The Ecological Potential of Wild Orchids for in situ and ex situ Conservation of Rare Species in Enrekang, South Sulawesi, Indonesia

Abstract

The purpose of this study is to evaluate the ecological potential of Sulawesi wild orchids in their natural habitat as a basis for their in situ and ex situ conservation. A field survey was conducted from July to August, 2010 in the Bolli Forest in Enrekang, South Sulawesi. Purposive sampling method based on land forms, such as riparian, dry-plate and the slope zones was used to collect data on orchids in the field. Results showed that 37 species of orchids were mostly found in riparian zones, 36 of which species were mostly epiphytes attached to the first branching of host trees (39.4%) compared to 28.9% on the main tree trunk. The tree species associated with 10 or more species of orchids were Eugenia sp.1, Vitex cofassus and Myristica inners. Ecological studies indicated that on the riparian zone, there were only 4 out of 24 species of orchids have Important Value (IV) of 10%, namely: Phalaenopsis ambonensis, Pholidota imbricata, Eria pubescens and Liparis condylobulbon. In the dry-plate zone, there were only 6 out of the 22 orchid’s species have IV above 10%, i.e.: Bulbophyllum laxiflorum, Phalaenopsis ambonensis, Pholidota imbricata, Eria pubescens, Cymbidium finlaysonianum and Phalaenopsis amabilis. In the slope zone, only 7 of the 12 orchids species have IV of above 10 i.e. Dendrobium teretifolia, Aerides jarkianum, Pholidota imbricata, Phalaenopsi. amabilis, Eria pubescens, Dendrobium cruminatum, and Bulbophylum laxiflorum. The highest diversity index was found in dry-plate zone (2.55), followed by riparian zone (2.14), and slope zone (2.05), while the highest similarity index was found in the riparian-dry plate (50.16%) followed by riparian-slope (39.14%) and slope-dry plate zone (37.46%). There were several types of orchids that are found growing only in one zone with a low relative density and a narrow distribution of species, such as Phalaenopsis amabilis and Dendrobium anosmum var. Huttoni. The latter have large fragrant flowers and attractive colors. Both species are frequently hunted by the local forest communities. The natural population of orchid species is diminishing as a result of poaching, will be susceptible to local extinction if their habitat is disturbed, demanding the attention of those concerned for their much needed in situ and ex situ conservation.