Judul: Multidimensional of Climate Change on the Distributions of Sumatran Orangutan in the Leuser Ecosystem for Conservation Planning
Abstrak: Sumatran orangutan (Pongo abelii) is one of the three orangutan species (Pongo spp. – Tapanuli: P. tapanuliensis; Borneo: P. pygmaeus) from the great ape family group (Hominidae) that lives in Indonesia. Sumatran orangutan current population in 2015 reached 14,613 individual species based on field survey. Currently, Sumatran orangutans suffered a population declining over the past year due to altered habitat. Climate change also would be expected to increase the extinction risk of the species – thus, many biodiversity, particularly primates will redistribute their habitat. Most Sumatran orangutans (82.5%) are only found in the Leuser Ecosystem, Aceh Province. Due to the range contraction and many threats towards Sumatran orangutans, the species have been considered critically endangered (CR) species based on the International Union for Conservation of Nature (IUCN) red list. Species distribution modelling has been already used for various applications, such as conservation management towards non-human primate species within the protected areas – e.g., the Sumatran orangutan. Nevertheless, there is still a lack of research and information that elaborates climatic shifting effects and habitat degradation towards Sumatran orangutan distribution. The Leuser Ecosystem is the essential habitat for Sumatran orangutans; thus, understanding the climate effects for this species within the area is crucial. In general, the objectives of this research were a) to estimate Sumatran orangutan distribution within the Leuser Ecosystem using species distribution model, b) to identify and quantify exposure of Sumatran orangutan towards climate change and altered habitat, and c) to design conservation strategies for the species. The novelties of this research were: a) Research approach: species distribution modelling approach for Sumatran orangutan within the Leuser Ecosystem using ensemble-method of machine learning (e.g., RF, SVM, MaxEnt, and GLM) based on shared socio-economics pathway with the spatial resolution 100-m; and b) Problem solving: evaluation of Sumatran orangutan vulnerability under climatic pressures, altered habitat, and deforestation using bioclimatic velocity. Furthermore, conservation planning – e.g., habitat restoration and creating the wildlife corridor using least-cost path analysis. In addition, we also provide a new method to estimate the extinction rate of Sumatran orangutans using a macro-ecological approach to assess species adaptivity. This research revealed that the ensemble model from several algorithms (i.e., GAM, GLM, Maxent, Random Forest, and SVM) had outperformed the other algorithms based on discrimination metrics (i.e., AUC, TSS, Kappa, Jaccard, Sørensen). The bioclimatic factor was the essential variable to capture the fundamental distribution of Sumatran orangutan. Orangutan distribution within the Leuser Ecosystem was strongly correlated with the precipitation in the driest quartal and temperature range, affecting food abundance, activity budget, and habitat quality. This result shows that the current Sumatran orangutan distribution covered 37% of the landscape (9915.63 km2). Furthermore, this study also used species distribution model output to estimate population density and metapopulation within the habitat patches. The density model of Sumatran orangutan has a relatively similar pattern to the previous study. Climate and habitat changes jeopardized tropical biodiversity, including Sumatran orangutan within the Leuser Ecosystem. This landscape will suffer a tremendous climatic anomaly (i.e., precipitation and temperature) in the northwest, southeast, and montane areas of the Leuser Ecosystem. Besides, high-temperature anomalies
Keyword: Leuser, makroekologi, model distribusi spesies, orangutan sumatera, perubahan iklim

Judul: Habitat analysis and population estimation of sumatran orangutan (Pongo abeii Lesson 1827 at the Forest of Batang Toru, North Sumatra
Abstrak: The Batang TofU forest located in North, Center and South of Tapanuli, North Sumatra was recently found as one of Sumatran orangutan population habitat. A survey of trees species, nesting behavior and population of Sumatran orangutan was carried out during October 2007 up to January 2008 and aimed to analyze: (1) the forest structure, composition and trees distribution (including feeding and nesting trees); (2) estimated density and popUlation; and (3) the threat factors influenced the survival of Sumatran orangutan in Batang TofU forest. The results of the inventory of trees with diameter at breast height (DBH) 2: 10 cm in 3.84 ha areal sampling showed that 274 species in 56 families, represented by 1,896 individuals with total basal area of 148.9 m2lha and density of 498 treeslha. This forest was richer in tree species than other lowland forests in North Sumatra, Borneo and the Malay Peninsula and was dominated by Sapotaceae trees. The most prominent species were Tristania maingayi, Casuarina sumatrana, Quercus sumatrana and Ganua motleyana in every types of forest and differenced with Batang Gadis National Park which dominated by Dipterocarps. There were 96 feeding trees species in 25 families, represented by 536 individuals with total basal area of 46.7 m2lha. The prominent heights of feeding trees were below 30 m and distributed abundantly in the old moist secondary forests. The most important feeding trees for orangutans (Diospyros sp., Eugenia sp., Nephelium sp., Lithocarpus sp., Ficus sp., Artocarpus sp., Durio sp., and Garcinia sp.) were abundantly found in the old moist secondary forests, too. Orangutans commonly prefer to nest on the top of tree bar and the main branch of trees (DBH 20-30 cm; heights 15-20 m), especially in the middle canopy (20-30 m). Considering that there were enough feeding trees in this canopy. The most preferred nesting trees genus/species were Quercus sp., Syzygium sp., Shorea sp., Diospyros sp. and Lithocarpus sp. It was also invented 267 orangutan nests along 40.125 km cumulative lengths of line transects or equal with 0.54 percent of study area conducted at 11 sites. Densities were found higher in the old moist secondary forest while it was conversely lower density in the mixed forest. The distributions of nests were tended to clumped, related to the distribution of feeding trees. Orangutan population in 748.86 km2 ha potential habitat was approximately 337-421 individuals. Their distribution was limited by elevation and food availability. Human activities such as land conversion for agriculture purposes had become important factors affecting orangutan distribution. Field fact finding showed that many orangutan direct sightings and nests were located much closer to area human activities and logging concessions. This eventually has become real and concreted threat to their remaining population. It's needed to conduct further research in long-term monitoring and develop a strategic planning which promotes community involvement for the conservation of orangutan.
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Judul: Electrophoretic Coating of Apatite Compouds on Stainless Steel 316L.
Abstrak: Stainless steel (SS) 316L is a metal which is used to bone plate. However, this metal still has low biocompatibility in a human body. The metal is coated by HAp in order to increase its biocompatibility. HAp on SS 316L is coated by electrophoretic deposition (EPD) method. We used two variables in EPD process, such as voltage and coating time to obtain the best coating. The XRD difractogram showed that SS 316L has been coated by HAp. Physical observation used by microscope optics showed that the best coating is achieved on 120V during 2 minutes.
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