Didik Widyatmoko

The processes that threaten Indonesian plants

The processes that threaten 240 Indonesian threatened plants were identified and categorized based on a comprehensive review of the published literature and elicitation of information from experts. Intrinsic biological factors and habitat loss are the major causes of plant endangerment in Indonesia (affecting 83 and 82 of species respectively), followed by overexploitation (64) and natural factors (6). The dominant threats vary between major plant groups, with habitat loss being particularly important for palms and trees, and biological factors important for orchids. For all studied plant species three sets of inter-related threatening processes (threat syndromes) were identified that differed among the major plant groups. By identifying and evaluating the processes that threaten plants in Indonesia we provide knowledge to guide their future conservation. © 2011 Fauna & Flora International.

Kajian Pemilihan Jenis Tumbuhan Untuk Restorasi Hutan Berdasarkan Beberapa Parameter Fotosintesis

Forest restoration is a process of ecosystem conditioning (soil, vegetation, and wildlife) in order to achieve similar patterns and profiles to previous conditions and status before the ecosystem was disturbed, both in terms of species composition and structure, and habitat functions. Restoration is a crucial part to maximize the conservation values of biodiversity and ecosystem functions. Eight different native plant species were assessed in this research while the photosynthetic parameters studied included the total chlorophyll content, carbohydrate content, CO2 sequestration capacity, leaf weight, leaf number, leaf area and leaf water content. Spectrophotometer was operated to analyse chlorophyll content, the Somogyi-Nelson method was used to calculate carbohydrate content, and leaf area was measured using the leaf area meter. The research results using the principal component analysis showed that each type of the plant species used for the restoration (2 years old after planting) had different characteristics in terms of photosynthetic parameters studied. Dacrycarpus imbricatus and Syzygium lineatum both had the highest carbohydrate contents and the best abilities to absorb CO2. Sloanea sigun, Alstonia scholaris, Manglietia glauca, and Castanopsis argentea had higher total chlorophyll contents than others, while Altingia excelsa, M. glauca, A. scholaris, and Schima wallichii had higher water contents. A. scholaris, M. glauca, and S. sigun had heavier leaf weights. In contrast, M. glauca possessed the widest leaves amongst the species observed. Keywords: forest restoration, photosynthetic parameters, native species