Both spatiotemporal connectivity and habitat quality limit the immigration of forest plants into wooded corridors
Extensive afforestation of agricultural areas has increased the importance of green corridors as a dispersal network. We tested the effect of spatiotemporal connectivity, edge effect and habitat structural quality of wooded corridors on the long-term immigration success of forest specialist plants relative to the performance of forest generalists. In agricultural landscapes of central and southern Estonia, we sampled 28 historically connected and 52 isolated tree lines and alleys with a minimum age of 50 years, and 93 edges of ancient forests. The regional pool of common forest plants was compiled using species’ frequency data in 91 ancient forests. Both landscape connectivity and habitat quality affected the richness of response groups, but specialists and generalists responded to different drivers. Forest specialists required long-term neighbourhoods of ancient forest and benefited from a direct connection between forest and corridor. Habitat generalists reacted positively to the recently modified structure of the landscape. When a corridor was connected to forest, the dual edge in the corridor did not result in an increased negative edge effect on forest specialist arrival. Even if both specialists and generalists required wide corridors with optimum shade, forest specialists also benefited from mature overstorey and outward overhanging branches, whereas forest generalists used disturbance-created microhabitats. We conclude that only wooded corridors with long-term connectivity to seed source forests and widely branched tree canopies will function as a green infrastructure supporting forest-specific biodiversity.
KeywordsAncient forest species Forest plant dispersal Historical ecology Landscape planning Patch-corridor-matrix system Spatiotemporal ecology
This project was supported by the Estonian Science Agency (project no. 7878, IUT 20-31 and IUT 34-7), the ERA-Net BiodivERsA project smallFOREST and the European Union through the European Regional Development Fund (the Centre of Excellence Ecolchange). We are grateful to Robert Szava-Kovats for comments and language editing. We also thank Thomas Abeli and two anonymous reviewers for their helpful comments.
Compliance with ethical standards
Conflict of interest
The authors declare no conflict of interest.
- Aunap R (2011) Eesti Atlas, 4th edn. Avita, TallinnGoogle Scholar
- Fox J, Weisberg S (2011) An R companion to applied regression, 2nd edn. Sage, Thousand OaksGoogle Scholar
- Leht M (2010) Eesti Taimede Määraja, 3rd edn. Eesti Loodusfoto, TartuGoogle Scholar
- Lõhmus E (2004) Eesti metsakasvukohatüübid, 2nd edn. Eesti Loodusfoto, TartuGoogle Scholar
- MacDonald MA (2003) The role of corridors in biodiversity conservation in production forest landscapes: a literature review. Tasforests 14:41–52Google Scholar
- Oksanen J, Blanchet FG, Kindt R et al (2013) vegan: Community Ecology PackageGoogle Scholar
- QGIS Development Team (2015) QGIS Geographic Information System. Open Source Geospatial FoundationGoogle Scholar
- R Core Team (2016) R: a language and environment for statistical computing. R Foundation for Statistical Computing, ViennaGoogle Scholar
- Schmidt M, Kriebitzsch W-U, Ewald J (2011) Waldartenlisten der Farn- und Blütenpflanzen. Moose und Flechten Deutschlands, Bundesamt für Naturschutz, BonnGoogle Scholar