Biodiversity and Functioning of Terrestrial Ecosystems

Lucie Zinger UMR 8197 IBENS – Institut de Biologie de l'École Normale Supérieure, 46 rue d’Ulm, 75005, Paris. [email protected]

Some recent news clippings

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The Living Planet Index - 2018 update

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Global trend of populations decline of ca. 60% between 1970 and 2014

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Global trend of populations decline of ca. 60% in the last 40 years WWF. Living Planet Report (2018). Aiming higher. WWF International, Gland, Switzerland

Global change threats - 2018 updates

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Why it matters: ecosystem sustainability

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Joseph Priestley (1733-1804)

The Priestley Jar Experiment

Unsustainable system

Sustainable system

Adapted from Naeem. S.; Gorham, E. (1991). Biogeochemistry: its origins and development. Biogeochemistry, 13(3), 199-239.

Why it matters: ecosystem sustainability Joseph Priestley @priestleyJ ‧ Jun 1772 it is highly probable, that the injury which is continually done to the atmosphere by the respiration of such a number of animals, and the putrefaction of such masses of both vegetable and animal matter, is, in part at least, repaired by the vegetable creation. […] […] the putrid effluvium is in some measure extracted from the air, by means of the leaves of plants that render the remainder more fit for respiration Benjamin Franklin @BenFranklin ‧ Jun 1772 Replying to @priestleyJ That the vegetable creation should restore the air which is spoiled by the animal part of it, looks like a rational system, and seems to be of a piece with the rest. […] I hope this will give some check to the rage of destroying trees that grow near houses, which has accompanied our late improvements in gardening…

Donald J. Trump

@realDonaldTrump ‧ Mar 2017

[…] We’re going to have clean water. We’re going to have clean air, but so many [environmental regulations] are unnecessary. So many are job-killing. 13K

105K

68K

Adapted from Naeem. S.; Gorham, E. (1991). Biogeochemistry: its origins and development. Biogeochemistry, 13(3), 199-239.

Why it matters: ecosystem sustainability

Biodiversity perspective

Ecosystem perspective

Adapted from Naeem. S.; Gorham, E. (1991). Biogeochemistry: its origins and development. Biogeochemistry, 13(3), 199-239.

Why it matters: ecosystem sustainability Ecosystem perspective Biodiversity perspective

Gravel D., Gounand I. et Mouquet N. (2010). Le role de la diversite dans le fonctionnement des Ecosystemes. Ciencia Ambiente 39.

The anthropocentric perspective of sustainability Linkages among biodiversity, ecosystem services, and human well-being

Millennium Ecosystem Assessment (2005). Ecosystems and Human Well-being: Biodiversity Synthesis. World Resources Institute, Washington, DC.

Need to describe, understand, and predict

high

low

Vascular plant diversity

low

high

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C pools in soils

low

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Biodiversity-Ecosystem Functioning Research (BEF)

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How is biodiversity per se of a given ecosystem related to its function, its stability and sustainability?

Midgley, G. F. (2012). Biodiversity and ecosystem function. Science, 335(6065), 174-175.

The wedding of two disciplines Ecosystem Ecology • Functioning • Fluxes of energy and materials • Physical and geochemical constraints ➡ Macroscopic perspective ✓ Inductive generalisation ➡ Regularity, predictability - No theory & hypothetico-deductive approaches

Population/Community Ecology • Abundance and diversity • Structure and dynamics • Abiotic and biological constraints ➡ Microscopic perspective ✓ solid theoretical framework & hypotheticodeductive ➡ Variability

Naeem, Shahid, J. Emmett Duffy, and Erika Zavaleta (2012): The functions of biological diversity in an age of extinction. Science 336.6087 1401-1406

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A tumultuous story ~350 BC Aristotelian perspective:

all entities share commonalities and traits

~1500 “The Scientific Revolution”: new technologies & rationalisation. 1859 Darwin’s “Principle of Divergence”: a BEF hypothesis premise “A greater absolute amount of life can be supported…when life is developed under many and widely different forms,…the fairest measure of the amount of life being probably the amount of chemical composition and decomposition within a given period” (“Big Species Book”) Hortus Gramineus Woburnensis

