Meteorological and physical conditions of Salt Pan Areas with Filtering-Threaded Technology (TUF) in Cirebon Regency, Indonesia

Salt pans in Indonesia are commonly set in batch operation and highly depend on the meteorological condition. Moreover, the common salt pans are considerably limited in the area (averagely 0.5-1 Ha) as it is not organized by industries or governments; local farmers instead. However, with such confinement, there are some salt pans particularly with filtering-threaded technology system (TUF system) that successfully produce salt with high production (>100 tons/Ha/season) and grade-1 quality. The present study was aimed to get insight on the meteorological condition at the salt pans using TUF system and the physical condition of the sea brine obtained from the TUF in the local salt pans in Cirebon Regency. Measurements on temperatures (air, brine and soil), humidity, wind direction and speed, brine conductivity, brine density and salinity were conducted at the pre-crystallizer pond, brine storage pond, channels, the condenser, and the reservoir. The meteorological parameters were recorded hourly using Automatic Weather Station and the data were taken during 49 hours ly, from August 26-28, 2014 started at 04.00 pm. Meanwhile, the physical parameters of the brine were measured every three hours using water quality meter. The results showed that the meteorological condition, brine physical condition, and the process occurred during salt production were still in agreement and met the theoretical condition or modeling. Even though the relative humidity and some wind speed in the present study area were out of the standard criteria recommended (5m/s for wind speed), the study showed that salt still can be produced in condition of relative humidity (52-88%), wind speed (0.2-5.7 m/s), and ambient temperature (23.2-32.4 oC). Interestingly, it is found that brine thickness and volume could be adjusted to get an optimum temperature of brine (reached 36.2 oC), in order to enhance the evaporation process. The highest soil temperature (34.7 oC) was found at 15.00 in the pre-crystallizer ponds. Meanwhile, the lowest temperature (26.7oC) was found early morning at 04.00 in the reservoir pond. Brine in the pre-crystallizer had highest thermal storage capacity during daytime (06.00-16.00), whereas soil in the pre-crystallizer tended to store heat during the nighttime (18.00-22.00). Brine and soil temperature fluctuation indicate that solar irradiation and convection process transferring heat energy from soil to brine occurs and also took an important part in the evaporation process. It therefore can be concluded that by understanding the condition of meteorology at the salt pan areas and the brine characteristic obtained, the appropriate technology resulting high-quality and quantity salt production could be devised

APLIKASI MODEL NUMERIK KARAKTERISTIK GELOMBANG UNTUK KAJIAN KESESUAIAN LAHAN PENGEMBANGAN BUDIDAYA LAUT DI SITUBONDO, JAWA TIMUR

Model numerik XBeach telah digunakan untuk mensimulasikan penjalaran gelombang laut di perairan Klatakan, Situbondo, Jawa Timur dan hasilnya dipakai untuk analisis kesesuaian lahan budidaya dengan Keramba Jaring Apung (KJA). Data yang digunakan untuk pemodelan ini adalah data batimetri yang diperoleh dari pengukuran langsung, serta gelombang dan angin dari Badan Meteorologi Klimatologi dan Geofisika, dan National Centers for Environmental Prediction-National Oceanic and Atmospheric Administration (NCEP-NOAA) Amerika Serikat. Hasil analisis menunjukkan bahwa tinggi gelombang signifikan perairan Situbondo adalah 0,3 m dengan periode gelombang 4,1 detik dominan dari arah timur sedangkan angin dominan datang dari arah barat laut. Pembudidaya perlu mewaspadai kemungkinan gelombang dengan tinggi mencapai 1,5 m dan angin kuat dengan kecepatan lebih dari 16 m/detik yang terjadi pada awal dan pertengahan tahun. Validasi model dengan perhitungan analitik mengindikasikan XBeach telah melakukan over-estimasi perhitungan tinggi gelombang pada daerah studi dengan kesalahan relatif rata-rata sebesar 16,22% yang diduga disebabkan oleh perbedaan pendekatan pada kedalaman dimana proses shoaling terjadi. Klasifikasi kesesuaian lahan menunjukkan adanya sebaran daerah sangat sesuai hingga tidak sesuai untuk budidaya dengan KJA pada perairan tersebut. Hasil tersebut diverifikasi dengan citra Ikonos melalui Google Earth, dimana terlihat bahwa KJA para pembudidaya terletak di perairan yang dikategorikan sangat sesuai untuk lahan budidaya dengan tinggi gelombang di area tersebut kurang dari 0.6 meter. [Title : THE APPLICATION OF WAVE CHARACTERISTIC NUMERICAL MODEL FOR SITE SELECTION OF MARINE AQUACULTURE DEVELOPMENT IN SITUBONDO, EAST JAVA ] Xbeach numerical model has been used to simulate wave propagation in Klatakan – Situbondo, East Java and the results were used to analyze the site suitability for mariculture using Floating Net Cage (FNC). Parameters used in the model were bathymetric which was obtained from direct measurement, as well as wave and wind data which were obtained from, Indonesian Agency for Meteorology, Climatology and Geophysics, and National Centers for Environmental Prediction-National Oceanic and Atmospheric Administration, respectively. The results showed that a significant wave height recorded in the study area was 0.3 m with wave period of 4.1 s, propagating dominantly from East direction. On the other hand, the wind dominantly moved from north to west direction. The farmers, therefore, need to increase their awareness toward possible high waves of 1.5 m and winds of more than 16 m/s occurred in the beginning and middle of the year. Model validation using analytical approach indicated XBeach has overestimated wave height calculation on the study area with mean relative error of 16,22% due to different approach in depth at which shoaling process occurred. The site classification analysis showed the area distribution for FNC installation varied from unsuitable to very suitable.The result is verified using Ikonos satellite imagery trough Google Earth. It shows that those FNC are located inside the area which is categorized as very feasible for mariculture with the wave height is less than 0.6 m.

