Effet de l'hétérogénéité de la mosaïque des cultures sur la biodiversité et les SE des paysages agricoles. Clélia Sirami DYNAFOR-INRA, Toulouse

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1 Effet de l'hétérogénéité de la mosaïque des cultures sur la biodiversité et les SE des paysages agricoles Clélia Sirami DYNAFOR-INRA, Toulouse

2 Positive effect Low policy effectiveness Higher policy effectiveness Effect Unknown

3 European network on crop heterogeneity, biodiversity and ecosystem services Call 3/3/212-3/3/

4 Biodiversity Context Project aims Methods Results Ecosystem services Implications Guideline co-construction Crop Diversity Common Mental Model BD ES Mean Field Size Practices Individual Mental Model

5 Biodiversity Context Project aims Methods Results Ecosystem services Implications Guideline co-construction Crop Diversity Common Mental Model BD ES Mean Field Size Practices Individual Mental Model

6 8 study regions in 5 countries

7 Common protocols 1. Landscape selection (1 x 1km) - 6-9% crop - 4 landscapes per region - 2 idpt gradients CD / MFS Pasher et al. (215)

8 Common protocols 2. Sampling sites - 3 sites per landscape - similar crops - similar boundary types

9 Common protocols 3. Biodiversity/Ecosystem services 25 m 4 m 5 m + bats, amphibians, springtails, mites, ants

10 Fieldwork in figures 435 landscapes, 135 fields 8 farmers 18 m² sampled (plants) 27 km transect butterfly 43 2 traps 81 aphids glued 167 specimens identified species identified

11 Crop heterogeneity gradients PVDS Coteaux East Anglia Ontario Armorique Goettingen Lleida Camargue Different gradients => wider gradient across regions Overlapping gradients => testing generality of effects

12 Weak correlation between taxa Mean SR bird bee butterfly carabid hoverfly plant bird 18.7±6.7 bee 11.2± butterfly 5.4± carabid 12.3± *.16** hoverfly 6.4± plant 44.9± spider 2.6± *.41*** -.17**.38***.17***.5 Species richness per landscape (3 fields)

13 Taxon 2 Species diversity Taxon 3 Species diversity Taxon 1 Species diversity Context Project aims Methods Results Implications Taxon 3 Scaled Species diversity Taxon 1 Scaled Species diversity Taxon 2 Scaled Species diversity Multidiversity A synthetic index of biodiversity: Multidiversity scaling Heterogeneity scaling Heterogeneity average Heterogeneity Heterogeneity Heterogeneity scaling Heterogeneity Heterogeneity Allan et al. (214)

14 Effects of crop heterogeneity = or > effects of SNC Interactive Effects Semi- Natural Cover Crop Number Crop Heterogeneity MFS = Mean Field Size; CD = Crop Diversity; SNC=% Semi-Natural Cover; CropNb = Crop number

15 Hedgerow Context Project aims Methods Results Implications Land Use Intensity Crop Diversity Crop mosaic composition Effects of crop heterogeneity not explained by other factors Crop diversity Crop type sampled Mean Field Size Crop diversity

16 Effects are strongly landscape-dependent NC 5% SNC 5% SNC 15% SNC 15% SNC 25% SNC 25% Multidiversity Crop Diversity Mean Field Size Crop Diversity Mean Field Size Crop Diversity Crop Diversity Mean Field Size Crop Diversity -.6 Mean Field Size Crop Diversity Mean Field Size 2 1 Mean Field Size Low semi-natural cover CD AND MFS High semi-natural cover CD OR MFS

17 CD and MFS affect different types of predators AUTUMN BREEDERS most of them overwinter in the fields as larvae SPRING BREEDERS hibernate as adults in surrounding noncrop habitats Bertrand et al. (216a, 216b)

18 Decreasing MFS only decreases aphid density if Fields are bordered by grassy boundary Bosem Baillod et al. (217)

19 Increasing CD only decreases aphid density if their habitat is lower than the year before Bosem Baillod et al. (217)

20 Hass et al. (submitted) Small fields favour wild bees, and increase pollination

21 Policies on crop heterogeneity are effective ways to: Improve BD conservation Maintain area, yield, production Maintain TE, limit costs, maintain farmers income Favour crop mosaic species, ecosystem services Higher uptake Agricultural policies should combine incentives for: 1) CD AND MFS simultaneously 2) crop diversity AND crop rotation 3) specific crop types 4) SNC and SNL (hedgerows and grassy margins)

22 Effet de l'hétérogénéité de la mosaïque des cultures sur la biodiversité et les SE des paysages agricoles