~1900

Fragmentation of sciences: “Natural sciences” ➡ distinct disciplines. Naeem (2002). Ecosystem consequences of biodiversity loss: the evolution of a paradigm. Ecology, 83(6):1537-1552

A tumultuous story

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1980s Increasing signs of biodiversity decline 1992

➡ Sustainable development Bayreuth conference: emergence of the BEF hypothesis ➡ Experiment testing BEF hypothesis ➡ BEF debate

2000 UN call for the Millenium Ecosystem Assessment 2001

Paris workshop “Biodiversity and Ecosystem Functioning: Synthesis and Perspectives”

present Naeem (2002). Ecosystem consequences of biodiversity loss: the evolution of a paradigm. Ecology, 83(6):1537-1552

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BEF main concepts • Biodiversity: the number and composition of the genotypes, species, functional types and landscape units in a given system. • Function: any activity, process or property of an ecosystem. • Stocks of energy and materials (e.g. biomass, total carbon) • Fluxes of energy or material processing (e.g. productivity, decomposition) • Stability: dynamics of fluxes rates or stocks over time. • Resistance: ability to persist in the same state in the face of a perturbation • Resilience: ability to return to its former state following
 a perturbation

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Ecosystem process

BEF main early hypotheses

? Natural level Biodiversity

Loreau et al. (2002). Biodiversity and ecosystem functioning: Synthesis and Perspectives,Oxford University Press.

Niche complementarity hypothesis • Link to the niche theory: principle of competitive exclusion ➡ Species are functionally singular

Ecosystem process

➡ Increased ecosystem function through complementarity of e.g. resource use

Biodiversity Loreau et al. (2002). Biodiversity and ecosystem functioning: Synthesis and Perspectives,Oxford University Press.

Redundancy hypothesis

Ecosystem process

• Link to the neutral theory of biodiversity ➡ Species are functionally redundant

Biodiversity

➡ Insurance hypothesis: increased ecosystem stability through compensation of species loss • Depends on the type of environmental fluctuations. Loreau et al. (2002). Biodiversity and ecosystem functioning: Synthesis and Perspectives,Oxford University Press.

Idiosyncrasy hypothesis

Ecosystem process

• Species contribution to functioning depends on environmental conditions. ➡ Species impact is context-dependent

Biodiversity

➡ ≠ from the “null hypothesis”: species role too complex to be predictable. Loreau et al. (2002). Biodiversity and ecosystem functioning: Synthesis and Perspectives,Oxford University Press.

Cedar Creek Biodiversity Experiment, Minnesota, USA

vel of diversity) assland species

168 plots 9x9m 1 to 16 plant species

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BIODEPTH experiment, Europe

480 plots in 8 countries No. of species of 1, 2, 4, 8, 16 of local perennial grassland species

Biodiversity - Productivity Cedar Creek

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BIODEPTH

➡ Generality of effects ➡ Niche related mechanisms (complementarity, facilitation, dilution) Review in Tilman et al. (2014) Biodiversity and Ecosystem Functioning. Annu. Rev. Ecol. Evol. Syst. 45:471–93

The debate

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• The selection or sampling effect (Huston 1997): • Mathematical fact: higher probability of including a species more productive, and/or that facilitates other species • Biological hypothesis: mixed culture behave like monocultures of the most productive species.

Tilman, D., Lehman, C. L., & Thomson, K. T. (1997). Plant diversity and ecosystem productivity: theoretical considerations. PNAS, 94(5), 1857-1861.

The debate

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• Predictions from a generalised niche complementary model

A) the 'snowballs on the barn' model — of niche differentiation and coexistence: • square: soil pH - T°C total niche space • circles: 2D-niche of each species ➡ species “cover” the niche space, information used as a proxy for community biomass. B) Results of simulations and of an analytical solution (solid curve) to the effects of diversity on community productivity for the snowballs on the barn model Tilman, D., Lehman, C. L., & Thomson, K. T. (1997). Plant diversity and ecosystem productivity: theoretical considerations. PNAS, 94(5), 1857-1861.

