Judul: Impact of heavy metal content on the polymorphism occurrences of badukang fish (arius maculatus fis & bian) and sembilang fish (plotosus canius web & bia) in the Estuary of Kahayan and Katingan Rivers, Central Kalimantan
Abstrak: Penelitian ini dilakukan di perairan muara Sungai Kahayan dan Katingan, Kalimantan Tengah. Air hujan yang mengalir di atas lokasi pertambangan, bekas kebakaran hutan dan gambut, pengawetan kayu, pertanian, perkebunan, pemukiman menyebabkan pencemaran. Tujuan penelitian ini adalah: (1) Mengaji sifat fisik, kimia perairan dan pengaruhnya terhadap struktur komunitas biota laut di muara Sungai Kahayan serta Katingan. (2) Mengaji kandungan logam berat dalam lingkungan perairan dan biota; kemampuan (bioconcentration factor-BCF) biota laut mengakumulasi logam berat yang terkandung dalam habitat; keter-kaitan kandungan logam berat dalam biota laut dengan yang terkandung dalam habitat. (3) Mengaji pola sebaran akumulasi Hg, Cd dan Pb dalam jaringan organ tubuh ikan serta pengaruhnya terhadap morfologi jaringan organ tubuh ikan Badukang dan Sembilang. (4) Mengaji kandungan dan pola sebaran akumulasi Hg, Cd, Pb yang berpotensi menyebab-kan kemunculan polimorfisme pada tulang sirip keras ikan Badukang dan Sembilang di- muara Sungai Kahayan serta Katingan. Penelitian ini menggunakan metode survei dan pengambilan contoh purposive sampling. Peralatan yang digunakan selama penelitian: Kammerer bottle water sampler, Petersen grab, DO meter, pH meter, Salinometer, Current meter, Deph sounder, Eh meter, plankton net (20 μm), mikroskop, saringan makrobentos, mikrotom, seperangkat alat destruksi dan Atomic Absorption Spectrophotometer (AAS).
Keyword: Arius maculatus Fis & Bian, Plotosus canius Web & Bia, Central Kalimantan, Salt wedge estuaries, Partially mixed estuaries, Vertically homogeneous estuarine, Sectionally homogeneous estuarine or Fjord

Judul: Assessment on Heavy Metals (Hg, Cd, and Pb) Contamination in Kapuas Estuary Waters, West Kalimantan
Abstrak: Various activities of the communities along the Kapuas River in West Kalimantan, such as domestic, transportation, harbor, and industries have an impact on the environment through waste water. Illegal gold mining in the upstream region also contributed to the decline in the quality of the Kapuas River. The existence of toxic metal in water and sediment could threaten the environmental health of the Kapuas Estuary through the process of bioaccumulation and biomagnification in the food chain, and threatens the sustainability of marine fishery products eventually. The availability of accurate data on the condition of the waters of the Kapuas Estuary is absolutely necessary. This is particularly useful in formulating strategic and anticipatory policies for the management of the marine environment and natural resources in the coastal areas of West Kalimantan. This study aims to determine the concentration and distribution of Hg, Cd, and Pb in the Kapuas Estuary as information for integrated management of the coastal marine environment in West Kalimantan. This research was conducted in April and September 2011 in the Kapuas River and coastal waters of the Kapuas Estuary with 20 sampling stations. Analysis of dissolved Hg refers to SNI 19-6964.2-2003, whereas analysis of dissolved Cd and Pb refers to Standard Methods for the Examination of Water and Wastewater 3111C. Analysis of Hg in sediments and TSS refers to US EPA 245.5 methods, whereas analysis of Cd and Pb in sediments and TSS refers to US EPA method 3050B. Analysis of Hg in fish tissue was based on the AOAC Official Method, whereas analysis of Cd and Pb refers to ASEAN Canada CPMS II. Physico-chemical characteristics of water such as salinity, pH, dissolved oxygen, temperature, TSS concentration and sediment characteristics (grain size and organic matter content) were also measured to determine the condition of the waters at the time of sampling. Physico-chemical characteristics of the Kapuas Estuary is characterized by a range of salinity between 0-31 psu. pH values varied between 3.24-5.11 in the Kapuas River, and 5.82-8.21 in coastal areas. Temperatures in the Kapuas River basin ranged from 28.4-30.0 °C, while in coastal areas varied between 21.1-32.2 oC. Dissolved oxygen concentration in the Kapuas River basin ranged from 4.74-5.60 mg l-1, while in coastal areas ranged from 4.5-6.8 mg l-1. Total suspended solids (TSS) had variation of the concentration between 56.90-107.80 mg l-1 in the Kapuas River, and 16.50-230 mg l-1 in the coastal areas. Dissolved Hg concentrations in the Kapuas River basin ranged from 0.05 -0.49 mg l-1, while in coastal areas ranged from <0.001-0.80 mg l-1. Hg concentrations in TSS in the Kapuas River basin ranged from 1.00-2.59 mg kg-1 dry weight, while in coastal areas varied between 0.20-4.01 mg kg-1 dry weight. Dissolved Cd concentrations ranged from 0.05-0.63 mg l-1 in the Kapuas River, and <0.001-0.73 mg l-1 in the coastal areas. Cd concentrations in TSS in the Kapuas River basin ranged from 21.66-69.33 mg kg-1 dry weight, while in coastal areas varied between 3.18-85.37 mg kg-1 dry weight. The concentration of dissolved Pb in the Kapuas River basin ranged between 2.15-3.44 mg l-1, while in
Keyword: pollution, heavy metals, water, sediment, fish, Kapuas Estuary

Judul: Truncated Stop Loss as a Optimal Solution of Reinsurance Agreement in One-Period Model
Abstrak: Reinsurance is one of risk management efforts of an insurance company, which is called the cedent. Similar with insurance, reinsurance constitutes the cedent to pay the premium. We consider one-period reinsurance model and derive a rule which minimizes the ruin probability of the cedent for a fixed reinsurance premium. Therefore, it is needed to construct an optimal reinsurance agreement for the cedent. The premium is calculated according to four different principles, i.e. economic, generalized zero-utility, Esscher, and mean-variance principles. Stop loss is a reinsurance contract which protect the insurance company for losses that exceed a certain amount. The result of this research shows that a truncated stop loss is an optimal agreement in the class of all reinsurance contracts with various premiums calculated using above mentioned principles.
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