The waters of Pangandaran is one of area potential spread of spiny lobster in the southern of West Java. Species of spiny lobster that caught in waters Pangandaran including: Panulirus homarus, P. penicillatus, P. ornatus and P. versicolor. Measurement of spiny lobster conducted in November-December 2015 and January-February 2016 to determine the population size distribution and condition factor of spiny lobster. The result of measurement on 826 individuals spiny lobster, showed distribution size of male spiny lobster ranged from 3.1-8.9 cm (CL), while the female ranged from 3.4-8.5 cm (CL). The result of analysis of length weight relationship, spiny lobster in Pangandaran has isometric growth pattern. The values of coefficient of fulton condition (K) and relative weight (Wr) values result of the analysis, indicating that the waters Pangandaran not quite support for the growth of spiny lobster.

Danau Towuti merupakan danau terbesar di kompleks Danau Malili, Sulawesi Selatan dan danau terbesar kedua di Indonesia setelah Danau Toba. Danau Towuti termasuk danau dengan tingkat endemisitas tinggi untuk jenis ikan perairan umum. Penelitian ini bertujuan untuk mengetahui kualitas perairan dan potensi produksi ikan di Danau Towuti. Penelitian ini dilaksanakan dengan tiga kali survei di tahun 2008. Aspek ekologi yang diamati terdiri atas beberapa parameter fisika, kimia, dan biologi perairan. Potensi produksi ikan dihitung berdasarkan pada hasil pengukuran produktivitas primer dari setiap stasiun penelitian. Hasil penelitian ini menunjukkan bahwa kualitas perairan Danau Towuti, baik secara fisik, kimia, dan biologi mendukung kehidupan dan perkembangan ikan.Berdasaran pada nilai kandungan phosfat, nitrat, plankton, produktivitas primer dan kandungan khlorofil-a, Danau Towuti diklasifikasikan dalam oligo mesotrofik yaitu tingkat kesuburan rendah sampai sedang. Potensi produksi ikan Danau Towuti dari hasil pengukuran produktivitas primer adalah ±195 ton/tahun.

PENDAHULUANLobster merupakan sumber daya perikanan yang memiliki nilai ekonomis tinggi (Nurfiarini et al., 2016) dan menempati urutan ke empat komoditas ekspor dari kelompok udang-udangan (Junaedi et al., 2010). Di Indonesia, ditemukan sebanyak tujuh jenis spiny lobster dari Famili Palinuridae yaitu Panulirus homarus (lobster pasir), P. ornatus (lobster mutiara), P. longipes (lobster batik), P. versicolor (lobster bambu), P. polyphagus (lobster pakistan/lumpur), P. penicillatus (lobster batu) (Phillips, 2006;Tewfik et al., 2009), dan Puerulus mesodontus (Wardiatno et al., 2016). Kalih (2012) ABSTRAKSampai saat ini, informasi mengenai kebiasaan makan, luas relung dan tumpang tindih relung mengenai lobster di Indonesia belum banyak diketahui. Tujuan penelitian ini adalah mengkaji kebiasaan makan, luas relung dan tumpang tindih relung beberapa jenis lobster di Teluk Prigi, Kabupaten Trenggalek. Pengambilan sampel isi lambung lobster diperoleh dari hasil tangkapan nelayan lobster di Teluk Prigi, Kabupaten Trenggalek, Provinsi Jawa Timur. Pengumpulan data dilakukan pada Mei dan November 2016. Jumlah sampel lobster yang diamati isi lambungnya berjumlah 63 ekor dengan kisaran panjang karapas 4,6-8,2 mm. Kebiasaan makanan beberapa jenis lobster di Teluk Prigi terdiri dari moluska, krustasea, detritus, karang, tumbuhan (makrofita) dan pasir. Luas relung tertinggi dimiliki oleh lobster bambu (Panulirus versicolor) dan lobster batik (Panulirus longipes).Tumpang tindih relung yang tinggi mengindikasikan tingginya peluang kompetisi dalam memanfaatkan makanan kecuali lobster batik merah (Panulirus longipes femoristriga).

