Landscape and Urban Planning 127 (2014) 154–163 Contents lists available at ScienceDirect Landscape and Urban Planning j o ur na l ho me pag e: www.elsevier.com/locate/landurbplan Research Paper Fine root parameters and mycorrhizal colonization of horse chestnut trees (Aesculus hippocastanum L.) in urban and rural environments Leszek Karli ´ nski a,∗ , Andrzej M. Jagodzi ´ nski a,b , Tomasz Leski a , Paweł Butkiewicz b , Małgorzata Brosz b , Maria Rudawska a a Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland b Pozna´ n University of Life Sciences, Department of Game Management and Forest Protection, Wojska Polskiego 71 C, 60-625 Pozna´ n, Poland h i g h l i g h t s • Urban and rural sites differed in terms of soil characteristics. • Biometry of fine roots was only partly related to the soil variables. • Horse chestnut fine roots were colonized by arbuscular and endophytic fungi. • Trees from urban and rural sites revealed a similar range of arbuscular colonization. a r t i c l e i n f o Article history: Received 27 May 2013 Received in revised form 10 April 2014 Accepted 11 April 2014 Keywords: Fine roots Horse chestnut Mycorrhiza Urban environment a b s t r a c t Horse chestnut trees (Aesculus hippocastanum L.) are stable and important elements of urban and rural landscapes. So far most studies that have investigated horse chestnut trees have observed their above ground characteristics, whereas the roots structure and symbiotic associations with mycorrhizal arbus- cular fungi have been poorly recognized. Therefore, our objective was to perform a detailed study of horse chestnut fine roots and the extent of their colonization by mycorrhizal fungi in urban and rural environments. In the urban area two different study sites were selected: one in the street and the second in city parks. Two rural sites comprised the roadside verges planted with horse chestnut trees in open countryside. The chemical composition of soils revealed significant differences between study sites. The biometric parameters of fine roots are only partly related to soil characteristics. The results revealed a lack of a clear negative effect of the urban environment on fine root parameters, which may suggest a high degree of plasticity in this species in response to heterogeneity of the soil. At all study sites the fine roots of horse chestnut were colonized by arbuscular fungi (AM) and fungal endophytes. Trees from all study sites revealed a similar range of AM colonization. Significant differences were found only between one rural and one urban park site. The results from urban and rural sites revealed horse chestnut as a tree species well adapted to both rural and urban conditions and presented well-established mycorrhizal symbiosis with arbuscular fungi. © 2014 Elsevier B.V. All rights reserved. 1. Introduction Urban and rural ecosystems significantly differ in terms of qualitative and quantitative elements of human pressure. High ∗ Corresponding author. Tel.: +48 61 817 00 33; fax: +48 61 817 01 66. E-mail addresses: leszekk@man.poznan.pl, l.karlinski@interia.pl (L. Karli ´ nski), amj@man.poznan.pl (A.M. Jagodzi ´ nski), tleski@man.poznan.pl (T. Leski), pbutkiewicz.88@o2.pl (P. Butkiewicz), margaretka 16@o2.pl (M. Brosz), mariarud@man.poznan.pl (M. Rudawska). disturbance and fragmentation of an ecosystem, air pollution, the “heat-island effect” or disruption of water relations and nutri- ent cycling are characteristic of urban environments (Bainard, Klironomos, & Gordon, 2011; McDonell & Picket, 1990; Oleksyn, Kloeppel, Lukasiewicz, Karoleski, & Reich, 2007). During the cen- turies, urban soils were modified by remnants of buildings, municipal waste and different materials associated with human activity (Oleksyn et al., 2007; Pickett et al., 2001). This resulted in specific and very heterogenic conditions for tree growth and associ- ated soil microorganisms in urban environments. Rural ecosystems, although generally considered as free of acute environmental http://dx.doi.org/10.1016/j.landurbplan.2014.04.014 0169-2046/© 2014 Elsevier B.V. All rights reserved.