Community Ecology

, Volume 18, Issue 1, pp 1–10 | Cite as

Network analysis of phenological units to detect important species in plant-pollinator assemblages: can it inform conservation strategies?

  • P. BiellaEmail author
  • J. Ollerton
  • M. Barcella
  • S. Assini


Conservation of species is often focused either only on those that are endangered, or on maximising the number recorded on species lists. However, species share space and time with others, thus interacting and building frameworks of relationships that can be unravelled by community-level network analysis. It is these relationships that ultimately drive ecosystem function via the transfer of energy and nutrients. However interactions are rarely considered in conservation planning. Network analysis can be used to detect key species (“hubs”) that play an important role in cohesiveness of networks. We applied this approach to plant-pollinator communities on two montane Northern Apennine grasslands, paying special attention to the modules and the identity of hubs. We performed season-wide sampling and then focused the network analyses on time units consistent with plant phenology. After testing for significance of modules, only some modules were found to be significantly segregated from others. Thus, networks were organized around a structured core of modules with a set of companion species that were not organized into compartments. Using a network approach we obtained a list of important plant and pollinator species, including three Network Hubs of utmost importance, and other hubs of particular biogeographical interest. By having a lot of links and high partner diversity, hubs should convey stability to networks. Due to their role in the networks, taking into account such key species when considering the management of sites could help to preserve the greatest number of interactions and thus support many other species.


Community analysis Connectance Ecological network Grassland Habitat management Hub Modularity Nestedness Phenology Pollination 





Principal Component Analysis


The Plant List (2013) for plants Seifert (2004) for Hymenoptera: Formicidae and de Jong et al. (2014) for other insects 


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© Akadémiai Kiadó, Budapest 2017

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Authors and Affiliations

  • P. Biella
    • 1
    • 2
    • 4
    Email author
  • J. Ollerton
    • 3
  • M. Barcella
    • 4
  • S. Assini
    • 4
  1. 1.Department of Zoology, Faculty of ScienceUniversity of South BohemiaČeské BudějoviceCzech Republic
  2. 2.Institute of EntomologyBiology Centre of the Academy of Sciences of the Czech Republic v.v.i.České BudějoviceCzech Republic
  3. 3.Faculty of Arts, Science and TechnologyUniversity of NorthamptonNorthamptonUK
  4. 4.Department of Earth and Environment Sciences (sect. Landscape Ecology)University of PaviaPaviaItaly

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