LANKESTERIANA 19(2): 107–124. 2019. doi: http://dx.doi.org/10.15517/lank.v19i2.38775 ORCHID DIVERSITY IN ANTHROPOGENIC-INDUCED DEGRADED TROPICAL RAINFOREST, AN EXTRAPOLATION TOWARDS CONSERVATION EDWARD E. BESI, DOME NIKONG, MUSKHAZLI MUSTAFA & RUSEA GO* Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan, Malaysia *Corresponding author: [email protected] ABSTRACT. The uncontrolled logging in Peninsular Malaysia and the resulting mudslides in the lowland areas have been perilous, not to just humans, but also to another biodiversity, including the wild orchids. Their survival in these highly depleted areas is being overlooked due to the inaccessible and harsh environment. This paper reports on the rescue of orchids at risk from the disturbed forests for ex-situ conservation, the identification of the diversity of orchids and the evaluation of the influence of micro-climatic changes induced by clear-cut logging towards the resilience of orchids in the flood-disturbed secondary forests and logged forests in Terengganu and Kelantan, located at the central region of Peninsular Malaysia, where the forest destruction by logging activities has been extensive. 109 orchid species belonging to 40 genera were collected from the disturbed areas. The diversity and data analyses show that the disturbed secondary forests had a higher orchid density (0.0133 plants/ m2) than the logged sites (0.0040 plants/m2) as the habitat conditions were more dependable. Nevertheless, the logged forests harboured a higher diversity of orchids (H=4.50 and D=0.99) of which 97.9% were epiphytes. Eleven rare species were found along with six species endemic to Peninsular Malaysia, with two species new to science. The results highlighted the factors that allow the orchids to flourish or suffer in the disturbed forests. The logged forests had a higher ambient temperature and lower moisture level than the mud flood-disturbed and canopy-covered secondary forests. Apart from the extensive ground vegetation due to logs dragging extraction, low soil moisture and absence of leaf litter were believed to be the major attributes causing the low abundance of terrestrial orchids. The high abundance and diversity of epiphytic orchids and the large difference of their densities between the logged sites were influenced by the densities of fallen trees hosting orchid(s), disturbance- induced dryness stresses, durations of exposure to the anthropogenic-induced disturbance, and less favourable soil conditions for the terrestrial orchids. KEY WORDS: conservation, diversity, dryness stress, ecology, epiphyte, logged forest, mudslides, Orchidaceae Introduction. Kuala Koh, Kelantan and Tasek Kenyir, and Bateq (Kuala Koh, Kelantan). The tribal people Terengganu are the largest and commonly visited parts forage the forest for food and medicines apart from of the Peninsular Malaysia’s National Park. Both are hunting and fishing for their daily necessities (Ramle located in the northeast states of Peninsular Malaysia. 1993, Fatanah 2009, Ramle et al. 2014, Abdullah et Tasek Kenyir is an artificial lake formed by Kenyir al. 2017). Topographically, the Kuala Koh and its Dam or the Sultan Mahmud Hydro-Electric Power adjacent area consist of riverine, largely hill and Station, which took 15 years to be constructed and fully lowland dipterocarp forests. The shaded and humid operate in 1978. Both areas are gazetted as a protected environment encourages the growth of mosses on forest reserve under the Taman Negara (Kelantan) the trees, creating niches suitable for moisture-loving Enactment [En. 14 of 1938] and the Taman Negara epiphytes. In over logged forest, epiphytic orchids are (Terengganu) Enactment [En. 6 of 1939]. These Acts also found growing in abundance on the ground and on are independent from The National Parks Act 1980. rocks, and a few relying on dead debris living as myco- These areas have many geological and biological heterotrophs. However, both terrestrial and epiphytic attractions (Hairul et al. 2016), apart from being home orchids have experienced population declined mainly for the aboriginal tribes of Semaq (Hulu Terengganu) because of habitat degradation and timber extraction Received 27 March 2019; accepted for publication 06 August 2019. First published online: 27 August 2019. Licensed under a Creative Commons Attribution-NonCommercial-No Derivs 3.0 Costa Rica License. 