The ecological consequences of individual-level variation across scales


General topics:
A. Theoretical ecology
B. Ecological modelling
C. Biodiversity theory
D. Statistics
E. Scientific writing and presentation

Didactic focus:
I. Student orientation
II. Interaction & Activation
III. Theory games
IV. Research-based learning
V. Project-based learning

Introductory Courses*:
• Ökosystemmodellierung (in German, 700322, BSc Ökosystemmanagement, winter) A, B, E, I, II, III, (IV)
• Ecological Modelling (700406, BSc Molecular Ecosystem Sciences, winter) A, B, I, II, III, (IV)
• Statistik in der Biodiversitätsforschung (in German, 631824, BSc Biodiversität, Block, winter) C, D, E, I, II, III, IV, V
• Wissenschaftliches Arbeiten (in German, 700463, BSc Forst, summer): scientific writing and presentation, statistics with R D, E, I, II, IV, V

Advanced Courses*:
• Ecological Simulation Modelling (new; MSc Forest and Ecosystem Science, based on earlier German course Simulationsmodelle, 700292, MSc, summer) (A), B, (E), I, II, IV
• Agent-based modelling with NetLogo (700268, BSc/MSc/PhD, block in summer) (A), B, (E), I, II, IV, V
• Biodiversitätstheorien (in German, 700332, MSc Forst, winter) A, C, (E), I, II, III, V
• Statistical Data Analysis with R (700531, MSc Forest and Ecosystem Science, winter) D, I, II
• Manuscript Seminar (700295, MSc/PhD, summer) E, I, II, IV, V

* Courses designed by me, often carried out together with colleagues

Selected student feedbacks:
Ecological Modelling (BSc, online) - Halftime-Feedback, winter 2020/21
Agent-based modelling with NetLogo (MSc, on site) - Feedback, SoSe 2019

Teaching materials:
Materiales for an online experiment about MacArthur & Wilson's island biogeography theory (example of a theory game): zip-file


Research Interests:
Terrestrial ecology
ecological concepts in micro- and macroecology, individual interactions, savanna ecology, cyclical succession, multitrophic interactions, above-belowground interactions, plant behaviour, bacterial interactions in the phyllosphere, tropical ecology

Individual-based modelling
simulation modelling with NetLogo, agent-based modelling, trait-based modelling, scaling-up, population viability analysis, combined empirical-modelling approaches, pattern-oriented modelling, sensitivity analysis

Spatial ecology
patch dynamics, spatial root and shoot competition, grid-based modelling, spatial statistics

My Researcher-ID: E-6839-2013


2009 - Senior Lecturer, Göttingen University
2006 - 2008 Postdoc, NIOO-KNAW, Netherlands
2003 - 2006 PhD, Jena University
2000 - 2001 Student, Imperial College London
1997 - 2003 Diploma in Biology, Marburg University


2021 Ars legendi-Fakultätenpreis Biowissenschaften (teaching award)
2012 Campusemerge, 1st prize
2012 Goettingen Award for Forest Ecosystems Research


My past and present projects investigate the consequences of individual-level variation or ecological patterns at larger spatial, temporal, and organizational scales [16,17,21, 32, 37, 47, 48]:

Climate change-induced invasionsTrait-based modelling of population and community dynamics
Under climate change, the invasion success of range-shifting plants may depend on the traits of the potential invaders and their competitors and enemies [40]. We are developing trait-based and often scale-explicit models where population dynamics emerge from individual interactions in a field-scale grid of a few hectares [38]. These interactions are influenced by plant and animal traits [42, 46]. Local results can be extrapolated to a regional-scale grid. One model result is that traits conferring strong dispersal abilities can be the key to the invasive success of range-expanding plants under climate change, but only if 'guerilla' plants are not impeded by fast enemies [Meyer et al., in prep.].
> PhD student Liubov Zakharova
> PhD thesis Janina Radny
> MSc thesis Mijke van Oorschot ("cum laude")
> MSc thesis Tanja Gerbershagen
> in cooperation with Wim van der Putten, Netherlands Institute of Ecology NIOO-KNAW, The Netherlands, Katja Tielbörger, University of Tübingen, Germany, and Merav Seifan, Ben-Gurion University, Israel
> funded by the German Research Foundation DFG and by the Volkswagen Foundation

