ORIGINAL ARTICLE Key factors in organization of sandy orthopteran assemblages Zoltán Kenyeres 1 & Szilárd Szabó 2 & Csaba Szinetár 3 & Gábor Takács 4 & Norbert Bauer 5 Received: 12 August 2018 /Accepted: 12 February 2019 # Institute of Zoology, Slovak Academy of Sciences 2019 Abstract Orthopterans are important functional elements of ecosystems, in which several factors influence their distribution and density. Factors related to the vegetation, macro- and microclimate have been intensively investigated, although the role of the bedrock and soil in organization of orthopteran assemblages has not been explored sufficiently. Our results showed that general effects, as (1) dry, warm macro- and microclimate, (2) short vegetation, (3) presence of about 30% bare sand surface, are important habitat factors organizing sandy orthopteran assemblages of the Carpathian Basin too. Further we found that optimal climate and vegetation structure is not sufficient for a high species number of sand-specialists. Local assemblages rich in sand elements are related to sand areas characterised by a proportion of the fine fraction of the soil (= small-fine-dust fractions together) of around 80%. Keywords Grasshoppers . Climate . Soil parameters . Biogeography . Aridity . Insolation Introduction Orthopterans are important functional elements of ecosystems (Crous et al. 2014). Focusing on the taxon is also facilitated by the fact that the main aspects of its assemblages are the same when compared around the globe (Lockwood et al. 1994; Kenyeres et al. 2014). Various factors (vegetation structure, microclimate, food preference, land use, oviposition possibil- ities, predation, and competition) influence the distribution and number of orthopteran species (Fielding and Brusven 1993; Báldi and Kisbenedek 1999). The impact of these fac- tors is not uniformly known. The background factors related to the vegetation have been intensively investigated (Samways 1997; Gardiner et al. 2002; Bazelet and Samways 2011; Weiss et al. 2013), while the role of the bedrock and soil (Johnson 1989; Crous et al. 2014) has not been explored suf- ficiently. Furthermore, most of the studies on the role of the bedrock and soil do not approach the issue from the perspec- tive of assemblages, but of species (Meats 1970; Sharma 1984; Herrmann et al. 2010; Fielding 2011). The specific physical structure of soils formed on sand bedrock has long been recognized, and the phrases Bsand- specialist^ or Bsand-dwelling^ have long been used to charac- terize the habitat preferences of plant and animal species (Holm 1892; Spalding 1909). The specific role in shaping the flora and vegetation of sand areas was also described long ago (Kerner 1863). The background of this phenomenon is the effects of the water balance and soil conditions which enhance extremities (Fekete 1992; Bartha et al. 2008). The arthropod communities of sand grasslands are also unique. A sand spe- cialist character is evident for species laying their eggs in the ground, for which sand bedrock and soil is really suitable (Woodman 2017). In addition, the strong link to habitats char- acterized by open sandy areas, through energy processes and climatic demand, is quite strong for other taxa, too (Desender and Bosmans 1998). The latter phenomenon has been most studied on beetles (Ljungberg 2002; Cornelisse and Hafernik 2009; Ödman et al. 2011; Cizek et al. 2012; Olsson et al. 2014), but a preference for sand is also well-known for spiders (Horváth et al. 2013), ants (Bonte et al. 2003), butterflies (Metzler 2014), antlion and wormlion larvae (Devetak and * Zoltán Kenyeres kenyeres@acridabt.hu 1 Acrida Conservational Research L.P, Deák F. u. 7, Tapolca 8300, Hungary 2 Department of Physical Geography and Geoinformatics, University of Debrecen, Egyetem tér 1, Debrecen 4032, Hungary 3 Department of Zoology, Savaria Centre, Eötvös Loránd University, Károlyi Gáspár tér 4, Szombathely 9700, Hungary 4 Fertő-Hanság National Park Directorate, Rév-Kócsagvár, Sarród 9435, Hungary 5 Department of Botany, Hungarian Natural History Museum, Könyves K. krt. 40, Budapest 1087, Hungary Biologia https://doi.org/10.2478/s11756-019-00217-y