Vegetation and soil differences in ancient opposed to new forests B.J. Graae a,* , P.B. Sunde a , B. Fritzbùger b a Department of Ecology, Biodiversity and Evolution, Botanical Institute, University of Copenhagen, éster Farimagsgade 2D, DK-1353 Copenhagen K, Denmark b Department of Economics and Natural Resources, Royal Veterinary and Agricultural University, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark Received 11 April 2001; received in revised form 27 May 2002; accepted 16 June 2002 Abstract This study compared the vegetation and soils of forest stands with different land-use histories in a major forest complex with new forest stands isolated from ancient forests. Vegetation did not vary signi®cantly in relation to former land-use within the major forest complex, but was signi®cantly different between the major forest complex and the isolated new forests. Plant available phosphate, pH and organic content were not signi®cantly different between stands with different former land-use. There was a negative correlation between the abundance of some forest plant species and distance to ancient forest, even within the small scale of the major forest complex. These results emphasise the slow migration rates of some forest species, even into new forests planted on unimproved soils adjacent to ancient forest. However, this study gives no support to suggestions in the literature that migration rates are slow because of differences in the soils of ancient and new forests. # 2002 Elsevier Science B.V. All rights reserved. Keywords: Vegetation; Soil; Forest continuity; Fragmentation; Colonisation; Migration; Seed dispersal 1. Introduction Various studies from northwestern Europe have demonstrated that the ¯ora of new forests on former agricultural ®elds differs from that of ancient forests (forests which have been forested throughout their recorded history). This difference has usually been attributed to the inability of many forest species to disperse seeds over long distances in agricultural landscapes (Peterken, 1974; Dzwonko and Loster, 1992; Wulf, 1997; Grashof-Bokdam and Geertsema, 1998; Graae, 2000; Graae and Sunde, 2000; Butaye et al., 2001). However, Hermy (1994) and Verheyen and Hermy (2001) noticed that new forests in Belgium often hold dense stands of competitive species, and suggested that soil conditions in these forests may be so altered that competitive species are favoured for decades or centuries. This dense vegetation may deter the establishment of less-competitive species typical of ancient forests. In a recent study, Honnay et al. (1999) found that plant available phosphate concentrations and pH in soils were higher in new forests than those in ancient forests, even after 100 years of forest cover. Petersen (1994) concluded that plant available phosphate did not differ between ancient and new forests in Denmark. He recorded differences in phosphate concentrations in Forest Ecology and Management 177 (2003) 179±190 * Corresponding author. Present address: Bente Jessen Graae, Arctic Station, 3953 Qeqertarsuaq, Greenland. Tel.: 299-92-1384; fax: 299-92-1385. E-mail address: bentej@bot.ku.dk (B.J. Graae). 0378-1127/02/$ ± see front matter # 2002 Elsevier Science B.V. All rights reserved. PII:S0378-1127(02)00438-3