Bacteria on leafEcological concepts and bacterial individuality in the phyllosphere
A few ecological concepts and theories such as the niche or island biogeography theory have been applied to bacterial communities on leaf surfaces, but there is scope for many more such tests of macroecological concepts in microbiomes such as the phyllosphere [22]. The phyllosphere is also highly suitable to investigate bacterial interactions across spatial and organizational scales. We succeeded in quantifying the scales of spatial interactions among bacteria and between bacteria and the leaf surface [30]. There is a broad range of approaches to model microbial growth and dynamics in the phyllosphere and other microbial ecosystems. These modelling approaches should be combined more often in the future [31].
> PhD thesis Daniel Esser ("summa cum laude")
> PhD student Matthias Fritsch
> BSc thesis Anna Hille
> in cooperation with Johan Leveau, University of California at Davis, USA, and Netherlands Institute of Ecology NIOO-KNAW, The Netherlands
> funded by the Dutch research foundation NWO and the German Research Foundation DFG (subproject in RTG 1644)

RainForestMarginSulawesiIntegrated modelling of land-use changes in Indonesia
In these projects, we develop and analyze integrated models of land-use change at rainforest margins [24, 27] and in transformation systems [39] in Indonesia. We model the gradient of land-use types from natural and logged forest to agroforestry and transformed systems such as oil palm plantations [see also 36, 44]. A grid-based ecological model is complemented by a socio-economic, agent-based model component that simulates the dynamics of individual households. Overall, the model analyses will improve our understanding of ecological and socio-economic trade-offs [33] under land-use change.
> Postdocs Jan Salecker, Johannes Heinonen, Claudia Dislich and Rodolphe Sabatier
> PhD thesis Elisabeth Hettig
> MSc thesis Andreas Spangenberg
> in cooperation with Kerstin Wiegand and Jann Lay
> funded by the German Research Foundation DFG (Subprojects in ELUC and CRC 990)

NIOO-GreenhouseHigher trophic levels can influence plant biomass
Our individual-based community simulation model ABBE showed that interactions between a crop plant, its herbivores, and higher trophic levels were stronger belowground than aboveground and that higher trophic levels indirectly affected plant biomass [13]. We also show that simulating experiments based on experimental data from the greenhouse can help to overcome sample size constraints of empirical studies [12]. This illustrates the importance of intense collaboration between empiricists and modellers in above-belowground interactions research [10, 25]. ABBE was also used to assess the relative importance of above- and belowground multitrophic interactions for plant performance along a gradient from natural to agricultural conditions. Belowground interactions were more important towards natural conditions and aboveground interactions more towards crops [23]. A parallel greenhouse experiment highlighted the importance of rare species [18] and the influence of nematodes on aphid-plant interactions [26, 34]. I give an overview of modelling aboveground and belowground interactions in a book chapter [41].
> in cooperation with Wim van der Putten, Wolf Mooij, Matthijs Vos, and Gera Hol, Netherlands Institute of Ecology NIOO-KNAW, The Netherlands
> funded by the Dutch Research Foundation NWO

SavannaSavannas got rhythm
To test patch dynamics as a new scale-explicit mechanism for tree-grass coexistence in savannas at the patch level, we developed the spatially explicit grid- and individual-based SAvanna paTCH MOdel SATCHMO [6]. The exceptional strength of this model is its successful validation against empirical field data [1,5,8]. Cyclical successions of trees and grasses consistently emerged from the SATCHMO simulations, supporting the applicability of patch-dynamics to savannas [5,6,9,11,15]. To complement our model, we have combined and analysed several techniques from spatial statistics [19] to derive a new scale-crossing method for the determination of patch size in vegetation ecology [4]. Further analyses and models of spatial patterns in semi-arid regions followed in cooperation projects [35, 45].
> in cooperation with Kerstin Wiegand at Jena University, Germany, and David Ward at University of KwaZulu-Natal, South Africa, (now Kent State University, USA), as well as Yousef Erfanifard, Shiraz, Iran
> funded by the German Research Foundation DFG and the Volkswagen Foundation

