Abstract. Artificial reefs are artificial habitats laid in waters by mimicking some of the characteristics of natural reefs; and could be made of different materials, one of which is concrete. Seashell waste and stone ash could be added as an alternative material to the concrete for artificial reefs. The purpose of this research is to access the growth rate of Acropora muricata coral fragments transplanted on the hollow dome-shaped concrete with three different compositions: C1), conventional concrete, composed by a mixture of Portland cement, sand, and gravel (composition was 1:3:2); C2), a mixture of Portland cement, sand and crushed bivalve's shells (composition was 1:3:2); and C3), a mixture of Portland cement, stone waste (stone dust), sand and crushed bivalve's shells (composition was 1:3:3:2). Observation of coral fragment growth was conducted underwater by Scuba diving for 6 months with observed parameters were fragment length, colony diameter and number of branching. The highest rate of fragment lengthening of A. muricata coral fragment was at C2 (1.019±0.081 cm/month) and C1 (1.014±0.076 cm/ month). The highest colony diameter increment was also in C2 (1.903±0.212 cm/month) and C1 (1.856±0.219 cm/month); while largest number of branches was also in C2 (13.31 or 2.21 branch/month) and C1 (12.56 or 2.09 branch/month), respectively. Based on one-way ANOVA and Tukey's HSD test (p = 0.05), there is no significant difference in fragment lengthening and colony diameter in C1 and C2 model, yet differed significantly with C3 model.

For the first time, the processes controlling the variations of mixed layer temperature (MLT) and salinity (MLS) in the Banda Sea are quantified using data from a single Argo float in combination with satellite and reanalysis outputs from August 2017 to August 2019. This augments previous studies that utilized ocean model data only. We document the presence of a barrier layer and quantify the roles of air-sea heat and mass exchanges, horizontal advection, and vertical entrainment in the seasonal variability of MLT and MLS. We find that heat gains and losses at the air-sea interface are the main contributor to the warming and cooling of the MLT. Seasonal changes in MLS are driven by advection of low salinity water rather than freshwater fluxes from precipitation and evaporation. This is particularly the case during the late northwest and monsoon transition period from February to April when low salinity is advected eastward from the Java Sea into the Banda Sea.

Kajian hidro oseanografi digunakan untuk menentukan lokasi penempatan dermaga apung yang sesuai di Pulau Liwungan Kabupaten Pandeglang-Jawa Barat.  Dermaga apung di pulau tersebut nantinya akan digunakan sebagai pendukung kegiatan wisata bahari. Penggunaan dermaga apung dipilih karena mempunyai beberapa keunggulan dibandingkan dengan dermaga konvensional, utamanya dari segi biaya dan kemudahan pemasangan. Akan tetapi, dermaga jenis ini mememerlukan kondisi fisik perairan yang spesifik. Pada studi ini, dilakukan analisa terhadap faktor fisik perairan yang berpengaruh, yaitu kondisi gelombang dan pasang surut, melalui pengamatan lapangan dan pemodelan numerik dengan MIKE 21. Gelombang signifikan pada perairan Liwungan berkisar 1,1- 2 meter dengan rata-rata 1,8 m. Pasang surut mempunyai tinggi tunggang 1,66 meter, dengan  tipe pasang surut campuran condong ke harian ganda. Hasil analisa menunjukkan letak perairan yang sesuai untuk penempatan dermaga apung berada di bagian tenggara pulau Liwungan dengan dasar perairan yang relatif lebih curam dengan kemiringan 8,5°. Lokasi tersebut relatif terlindung dari serangan gelombang  dengan tinggi gelombang maksimum pada titik pemasangan dermaga apung hanya 1,35 meter (periode ulang 25 tahun).

ABSTRAKPusat Pengkajian dan Perekayasaan Teknologi Kelautan dan Perikanan (P3TKP) -KKP telah mengembangkan perangkat keras elektronik log book penangkapan ikan (ELPI) berbasis GPRS, dengan fungsi utama untuk input data tangkapan ikan secara elektronik. Alat ini juga dilengkapi dengan fitur rekam jejak kapal yang diprogram untuk mengirimkan data posisi koordinat setiap periode tertentu secara otomatis. Data rekam jejak kapal ini dapat diintegrasikan dengan sistem pemantauan kapal perikanan atau VMS yang dikelola oleh Direktorat Jenderal PSDKP -KKP. Penelitian ini bertujuan untuk mengintegrasikan sistem ELPI dengan sistem VMS offline. Penelitian ini terdiri dari beberapa tahap, yaitu perancangan perangkat lunak pada ELPI untuk mencatat rekam jejak kapal secara otomatis setiap 30 menit, perancangan perangkat lunak untuk integrasi sistem ELPI dengan VMS, serta pengujian di lapangan. Uji coba pengiriman data ELPI dibagi ke dalam dua server yaitu server P3TKP dan server VMS offline yang ada di PSDKP. Pada uji coba, data posisi koordinat berhasil terkirim ke server P3TKP dan server PSDKP setiap 30 menit secara otomatis, di mana data rekam jejak kapal tersebut dapat terlihat pada peta yang berada di perairan selatan Jawa Barat. Dengan terintegrasinya kedua sistem ini diharapkan dapat memperkuat pengumpulan data posisi kapal ikan khususnya kapal di bawah ukuran 30 GT. Kata kunci: ELPI, VMS, integrasi, rekam jejak kapal, kapal perikanan ABSTRACT Research and Development Centre for Marine and Fisheries (P3TKP) -KKP has developed hardware of electronic fishing log book (ELPI) with the primary function for input the catch fish data electronically. It is also equipped with vessel tracking feature programmed to submit coordinate position data any definite period automatically. This vessel tracking data can be integrated with the Vessel Monitoring Systems run by the Directorate General of PSDKP -KKP. This research is aimed at integrating ELPI with the offline system of VMS. Research is composed of several stages

Central Java has several estuaries which highly populated in their area, generating high load of waste water discharge. Research conducted on two of the estuaries, Comal estuary in Pemalang and Garang estuary in Semarang. Waste water discharge from population around upstream river of Comal and Garang pollute both estuaries, which are in north coast of Central Java. The aim of this research is to determine the amount of pollutants which enter the estuary and become sediment in Comal and Garang river estuary. The amount of pollution has been analyzed by QUAL2Kw program which then the result would be input data for sediment analysis using MIKE 21 ECOLab program. The result of research state that Comal estuary has BOD concentration of 4.26 mg/L on west season and 4.21 mg/L on east season. While Garang estuary has BOD concentration of 18.21 mg/L on west season and 4.73 mg/L on east season.