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Journal : Jurnal Perikanan Universitas Gadjah Mada

POLA SEBARAN HORIZONTAL DAN KERAPATAN PLANKTON Di PERAIRAN BAWEAN Djumanto Djumanto; Tumpak Sidabutar; Hanny Pontororing; Reinhard Leipary
Jurnal Perikanan Universitas Gadjah Mada Vol 11, No 1 (2009)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1174.22 KB) | DOI: 10.22146/jfs.3028

Abstract

The objectives of this research were to find out the horizontal distribution patterns, the density and species dominancy of plankton in Bawean waters, Gresik regency. Sampling was done using RV Baruna Jaya VIII on 29-30 April 2009. There were 12 stations for sampling, which arranged latitude 3 stations to the north and longitude 4 stations to the east with the distance of 8 and 12 miles, respectively. Water samples were collected using Kitahara net for phytoplankton and Norpac net for zooplankton by filtering from bottom to surface. The density of plankton for each station was measured base on their biovolume bases, namely settlement for phytoplankton whereas water replacement for zooplankton. Genus of plankton was identified for each station.The results showed that the highest density of phytoplankton was found in the northern part and was decreased towards the south, while the highest zooplankton was found in the middle area. The density of phytoplankton was distributed homogeneously, while zooplankton was distributed randomly. The density of biomass phytoplankton ranged from 0.294-3.985 ml/rn3 and an average wasl.598 ml/m3. The density of biomass zooplankton ranged from 0.05-0.24 ml/m3, and an average was 0.122 ml/m3. The ratio of biovolume between phytoplankton and zooplankton ranged from 3:1-31:1 with an average was 13:1. The individual density of phytoplankton ranged from 15,843 - 1,755,694 individual/m3, while zooplankton was between 861-29,362 individual/m3. In the phytoplankton was found as much as 34 genus, and there were 5 genus which their populations were abundantly, namely Caetoceros, Skeletonema, Rizosolenia, Pleurosigma and bacteriostratum with percentage of 25,34%, 24,45%, 13,84%, 10,68% and 8,10%, respectively. The biology index of phytoplankton, namely diversity (H) ranged from 1.11-2.22, uniformities (E) ranged from 0.50- 1.00, and dominancy (D) ranged from 0.16 - 0.50. in the zooplankton was found 65 genus, and there were 5 genus of their populations was abundantly, that was Ceratium, Calanus, Cetocerelia, Agalma and Fritillaria with percentage 22.26%, 17.10%, 6.96%, 6.92% and 5.21%, respectively. The diversity index of zooplankton ranged from 1.83 - 2.56, uniformities ranged from 0.791.00, and dominancy ranged from 0.12-0.23. The population forming of phytoplankton and zooplankton were very assorted and dynamic.
PEMBENIHAN NILA MERAH (Oreochromis sp.) MENGGUNAKAN JARING APUNG DI WADUK KEDUNGOMBO Rustadi Rustadi; Djumanto Djumanto; Bambang Triyatmo; Ign. Hardaningsih; Hery Saksono
Jurnal Perikanan Universitas Gadjah Mada Vol 1, No 1 (1996)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jfs.8852

Abstract

The objectives of the research were to know the production of hatchery, survival rate and growth rate of fry. Floating nets  were made for plastics hapa (2 mm mesh size) with 3 different size (5 m2, 10 m2, and 15 m2). The larvae were stocked in different hapa nursery size ( 1 m3, 2 m3, 3 m3) at the rate of 1000 larvae/m3 of water. The fry produced from the first nursery were subsequently reared in waring (mesh size 0,04 cm) at density of 600 fry/m3 of water. The spawning were conducted for 6 months, while larvae rearing were 2 months for each period respectively. The result showed that the hatchery of 15 m2 scale were technically and biologically feasible. During 6 months period it produced 11,870 fingerling of 40 gram, 3,028 fry of 4 gram and 4,290 of larvae. The survival rate and growth rate of fry water not significantly affected by different hapa size either in the first and second nursery. The survival rate of the first nursery was 64.70-72.63% of 5.0-6.8 cm fry, while the second nursery was 97.29-98.30% of 11.5-12.4 cm fry. 
REPRODUCTIVE BIOLOGY OF THE YELLOW RASBORA (Rasbora lateristriata) INHABITAT OF THE NGRANCAH RIVER, KULON PROGO REGENCY Djumanto Djumanto; Eko Setyobudi; A. A. Sentosa; N. Nirwati
Jurnal Perikanan Universitas Gadjah Mada Vol 10, No 2 (2008)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jfs.8904

