Landscape and Urban Planning 120 (2013) 107–118 Contents lists available at ScienceDirect Landscape and Urban Planning jou rn al hom ep age: www.elsevier.com/locate/landurbplan Research paper Using high-resolution remote sensing data for habitat suitability models of Bromeliaceae in the city of Mérida, Venezuela Caroline Judith a,b,∗ , Julio V. Schneider a,b,c , Marco Schmidt a,b,c , Rengifo Ortega d , Juan Gaviria e,f , Georg Zizka a,b,c a Senckenberg Research Institute and Natural History Museum Frankfurt, Department of Botany and Molecular Evolution, Senckenberganlage 25, 60325 Frankfurt am Main, Germany b Goethe-University, Institute of Ecology, Evolution and Diversity, Max-von-Laue-Str. 13, 60439 Frankfurt am Main, Germany c Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325 Frankfurt am Main, Germany d Geomatikk AS, Oslo Section, Postbox 103, Økern, Norway e Instituto Jardín Botánico, Facultad de Ciencias, Núcleo La Hechicera, Universidad de los Andes, Apartado 52, 5212 Mérida, Venezuela f GeoBio-Center LMU, Ludwig-Maximilians-University München, Richard-Wagner-Str. 10, 80333 München, Germany h i g h l i g h t s • Twenty species and four genera of Bromeliaceae were found in the city of Mérida. • Bromeliaceae differ in their ecological preferences, with CAM species being adapted to sealed areas. • Combining satellite and elevation data is suitable for bromeliad distribution models. a r t i c l e i n f o Article history: Received 24 October 2012 Received in revised form 26 April 2013 Accepted 19 August 2013 Keywords: Andes Bromeliaceae Habitat suitability modelling Satellite imagery Tillandsia Urban biodiversity a b s t r a c t Little information is available concerning the effects of the increasing urbanization on biodiversity in tropical regions. Species distribution modelling based on interpolated climate data is a widely applied, time- and cost-effective tool to estimate the potential species richness in a target area. However, high fragmentation, strong environmental gradients on a small-scale, and lack of fine-scale environmental data in tropical urban areas require alternative approaches. In this study we combined a rapid species assess- ment approach with environmental niche modelling based on high-resolution ASTER satellite imagery to predict species distributions of Bromeliaceae in the city of Mérida, Venezuela. Twenty species of Bromeli- aceae, e.g. 36% of the total bromeliad diversity of the state of Mérida, were observed in the city, including seven species with CAM physiology. CAM species showed significantly higher occurrence probabilities in zones with higher soil sealing, whereas in C3 species a trend across soilsealing zones was not observed. The remarkable urban species richness of Bromeliaceae is here attributed to the species’ different adap- tive strategies, as well as to the strong elevation gradient of Mérida city. Our species modelling approach provides new possibilities for the identification of indicator species in different urban built-up areas. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Urbanization continues to increase on a global scale and individual cities are attaining unprecedented sizes. Nowadays, more than 50% of the world’s population lives in urban areas ∗ Corresponding author at: Goethe-University, Institute of Ecology, Evolution and Diversity, Max-von-Laue-Str. 13, 60439 Frankfurt am Main, Germany. Tel.: +49 069 798 42226. E-mail addresses: caroline.judith@ymail.com (C. Judith), Julio.Schneider@senckenberg.de (J.V. Schneider), Marco.Schmidt@senckenberg.de (M. Schmidt), rengifo.ortega@geomatikk.no (R. Ortega), gaviria@ula.de (J. Gaviria), Georg.Zizka@senckenberg.de (G. Zizka). (United Nations, 2010). This trend imposes severe pressure upon the biodiversity in urban areas, making biodiversity research in populated areas a major concern. For historical reasons, most eco- logical and biodiversity assessments in urban areas have been conducted in industrialized countries of the northern hemisphere, whereas few studies are known from tropical or subtropical major cities (e.g. Franceschi, 1996; Sattler, Schmidt, & da Silva Alves, 2010), many of which are among the fastest growing ones world- wide (Cohen, 2006). Urbanization is accompanied by a multitude of effects on the local species composition, such as habitat loss, fragmentation, iso- lation, and alteration. Generally, urban areas are characterized by highly fragmented green areas with different levels of connectivity 0169-2046/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.landurbplan.2013.08.012