The debate

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• Predictions from a generalised niche complementary model

A) the 'snowballs on the barn' model — of niche differentiation and coexistence: • square: soil pH - T°C total niche Competition for 1 resource space • circles: 2D-niche of each species ➡ species “cover” the niche space, information used as a proxy for community biomass. B) Results of simulations and of an analytical solution (solid curve) to the effects of diversity on community productivity for the snowballs on the barn model Tilman, D., Lehman, C. L., & Thomson, K. T. (1997). Plant diversity and ecosystem productivity: theoretical considerations. PNAS, 94(5), 1857-1861.

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Complementarity vs. sampling effects ➡ Net effect = Selection effect + Complementarity effect (Loreau & Hector 2001)

Net effect = Increase in yield above that expected from monocultures Selection effect: Due to dominance by most productive species Complementarity effect: Due to improved average performance Selection effect small scale

Niche complementary effect large scale

Cardinale et al. (2007) Impacts of plant diversity on biomass production increase through time because of species complementarity. PNAS 104(46):18123–18128

Biodiversity vs. Abiotic effects

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• Contradiction with empirical studies Productivity

• BEF experiments: • Low environmental variability Species richness Species richness

• Empirical studies: • Steep environmental gradients

Productivity/Fertility Adapted from Loreau, M., et al. (2001). Biodiversity and ecosystem functioning: current knowledge and future challenges. Science, 294(5543), 804-808.

Biodiversity vs. Abiotic effects

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• A matter of spatial scales Regional scale Productivity

Favorable soil and climate ➡ Higher interspecific competition Local scale Environmental heterogeneity ➡ Niche complementarity

Species richness

Unfavourable soil and climate ➡ Strong environmental filtering

Adapted from Loreau, M., et al. (2001). Biodiversity and ecosystem functioning: current knowledge and future challenges. Science, 294(5543), 804-808. Gravel D., Gounand I. et Mouquet N. (2010). Le role de la diversite dans le fonctionnement des Ecosystemes. Ciencia Ambiente 39.

BEF relationship: a pervasive form

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P: Productivity (m3 ha-1 yr-1)

• Global study with > 700,000 forest plots worldwide

Redundancy

Complementarity S: Tree species richness (%) Liang, J., et al. (2016). Positive biodiversity-productivity relationship predominant in global forests. Science, 354(6309), aaf8957.

The species identity effect

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• Context dependency: effect of functional composition and diversity rather than species richness per se E = early-season annuals

P = perennial bunchgrasses

N = nitrogen fixers L = late-season annuals

Review in Tilman et al. (2014) Biodiversity and Ecosystem Functioning. Annu. Rev. Ecol. Evol. Syst. 45:471–93

The limits of taxonomic diversity

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• Species richness is not always a good surrogate of the number of functional groups present Aggregated occupation of niche space (common)

Random or uniform occupation of niche space (uncommon)

Intra-specific functional variability

Dıa ́ z, S., & Cabido, M. (2001). Vive la difference: plant functional diversity matters to ecosystem processes. Trends in ecology & evolution, 16(11), 646-655.

The limits of taxonomic diversity

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Functional diversity

Functional diversity

Functional diversity

• The relationship between functional and species diversity should influence the BEF relationship

Cadotte, M. W., et al. (2011). Beyond species: functional diversity and the maintenance of ecological processes and services. Journal of Applied Ecology, 48(5), 1079-1087.

