LANKESTERIANA 17(1): 17-47. 2017. doi: http://dx.doi.org/10.15517/lank.v17i1.27999 ORCHID DISTRIBUTION AND BIOCLIMATIC NICHES AS A STRATEGY TO CLIMATE CHANGE IN AREAS OF TROPICAL DRY FOREST IN COLOMBIA GUILLERMO A. REINA-RODRÍGUEZ1,3, JORGE E. RUBIANO MEJÍA2, FABIO A. CASTRO LLANOS2 & IGNASI SORIANO1 1 Department of Evolutionary Biology, Ecology and Environmental Sciences., University of Barcelona, Section of Botany and Mycology. Av. Diagonal 643. E-08028 Barcelona, Spain. C.P. 08028 2 Department of Geography, Valle University, Cali, Colombia. Av. Pasoancho 100-00, Cali, Colombia. 3 Author for correspondence:
[email protected] ABSTRACT. Climate change projections in Colombia predict an average increase in temperature of 2.6°C and in precipitation of 20% by the end of the century. These changes would directly affect the tropical dry forest (TDF) and its biodiversity. Epiphytic orchids, more exposed to the atmosphere than the terrestrial biota, remain dependent on climatic variables, making them particularly susceptible to climate change. We studied the spatial and temporal changes of a focal group of 12 orchid species typical of the TDF in Colombia, and the future conservation areas to this ecosystem. The algorithm used by MaxEnt was employed for modelling. A total of 439 records: direct observations (276); herbaria collections (159) and bibliographical sources (4) collected since September 2009 to April 2015 were considered for use in training the model. The actual potential niche was compared to the SRES 8.5 climate change emissions scenario for two periods: 2020–2049 (2030) and 2040–2069 (2050). The results indicate an altitudinal displacement compared to the present, conditioned by variables such as temperature, accessibility and precipitation.