Learning, tools and pitfalls of agroecology at landscape scale. Lessons from projects in DYNAFOR Lab.

Learning, tools and pitfalls of agroecology at landscape scale.

Lessons from projects in DYNAFOR Lab.

Ouin, A. 1, 2_{*, Mennozi, P.} 3_{, Monteil, C.} 1, 2_{, Sarthou, J. P.} 1, 2_{, Vialatte, A.} 1, 2_,

Deconchat, M. 2,1

1_{Université de Toulouse, UMR DYNAFOR, INRA/INP-ENSAT/INP-EIPurpan, BP}

32607, 31326 Castanet Tolosan, France.

2_{INRA, UMR DYNAFOR, BP 52627, 31326 Castanet Tolosan, France.} 3_{CIRAD, UPR 10, 34 398 Montpellier, France}

Quels outils pour un changement d'échelle dans la gestion des insectes d’intérêt économique? 4-5 octobre 2011, CIRAD, Montpellier.

1. Why changing scale?

2. Learning from DYNAFOR Lab projects 3. Pitfalls

4. Tools & perspectives Contents

1. Why changing scale?

Changing scale of observation = Changing the dominant phenomena controlling the pattern

extent

10 m

100 m

Insect sampling: abundance in 0.1 m2 _(grain)

Question: predator / Prey abundances at

different sampling scales in forest leaf litter?

1. Why changing scale?

Fine scale = predator avoidance

0 5 10 15 20 25 30 35 10 15 20 25 30 35 40 45 Predators P re y Grain = 0.1m2_{, Extent = 100m}

1. Why changing scale?

Large scale = predator and prey have similar ecological requirements (leaf litter more abundant in forest area than in crop)

0 5 10 15 20 25 30 35 40 45 0 5 10 15 20 25 30 Predators P re y Grain = 10 m2_{, Extent = 10 000m}

1. Why changing scale?

Most of insect of economic interest are mobile: Pests & Beneficial insects ( more or less…)

Predators,parasites, pollinators = MABES: Mobile-Agent-Based Ecosystem Services (sensu Kremen et al., 2007)

2. Learning from DYNAFOR Lab Project

We are not a « crop protection » Lab.

Studies at different scales: Wood density

Emergence of beneficial insects (carabids and others) from woods and other semi-natural elements

2. Learning from DYNAFOR Lab Project: Wood density

How can woodlots contribute to crop protection? By promoting natural enemies of pest (aphids)

Providing shelter (against cold or hot weather) Being stable elements of rural landscapes

(recolonisation of the landscape)

Main Hypothesis:

Landscapes with higher woodlot cover provide a more efficient crop protection than less wooded landscapes

The studied species

Episyrphus. balteatus larva : one of the most efficient predator of

cereal aphids

E. balteatus adult : - ubiquitous "flower fly"  nectar and pollen

feeding

- active females overwinter in southern Europe

The sooner aphidophagous insects set up in crops  the greater the

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abundance?

Study sites

LTSER site Gascony Valleys & Hills

Increasing wood

density Wooded: 27%

Less wooded: 15%

10 Km

•6-7 Sampling of wheat stalk from April to June (2003 to 2007) •7 crop fields per landscape

•1 sampling square (unsprayed) per field •10 bags of 10 stalks per squares

1 400 stalks per sampling date

Wheat field

Crop edge (Hedge, wood, field margin) Sampling square

20 m

25 m

N

The Hover-Winter model

A multi-agent model of winter

survival was developed, on

CORMAS platform (Arrignon et al. 2007).

It predicts the abundance of

hoverfly at the end of the winter, according to:

Winter temperature,

Landscape composition and

structure, Individual behaviour. Shel te r Wood Flowers _Temperature

Arrignon, F., Deconchat, M., Sarthou, J.P., Balent, G., & Monteil, C. 2007. Modelling the overwintering strategy of a beneficial insect in a heterogeneous landscape using a multi-agent system. Ecological Modelling, 205, 423-436.