CrayfishPopulation viability analysis
We compared different viability measures in a systematic way [50] and explore metapopulation viability in a case study of black poplar populations (PhD thesis Salecker). To assess the viability of noble crayfish populations, we developed an individual-based simulation model including age-dependent mortalities. We scaled individual interactions up to population-level extinction patterns. The simulations yielded low mean times to extinction. The sensitivity analysis provided evidence against the established view that the noble crayfish is a K-strategist [3].
> PhD student Jan Salecker (ongoing)
> MSc thesis Mario Trouiller (co-supervised by G. Pe'er; Leipzig)
> crayfish study in cooperation with Roland Brandl and Knut Gimpel at Marburg University, Germany

Berberis vulgarisPlants show complex behaviour
Using a pattern-oriented simulation model, we demonstrated complex plant behaviour mediated by seed abortion in Berberis vulgaris [29]. Mortality of individual seeds was scaled up to fruit type distribution patterns.
> in cooperation with Hans-Hermann Thulke and Harald Auge at the Helmholtz-Centre for Environmental Research UFZ, Leipzig, Germany
> funded by the Helmholtz-Centre for Environmental Research UFZ

My work at Göttingen University was also partly funded by the Cluster of Excellence "Functional Biodiversity Research".

50. Trouillier, M.,Meyer, K.M., Santini, L., Pe’er, G. (2023) A comparison of population viability measures. Ecology and Evolution: 13, e9752.

49. Roeder, M., Meyer, K.M. (2022) English Ivy (Hedera helix) is fast, but ash (Fraxinus excelsior) too: Decomposition of English Ivy litter compared to four common host trees - a multisite citizen sciences project. Acta Oecologica 115, 103832.

48. Udy, K., Fritsch, M., Meyer, K.M., Grass, I., Hanß, S., Hartig, F., Kneib, T., Kreft, H., Kukunda, C.B., Pe'er, G., Reinighaus, H., Tietjen, B., Tscharntke, T., van Waveren, C.-S., Wiegand, K. (2021) Environmental heterogeneity predicts global species richness patterns better than area. Global Ecology and Biogeography 30: 842-851.

47. Fritsch, M., Lischke, H., Meyer, K.M. (2020) Scaling methods in ecological modelling. Methods in Ecology and Evolution 11: 1368– 1378. Recommended in FacultyOpinions: 10.3410/f.738836856.793579364.

46. Zakharova, L., Meyer, K.M., Seifan, M. (2020) Combining trait- and individual-based modelling to understand desert plant community dynamics. Ecological Modelling 434: 109260.

45. Hess, B., Dreber, N., Liu, Y., Wiegand, K., Ludwig, M., Meyer, H., Meyer, K.M. (2020) PioLaG: a piosphere landscape generator for savanna rangeland modelling. Landscape Ecol. 35, 2061–2082.

44. Salecker, J., Dislich, C., Wiegand, K., Meyer, K.M., Pe'er, G. (2019) EFForTS-LGraf: A Landscape Generator for Creating Smallholder-Driven Land-Use Mosaics. PLoS ONE 14(9): e0222949.

43. Salecker, J., Sciaini, M., Meyer, K.M., Wiegand, K. (2019) The nlrx R package: A next-generation framework for reproducible NetLogo model analyses. Methods in Ecology and Evolution, 10: 1854–1863. 2019, doi: 10.1111/2041‐210X.13286.

