Judul: Utilization Status of Scalloped Spiny Lobster (Panulirus homarus) in Coastal Waters Ayah Kebumen
Abstrak: Keberlanjutan menjadi salah satu isu penting dalam pemanfaatan sumberdaya lobster. Ketersediaan data menjadi faktor pembatas untuk mengetahui status pemanfaatan lobster khususnya lobster yang dominan ditemukan di Perairan Pantai Ayah, Kabupaten Kebumen yaitu lobster pasir (Panulirus homarus). Pendekatan length base spawning potential ratio (LB-SPR) digunakan untuk menentukan status pemanfaatan lobster. Penelitian ini bertujuan mendeskripsikan unit penangkapan lobster, mengidentifikasi komposisi ukuran hasil tangkapan lobster, dan menghitung parameter biologi lobster untuk mengetahui status pemanfaatan lobster pasir (Panulirus homarus). Data ukuran panjang karapas lobster dikumpulkan dengan metode accidental sampling. Analisis yang digunakan yaitu analisis deskriptif, analisis pertumbuhan, mortalitas, laju eksploitasi, pola rekruitmen dan spawning potential ratio. Hasil penelitian menunjukkan bahwa, panjang asimptotik lobster pasir jantan dan betina sebesar 120,75 mm dan 120,11 mm. Nilai koefisien pertumbuhan lobster pasir jantan dan betina yaitu sebesar 0,47 dan 0,40 per tahun. Nilai laju mortalitas baik lobster pasir jantan dan betina yaitu 0,75 dan 0,68 per tahun. Laju eksploitasi lobster pasir jantan dan betina sebesar 0,46 dan 0,38. Rata-rata ukuran panjang karapas lobster pasir yang tertangkap sebesar 79,37 mm termasuk dalam ukuran sudah layak tangkap. Status pemanfaatan lobster pasir (Panulirus homarus) di perairan Pantai Ayah Kabupaten Kebumen sebesar 36% yang artinya lestari., Sustainability is an important issue in the utilization of lobster resources. However, the availability of data is a limiting factor to determine the status of lobster utilization. Scalloped spiny lobster (Panulirus homarus) is dominantly found in the Ayah Coastal Waters, Kebumen Regency. The length base spawning potential ratio (LB-SPR) used to determine the status of lobster utilization. This study aims to describe lobster fishing units, to identify the size composition of lobster catches, and to calculate lobster biological parameters for determining the utilization status of Panulirus homarus. Length data of lobster carapace were collected by accidental sampling method. The research were applied descriptive analysis, analysis of growth, mortality, exploitation rate, recruitment pattern and spawning potential ratio. The results showed that there was a asymptotic lengths of male and female Panulirus homarus by 120,75 mm and 120,11 mm, respectively. In addition, the growth coefficient value of male and female Panulirus homarus was 0,47 and 0,40 per year. Furthermore, the mortality rate values for both male and female lobster were 0,75 and 0.68 per year; the exploitation rate of male and female was 0,46 and 0,38. Moreover the average carapace length caught of them were 79,37 mm, which was included in the legal size for catching. These result found that the utilization status of Panulirus homarus in the Ayah Coastal Waters, Kebumen Regency was 36%, which means fully moderate.
Keyword: Scalloped Spiny Lobster, Kebumen waters, Panulirus homarus, spawning potential ratio (SPR), utilization status

Judul: Dinamika Populasi Lobster Pasir (Panulirus homarus) Dan Lobster Batu (Panulirus penicillatus) Di Perairan Selatan Jawa Barat
Abstrak: Lobster merupakan komoditas penting baik impor maupun ekspor. Permintaan pasar yang tinggi menyebabkan laju penangkapan tinggi sehingga mempengaruhi penurunan populasi. Penelitian ini bertujuan mengkaji status populasi lobster di perairan Selatan Jawa Barat berdasarkan pendugaan parameter dinamika populasi. Pengambilan sampel menggunakan metode penarikan contoh acak sederhana selama bulan Februari hingga Juni 2023. Ukuran panjang karapas lobster berkisar 30-182 mm dengan pola pertumbuhan allometrik negatif. Rekruitmen terjadi sepanjang tahun dengan satu puncak. Ukuran pertama kali tertangkap (Lc50) lobster pasir jantan pada panjang karapas 46,36 mm dan betina pada 49,65 mm, lobster batu jantan pada panjang karapas 50,69 mm dan betina pada 58,82 mm. Ukuran pertama kali mengerami telur (Lr50) lobster pasir betina pada panjang karapas 69,95 mm dan lobster batu betina pada 79,94 mm. Laju eksploitasi lobster betina termasuk kategori optimum dan jantan termasuk kategori overexploited. Rasio potensi pemijahan (SPR) lobster pasir dan batu betina berturut-turut sebesar 12% dan 4% yang mengindikasikan bahwa sumberdaya lobster telah mengalami overfishing., Lobster is an important commodity for both import and export. High market demand causes high capture rates that affect population decline. This study aims to assess the status of the lobster population in the southern waters of West Java based on the estimation of population dynamics parameters. Sampling used a simple random sampling method from February to June 2023. Lobster carapace length ranged from 30-182 mm with a negative allometric growth pattern. Recruitment occurred throughout the year with one peak. First caught size (Lc50) of male sand lobster at 46.36 mm carapace length and female at 49.65 mm, male rock lobster at 50.69 mm carapace length and female at 58.82 mm. The size of the first incubating egg (Lr50) of female sand lobster at 69.95 mm carapace length and female rock lobster at 79.94 mm. The exploitation rate of female lobsters is in the optimum category and males are in the overexploited category. The spawning potential ratios (SPR) of female sand and rock lobsters were 12% and 4%, respectively, indicating that the lobster resource has been overfishing.
Keyword: population dynamics, pronghorn spiny lobster, scalloped spiny lobster, Southern waters of West Java, sustainable

Judul: Elektrodeposisi Film Tipis Semikonduktor Cu2ZnSnS4 (CZTS) pada Substrat Kaca ITO
Abstrak: Semiconductor Cu2ZnSnS4 (CZTS) thin film that can be used as absorber layers on solar cell module was made via electrodeposition method. CZTS thin film was electrodeposited on the surface of a silicate glass coated with a thin layer of indium tin oxide (ITO). Deposition process was done using potentiostatic mode at room temperature with a potential of 1.05 V for 30, 45, and 60 minutes, followed with annealing the film at 2 different temperatures, 500 ºC using furnace and 180 ºC using hot plate, both treatments for 45 minutes in N2/H2S atmosphere. The X-ray difractograms were analyzed using Match 2 program and showed that the CZTS thin films had kesterit crystalline structure, with a low percentage of CZTS phase. The thin film also contained secondary phases such as Cu2S, ZnS, and SnS. The obtained CZTS thin films had a thickness between 1.039 and 1.676 μm. Absorption study showed that the band gap energy of CZTS thin films which was annealed using furnace ranged from 1.50 to 1.52 eV, whereas that annealed using the hot plate was not observed. The band gap energy value showed that CZTS thin films can be used as sunlight absorber layers on solar cell. The formation of CZTS crystal film on this investigation was effectively performed using furnace annealing process at a temperature of 500 ºC with deposition time of 45 minutes.
Keyword: Thin film, Electrodeposition, Cu2ZnSnS4