Abstract

The purpose of this research was to identify the reproductive biology in the yellow rasbora (Rasbora lateristriata) in habitat of the Ngrancah River. To identify spawning events and embryo development, direct observation was employed during the spawning season in their natural environment, and then fertilized egg was incubated insitu. Spawning seasons underwent correspond to the end of rainy season and early dry season which characterized by clean freshly water and low temperature. The result showed that during spawning season, the broodfish migrated from Sermo Reservoir upward to the main river to find out the spawning site. In the early morning between 03.00 and 05.00 AM, the broodstock moved to the spawning site, then making aggregation and both female and male released their gametes in the shallower place. The aggregations were consisting around of 1 female and 3 males. The fertilized eggs would cleavage, and then embryo developed and yolk sac larval hatched within 23 hours at 27oC. The knowledge about spawning events of yellow rasbora may be used for improved management tools in the future.
PEMANFAATAN DAN LAJU TANGKAP UDANG LOBSTER DI PANTAI SELATAN DAERAH ISTIMEWA YOGYAKARTA Supardjo S Djasmani; Djumanto Djumanto; Sukardi Sukardi
Jurnal Perikanan Universitas Gadjah Mada Vol 14, No 1 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jfs.9051

Abstract

Penelitian ini bertujuan untuk mengetahui potensi sumberdaya lobster, laju tangkap dan peluang pengembangannya. Metode penelitian yang digunakan dalam pengumpulan data adalah metode survei. Data dianalisis dengan metode surplus produksi metode Schaefer. Hasil penelitian menunjukkan lobster yang ada di pantai selatan DIY sebagian besar dari jenis udang pasir (Panulirus homarus), udang batu (Panulirus penisilatus), udang mutiara (Panulirus ornatus), udang bambu (Panulirus polyphagus) dan udang batik (Panulirus longipes). Produksi udang lobster berfl uktuatif baik secara musim dan tahunan dengan musim panen mulai bulan Oktober sampai dengan bulan Februari dan produksi tertinggi pada tahun 2007. Analisis mengenai jumlah perahu optimum foptimum adalah 723 unit perahu/th dengan potensi lestari maksimum (CMSY) sebesar 12.322,66 kg/th dan tangkapan total yang diperbolehkan (TAC) adalah 9.858,13 kg/th sedangkan aktual tingkat pemanfaatan sebesar 10.721,42 kg/th dengan laju tangkap adalah 17,05 kg/perahu/tahun. Upaya jumlah trip optimum diperoleh f(optimum) 13.324,39 trip/th dengan potensi maksimum lestari (CMSY) sebesar 13.914,6 kg/trip dan hasil tangkapan total yang diperbolehkan (TAC) adalah 11.136,7 kg/th, sedangkan aktual tingkat pemanfaatan mencapai 11.859,2 kg/th dengan laju tangkap pemanfaatan lobster sebesar 1,04 kg/trip. Hasil penelitian menunjukkan bahwa tingkat pemanfaatan sumberdaya lobster sudah lebih besar dari pada tangkapan total yang diperbolehkan (TAC) dan mendekati potensi lestari maksimum (MSY).
INDEK BIOTIK FAMILI SEBAGAI INDIKATOR KUALITAS AIR SUNGAI GAJAHWONG YOGYAKARTA Djumanto Djumanto; Namastra Probosunu; Rudy Ifriansyah
Jurnal Perikanan Universitas Gadjah Mada Vol 15, No 1 (2013)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jfs.9095