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Functional BEF? BIODEPTH

• Functional diversity > species richness effects on plant productivity

Cedar Creek

• Soil nutrient accumulation rates is mainly due to functional diversity Monocultures

C3+F C3+F+ C4+L

All

Review in Tilman et al. (2014) Biodiversity and Ecosystem Functioning. Annu. Rev. Ecol. Evol. Syst. 45:471–93

A functional approach to biodiversity

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• Functional ecology is species blind Traits

Functions

Seed mass

Fecundity Dispersal Establishment

Canopy height

Light interception Competitive ability

Specific leaf area Leaf dry matter content Leaf N concentration

Resorption of nutrients Litter decomposability

Density, diameter Specific root length

Absorption (e.g. nutrients) Carbon fluxes (e.g. exsudation) Lavorel, S., & Garnier, E. (2002). Predicting changes in community composition and ecosystem functioning from plant traits: revisiting the Holy Grail. Functional ecology, 16(5), 545-556.

A functional approach to biodiversity

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• Cuts across levels of organisation

Violle, C., et al. (2007). Let the concept of trait be functional!. Oikos, 116(5), 882-892.

A functional approach to biodiversity

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• Cuts across levels of organisation • An example with the specific leaf area (SLA) Net photosynthetic rate (nmol CO2 g-1 s-1)

Relative growth rate (g g-1 d-1) Specific above-ground net primary productivity (g kg-1 d-1)

SLA (m2 kg-1)

Individual SLA (m2 kg-1)

Population SLA (m2 kg-1)

Community Violle, C., et al. (2007). Let the concept of trait be functional!. Oikos, 116(5), 882-892.

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From functions to functional diversity? • Various measures of functional diversity… FAD Sum of distances Functional groups Trait Trait … 1 2 Sp A Sp B

Trait k

A

Traits values

Sp C Sp D

B

D

FGR No. groups

FDvar Trait variance CWM Trait weighted by species abundances

C

FD Total branch length

Adapted from Petchey, O. L., & Gaston, K. J. (2006). Functional diversity: back to basics and looking forward. Ecology letters, 9(6), 741-758.

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From functions to functional diversity? • … with still some uncertainties FAD Sum of distances Trait Trait … 1 2 Sp A Sp B

Trait k

What hypothesis?

Traits values

FDvar Trait variance

Functional groups

A

Sp C Sp D

What metric?

What trait?

CWM Trait weighted by species abundances

What clustering method?

C B

D

FGR No. groups

FD Total branch length

Adapted from Petchey, O. L., & Gaston, K. J. (2006). Functional diversity: back to basics and looking forward. Ecology letters, 9(6), 741-758.

Niche complementarity vs. biomass ratio hypotheses

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• Ecosystem properties are driven by complementary species or by the characteristics of dominant species? Species abundance ➡Niche complementarity

➡Biomass ratio Species rank

Garnier, et al. (2004). Plant functional markers capture ecosystem properties during secondary succession. Ecology, 85(9), 2630-2637.

Functional approach to BEF in natura

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• An example in semi-arid ecosystems Biomass ratio effects Total ecosystem C (Mg ha-1)

Total ecosystem C (Mg ha-1)

Complementarity effects

FDvar of wood-specific gravity

Community weighted mean of height

➡ Dominance of biomass ratio effects

Conti, G., & Díaz, S. (2013). Plant functional diversity and carbon storage–an empirical test in semi-arid forest ecosystems. Journal of Ecology, 101(1), 18-28

Importance of rare species? Tropical forest

Functional vulnerability

Alpine tundra

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Regional occupancy

• Rare species (locally and regionally) sustain unique fonctions ➡ Increase the breadth of functions provided by ecosystems, but have greater extinction risks Mouillot, D., et al. (2013). Rare species support vulnerable functions in high-diversity ecosystems. PLoS Biol, 11(5), e1001569.

A phylogenetic alternative

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• Rely on the idea that functional characteristics are inherited from ancestors and thus conserved. ➡ more synthetic view of ecological differences among species that drive patterns of resource use?

Garnier, E., & Navas, M. L. (2012). A trait-based approach to comparative functional plant ecology: concepts, methods and applications for agroecology. A review. Agronomy for Sustainable Development, 32(2), 365-399.

A phylogenetic alternative

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Cadotte, M. W., et al. (2008). Evolutionary history and the effect of biodiversity on plant productivity. PNAS, 105(44), 17012-17017.

