Christer Björkman

My research has mainly been in two study systems:

Forest insects, particularly the European pine sawfly (Neodiprion sertifer).

It is anticipated that insect outbreaks may become more frequent and severe in the future as a consequence of the ongoing global change. However, our knowledge about the mechanisms triggering the outbreaks forest and other insects are still not very well known. We study how (i) environmental heterogeneity and (ii) multiple stressors (moose browsing + insect herbivory) affect pine trees and ecological interactions. 

Insects on willows, mainly leaf beetles (Phratora vulgatissima) and predatory omnivorous  bugs (Miridae and Anthocoridae).

Willows are grown as a renewable source of energy and leaf beetles are the most severe pests. Willow growth is reduced by 40% when heavily defoliated. Insecticides is not an option and  there is a need to control the beetles via resistant plants and biological control. Indirect plant resistance, acting via the natural enemies, is an important aspect in our studies. We also conduct long-term studies of the population dynamics of leaf beetles and their natural enemies in planted and natural willow stands.

As I am about to soon retire, I have decided to not have any research projects other than ones where I have a secondary role.

Research themes

Forest management to mitigate the risk for insect damage

Population dynamics of insect herbivores and their natural enemies

Plant resistance: Protecting conifer seedlings against insects

Role of insect herbivores and ecological interactions in the spread of vector-borne diseases

ORCID

SUPERVISION

Doktorander

Fredrika Wrethling (2020- , co-supervisor)
Kristina Berggren Nieto (PhD, 2024)
Dragos Cocos (PhD, 2023, co-supervisor)
Yayuan Chen (PhD, 2021)
Michelle Nordkvist (PhD, 2020)
Davide Bellone (PhD, 2018)
Kim Karlsson Moritz (PhD, 2017, co-supervisor)
Jörg Stephan (PhD, 2015) 
Anna-Sara Liman (PhD, 2015)
Ida Kollberg (PhD, 2013)
Freddy Miranda (PhD, 2011)
Peter Dalin (PhD, 2004)
Lisette Lenoir (PhD, 2001, co-supervisor)
Agnis Smits (PhD, 2001, co-supervisor)
Weronika Linkowski (Fil. Lic., 2000, co-supervisor)

Post Docs

Xiaoning ('Nina') Zhang (2020 – 2023) Award from His Majesty Carl XVI Gustaf's science fund
Adriana Puentes (2014 – 2017) Award from His Majesty Carl XVI Gustaf's science fund
Tea Ammunét (2011 – 2014)
Mikaela Torp (2010 – 2013)
Maartje Klapwijk (2009 – 2012) Award from His Majesty Carl XVI Gustaf's science fund
Anna Lehrman (2008 – 2010)
Johan Stenberg (2008 – 2010) Award from His Majesty Carl XVI Gustaf's science fund
Enric Vila (2006 – 2007)
Gaétan Moreau (2006)

Master's students

Agnès Brosset (2017)
Sabine Barets (2016)
Carin Eriksson (2010)
Hans Johansson (2009) Hampus von Posts Prize for best Master’s thesis
Lina Grönberg (2007) Hampus von Posts Prize for best Master’s thesis
Linda Larsson (2007) Hampus von Posts Prize for best Master’s thesis
Alban Maisonnasse (2006)
Nina Fries (2006, co-supervisor)
Karin Ahrné (2002)
Anna-Sara Liman (2002)
Peter Dalin (1999)
Benita Bengtsson (1997)
Georg Nygren (1997)
Peter Zonneveld (1997)

Connecting the dots: Managing species interaction networks to mitigate the impacts of global change
Abdala-Roberts, L, Puentes, A, Finke, DL, Marquis, RJ, Montserrat, M, Poelman, EH,Rasmann, S, Sentis, S, Symons, CC, vam Dam, NM, Wimp, G, Björkman, C & Mooney, KA
ELIFE DOI10.7554/eLife.98899

Island biogeography theory and the assembly patterns of native versus non-native forest insects
Mech, AM, Liebhold, AM, Trombik, J, Björkman, C, Gandhi, KJK, Lyytikäinen-Saarenmaa, P, Pureswaran, DS, Synek, J, Klapwijk, MJ (2024)
OIKOS, 20024: e10768

Healing of bark wounds in Norway spruce seedlings: Effects of methyl jasmonate treatment on a plant tolerance trait
Chen, Y, Björkman, C, Bylund, H, Björklund, N, Högberg, K-A, Puentes, A (2023) Trees, 37: 1369-1384

Synergistic effects of methyl jasmonate treatment and propagation method on Norway spruce resistance against a bark-feeding insect
Berggren, K, Nordkvist, M, Björkman, C, Bylund, H, Klapwijk, M, Puentes A (2023) Frontiers in Plant Science, DOI 10.3389/fpls.2023.1165156

The relationship between moose browsing, habitat structure and predation pressure on insect herbivores 
Nordkvist, M, Klapwijk, MJ, Barets, S, Björkman, C (2022)
Basic and Applied Ecology, 66: 1-10.