Seaweed is one of the vital export aquaculture commodities in West Java of Indonesia. Since 2013, seaweed production in Muara Gembong Sub-District, especially Pantai Mekar Beach and Pantai Sederhana Villages, can be produced 7.000 tons from total 10.000 seaweed culture fisheries of Bekasi District (80%) that was developed with a polyculture system. To ensure the long-term success of providing seaweed production, evaluation of suitable location is an essential step in any aquaculture operation. This study was conducted to analyze suitable sites for seaweed aquaculture in the coastal area of Muara Gembong based on the condition of water quality. Water quality data were collected from 11 stations during field surveys in March, July, and October 2018. Water quality parameters were observed with physical parameters (Secchi disk transparency, temperature, and depth) and chemical parameters (salinity, pH, DO, phosphate, and nitrate). Evaluation of water quality data included compile of matrix suitability design through some works of literature. The suitability coastal areas were analyzed to get suitable location used GIS software from coordinate data and water quality parameters, which were compared. The class “suitable” has a score of 4, the “suitable enough” class has a score of 3, the “suitable with conditionals” class has a score of 2, and the class “not suitable” has a score of 1. Based on the measurement result, the “suitable” areas were Station 7 (Front of Muara Mati), Station 8 (Outermost Muara Mati), Station 11 (Muara Kuntul), and Station 12 (Front of Muara Kuntul). The coverage area that was in a suitable area category is 962.72 Ha (9.63 km2). The location also linear with the result based on salinity, DO, and transparency (Secchi dish transparency). There are selected locations compared with other stations in Muara Gembong coastal waters because those locations face waste problems from Citarum Watershed and Jakarta Bay. Also, the sites serve as a source of livelihood for the community.

This study carried out on the effect of precursor concentration and annealed substrate temperature on the crystal structure, electronic and optical properties of ZnO thin film. An aqueous solution of Acid Nitrite was used as precursors and its concentration was varied from 0.1 M to 0.4 M. The ZnO thin film was deposited on the glass substrate by Spray Pyrolysis Deposition and annealed with different temperature from 300 oC to 600 oC. The crystal structure, electronic and optical properties were investigated by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and UV-Spectrometer. XRD result showed that all thin films have amorphous hexagonal wurtzite crystalline. Particle sizes ranging from 21.83 to 43.67 nm were calculated through Debye-Scherer Method. It showed that the concentration of the precursor had slightly impact on the particle size. Meanwhile, the increase in particle size with increasing annealed temperature is found to be gradual. The average transparent of all thin film was more than 80%. The bandgap of the ZnO thin films was estimated by Tauc Plot Relation. It showed that the bandgap values were increased with the increasing of precursor concentration due to Burstein-Moss Effect. In addition, the decrease in band gap values was found with increasing annealed temperature. Our results demonstrated that the varying precursor concentration and annealed substrate temperature can enhance the structure, electronic and the optical properties of ZnO thin films.