A phylogenetic alternative • Phylogenetic diversity is not always a good proxy of functional diversity

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A first synthesis on local scale BEF

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Experimental sampling or environmental filtering

Adapted from Loreau, M., et al. (2001). Biodiversity and ecosystem functioning: current knowledge and future challenges. Science, 294(5543), 804-808.

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What dynamic?

Environmental Experimental sampling or environmental filtering change?

Species loss?

Ecosystem processes Adapted from Loreau, M., et al. (2001). Biodiversity and ecosystem functioning: current knowledge and future challenges. Science, 294(5543), 804-808.

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Forms of stability Ecosystem function or community attributes

• Resistance describes the ability of a community/ ecosystem attribute to avoid displacement in the first place

Resistance

Alternative stable state Resilience

• Resilience describes the speed with which a community/ecosystem attribute returns to its former state after perturbation Shade, A.,et al. (2012). Fundamentals of microbial community resistance and resilience. Frontiers in microbiology, 3, 417.

Forms of stability

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Ecosystem function or community attributes

• Resistance describes the ability of a community/ ecosystem attribute to avoid displacement in the first place

• Resilience describes the speed with which a community/ecosystem attribute returns to its former state after perturbation

Alternative stable state

Alternative stable state

Shade, A.,et al. (2012). Fundamentals of microbial community resistance and resilience. Frontiers in microbiology, 3, 417.

Biodiversity-Stability debate • Elton (1958): communities experience more violent fluctuations in population density when they are less diverse. • MacArthur (1955): Species-poor islands and artificial agricultural ecosystems are more prone to invasions by new species and pests than their continental and natural counterparts

vs. • May (1972): Communities with higher diversity tended to be less, not more, stable because higher diversity tend to undermine individual species

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May’s point of view

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Population size

• Models of species interactions with randomly assigned interaction strengths

Time

• Stability = average population size / SD Review in Tilman et al. (2014) Biodiversity and Ecosystem Functioning. Annu. Rev. Ecol. Evol. Syst. 45:471–93

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Biodiversity - Stability Synchrone species

Asynchrone species

• At the community level ➡ Portfolio effect: asynchrony to environmental change

1 species

➡ ~ Insurance hypothesis 2 species

8 species

Loreau, M. (2010). Linking biodiversity and ecosystems: towards a unifying ecological theory. Proc R Soc B, 365(1537), 49-60.

Biodiversity - Stability • Testing the insurance hypothesis in Cedar Creek Productivity stability

Drought resistance

Review in Tilman et al. (2014) Biodiversity and Ecosystem Functioning. Annu. Rev. Ecol. Evol. Syst. 45:471–93

Biodiversity - Stability in space

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𝛼 = No. species present locally β = difference between localities 𝛾 = No. species at the regional scale = 𝛼•β

Wang, S., & Loreau, M. (2014). Ecosystem stability in space: α, β and γ variability. Ecology letters, 17(8), 891-901.

Diameter at breast height (cm)

γ variability CVM2

No. Tree species

Biodiversity - Stability in space

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Area (m2)

➡ Biodiversity temporal variation is important not only locally but also through its spatial heterogeneity Condit, R., et al. (1996). Species-area and species-individual relationships for tropical trees: a comparison of three 50-ha plots. Journal of Ecology, 549-562. Wang, S., & Loreau, M. (2014). Ecosystem stability in space: α, β and γ variability. Ecology letters, 17(8), 891-901.

What about other trophic levels?

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Duffy, J. E., et al. (2007). The functional role of biodiversity in ecosystems: incorporating trophic complexity. Ecology letters, 10(6), 522-538.

Vertical diversity and ecosystem functioning • BEF + food web ecology: adding interactions of species across trophic levels. • Food web ecology relies on graph theory

➡ Network topology features

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Multi-trophic BEF early hypotheses

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• Horizontal diversity effects on other trophic levels: • Top-down control: effects of diversity stronger at higher trophic levels: higher extinction risks

Cardinale, B. J., et al. (2009). Towards a food web perspective on biodiversity and ecosystem functioning. Biodiversity and human impacts, 105-120.

