(P) Crops: pollination and
pest control
Positive?
Improved grassland,
arable, woodland
-
(C) Socially valued
landscapes
Positive?
Improved grassland,
arable
?? Woodland,
moorland, wetland,
coast ??
(R) Sequestration and
storage of GHG
Positive
Improved grassland,
arable
Woodland, moorland,
wetlands
(P, R) Water quantity: floods
& aquifers
None
Improved grassland,
arable
Woodland, moorland,
wetlands
(P, R) Water quality
Positive
Improved grassland,
arable
Woodland, moorland,
wetlands
(P,R) Plant genetic diversity, Positive
seed for restoration
Improved grassland,
arable
-
(P) Livestock: forage for
cattle, sheep, etc
Mapping – UK services & biodiversity
are not correlated
Strassburg, et al. 2010. Conserv. Lett.
Recreation
Anderson, B.J., et al. (2009) Spatial covariance between biodiversity and other
ecosystem service priorities. Journal of Applied Ecology 46, 888-896
Management of services and biodiversity: a meta-analysis
Degraded state
89 restorations across the world – tropical/temperate, aquatic/terrestrial
Bauxite mine
Logged mangrove
Artificial reef
Re-planted trees
Wildflower sowing
Mangrove swamp
Hay meadow
Arable agriculture
Restoration
Soil and tree replacement
Eroded coral
Coral reef
Reference
Native forest
Rey Benayas, J.M., Newton, A.C., Diaz, A. & Bullock, J.M. (2009) Enhancement of biodiversity and ecosystem services by ecological
restoration: a meta-analysis. Science, 325, 1121-1124.
Range of measures used
Biodiversity
e.g.
Provisioning
e.g.
Regulating
e.g.
Supporting
e.g.
Species richness
Commercial
crab production
Thermal buffer
capacity
Soil
compaction
Diversity indices
Fish biomass
Runoff
coefficient
Total C
Species
composition
Density of
commercial
trees
Water quality
Salinity
Performance of
a target species
Eel abundance
Total Pb
Soil respiration
Microbial
biomass
Preference by
livestock
Sedimentation
Denitrification
potential
Rey Benayas et al. (2009) Science
Changes in services & biodiversity are correlated
Causation?
OR Common drivers?
Rey Benayas et al. (2009) Science
Relationship is weaker comparing restored with reference
More complex ecological processes + asymptotic relationship?
Rey Benayas et al. (2009) Science
Issues & conclusions
 Local species richness→(certain) services, but need
more real world studies
 The species richness→services argument does not
justify conservation of valued ecosystems
 Variation among ecosystems in service provision has
many drivers; biodiversity may have a minor role
 An ecosystem of conservation value may provide
valued services, but others may provide better services
 But – ecosystem management might be designed to
enhance both biodiversity and services
Landscape-scale interactions among ecosystems in service delivery
From UK NEA draft (Ed Maltby)