Struktur dan Komposisi Tambak Teknologi Ulir Filter untuk Peningkatan Produksi Garam Rakyat

Prinsip utama dalam pembuatan garam teknologi ulir filter adalah evaporasi air laut dengan bantuan sinar matahari melalui pengaliran air pada petakan-petakan berseri dalam proses penuaannya dan penambahan material alam yang berperan sebagai filter. Tulisan ini bertujuan untuk mengkaji kondisi struktur dan komposisi lahan tambak garam TUF sebagai teknologi alternatif yang dapat meningkatkan produksi garam rakyat. Survei, pengukuran secara langsung, pengamatan fisik dan wawancara telah dilakukan di tambak garam rakyat di Desa Ambulu, Kecamatan Losari, Kabupaten Cirebon. Data dan hasil pengamatan yang diperoleh kemudian diolah menggunakan sistem informasi geografis dan dianalisis serta dibandingkan dengan literatur. Hasil penelitian menunjukkan bahwa pada tambak garam TUF dilakukan modifikasi lahan yaitu membuat petakan-petakan memanjang berseri dalam satu kolam kondenser (ulir) dan memperdalam kolam reservoir. Modifikasi pada kolam kondenser mempermudah petambak dalam mengendalikan aliran brine dan memantau kenaikan densitasnya. Diketahui juga bahwa percepatan evaporasi brine pada sistem ini diperoleh dengan menambah pematang tanah. Dari hasil perhitungan diperoleh bahwa pematang yang bersifat konduktor panas ini terdedah radiasi matahari sebesar 112 % untuk ulir besar dan 135 % untuk ulir kecil. Sedangkan modifikasi pada kolam reservoir menghasilkan efisiensi pemanfaatan lahan, dari proporsi 28% terhadap total luas tambak menjadi 75% terhadap total volume tambak. Perubahan struktur dan komposisi tersebut meningkatkan produksi garam hingga mencapai ± 200 ton/ha per musim panen

DISTRIBUTION OF HEAVY METALS IN NATUNA COASTAL WATERS

ABSTRACTThe study of Pb, Cd, Cu, Hg, and As and Fe in Natuna coastal waters, Riau Islands was conducted in November 2012. Water and sediment samples were collected from 35 stations by purposive sampling method and those heavy metals were analysed using Atomic Absorption Spectrophotometer, flame type (FAAS). The results showed that concentrations of total Pb, Cd, Cu, Hg, and As in surface water were below instrument detection limit (2 µg/L for Pb, Cd, and Cu; 0.02 µg/L for Hg and As). Moreover, the concentration of metal Fe in surface water was 0.021-0.054 mg/L. Concentrations of Pb and Cu in sediment were 0.05-22.67 mg/kg and 3.77-11.00 mg/kg, respectively, at which the highest concentrations were found near Binjai Estuary. Those concentrations were significantly below the standard levels set by CCME (2002) and ANZECC/ARMCANZ (2000). Concentration of Fe in sediment varied from 751.13-2309.12 mg/kg and showed similar spatial distribution to Cu-in-sediment. No standard level for Fe in waters was available. Generally, it can be concluded that Natuna coastal water was still uncontaminated.  Keywords: heavy metals, iron metal, Natuna coastal waters