The Hover-Winter model

Arrignon, F., Deconchat, M., Sarthou, J.P., Balent, G., & Monteil, C. 2007. Modelling the overwintering strategy of a beneficial insect in a heterogeneous landscape using a multi-agent system. Ecological Modelling, 205, 423-436.

Arrignon, F., Deconchat, M., Sarthou, J.P., Balent, G., & Monteil, C. 2007. Modelling the overwintering strategy of a beneficial insect in a heterogeneous landscape using a multi-agent system. Ecological Modelling, 205, 423-436.

Results: No significant difference between wooded & non wooded landscape for hoverflies (eggs & larvae)

A significant year effect (P<0.01)

-20 0 20 40 60 80 100 2003 2004 2005 2006 2007 -500 0 500 1000 1500 2000 2500 3000

ANOVA: co-variable: aphids, A significant effect of the year (P<0.01) * The fourth first sampling (~April-May)

Results: A significant difference between wooded & non wooded landscape for hoverflies (eggs & larvae) in early spring*

0 10 20 30 40 50 60 2003 2004 2005 2006 2007 Year e a rl y a v e ra g e a b u n d a n c e o f h o v e rfl ie s (e g g s + la rv a e )

Wooded landscape Less wooded landscape

**

** **

**

Results: An hoverflies / aphids ratio not always greater in wooded landscape... -10 0 10 20 30 40 50 2003 2004 2005 2006 2007 Year H o v e rf li e s / a p h id s * 1 0 0

Results: A positive effect of wooded landscape for winter (simulation) not always confirmed by early spring abundance in the field

0 1 2 3 4 5 6 woo d1 woo d2 Less Wd1 Less Wd2 woo d1 woo d2 Less Wd1 Less Wd2 woo d1 woo d2 Less Wd1 Less Wd2 Si m u la te d w in te r s u rv iv a l ra te (% ) -5 0 5 10 15 20 25 30 35 40 s p ri n g a b u n d a n c e o f s y rp h id s i n w h e a t fi e ld s

Survival rate Syphids

Is there more E. balteatus and less aphids in wheat crops surrounded by woodlots?

Yes, in early spring only, then they are everywhere whatever the landscape

Back to the questions

A threshold of 30% of woodlots in the landscape seems necessary to get the early spring effect.

Do woodlots help winter survival & support early spring E. balteatus abundance?

Sometimes yes, in addition to flower patches (meadows, hedges) in the vicinity.

Back to the questions

The complementation between woodlots & flower patches in the landscape seems

necessary to improve winter survival of adult females.

2. Learning from DYNAFOR : Emergence of beneficial insects

© Roy Anderson © J.M Silberreiss © Roy Anderson © Roy Anderson

What is the spatial distribution of overwintering field ground beetles in woodlots regarding:

the distance from the edge?

Roume, A. , Ouin, A., Raison, L., Deconchat, M., 2011 Higher abundance and species richness of ground beetles (Coleoptera: Carabidae) overwintering in the edge than in the centre of a woodlot. European Journal of Entomology 108: 615-622

2. Learning from DYNAFOR : Emergence of beneficial insects

Upper recipient for flying insects

Pitfall trap for walking insects Walls buried into the soil Total area: 1,8 m²

2. Learning from DYNAFOR : Emergence of beneficial insects

• 11 ha woodlot

• 45 emergence traps • Placed relatively to:

– Distance from edge (0 m; 25-50 m; >75 m)

• Traps activated from March to October 2008 N 100 m Fallow land Rape field Grassland

2. Learning from DYNAFOR : Emergence of beneficial insects

Ground beetles density (/m²)

