Judul: Study on the Identification, Bioaccumulation and Exposure Assessment of Organic Contaminants in Jakarta Bay
Abstrak: The Jakarta Special City is known as the top ten megacities in the world with more than 10 Mio inhabitants, while including the suburb area of Jabodetabek Metropolitan Area (JMA) is listed as the 4th largest agglomeration after Guangzhou, Tokyo and Shanghai, with a population of ~30 million (OECD 2014, Demographia 2015). Tremendous development of JMA has implicated huge amount of waste, produced either from municipal sewage or industrial disposal. Due to inadequate infrastructure and poor management, at least 2,000 Ton/day (18 %) of solid waste in JMA are not properly collected and transported to the official landfills, while only 2 % of the households are connected to a centralized sewage treatment, 88 % population minimally treat the waste individually, whereas 10 % of them deliver their waste water directly in to the rivers, and thus potentially dumped through the 13 main rivers flowing to Jakarta Bay (BPLHD Jakarta 2012). Through bioaccumulation and biomagnification pathways, hydrophobic harmful contaminants will accumulate in the aquatic animals (fish and shellfish). Long term exposure of harmful contaminant over the threshold will consequently promote human health risk on the population. The objective of the present study was to determine persistent and emerging organic contaminants in water, sediment and biota (fish and shellfish) of Jakarta Bay and to link the contaminants to the main emission sources. Furthermore, study on the bioaccumulation profile was carried out to understand the fate of selected contaminants accumulate in different tropical seafood (fish and mussel). A non-target screening approach using gas chromatography-mass spectrophotometry (GC/MS) was employed in order to identify a wide range of organic contaminant in different compartments (sediment, water, seafood), instead of commonly targeted/specific approach. In order to estimate the exposure of selected harmful contaminants on the concerned population, seafood consumption rate was recorded through 152 respondents from 2 sub districts in North Jakarta, 1 district in Tangerang and 1 district in Seribu Island. In the same time, 14 seafood species were collected directly from the Jakarta Bay during the dry and wet seasons in 2012 and 2013 for the determination of organic contaminants. Output of the study was qualitative and quantitative characterization of organic contaminants, their distribution within the aquatic environment of Jakarta Bay and a source emission profile as well as the potential health risk on the concerned population. This study demonstrated the usefulness of a non-target GC/MS screening for assessing persistent and emerging organic contaminants in aquatic environment. Identification in sediment samples has revealed more than 60 organic compounds from the whole fractions either non-polar, semi-polar or acidic-polar compounds, more than 40 compounds in green mussels (Perna viridis), more than 30 substances in various fishes, and at least 15 contaminants in banana shrimp (Penaeus merguiensis). The substances comprised of persistent organic pollutants including dichloro-diphenyl-trichloroethane (DDT) and its metabolites (DDX) as well as high molecular weight polycyclic aromatic hydrocarbons containing 4 aromatic rings or more (HMW-PAHs). The majority of emerging contaminants detected in the..dst
Keyword: Organic contaminant, environmental pollution, bioaccumulation, exposure assessment, Jakarta Bay

Judul: Sebaran Konsentrasi Fosfat (PO4-P) dan Nitrat (NO3-N) sebagai Indikator Kesuburan Perairan di Teluk Jakarta
Abstrak: Teluk Jakarta terletak di pantai utara Pulau Jawa merupakan muara bagi 13 sungai besar di Jakarta, Bogor, Depok, Tangerang, dan Bekasi. Berbagai aktivitas yang melibatkan pemanfaatan perairan baik teluk maupun sungai dapat menyebabkan penurunan kualitas perairan dan pengayaan nutrien. Salah satu akibat pengayaan nutrien yaitu peningkatan nutrien seperti fosfat dan nitrat yang dapat memengaruhi produktivitas perairan. Penelitian ini bertujuan menganalisis sebaran konsentrasi fosfat dan nitrat di Teluk Jakarta secara spasial dan temporal. Pemantauan kualitas air dilakukan antara tahun 2012 hingga 2019 sebanyak delapan kali pengamatan dari 23 stasiun. Penentuan 23 stasiun berdasarkan keterwakilan wilayah Teluk Jakarta. Berdasarkan kandungan fosfat dan nitrat, perairan Teluk Jakarta terrmasuk subur. Pola sebaran spasial fosfat dan nitrat konsentrasinya lebih tinggi di sekitar pantai dan semakin rendah seiring mendekati mulut teluk. Secara temporal, konsentrasi fosfat dan nitrat menunjukkan perbedaan yang signifikan cenderung meningkat dari tahun ke tahun., Jakarta Bay is located on the north coast of Java Island and is the mouth of 13 major rivers in Jakarta, Bogor, Depok, Tangerang, and Bekasi. Various activities that involve the use of waters, both bays and rivers, can cause a decrease in water quality and nutrient enrichment. One result of nutrient enrichment is an increase in nutrients such as phosphate and nitrate which can affect water productivity. This study aims to analyze the spatial and temporal distribution of phosphate and nitrate concentrations in Jakarta Bay. Water quality monitoring was carried out between 2012 and 2019 in eight observations from 23 stations. Map of 23 stations based on the representativeness of the Jakarta Bay area. Based on the content of phosphate and nitrate, the waters of Jakarta Bay are considered fertile. The pattern of spatial distribution of phosphate and nitrate concentrations is higher around the coast and lower as they approach the mouth of the bay. Temporally, the concentrations of phosphate and nitrate showed significant differences which tended to increase from year to year.
Keyword: temporal, Jakarta Bay, nitrate, phosphate, spatial

Judul: Konstruksi Hukum Grup Kurva Eliptik Atas F3m
Abstrak: Elliptic curves upon F3m can be divided in two cases, i.e. supersingular and nonsupersingular case. Based on group laws on elliptic curves, a new arithmetic upon F3m can be formulated as an addition process of two random points on the curve. This addition process can then be applied to the ElGamal algorithm.
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