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Percobaan penebaran lobster pasir (Panulirus homarus) di Perairan Teluk Prigi, Kabupaten Trenggalek dilakukan pada 2015. Percobaan dilakukan dengan cara memberi tanda (tag) pada seluruh sampel lobster pasir yang ditebar, dikenal sebagai metode Capture-mark-recapture (CMR) dan sudah banyak digunakan untuk mempelajari populasi biota di alam. Penelitian bertujuan untuk mengetahui tingkat tertangkap kembali, laju pertumbuhan, dan pergerakan lobster pasir bertanda di Teluk Prigi. Penebaran lobster pasir bertanda dilakukan pada tiga lokasi yaitu Damas, Karanggongso dan Karangasem dengan jumlah 2.784 ekor dan diberi tanda jenis T-bar berwarna merah yang memiliki kode. Pengamatan lobster pasir bertanda yang tertangkap kembali dilakukan sepanjang tahun 2016 di Teluk Prigi (Februari-Desember). Tingkat tertangkap kembali lobster bertanda dihitung menggunakan proporsi antara lobster bertanda yang tertangkap dengan lobster bertanda yang ditebar. Laju pertumbuhan lobster bertanda yang tertangkap kembali dihitung berdasarkan pertumbuhan per satuan waktu yang sama dengan perubahan panjang dibagi dengan perubahan umur. Pergerakan lobster bertanda diukur melalui jarak dari lokasi tebar sampai dengan lokasi lobster bertanda yang tertangkap kembali. Tingkat tertangkap kembali lobster pasir (P. homarus) bertanda di Teluk Prigi sebanyak 4,7 %. Laju pertumbuhan lobster pasir yang tertangkap kembali rata-rata 0,09±0,05 mm/hari. Pergerakan lobster pasir bertanda yang tertangkap kembali di Teluk Prigi berkisar antara 0,1-11,36 km. Pergerakan lobster pasir bertanda memiliki kecenderungan acak dan tetap pada wilayah pantai.In 2015, restocking experiment of Scalloped spiny lobster (Panulirus homarus) was conducted in Gulf of Prigi, Trenggalek Regency and the  lobsters were tagged. This methods is known as Capture-mark-recapture (CMR). CMR is widely used to study of biota populations in wild nature. The aims of this study are to determine the recapture rate, growth rate, and movement of tagged scalloped spiny lobster in Prigi Bay.The tagged spiny lobster release was realesed at three locations, namely Damas, Karanggongso and Karangasem with 2,784 lobsters and was tagged with a red T-bar type that has a code. Observations of tagged scalloped spiny lobsters were carried out again throughout 2016 in Prigi Bay (February-December). The recapture rate of tagged spiny lobster is calculated using the proportion between the tagged lobster with the tagged lobster released. The tagged tagged spiny lobster growth rate is calculated again based on growth per unit time which is equal to the change in length divided by the change in age. Tagged spiny lobster movements are measured by distance from the location of release to the location of the tagged tagged spiny lobster is capture again. The recapture rate of tagged spiny lobster (P. homarus) marked in Gulf of Prigi as much as 4.7%. The growth rate of tagged spiny lobster averaged 0.09 ± 0.05 mm/day. The movement of tagged spiny lobster in Gulf of Prigi ranges from 0.1 to 11.36 km. The movement of tagged spiny lobster has a random movement  and remains in the coastal region.

Danau Beratan yang terletak di kawasan Bedugul, Bali telah terintroduksiikan zebra cichlid (Amatitlania nigrofasciata Günther, 1867) secara tidak sengaja. Tujuan penelitian adalah untuk mengetahui potensi ikan zebra sebagai ikan asing invasif di Danau Beratan berdasarkan kajian pada beberapa aspek biologinya. Penelitian dilakukan dengan metode survei lapang di Danau Beratan, Bali pada bulan Mei, Juli dan Oktober 2011. Contoh ikan diperoleh menggunakan jaring insang percobaan dan jaring tarik. Analisis data meliputi hubungan panjang berat, faktor kondisi, parameter pertumbuhan, kebiasaan makanan dan aspek reproduksi ikan. Hasil penelitian menunjukkan ikan zebra mendominasi hasil penangkapan. Ikan tersebut memiliki faktor kondisi yang baik dengan nilai laju pertumbuhan tahunan (K) yang tinggi, bersifat generalis dalam memanfaatkan sumber daya makanan dan matang gonad pada ukuran panjang yang kecil. Karakteristik biologi inimengindikasikan ikan tersebut memiliki potensi invasif yang cukup tinggi. Lake Beratanislocated inBedugul, Balihas been an unintentional introduction ofzebracichlid(Amatitlania nigrofasciataGünther, 1867). The aim of this research was to determine thepotential ofzebra cichlid becomeinvasivealienfish speciesinLake Beratanbasedonseveralbiological aspects.The study was carried outby field surveymethods in Lake Beratan, Bali on May, JulyandOctober 2011. Fish samples was obtained usingexperimentalgillnetsandmodification ofseine nets. Data analysis included the lengthweightrelationship, conditionfactor, growth parameters, foodhabitsand its reproduction aspects. The results showedthat zebracichliddominatethe experimental catchin LakeBeratan. Analysis showedthese fishhavea goodconditionwith ahigh growth rate, have a generalist characteristic in exploitingthe natural food resourcesandmatureat small length size. A reviewforseveral biological aspects ofthe zebra cichlidshowedthatfishhavea highinvasivepotentialinLake Beratan.