42. Zakharova, L., Meyer, K.M., Seifan, M. (2019) Trait-based modelling in ecology: a review of two decades of research. Ecological Modelling 407,

41. Meyer, K.M. (2018) Modeling Aboveground–Belowground Interactions. In: Ohgushi, T., Wurst, S., Johnson, S.N. (Eds) Aboveground-Belowground Community Ecology. Ecological Studies 234. Springer.

40. Radny, J., van der Putten, W.H., Tielbörger, K., Meyer, K.M. (2018) Influence of seed size on performance of non-native annual plant species in a novel community at two planting densities. Acta Oecologica 92, 131-137.

39. Dislich, C., Hettig, E., Salecker, J., Heinonen, J., Lay, J., Meyer, K.M., Wiegand, K., Tarigan, S. (2018) Land-use change in oil palm dominated tropical landscapes - An agent-based model to explore ecological and socio-economic trade-offs. PLOS ONE, 13(1): e0190506;

38. Radny, J., Meyer, K.M. (2018) The role of biotic factors during plant establishment in novel communities assessed with an agent-based simulation model. PeerJ 6:e5342

37. Li, Y., Brose, U., Meyer, K.M., Rall, B.C. (2017) How patch size and habitat complexity changes interaction strength and population dynamics: a combined individual-based and population-based modeling experiment. PeerJ 5:e2993; DOI 10.7717/peerj.2993

36. Dislich, C., Keyel, A.C., Salecker, J., Kisel, Y., Meyer, K.M., Auliya, M., Barnes, A.D., Corre, M.D., Darras, K., Faust, H., Hess, B., Klasen, S., Knohl, A., Kreft, H., Meijide, A., Nurdiansyah, F., Otten, F., Pe'er, G., Steinebach, S., Tarigan, S., Tölle, M.H., Tscharntke, T., Wiegand, K. (2017) Ecosystem functions of oil palm plantations: a review. Biological Reviews 92, 1539–1569.

35. Erfanifard, Y., Saborowski, J., Wiegand, K., Meyer, K.M. (2016) Efficiency of sample-based indices for spatial pattern recognition of wild pistachio (Pistacia atlantica) trees in semi-arid woodlands. Journal of Forestry Research 27, 583-594, doi:10.1007/s11676-015-0205-y.

34. Hol, W.H.G., Raaijmakers, C.E., Mons, I., Meyer, K.M., van Dam, N. (2016) Root-lesion nematodes suppress cabbage aphid population development by reducing aphid daily reproduction. Frontiers in Plant Science 7, 111, doi: 10.3389/fpls.2016.00111

33. Klasen, S., Meyer, K.M., Dislich, C., Euler, M., Faust, H., Gatto, M., Hettig, E., Melati, D.N., Jaya, I.N.S., Otten, F., Pérez-Cruzado, C., Steinebach, S., Tarigan, S., Wiegand, K. (2016) Economic and ecological trade-offs of agricultural specialization at different spatial scales. Ecological Economics 122, 111-120. Doi: 10.1016/j.ecolecon.2016.01.001

32. Singer, A., Johst, K., Banitz, T., Fowler, M.S., Groeneveld, J., Gutierrez, A.G., Hartig, F., Krug, R.M., Liess, M., Matlack, G., Meyer, K.M., Pe'er, G., Radchuk, V., Voinopol-Sassu, A.-J., Travis, M.J. (2016) Community dynamics under environmental change: how can next generation mechanistic models improve projections of species distributuions? Ecological Modelling 326, 63-74. Doi: 10.1016/j.ecolmodel.2015.11.007

31. Esser, D.S., Leveau, J.H.J. & Meyer, K.M. (2015) Modeling microbial growth and dynamics. Applied Microbiology and Biotechnology 99, 8831-8846, DOI 10.1007/s00253-015-6877-6.

30. Esser, D.S., Leveau, J.H.J., Meyer, K.M. & Wiegand, K. (2015) Spatial scales of interactions among bacteria and between bacteria and the leaf surface. FEMS Microbiology Ecology, 91 (3), doi: 10.1093/femsec/fiu034.

