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 Ecosystems??? Ecosystem services

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

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 (P) Livestock: forage for cattle, sheep, etc Goods and benefits Food (meat, milk), fibre (wool), possibly enhanced quality of meat and milk (P) Standing vegetation: biomass crops (P) Crops: pollination and pest control spillover (C) Socially valued landscapes: valued species and habitats, agricultural heritage, archaeological heritage, grazing for rare livestock breeds, ecological knowledge, training areas (R) Climate regulation: sequestration and storage of carbon and other greenhouse gases (P, R) Water quantity: storage of water and recharging of aquifers (P, R) Purification: reduced pollution and storage of pollutants (P,R) Wild species diversity: plant genetic diversity, seed for restoration projects Possibly fuel Food (crops) Physical and psychological health, social cohesion, recreation and tourism, research base, military training Avoidance of climate stress Potable water, water for food production, flood protection Clean air, clean water, clean soils, 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 (P) Livestock: forage for cattle, sheep, etc (P) Harvestable vegetation biomass Role of local (plant) species richness Compared with other UK ecosystems Better than Worse than Positive Moorland, heaths, etc Improved grassland, arable 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, seed for restoration Positive Improved grassland, arable -

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

Reference Restoration Degraded state 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. Management of services and biodiversity: a meta-analysis 89 restorations across the world tropical/temperate, aquatic/terrestrial Bauxite mine Eroded coral Logged mangrove Arable agriculture Soil and tree replacement Artificial reef Re-planted trees Wildflower sowing Native forest Coral reef Mangrove swamp Hay meadow

Range of measures used Biodiversity e.g. Provisioning e.g. Regulating e.g. Supporting e.g. Species richness Commercial crab production Thermal buffer capacity Diversity indices Fish biomass Runoff coefficient Species composition Performance of a target species Microbial biomass Density of commercial trees Water quality Soil compaction Total C Salinity Eel abundance Total Pb Soil respiration 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)