Validasi Metode Analisis Logam Na, K, Mg Dan Ca Pada Air Tua (Bittern) Menggunakan Microwave Plasma-atomic Emission Spectrometer (Mp-aes)

This research aims to obtain analysis method for mayor elements (Na, K, Mg, and Ca) in bittern using Microwave Plasma-Atomic Emission Spectrometry (MP-AES) and to assess the validity of the obtained method. It is known that sea bittern characteristic has complex matrix for its high concentration of the inorganic materials. Therefore assessment of the validity of the analytical method for mayor element is important. The performance characteristics of the method were established by multi-elements-standard-solution assay (Na, K, Mg and Ca), in which samples were un-spiked. Selectivity, linearity, accuracy, precision, detection and quantification limit of the method were evaluated in the study. Matrix effects were not significantly identified for the studied elements. Linearity of selected concentration range for Na, K, Mg and Ca varied from 0.9955- 0.9998. No deviation of true value for all elements was observed in the accuracy test. Meanwhile, precision values of the method (%RSD) were 1.491; 2.702; 2.678; and 1.923, respectively for Na, K, Mg and Ca. The method developed in the present study indicated the detection limits for Na, K, Mg and Ca were 0,184; 0,070; 0,219 dan 0,005 mg/l, respectively, with quantification limits of 0,613; 0,230; 0,730 dan 0,017mg/l. The results of the validation method showed that the proposed method is selective and feasible for sea bittern analysis using MP-AES

Optimalization of Feed Dosage and Frequency in Production of Rotifer (Brachionus Rotundiformis)

The availability of rotifer as live food is importance in a larval mariculture. Therefore a continuous and high production of rotifer is needed. The study was aimed to determine the frequency and dosage of the best food in rotifer culture. Nannochloropsis oculata, yeast and scott\u27s emulsion are used as potential feeds for rotifer. Three dosages of N. oculata (150,000; 250,000, and 350,000 cells/ind.rotifer/day) were applied in the study and were given twice per day. Meanwhile, yeast(0.5 g/106 ind./day) and Scott\u27s emulsion with different dosages (2, 4, and 8 μg/106 ind./day) were given with two different feeding frequencies (two and four times a day) for each dosages. Each treatment was done in triplicates. Sampling of rotifer was conducted in the morning (AM) and afternoon (PM). Water quality (temperature, dissolved oxygen and ammonia) was also measured. Growth and productivity of rotifer were determined from the number of rotifer and the number of rotifer eggs, respectively. The results showed that the optimum productivity of rotifer was achieved by giving N. occulata of 250,000 sel/ind/day, twice a day in four days culture. Meanwhile, treatment with yeast and Scott\u27s emulsion gave best performance when applying 0.5 g/106 and 2 μg/106 ind./day twice per day, respectively. Yeast and scott\u27s emulsion treatment yielded optimum production in two days of culture

Korelasi antara Konduktivitas dengan Jumlah Mineral Terlarut pada Perairan Selatan Pulau Madura

Penelitian ini bertujuan untuk menganalisis jumlah mineral terlarut (Total Disolved Solid/TDS) berdasarkan data konduktivitas (Electrical Conductivity/EC) pada perairan Selatan pulau Madura. Data EC diperoleh dari pengukuran in-situ pada tanggal 24 – 26 April 2013. Penelitian ini dilakukan di perairan Selat Madura pada 7°18’53,1”LS-7°8’58,1”LS dan 113°11’43,4” BT-113°56’14”BT, yang memiliki karakteristik berbeda sesuai dengan keadaan sekitarnya. Perhitungan korelasi antara salinitas dan EC sebesar 0,64, yang diperoleh melalui uji statistik dan menjadi acuan sebagai penentu tingkat kandungan TDS pada keseluruhan badan perairan Selat Madura. Berdasarkan perhitungan kandungan TDS di Selat Madura berkisar antara 33,8 ppm – 35.1 ppm. Hasil analisis diperoleh bahwa tingkat salinitas mempengaruhi daya hantar listrik, serta salah satu komponen dari mineral terlarut merupakan garam-garam yang terdapat pada air laut, hal ini dapat dibuktikan bahwa semakin tinggi tingkat salinitas maka semakin tinggi pula kandungan mineral terlarutnya