When is it biological control? A framework of definitions, mechanisms, and classifications
Stenberg JA, Sundh I, Becher PG, Björkman C, Dubey M, Egan PA, Friberg H, Gil JF, Jensen DF, Jonsson M, Karlsson M, Khalil S, Ninkovic V, Rehermann G, Vetukuri, RR & Viketoft M (2021) 
Journal of Pest Science, 94: 665-676.

Interacting effects of insect and ungulate herbivory on Scots pine growth
Nordkvist M, Klapwijk MJ, Edenius LR & Björkman, C (2020)
Scientific Reports, 10: 22341.

Complex responses of global insect pests to climate warming
Lehmann P, Ammunét T, Barton M, Battisti A, Eigenbrode SD, Jepsen JU, Kalinkat G, Neuvonen S, Niemelä P, Økland B, Terblanche JS & Björkman C (2020)
Frontiers in Ecology and the Environment, 18: 141-150. 

Tri‐trophic interactions: bridging species, communities and ecosystems
Abdala‐Roberts L, Puentes A, Finke DL, Marquis RJ, Montserrat M, Poelman EH, Rasmann S, Sentis A, van Dam NM, Wimp G, Mooney K & Björkman C  (2019)       Ecology Letters, doi.org/10.1111/ele.13392

Trait‐mediated indirect interactions: Moose browsing increases sawfly fecundity through plant‐induced responses
Nordkvist M, Klapwijk M, Edenius L, Gershenzon J, Schmidt A & Björkman C  (2019) Ecology and Evolution, DOI: 10.1002/ece3.5581
"Insects get boost from pines chewed by moose" (Dispatch Front Ecol Environm doi:10.1002/fee.2103)

Capturing complexity: Forests, decision-making and climate change mitigation action
Klapwijk MJ, Boberg J, Bergh J, Bishop K, Björkman C, Ellison D, Felton A, Lidskog R, Lundmark T, Keskitalo ECH, Sonesson J, Nordin A, Nordström E-M, Stenlid J & Mårald E  (2018) Global Environmental Change, 52: 238-247.

Enhanced leaf nitrogen status stabilizes omnivore population density
Liman A-S, Dalin P & Björkman C  (2017) Oecologia, 183: 57-65.

Forest restoration as a double-edged sword: the conflict between biodversity conservation and pest control
Kärvemo S, Björkman C, Johansson T, Weslien J & Hjältén J  (2017) Journal of Applied Ecology, doi: 10.1111/1365-2664.12905.

Forest management and biocontrol of insect pests
Klapwijk MJ, Bylund H, Schroeder M & Björkman C  (2016) Forestry, doi:10.1093/forestry/cpw019.

Replacing monocultures with mixed-species stands: Ecosystem service implications of two production forest alternatives in Sweden
Felton A, Nilsson U, Sonesson J, Felton A, Roberge J-M, Ranius T, Ahlström M, Bergh J, Björkman C, Boberg J, Drössler L, Fahlvik N, Gong P, Holmström E, Keskitalo CH, Klapwijk MJ, Laudon H, Lundmark T, Niklasson M, Nordin A, Pettersson M, Stenlid J, Sténs A & Wallertz K  (2016) Ambio 45(Suppl. 2): S124-139.

How far away is the next basket of eggs? Spatial memory and perceived cues shape aggregation patterns in a leaf beetle
Stephan J, Stenberg JA & Björkman C  (2015) Ecology 96: 908-914.

Climate Change and Insect Pests
Björkman C & Niemelä P (eds)  (2015)  CABI Climate Change Series 8

Optimizing crops for biocontrol of pests and disease
Stenberg JA, Heil M, Åhman I & Björkman C  (2015) Trends in Plant Science, doi: 10.1016/j.tplants.2015.08.007.

Temperature affects insect outbreak risk through tritrophic interactions mediated by plant secondarycompounds
Kollberg I, Bylund H, Jonsson T, Schmidt A, Gershenzon J & Björkman C  (2015)  Ecosphere 6(6):102.http://dx.doi.org/10.1890/ES15-000021.1

Forest insects and climate change: long-term trends in herbivore damage
Klapwijk MJ, Csóka G, Hirka A & Björkman C  (2013) Ecology and Evolution doi: 10.1002/ece3.717 [PDF]

CV and List of publications (not fully updated)