Multi-trophic BEF early hypotheses

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• Horizontal diversity effects on other trophic levels: • Bottom up control: Increasing • Top-down control: effects of diversity of resources reduces the diversity stronger at higher trophic strength of top-down control by levels: higher extinction risks consumers (edibility, dilution, ennemies, balanced diet)

Cardinale, B. J., et al. (2009). Towards a food web perspective on biodiversity and ecosystem functioning. Biodiversity and human impacts, 105-120.

Multi-trophic BEF early hypotheses

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• Diversity effects across trophic levels • Top-down effects of consumer diversity oppose the bottom-up effects of resource diversity • Diversity effects by any focal trophic level
 are reduced in the presence of higher trophic levels

• Trophic cascades are weaker in diverse communities

Cardinale, B. J., et al. (2009). Towards a food web perspective on biodiversity and ecosystem functioning. Biodiversity and human impacts, 105-120.

Food-web constraints on BEF?

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• Nutrient-limited and heterogeneous environment with plants, herbivores that are specialists or generalists Specialists FWC1

H1 … Hn-1

Hn

H1 … Hn-1

Hn

P1 … Pn-1

Pn

P1 … Pn-1

Pn

Generalists FW3

➡ More complex, non-monotonic relationships depending on dietary generalism that are more difficult to predict Thebault, E., & Loreau, M. (2003). Food-web constraints on biodiversity–ecosystem functioning relationships. PNAS, 100(25), 14949-14954.

Food-web constraints on BEF?

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z-scores Level manipulated Plants Herbivores Mycorhiza Decomposers

• Biodiversity always enhances ecosystem functions • Producer diversity positively influences higher trophic levels • Greater stability for certain pressures only Balvanera, P., et al. (2006). Quantifying the evidence for biodiversity effects on ecosystem functioning and services. Ecology letters, 9(10), 1146-1156.

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BEF in a context of extinctions

Ecosystem process

Non-random extinctions?

Natural level Biodiversity

Loreau et al. (2002). Biodiversity and ecosystem functioning: Synthesis and Perspectives,Oxford University Press.

Non-random extinctions

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• Simulation of extinction scenarios for aboveground C stocks • S1: extinction risk: population density / growth rate, endemicity • S2: harvesting strategies: largest populations, selection of hardwoods / largest trees species • S3: environmental change: responses to precipitation, disturbance, elevated CO2 • S4: random extinction Bunker, D. E., et al. (2005). Species loss and aboveground carbon storage in a tropical forest. Science, 310(5750), 1029-1031.

Non-random extinctions

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• Selective logging recruit fast growing species => reduced C storage

Simulation start

• Conversion to plantations with high wood density species would increase carbone storage capacity ➡ Ecosystem processes are determined by the mode and manner in which species are lost Species richness Bunker, D. E., et al. (2005). Species loss and aboveground carbon storage in a tropical forest. Science, 310(5750), 1029-1031.

Non-random extinctions

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• On a multitrophic system: overhunting effects in tropical forests

Large-bodied dispersers

non-endangered

Carbon deficit (Mg/ha) after defaunation simulation

Endangered

Bello, C., et al (2015). Defaunation affects carbon storage in tropical forests. Science advances, 1(11), e1501105.

To sum up

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• Biodiversity increases the efficiency by which ecological communities capture resources, produce biomass, decompose and recycle biologically essential nutrients. • Diverse communities are more productive because they contain key species with large influence on productivity, and differences in functional traits among organisms increase total resource capture. • Biodiversity increases the stability of ecosystem functions through time. • BEF relationship is nonlinear and saturating, such that change should accelerates as biodiversity loss increases. • Loss of diversity across trophic levels has the potential to influence ecosystem functions more strongly than diversity loss within trophic levels. • Functional traits of organisms have large impacts on the magnitude of ecosystem functions => wide range of plausible impacts of extinction on ecosystem function. Cardinale, B. J., et al. (2012). Biodiversity loss and its impact on humanity. Nature, 486(7401), 59-67.

