Using biodiversity databases to verify and improve descriptions of tree species climatic requirements

• Data on natural and introduced tree distributions are now available online.
• Interpolated climatic data allow these data to be analysed.
• Species climatic requirements can be assessed and suitable areas mapped.
• Two Australian eucalypt species are used here to illustrate the methods.
• But the methods described could be used with any tree species anywhere.

Understanding tree species climatic adaptability, as well as climatic conditions within their natural distributions, is crucial for managing forests for both commercial and conservation objectives under climate change. Multi-million dollar investments in biodiversity databases are providing forestry professionals with freely accessible tools to carry out these kinds of analyses for many tree species. The climatic requirements of hundreds of tree species have been described in the commercially available Forestry Compendium developed by CAB International, but these descriptions have often relied on expert opinion where information is lacking. It is desirable that descriptions of tree species climatic requirements should, as far as possible, be explicit, quantitative and based on specific observations. This paper describes how the Atlas of Living Australia (ALA) and the Global Biodiversity Information Facility (GBIF) can provide specific observations to assist verifying and, where necessary, improving descriptions of tree species climatic requirements. It focuses mainly on Australian species as the ALA is one of the most sophisticated biodiversity databases currently available for a single country. However, the ALA also has international relevance as Australian eucalypts and acacias are important plantation species in many countries. Data in the GBIF complement the ALA data by providing very useful information on where Australian tree species are growing outside Australia. Analyses of a commercially important species (Eucalyptus nitens) and a lesser-known species (E. botryoides) demonstrate how descriptions of climatic requirements can be verified and, if necessary, improved. However, the general methods described have the potential to be applied to many tree species. Some of the advantages and disadvantages of these systems are discussed and possible improvements are suggested.