Habitat suitability of five commonly planted non-native trees in Chile: Implications for an invasion process

Abstract

Non-native tree (NNT) species have been deliberately introduced into new areas. Historically, NNTs were not considered as invasive species, given the benefits they provide, but that has changed during the last decades. The use of non-native trees, whichever purpose they have, should be assessed according to the location and susceptibility of the area to invasion. Forestry trees, such as Pinus and Eucalyptus have been introduced worldwide, being the most planted taxa. Here, we present a complete assessment of the actual invasive stage and potential distribution of most relevant non-native tree species established in the south-Central region of Chile (Pinus radiata, Eucalyptus globulus, Eucalyptus nitens, Pinus contorta and Pseudotsuga menziesii) based on its presences and absences, their global and regional niches, Species Distribution Models (SDM), climatic and anthropogenic variables. None of the studied species maintain the environmental space of their native range. Some of them (P. radiata, E. globulus and E. nitens) have been established under new environmental conditions, thus expanding their niches. Others, such as P. contorta and P. menziesii present a high proportion of stable populations, but there is an even higher proportion of area available for their expansion. Beyond their actual status, all e studied species are capable of expanding their populations into new areas of the studied region. Conservation efforts must be efficiently planned, to reduce these species impacts wherever necessary, but also to avoid their further dispersal into new non-invaded areas.