Present address and correspondence. Alterra, Centre for Ecosystem Studies, Droevendaalsesteeg 3, PO Box 47, 6700 AA, Wageningen, the Netherlands. E-mail: David.Kleijn@wur.nl.
In search for key biogeochemical factors affecting plant species persistence in heathland and acidic grasslands: a comparison of common and rare species
Article first published online: 17 DEC 2007
© 2007 The Authors. Journal compilation © 2007 British Ecological Society
Journal of Applied Ecology
Volume 45, Issue 2, pages 680–687, April 2008
How to Cite
Kleijn, D., Bekker, R. M., Bobbink, R., De Graaf, M. C. C. and Roelofs, J. G. M. (2008), In search for key biogeochemical factors affecting plant species persistence in heathland and acidic grasslands: a comparison of common and rare species. Journal of Applied Ecology, 45: 680–687. doi: 10.1111/j.1365-2664.2007.01444.x
- Issue published online: 17 DEC 2007
- Article first published online: 17 DEC 2007
- Received 24 November 2006; accepted 6 November 2007 Handling Editor: Robert Freckleton
- atmospheric deposition;
- ecological amplitude;
- plant species conservation;
- Red Data Book species
- 1During the last century, many plant species typical of heathland and nutrient-poor acidic grasslands have become rare whereas others have remained common. Habitat restoration often fails to enhance the rare species, which may in part be caused by the failure to restore the biogeochemical conditions suited to these species. Many soil variables have been shown to affect plant fitness but it is unknown what their relative importance is and whether any biogeochemical variable acts as a key factor constraining the persistence of rare heathland species.
- 2We compiled a data set consisting of 300 vegetation samples and the associated soil chemical properties from a range of studies carried out across the Netherlands. We asked whether growth sites of rare and common species typical of heathland and acidic grasslands differed in their biogeochemical properties, and whether growth sites of rare species displayed less variation in soil biogeochemical variables (e.g. had narrower ecological amplitude).
- 3Regardless of rarity, the species’ growth sites were most accurately described by a curvilinear relationship between pH and Al/Ca ratios. Other soil characteristics did not vary systematically with changing acidity of the soil or the patterns were less pronounced. Acidification will therefore most rapidly and predictably result in an increase in Al/Ca ratio whereas this is not necessarily the case for the other soil variables affecting plant fitness.
- 4The soil ammonium (NH4) concentration and ammonium/nitrate (NH4/NO3) ratio were 3·5 and 3 times higher, respectively, in growth sites of common species compared with those of rare species. No other measured variable differed significantly between rare and common plant species.
- 5On average rare species had a significantly narrower ecological amplitude than common species for soil biogeochemical parameters.
- 6Synthesis and applications. A greater sensitivity to high NH4 concentrations in combination with a narrower ecological tolerance zone for a range of soil biogeochemical factors may explain the demise of rare species adapted to nutrient-poor acidic habitats in recent decades. Conservation management should aim to restore low NH4 concentrations and NH4/NO3 ratios. Experimental studies indicate that the most effective way to do this is through removal of the topsoil in combination with liming.