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"ABSTRACTMetan adalah salah satu gas rumah kaca yang memiliki kontribusi dalam proses pemanasan global. Sumber utama metana adalah lahan basah yang salah satunya adalah ekosistem mangrove. Metana di ekosistem mangrove dihasilkan dari penguraian bahan organik di dalam sedimen oleh mikrorganisme anaerobik yang dikenal dengan nama bakteri methanogen. Besarnya metana yang dihasilkan dipengaruhi oleh aktivitas mikroorganisme, kondisi lingkungan dan atribut bahan organik. Tulisan ini mengulas tentang atribut atribut bahan organik dan pengaruhnya terhadappembentukan metana di sedimen mangrove. Hasilnya menunjukkan bahwa kandungan karbon oganik total (TOC) dalam bahan organik berperan besar sebagai sumber karbon dalam pembentukan metana. Semakin besar kandungan TOC semakin besar pula produksi metana. Rasio unsur karbon dan nitrogen (C/N) dalam bahan organik juga memiliki peran penting. Rasio C/N yang tinggi akan menghambatpertumbuhan bakteri methanogen akibat kurangnya nutrisi sedangkan rasio C/N yang rendah akan menghasilkan amoniak yang bersifat toksik untuk methanogen. Produksi metana yang melimpah dihasilkan dari bahan organic mudah terurai yang mengandung sedikit lignin yang umumnya berasal dari makroalga laut. Selain itu, metana akan banyak dihasilkan jika bahan organik memiliki ukuran pori yang besar dan tidak terlindungi secara kimiawi atau tidak berikatan dengan mineral."

"ABSTRACTPhylogenetic taxonomy or cladistics is a classification system based on evolutionary history of an organism with other organisms, so that the process of evolution can be reconstructed. The main principle of the classification system is that only the unique characters of the adjacent group owned by descendants of an ancestor that was used in classifying organisms and secondly the reconstruction is based on group monophyly. So, the purpose of the use of this method is to classify organism and reconstruct the phylogenetic relationship based on the character encoding. Similarities and differences in the characters shown by a certain code lead to a tracing ancestors of each species. Several methods to reconstruct the phylogeny tree using qualitative data base are Maximum Parsimony and Maximum Likelihood. Study phylogeny based on morphological characters has a fundamental weakness which ultimately requires molecular characters to cover up these weaknesses."

"ABSTRACTThe use of reference toxicant in aquatic toxicity testing is a part of efforts to obtain good quality data and it can be justified scientifically. It is used to determine the health and sensitivity of the test on organisms; to compare relative toxicities of substances by using control as an internal standard; to perform interlaboratory calibrations; and to evaluate the reproductive ability on tested data with time. Numbers of substances, such as some metals and salts, can be used as reference toxicants, but basically we must consider certain criterias in using a chemical as a reference toxicant. An ideal reference toxicant is that has a toxic at low concentrations, rapidly lethal, non selective, and detectable by known analytical techniques. The use of each reference toxicant in toxicity tests should be repeated using the same test organism to produce a data set of sensitivity. Endpoint values are then plotted on a control chart with tolerance range 2 SD. The value outside the tolerance range requires the evaluation of all test procedures and conditions of the test organisms."

"ABSTRACTCarrageenan is apobrsaccharide sulfate extracted flat red seaweed (Rhodophyceae). Carrageenan constituent, which are in the hydrocolloid form, are capable to produce composites, has the potential to be used as a biodegradable packaging material. The use of carrageenan based edible film packaging is a good alternative to improve endurance and quality of food products during the storage. The success in the making of edible film can be seen in the characteristics of the edible film products. Characteristics of edible film that are used as parameters including the thickness, tensile strength, water vapor transmission rate and the solubility of the film."

"ABSTRACTArchaster typicusis is one of the target sea star for the ornamental trade in many locations in Indonesia. The trading of this sea star is not only traditionally in the gift shop at tourism area but also in the online shop. The ecological impact related to the high exploitation of this species in Indonesia has not much been examined. This review informs about the biological and ecological aspect of Archaster typicus, including systematics, habitat shifting, burrowing behavior and mating behavior: Thus information expected to deliver a basic knowledge to the society, academicians, researchers who intend to examine the ecological role of this species and also as basic information for the future conservation management."

