The relevancy and perspectives of scientific flora projects: two examples from the Flora of Thailand project
Henrik Ærenlund Pedersen
Associate Professor, Ph.D., Botanical Garden & Museum, Natural History Museum of Denmark, University of Copenhagen
Is it really worthwhile revising the same flora repeatedly? A case study in Thai Orchidaceae. – In many contexts, scientific floras (dealing with one, several or all plant families on a national or regional scale) are the most intensively used surveys and identification tools for species of vascular plants. Flora of Thailand will be the first real standard flora to cover all families of flowering plants in Thailand. Nevertheless, the Thai representatives of a number of plant groups have undergone one or more revisions previously. Is it worthwhile revising such groups again for Flora of Thailand – and would it even make sense to start thinking of a second edition of the flora? To throw some light on this, I compared three successive revisions of the orchid subfamily Orchidoideae in Thailand (published in 1958–1964, 1977–1978 and 2011, respectively). Together, the three revisions exhibited a progressive increase in the net number of accepted taxa. The relative increase was highest from the first to the second revision, but still substantial from the second to the third. The net results covered an even higher number of changes (additions end exclusions of taxa) that partly neutralized each other – and other changes were in themselves neutral in relation to the net number of taxa accepted. Classification at species level, but not at genus level, tended to stabilize over time. Altogether, the results demonstrate that both the second and the third revision were worthwhile indeed, as each of them provided comprehensive changes (arguably improvements) compared to the latest previous revision.
Flora projects as drivers of biodiversity research, exemplified by the treatment of the Orchidaceae for Flora of Thailand. – Any scientific flora project relies primarily on a taxonomic revision of the flora accommodated in the region covered by that project. Furthermore, it is commonly recognized that once the flora handbook has been published, it represents a major source of knowledge and data that can be utilized in other research fields such as biogeography, vegetation ecology and macro-ecology. On the other hand, surprisingly little attention has been given to the fact that flora projects can to a wide extent initiate and facilitate complementary research activities during their own lifetime. Using the ongoing treatment of the Orchidaceae for Flora of Thailand as an example, it is demonstrated how the organization of field trips and the establishment of research groups within the framework of the flora project – together with the recurrent need for achieving taxonomic clarity beyond the borders of Thailand – have given rise to complementary research on multiple aspects of orchid-related biodiversity. Examples include: the preparation of global monographs; traditional or morphometrically based revisions of intricate species complexes throughout mainland Asia; minor biogeographic studies and autecological studies of epiphytic as well as terrestrial species. Additionally, it is demonstrated how the efforts of making existing data available for the flora project (e.g. through the Seidenfaden Database of Orchids and the Native Thai Orchid Network) may highly benefit non-floristic research as well.