What’s next?

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Cardinale, B. J., et al. (2012). Biodiversity loss and its impact on humanity. Nature, 486(7401), 59-67.

Expanding the focus: what about the belowground?

Direct interactions Mutualistic (e.g. Mycorrhizae) Pathogene infection Root feeding Competition for ressources

Green web ➡ producer-based

Aboveground biota

Organic Matter Input

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CO2, N2

Plant uptake

C Immobilization

Belowground “black box”

Fragmentation/ mineralization

Nutrient pool C/N Mobilisation

Indirect interactions

C leaching

Brown web ➡ detritus-based

Bardgett, R. D., & van der Putten, W. H. (2014). Belowground biodiversity and ecosystem functioning. Nature, 515(7528), 505-511.

Expanding the focus: what about the belowground? Temperate grassland

1 m2

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Meso/Maiofauna: Nematodes: 1,000’s individuals 10,000 individuals 100’s of species 100’s of species

Fungi: 50 km of hyphae 100’s of species Plants: 100g of roots 10’s of species Protozoa: 100,000 cells 100’s of species

*you are here

Archaea: 10 millions cells 100’s of “species”

10,000’s of “species”, mostly microscopic, >95% unknown Bacteria:

100 billions cells 10,000’s of “species”

➡ Low extinction risks? High functional redundancy? Bardgett, R. D., & van der Putten, W. H. (2014). Belowground biodiversity and ecosystem functioning. Nature, 515(7528), 505-511.

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Expanding the focus: one more layer? Environmental change? • Pulse disturbance => punctual • Press disturbance => long term

Species loss?

host performance? Ecosystem processes?

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Link functions to services: the concept of multifunctionality

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• Increasing pressure on dwindling land resources requires to design and manage landscapes that can reliably provide multiple ecosystem services simultaneously. EF-multifunctionality

ES-multifunctionality

Duncan, C., et al. (2015). The quest for a mechanistic understanding of biodiversity–ecosystem services relationships. Proc. R. Soc. B, 282(1817), 20151348.

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Measuring EF multifunctionality • Objectively assess ecosystem functioning without any value judgement • Averaging values on standardised functions ➡ cannot disentangle general trends from opposite trends at intermediate values.

Threshold

Number of functions

• Threshold approach: number of standardised functions that perform above a suit of performance thresholds ➡ sensitivity to the number functions included might affect met analyses outcomes. Functions should be standardised locally. Byrnes, J. E., et al. (2014). Investigating the relationship between biodiversity and ecosystem multifunctionality: challenges and solutions. Methods in Ecology and Evolution, 5(2), 111-124.

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Measuring EF multifunctionality BIODEPTH experiment

Byrnes, J. E., et al. (2014). Investigating the relationship between biodiversity and ecosystem multifunctionality: challenges and solutions. Methods in Ecology and Evolution, 5(2), 111-124.

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Measuring ES multifunctionality • Assessing the supply of ecosystem services relative to human demand 1/Consultation to assess the range of demand

2/Link function to the benefits it provides to humans

3/Measure indicator ecosystem functions on the field

Manning, P., et al. (2018). Redefining ecosystem multifunctionality. Nature ecology & evolution, 2(3), 427.

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Measuring ES multifunctionality • Assessing the supply of ecosystem services relative to human demand Comparison of ES multifunctionality in different land uses and for different stakeholders

Manning, P., et al. (2018). Redefining ecosystem multifunctionality. Nature ecology & evolution, 2(3), 427.

Towards decision support tools?

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Significant repression n.s.

Manning, P., et al. (2018). Redefining ecosystem multifunctionality. Nature ecology & evolution, 2(3), 427.

Towards decision support tools?

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Cardinale, B. J., et al. (2012). Biodiversity loss and its impact on humanity. Nature, 486(7401), 59-67.