Judul: The Relationship Analysis between Bornean Orangutan (Pongo pygmaeus) Population Size and Land Cover Change in West Kalimantan.
Abstrak: Orangutan (Pongo pygmaeus Linnaeus 1760) merupakan spesies kritis dalam Daftar Merah IUCN dan diklasifikasikan dalam Apendiks 1 CITES. Populasinya menurun yang sebagian besar disebabkan oleh hilangnya habitat. Penelitian ini bertujuan untuk mengidentifikasi dinamika ukuran populasi orangutan kalimantan dan menganalisis hubungan antara ukuran populasi orangutan kalimantan dan perubahan tutupan lahan. Data ukuran populasi orangutan kalimantan dari tahun 2014 sampai 2019 di empat lokasi (yaitu Belaban, Bukit Semujan Semangit Menyukung Melingkung, DAS Embaloh Sibau, dan Sungai Putri) diperoleh dari Taman Nasional Bukit Baka Bukit Raya, Taman Nasional Betung Kerihun, Taman Nasional Danau Sentarum, dan Balai Besar Konservasi Sumber Daya Alam Kalimantan Barat. Data tutupan lahan diperoleh dari Direktorat Jenderal Planologi Kehutanan dan Tata Lingkungan, Kementerian Lingkungan Hidup dan Kehutanan. Data yang diperoleh dianalisis menggunakan statistik deskriptif, analisis tutupan lahan, dan analisis regresi linier berganda untuk menguji hubungan antara ukuran populasi orangutan kalimantan dengan delapan variabel, yaitu tutupan hutan, tutupan semak belukar, tutupan pertanian, tutupan lahan terbuka, badan air, kerapatan jalan, kerapatan sungai, dan kerapatan permukiman. Hasil penelitian menunjukkan bahwa ukuran populasi orangutan kalimantan di lokasi Bukit Semujan Semangit Menyukung Melingkung dan Sungai Putri cenderung meningkat. Sebaliknya, ukuran populasi orangutan kalimantan di Belaban dan DAS Embaloh Sibau cenderung berfluktuasi. Tutupan lahan di lokasi Belaban, Bukit Semujan Semangit Menyukung Melingkung dan Sungai Putri cenderung berfluktuasi, sedangkan di DAS Embaloh Sibau cenderung stabil. Ukuran populasi orangutan kalimantan memiliki hubungan dengan perubahan luas tutupan hutan dan semak belukar., Orangutans (Pongo pygmaeus Linnaeus 1760) are critically endangered species under IUCN Red List and classified in Appendix 1 of CITES. Their population is declining which is largely caused by habitat loss. This study aims to identify the dynamics of Bornean orangutan population size and analyze the relationship between bornean orangutan population size and land cover change. Bornean orangutan population size are data from 2014 to 2019 at four locations (i.e. Belaban, Bukit Semujan Semangit Menyukung Melingkung, Embaloh Sibau watershed and Sungai Putri) were obtained from Bukit Baka Bukit Raya National Park, Betung Kerihun National Park, Danau Sentarum National Park, and West Kalimantan Natural Resources Conservation Agency. Land cover data were obtained from the Directorate General of Forestry and Environmental Planning of the Ministry of Environment and Forestry. The data obtained were analyzed using descriptive statistics, land cover analysis, and multiple linear regression analysis to test the relationship between the Bornean orangutan population size and eight variables, namely forest cover, shrubs, agriculture cover, open land, water body, road density, river density, and settlement density. The results showed that the Bornean orangutan population size in the Bukit Semujan Semangit Menyukung Melingkung and Sungai Putri locations tended to increase. On the other hand, Bornean Orangutan population size in the Belaban and Embaloh Sibau watersheds tended to fluctuate. The land cover in the Belaban, Bukit Semujan Semangit Menyukung Melingkung, and Sungai Putri tended to fluctuate, while that in the Embaloh Sibau watershed was steady. The population size of Bornean orangutans is related to forest and shrub cover change.
Keyword: analisis regresi berganda, tutupan lahan, analisis hubungan, orangutan kalimantan, populasi

Judul: Pemodelan Spasial Kesesuaian Habitat Orangutan Kalimantan (Pongo pygmaeus wurmbii Linneaus, 1760) di Suaka Margasatwa Sungai Lamandau, Kalimantan Tengah
Abstrak: Orangutan is categorized as a rare animal since it only exist in Indonesia and its populations tend to decrease, especially in Sungai Lamandau area. The population decreasing is caused by environmental degradation, land conversion, and also hunting. Orangutan population is grouped into critically endangered status according to IUCN Red Listand listed into APPENDIX 1 CITES also by government is protected by Government in Regulation Number 7 Year 1999. Sungai Lamandau Wildlife Reserve is one of the orangutan habitat in Kalimantan. Besides, this location has important value since it is a region which is used as wild conservation of orangutan from rehabilitation. Related to the fact, research of orangutan kalimantan habitat by applying Geographical Information System (GIS) needs to be developed to get spatial data of suitable habitat model for orangutan kalimantan in Sungai LamandauWildlife Reserve. Data collection is done in Sungai Lamandau Wildlife Reserve and in limited usage suggestion zone (Buffer zone). Orangutan kalimantan habitat suitability modeling is done by identifying orangutan kalimantan nest points in spatial to the habitat factors, which is distance by the river and Normalized Difference Vegetation Index(NDVI) value, and disturbance factors via distance with road and distance with the villages. Identification result is analyzed by using Principal Componen Anayisis (PCA) to get value each habitat components so that would be found suitability model with orangutan kalimantan habitat. Habitat suitability map is found by overlaying habitat components to model had built and validated with nest points found in field. Orangutan kalimantan habitat suitability model found is Y=(1,747 x distance with river factor)+(1,747 x NDVI value factor)+(1,215 x distance with road factor)+(1,215 x distance with village factor). Orangutan kalimantan habitat suitability map is divided by three, of suitability which is in low suitability class 6311,70 hectare or 7,88% from overall of research location width, mid suitability class 52378,70 hectare or 65,46% from overall of research location width and high suitability class 21328,60 hectare or 26,65% from overall research location. Validation for low suitability class 0%, mid-suitability class 60,87% and high suitability class 39,13%. Orangutan kalimantan suitability model can be accepted with 100% validation in mid and high suitability class.
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Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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