29. Meyer, K.M., Soldaat, L.L., Auge, H. & Thulke, H.-H. (2014) Adaptive and selective seed abortion reveals complex conditional decision making in plants. American Naturalist 183, 376-383, DOI 10.1086/675063.

28. Accatino F., Sabatier R., De Michele C., Ward D., Meyer K.M. & Wiegand K. (2014) Robustness and management adaptability in tropical rangelands: a viability-based assessment under the non-equilibrium paradigm. Animal 8, 1272-1281.

27. Sabatier R., Wiegand K., Meyer K. (2013) Effects of two extreme types of management strategies on production and robustness of a Cacao agroecosystem. PLoS One,

26. Hol, W.H.G., de Boer, W., Termorshuizen, A.J., Meyer, K.M., Schneider, J.H.M., van der Putten, W.H. & van Dam, N.M. (2013) Heterodera schachtii nematodes interfere with aphid-plant relations on Brassica oleracea. Journal of Chemical Ecology 39, 1193-1293.

25. Jeltsch, F., Blaum, N., Brose, U., Chipperfield, J.D., Clough, Y., Farwig, N., Geissler, K., Graham, C.H., Grimm, V., Hickler, T., Huth, A., May, F., Meyer, K.M., Pagel, J., Reineking, B., Rillig, M.C., Shea, K., Schurr, F.M., Schröder, B., Tielbörger, K., Weiss, L., Wiegand, K., Wiegand, T., Wirth, C. & Zurell, D. (2013) How can we bring together empiricists and modellers in functional biodiversity research? Basic and Applied Ecology 14, 93-101.

24. Sabatier, R., Meyer, K.M., Wiegand, K. & Clough, Y. (accepted) Non-linear effects of pesticide application on biodiversity-driven ecosystem services and disservices in a cacao agroecosystem: a modeling study. Basic and Applied Ecology 14, 115-125.

23. Meyer, K.M., Vos, M., Mooij, W.M., Hol, W.H.G., Termorshuizen, A.J. & van der Putten, W.H.G. (2012) Testing the paradox of enrichment along a land use gradient in a multitrophic aboveground and belowground community. PLoS One 7,

22. Meyer, K.M. & Leveau, J.H.J. (2012) Microbiology of the phyllosphere: a playground for testing ecological concepts. Oecologia 168, 621–629.

21. Scherber, C., Lavandero, B., Meyer, K.M., Perovic, D., Visser, U., Wiegand, K. & Tscharntke, T. (2012) Scale effects in biodiversity and biological control: methods and statistical analysis. In: Gurr, G.M., Wratten, S.D., Snyder, W.E., Read, D.M.Y. (eds) Biodiversity and Insect Pests: Key Issues for Sustainable Management. John Wiley & Sons.

20. Hol, W.H.G., Meyer, K.M. & van der Putten, W.H. (2011) Idiosyncrasy in ecology - What's in a word? Frontiers in Ecology and the Environment 9, 431-433.

19. Schleicher, J., Meyer, K.M., Wiegand, K., Schurr, F.M. & Ward, D. (2011) Disentangling facilitation and seed dispersal from environmental heterogeneity as mechanisms generating associations between savanna plants. Journal of Vegetation Science 22, 1038-1048.

18. Hol, W.H.G., de Boer, W., Termorshuizen, A.J., Meyer, K.M., Schneider, J.H.M., van Dam, N.M., van Veen, J.A. & van der Putten, W.H. (2010) Reduction of rare soil microbes modifies plant-herbivore interactions. Ecology Letters 13, 292-301.

17. Meyer, K.M., Jopp, F., Münkemüller, T., Reuter, H. & Schiffers, K. (2010) Crossing scales in ecology. Special Feature, Basic and Applied Ecology 11, 561-562.

