An assessment of potential responses of Melaleuca genus to global climate change

The genus Melaleuca consists of around 260 species covering over eight million hectares (including native and introduced species) and distributed mostly in Australia, but also occurring in South-East Asia, the Southern United States and the Caribbean. Melaleuca populations predominantly occur in wetland or/and coastal ecosystems where they have been significantly affected by climate change. This paper assesses the potential responses of the Melaleuca genus to climate change, based on the synthesis of worldwide published data. The main findings include: (i) that the Melaleuca genus has a rich species diversity, and significant phenotypic diversity in a variety of ecosystems; (ii) they demonstrate significant local adaptation to harsh conditions; and (iii) the fossil records and taxon biology indicate the evolution of the Melaleuca genus began around 38 million years ago and they have survived several significant climatic alterations, particularly a shift towards cooler and drier climates that has occurred over this period. These findings show that the Melaleuca genus is highly resilient and adaptable and based on this, this paper argues that Melaleuca can adapt to climate change through Wright’s ‘migrational adaptation’, and can be managed to achieve sustainable benefits.