108 LANKESTERIANA process, which have caused many species to near topsoil and nutrient were detrimental for the orchid extinction (Larson 1992, Rauh 1992, Dimmitt 2000, survival (Wan Mohd Shukri et al. 2007). Coupled with Mondragon & Calvo-Irabien 2006). rampant forests destruction in the surrounding areas, the The Orchidaceae is a speciose family of mudslides have also negatively affected the ecosystem considerable significance in horticulture (Hew et al. balance, especially for the forest floor biodiversity 1997), and traditional medicine, with many species in including terrestrial orchids and waterways. various genera having been reported to have therapeutic Deforestation and the global climate change have properties (Pant 2013). Unfortunately, many orchids are been largely ignored by the authority due to lack of naturally rare, endangered, or vulnerable, for climate assessing personnel willing to work in dangerous fragile and habitat changes that are often anthropogenic, and logging sites, thus a stumbling block for conservation from over-collection for horticulture and medicine. efforts to protect forest biodiversity including orchids Some 972 species of orchids in 159 genera have in Malaysia. Because of their ecological, economical been recorded in Peninsular Malaysia (Go & Hamzah and pharmaceutical importance, an exhaustive 2008, Go et al. 2010, Kiew et al. 2010, Ong et al. evaluation on the diversity and ecology of orchids 2017). About twenty percent of them are endemic to in the degraded forest areas is crucial for setting its Peninsular Malaysia (Seidenfaden & Wood 1992, conservation priorities. Hence, this paper focuses on Turner 1995, Ong et al. 2011). Until recently, a total reporting the diversity and distribution of orchids at risk of 245 orchid species were collected from Terengganu in the degraded forests by uncovering the significance and 223 orchid species from Kelantan as documented of ecological alterations that are negatively affecting in SING Herbarium (2018, January), Swiss Orchid their survival and to provide inference for ex-situ Foundation at the Herbarium Jany Renz (2017, July), conservation plans. National Herbarium of the Netherlands (NHN) (2017, July), Turner (1995), and Jaafar et al. (2007). Materials and Methods In recent years, human activities in Kuala Koh Selection of field sampling localities and ecosystems.– and around Tasek Kenyir have directly threatened the The study areas were classified based on the type survivability of biodiversity including orchids. Kuala of disturbance: disturbed secondary forests (DSFs) Koh and its vicinities are now blatantly known to have damaged by mudslides, and logging sites. Observations the highest rate of deforestation in Peninsular Malaysia. and botanical collection trips were carried out in the A large tract of forest near the National Park entrance disturbed forests of Terengganu and Kelantan regions has been cleared for farming, mining and logging from November 2016 until May 2018 (Fig. 1). The (Tuck-Po 2000, Lye 2005, Hairul et al. 2016). Forest areas covered in this study were DSFs in Kuala Koh, clearance has spread extensively to Tasek Kenyir Gua Musang, Kelantan (94.4–129.9 m a.s.l.) and area. The clay exposed cleared land caused surface Air Canal, Tanah Merah, Kelantan (44 m a.s.l.); and water run-off and land erosion due to lack of retention logging sites in Tasek Kenyir, Terengganu (98.8–330.4 from grasses, trees, and shrubs had caused the 2014 m a.s.l.). The disturbed forests were selected based tragic flash floods and mudslides in the lowland areas on whether logging was imminent, currently actively of Terengganu and Kelantan. Based on our empirical logged, and the recent deadly mudslides repercussion. observations, the uncontrolled and unsustainable Eight short line-transect plots of 20 m × 5 m with a timber production might have concurrently shoved the total area of 800 m2 were established in Kuala Koh. epiphytic orchid flora towards local extinction. The Meanwhile, two line-transect plots of 25 m × 5 m were canopy disruptions caused by timber extractions have created in disturbed lowland secondary forest at Air greatly modified the temperature, humidity, and light Canal with the total area of 250 m2. Three logging sites conditions, causing unfavourable habitat for the shade- in the Tasek Kenyir area were selected as study sites. loving species (Gradstein 2008, Benίtez et al. 2015). These sites were located using Google Maps and also Thus, the extremely harsh conditions in the logging based on an earlier preliminary empirical study. Site 1 sites (logged forests) where full exposure to the sun, and Site 2 of active logging were located in Gawi, and water stress, and nutrient-poor soil due to the eroded Site 3 was located in Petuang, with a total area studied LANKESTERIANA 19(2). 2019. © Universidad de Costa Rica, 2019. BESI et al. — Orchid diversity in anthropogenic-induced degraded tropical rainforest 109 FIGURE 1. Coordinates of each studied site recorded in disturbed forests of Terengganu and Kelantan regions. A. Kuala Koh area (DSFs Site 1). B. Gawi area (Logging Site 1). C. Gawi area (Logging Site 2). D. Petuang area (Logging Site 3). E. Tanah Merah area (DSFs Site 2). The map was adapted from http://www.geoplaner.com, a free web-based application that provides several GIS and GPS services. of approximately 53,000 m2. The total area studied in standard herbarium technique after Bridson and Forman the logging sites was calculated based on the distance (2000) and the non-flowering ones were transplanted traveled along the logging road in the logging site into the ex-situ nursery, as living collections, where times the width of 20 m on each side of the road, and they were nurtured until flowering usually within five the orchids were mostly found on fallen trees.