16. Meyer, K.M., Schiffers, K., Münkemüller, T., Schädler, M,.Calabrese, J.M., Basset, A., Breulmann, M., Duquesne, S., Hidding, B,.Huth, A., Schöb, C. & van de Voorde, T.F.J. (2010) Predicting population and community dynamics - the type of aggregation matters. Basic and Applied Ecology 11, 563-571.

15. Meyer, K.M., Wiegand, K. & Ward, D. (2010) Spatially explicit modelling of savanna processes. In: Hill, M.J. & Hanan, M.P. (eds) Ecosystem Function in Savannas: Measurement and Modeling at Landscape to Global Scales. Taylor & Francis.

14. Moustakas, A., Wiegand, K., Meyer, K.M., Ward, D. & Sankaran, M. (2010) Learning new tricks from old trees: revisiting the savanna question. Frontiers of Biogeography 2, 47-53.

13. Meyer, K.M., Vos, M., Mooij, W.M., Hol, W.H.G., Termorshuizen, A.J., Vet, L.E.M. & van der Putten, W.H. (2009) Quantifying the impact of above- and belowground higher trophic levels on plant and herbivore performance by modeling. Oikos 118, 981-990.

12. Meyer, K.M., Mooij, W.M., Vos, M., Hol, W.H.G., van der Putten, W.H. (2009) The power of simulating experiments. Ecological Modelling 220, 2594-2597.

11. Meyer, K.M., Wiegand, K. & Ward, D. (2009) Patch dynamics integrate mechanisms for savanna tree-grass coexistence. Basic and Applied Ecology 10, 491-499.

10. Van der Putten, W.H., Bardgett, R.D., de Ruiter, P.C., Hol, W.H.G., Meyer, K.M., Bezemer, T.M., Bradford, M.A., Christensen, S., Eppinga, M.B., Fukami, T., Hemerik, L., Molofsky, J., Schädler, M., Scherber, C., Strauss, S.Y., Vos, M. & Wardle, D.A. (2009) Empirical and theoretical challenges in aboveground-belowground ecology. Oecologia 161, 1–14.

9. Moustakas, A., Sakkos, K., Wiegand, K., Ward, D., Meyer, K.M. & Eisinger, D. (2009) Are savannas patch-dynamic systems? A landscape model. Ecological Modelling 229, 3576-3588.

8. Meyer, K.M., Ward, D., Wiegand, K. & Moustakas, A. (2008) Multi-proxy evidence for competition between savanna woody species. Perspect. Plant Ecology Evolution and Systematics 10, 63-72.

7. Moustakas, A., Wiegand, K., Getzin, S., Ward, D., Meyer, K.M., Guenther, M. & Mueller, K.-H. (2008) Spacing patterns of an Acacia tree in the Kalahari over a 61-year period: How clumped becomes regular and vice versa. Acta Oecologica 33, 355-364.

6. Meyer, K.M., Wiegand, K., Ward, D. & Moustakas, A. (2007) SATCHMO: A spatial simulation model of growth, competition, and mortality in cycling savanna patches. Ecological Modelling 209, 377-391.

5. Meyer, K.M., Wiegand, K., Ward, D. & Moustakas, A. (2007) The rhythm of savanna patch dynamics. Journal of Ecology 95, 1306-1315.

4. Meyer, K.M., Wiegand, K., Ward, D. & Moustakas, A. (2007) Determining patch size. African Journal of Ecology 46, 440-442.

3. Meyer, K.M., Gimpel, K. & Brandl, R. (2007) Viability analysis of endangered crayfish populations. Journal of Zoology 273, 364-371.

2. Moustakas, A., Guenther, M., Wiegand, K., Mueller, K.-H., Ward, D., Meyer, K.M. & Jeltsch, F. (2006) Long-term mortality patterns of the deep-rooted Acacia erioloba: The middle class shall die! Journal of Vegetation Science 17, 473-480.

1. Meyer, K.M., Ward, D., Moustakas, A. & Wiegand, K. (2005) Big is not better: small Acacia mellifera shrubs are more vital after fire. African Journal of Ecology 43, 131-136.