1 5 25 125

Number of species per trap

1 3 10 25

• 2014 ground beetles collected, from 48 species

Density of ground beetles (m-2₎

0 m 25-50 m >75 m 0 20 40 60 80 100 120 140

Distance from woodlot edge

G ro u n d b e e tle d e n si ty ( /m ²) p-value = 3.4e-05

2. Learning from DYNAFOR : Emergence of beneficial insects

• Higher density in edges, whatever the adult habitat

• During spring, 2/3 of individuals trapped in edges belong to open habitat species 0 m 25-50 m >75 m 0 10 20 30 40 50 Forest species (n=711, s=3) Kruskal-Wallis test p=0.1 0 m 25-50 m >75 m 0 10 20 30 40 50 Generalist species (n=706, s=12) Kruskal-Wallis test p=0.00042 0 m 25-50 m >75 m 0 10 20 30 40 50

Open habitat species (n=324, s=21)

Kruskal-Wallis test p=1.2e-05

Distance from woodlot edge

Abs ol ute dens ity (nb of indi v iduals.m -2 )

2. Learning from DYNAFOR : Emergence of beneficial insects 0 m 25-50 m >75 m 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Predatory species (n=1374, s=18) Kruskal-Wallis test p=0.022 0 m 25-50 m >75 m 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Polyphagous species (n=429, s=4) Kruskal-Wallis test p=0.0058 0 m 25-50 m >75 m 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Phytophagous species (n=100, s=7) Kruskal-Wallis test p=0.32 Edge 25-50 m >75 m

Pred Poly Phyto

0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Predatory species (n=1374, s=18) Kruskal-Wallis test p=0.32

Pred Poly Phyto

0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Polyphagous species (n=429, s=4) Kruskal-Wallis test p=0.0058

Pred Poly Phyto

0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Phytophagous species (n=100, s=7) Kruskal-Wallis test p=0.32 Feeding mode Rel ati v e abundanc e

Feeding mode of adults:

• Predatory n=1374 s=18

• Polyphagous n=429 s=4

2. Learning from DYNAFOR : Emergence of beneficial insects

2. Learning from DYNAFOR : Emergence of beneficial insects Beneficial carabids Crops Hedges Wood edges Grasslands

2. Learning from DYNAFOR : Complex of beneficials insects

ANR Systerra Landscaphid 2010-2013 Landscape suppresiveness on aphids

Groupes d’auxiliaires

considérés

Syrphes

aphidiphages Chrysopes Entomophtorales Coccinelles

Hyménoptères parasitoïdes pupes et œufs œufs adultes, larves et œufs momies pleines

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0 100 200 300 400 500 Coef . c orré latio n R² Echelles spatiales (m) Oeufs chrysopes ~ Surface

friches 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0 100 200 300 400 500 Coef . corr éla tio n R² Echelles spatiales (m)

Coccinelles adultes ~ Surface friches

But…

2. Learning from DYNAFOR Lab Projects

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3. Pitfalls

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4. Tools & perspectives

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4. Tools & perspectives

Spatial dynamics of a cotton pest moth Helicoverpa armigera in Western Africa to improve the use of ecosystem services.

Noelline Tsafack (PhD student, CIRAD) Tools:

Microbial DNA Isotopes (D, C, N)

Biochemical markers (Gossypol, Tomatine)

4 landscapes along a gradient of cotton crop density ( landscape based sampling design), 5 cotton fields in each landscape (+ 1 landscape)

Question:

From where do the moths come from when they arrive in the cotton field (Ocotober)?

Long distance (migration) Backyard

No or few landscape effect Landscape effect (landscape analysis)

Many thanks to :

Colleagues, Technical staff and volunteers :

B. Bouyjou, L. Burnel, L. Raison, J. Willm Marc Fakorellis, Wilfried Heintz, V. Guyot

The students:

2003: G. Belhoute, A. Etienne

2004: S. Ledoux, Y. Allouche, E. Vintrou, A. Guellerin

2005: N. Bastin, A. Montupet, A. Chevalier, F. Roussel, C. Jaubertie 2006: V. Robbe

2007: M. Coulon, N. Bastin, P. Lacapelle 2008: M. Redon

2009: G. David