"ABSTRACTAir poros sedimen menyimpan informasi penting tentang status geokimia dan ekologi sedimen sehingga analisis air paras sedimen sering dilibatkan dalam studi ilmu lingkungan. Secara umum pengambilan air paras sedimen dapat dilakukan dengan dua metode yaitu ex situ dan in situ. Metode ex situ dilakukan dengan mengambil sedimen dari Iapangan kemudian air poros diekstraksi di laboratorium menggunakan leknik peras (squeeze) dan juga teknik sentrifugasi. Sedangkan metode in situ dilakukan dengan mengambil air paras langsung dilokasi menggunakan teknik hisap (suction) dan juga teknik dialysis. Artikel ini akan mengulas tentang ke empat teknik pengambilan sampel air poros sedimen yang umum digunakan beserta kelebihan dan kekurangan masing masing teknik. Dari keempat teknik tersebut, tidak terdapat teknik yang paling unggul dan paling dianjurkan penggunaannya dibandingkan dengan teknik yang lainnya. Pemilihan teknik yang tepat harus disesuaikan dengan tujuan dari pengambilan sampel itu sendiri."

"ABSTRACTOceans cover 70 percent of the Earth surface. Coastal and shallow water areas contain the most productive and diverse ecosystem, including coral reefs, mangroves and sea grass beds. Coral reefs, as referred to the tropical rainforest of the ocean, is a marine system whose valued about 30 million USD per year: Coral protects shares and islands from the strong waves and surges. Along with sea grass beds and mangroves, coral reefs acts as the biggest carbon sink from atmosphere in the earth. The tropical coral reefs worldwide cover an area of 284. 000 km2 can absorb carbon as much as 4 milion tons carbondioxide every year: It is five times higher than tropical rain forests can absorb. It is why people called it as blue carbon. On the other hand, some people say that coral reef is also acts as the carbon source."

"Detects the sound frequency range of fish, the intensity of the sound amplitude, sound fluctuations, and shape the sound patterns of the fish. Passive acoustic methods used to monitor marine mammals expressed. In general, the signal obtained from the animal record sounds is poor and difficult to determine from which directions it is produced, therefore it requires that require amplification strengthening. Bioacoustic research is needed to identifies the communication language (Acoustic communication) in mammals. Bioacoustic detect mammal produced frequency ranges of sound, amplitude intensity of sound, voice fluctuation, and form sound patterns of mammals. Studying bioacoustic is inseparable from the science of underwater acoustics, biology of mammals, and the study of mammalian behavior: Generally bioacoustic include physiology of mammals organ that produce sound, earning voice mechanism, sound characteristics of mammals, mammals sound approaching mechanism, the hearing capacity of fish, and the evolution of the auditory system, and to obtain the fequency range of each sound produced by the dolphins (mammals). Environmental conditions and parameters (salinity and temperature) will greatly affect the value of the intensity and frequently generated the target, the more extreme the environmental conditions, the lower value of the intensity and frequency generated."

"ABSTRACTThe genus Ulva (Phyllum Chlorophyta, Family Ulvaceae) is a kind of green seaweed which has been exploited for many purposes is very rich in bioactive compounds that are important for medical purposes, such as anti coagulan, anti cancer; anti oxidant, anti microbial and anti influenza. Ulva has been used for a long time but still lack of cultivation techniques lnformation about the characteristics and biological aspects of Ulva is important for basis technology of Ulva cultivation, including reproductive biology, habitat, distribution and commercial uses of Ulva. The technology of Ulva cultivation is expected to reduce exploitation of Ulva in the wild."

"ABSTRACTThis article presents general knowledge about crab Huenta spp. belonging to the family Majidae. Eventhough this title seems very simple, but it actually cover many information, starting from its unique body, carapace shape, camouflage, biosystem atics, its life in the nature."