Presentation for the talk I gave at the European Ecological Federation conference in Rome in September 2015

1. Introduction Methods Results Discussion
Increase in Predation Rates along an Experimental
Plant Diversity Gradient
Lionel Hertzog
Anne Ebeling
Sebastian Meyer
Wolfgang Weisser

2. Introduction Methods Results Discussion
Impacts of Predation on communities and
ecosystems
keepwolveslisted.blogspot.de

3. Introduction Methods Results Discussion
Impacts of Predation on communities and
ecosystems
keepwolveslisted.blogspot.de
Pearson Education

4. Introduction Methods Results Discussion
Theoretical relationships between plant diversity and
predation
Exploitative ecosystem hypothesis Oksanen 1981
Marquard et al 2009 zoologi.su.se

5. Introduction Methods Results Discussion
Theoretical relationships between plant diversity and
predation
Structural hypothesis
Gotceitas 1989

6. Introduction Methods Results Discussion
Questions
1 What is the effect of plant diversity and plant biomass on
predation rates?

7. Introduction Methods Results Discussion
Questions
1 What is the effect of plant diversity and plant biomass on
predation rates?
2 What is the effect of season and position on predation rates?

8. Introduction Methods Results Discussion
Field Site

9. Introduction Methods Results Discussion
Sown Plant Species

10. Introduction Methods Results Discussion
Baits
Aphids Larvae
Dummy

11. Introduction Methods Results Discussion
Design: Baits
Days of the experiment Σ
1 2 3 4 5 6 7
Aphids - - - 2 2 3 3 10
Larvae
3 4 3 2 3 2 3 20
4 3 3 3 2 3 2 20
Dummy
2 2 1 2 1 1 1 10
1 1 3 1 2 1 1 10
Σ 10 10 10 10 10 10 10 70

12. Introduction Methods Results Discussion
Design: Spatial Replication
N = 80

13. Introduction Methods Results Discussion
Some numbers
Proportion of removed baits (aphids + larvae) and of dummy with
bite marks:
May August
Aphids 0.72 0.48
Larvae
0.54 0.17
0.86 0.55
Dummy
0.07 0.11
0.23 0.34

14. Introduction Methods Results Discussion
Some numbers
May August
Gasteropods
3.8 2.5
17.6 13.4
Insects (bites)
4.3 6.3
8.1 20.9
Mammals
0.3 1.4
0.4 5.7
Birds
0.6 0.0
0.3 0.1

15. Introduction Methods Results Discussion
Effect of Biomass
Ground Vegetation

16. Introduction Methods Results Discussion
May on the ground

17. Introduction Methods Results Discussion
August on the ground

18. Introduction Methods Results Discussion
May in the vegetation

19. Introduction Methods Results Discussion
August in the vegetation

20. Introduction Methods Results Discussion
Effect of vertebrate predation in May

21. Introduction Methods Results Discussion
Plant diversity effect on predation
Effect of plant diversity interacting with season and layer
Phenology of prey and predator communities
Different groups of predator between ground and vegetation
Without vertebrate predation positive plant diversity effect on
the ground

22. Introduction Methods Results Discussion
Plant biomass effect on predation
Weak biomass effect
Only negative effects in May for larvae
Might be correlated with vegetation complexity

23. Introduction Methods Results Discussion
Summary
1 Variation in predation between ground and vegetation layer

24. Introduction Methods Results Discussion
Summary
1 Variation in predation between ground and vegetation layer
2 Without vertebrate predation consistent increase of predation
with plant diversity on the ground

25. Introduction Methods Results Discussion
Summary
1 Variation in predation between ground and vegetation layer
2 Without vertebrate predation consistent increase of predation
with plant diversity on the ground
3 Predator phenology render relationships complex

26. Introduction Methods Results Discussion
Summary
1 Variation in predation between ground and vegetation layer
2 Without vertebrate predation consistent increase of predation
with plant diversity on the ground
3 Predator phenology render relationships complex
4 No support for the exploitative hypothesis

27. Introduction Methods Results Discussion
Summary
1 Variation in predation between ground and vegetation layer
2 Without vertebrate predation consistent increase of predation
with plant diversity on the ground
3 Predator phenology render relationships complex
4 No support for the exploitative hypothesis
5 Potential support for the structural complexity hypothesis

28. Introduction Methods Results Discussion
Future direction

29. Introduction Methods Results Discussion
The thank you slide
Ilka Wolf
Sylvia
Creutzburg
Gerlinde
Kratzsch
Silke
Schroekh
Diana von
Unruh
Heike
Scheffler
Silke
Hengelhaupt
Ute K¨ober
Many
student
helpers
DFG for
funding

30. Introduction Methods Results Discussion

31. Introduction Methods Results Discussion