Abstract

The purpose of this research was to determine water quality level of Gajahwong River, Yogyakarta with the present of macroinvertebrate as biologycal indicators. The sampling was conducted in the Gajahwong River fl ow from Pakem subdistrict in Sleman regency to Pleret subdistrict in Bantul regency. There were six sampling stations, and sampling was conducted once a week for two months from mid October to December 2011. Samples of macroinvertebrate were collected by poking substrate in front of surber net mouth so that macroinverterbrate were drifted into surber and trapped in pocket net. Samples were preserved in 5% formaldehide solution then identifi catifi ed and anlyzed in the laboratory.The species number of macroinvertebrate were analyzed as biotic index, such as diversity index, evenness index, dominance index and biotic family index (BFI). Environment parameter measured include physical and chemical properties. The physical parameter collectednamely subtrate type, river depth and stream width, fl ow velocity, temperature and total suspended solid (TSS). The chemical parameter collected namely dissolved oxygen, free CO2, alcalinity,organic matter and pH. The results showed that fl ow rate was varied 0.51-0.80 m/det decrease to downstream direction.The water depth was ranging from 19.9 to 49.8 cm tend to increase downstream direction. Total suspended solid (TSS) was ranging from 8.5 to 14.2 mg/l and tend to be higher in the central city of Yogyakarta. Dissolved oxygen concentration was 6.0-7.2 mg/l while CO2 was 0.7-1.9 mg/l. Organic matter was 22.8-25.1 mg/l and pH was in the range of neutral. The density of macroinvertebrate was 88 individual/m2, the taxa number in each station was 7-12 species, diversity index was 1.48-2.09, evenness index 0.76-0.85 and dominance index was 0.10-0.27, and there was not found dominance organism among the stations samplings. The highest density was Limnaea tranculata and Potamopyrgus jenkinsi. Index biotic family ranging from 5.95 to 6.64 showing the water environment was poor and there has been pollution caused by garbage disposal of communities surround the river also waste disposal from resident along the watershed.
Komunitas Krustasea di Kawasan Mangrove Desa Jangkaran Kabupaten Kulon Progo Sholihat Amalia; Djumanto Djumanto; Namastra Probosunu
Jurnal Perikanan Universitas Gadjah Mada Vol 19, No 2 (2017)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jfs.26968

Abstract

The objective of this study was to determine the diversity and abundance of krustaseans in the mangrove area of Jangkaran Village, Temon District, Kulon Progo Regency. Sampling was done bi-weekly from October 2016 to February 2017 on six stations defined by ecological character. Krustasean sampling was done using cest net, trap net and hand picking along the river with the extent of each collection station about 10 m2. The captured krustasean samples were cleaned, stored in ice-cooled boxes and transported to the laboratories to be identified and grouped according to species, then measured by carapace length and individual weight. Observation of aquatic environment was done by measuring temperature, brightness, water depth, current velocity, pH, salinity, dissolved oxygen, and substrate type. The results of the observation obtained 1 order, 7 families, and 26 species. The family krustaseans found were Coenobitidae, Diogenidae, Grapsidae, Ocypodidae, Palaemonoidae, Penaeidae, and Portunidae. The most dominant species of krustaseans were white shrimp (Penaeus merguiensis) as much as 25.06%, hermit crab (Clibanarius sp.) as much as 10.85%, and Uca annulipes as much as 10.59%. The fewest species of krustaseans found were Varuna yui of 0.13% and Ocypode sp. as much as 0.26%. The abundance value was 25.4 ind / m2, indices of diversity 2.60, richess index 0.87 and index of dominance 0.18.
Preferences of Giant Gouramy (Osphronemus gouramy, Lac, 1801.), Walking Catfish (Clarias sp.) and Red Nile (Oreochromis sp.) on Natural Feed in Fish Culture Dea Nafila; Rustadi Rustadi; Djumanto Djumanto
Jurnal Perikanan Universitas Gadjah Mada Vol 20, No 2 (2018)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (671.262 KB) | DOI: 10.22146/jfs.34494

Abstract

The aim of this study was to determine the preference for plankton as natural feed by giant gourami, walking catfish, and red nile on intensive aquaculture system. The study was designed using Completely Randomized Design (RAL), with two replications. Each fish was kept in six concrete tanks with dimension 2x2x1 m³ and 60 cm water level. Water source were from wells. Commercial pellet feed was given in three times daily ad libitum. Water samples were filtered and two individual fish were collected for plankton samples from pond water and alimentary canal, respectively, every two week, simultaneously with water quality measurements. Plankton samples were preserved using 5% formaldehyde and was observed under a compound light microscope with 100x magnification. The amount of plankton in the alimentary canal was converted to volume. Data were analyzed descriptively. The result showed that the volume contents proportion of plankton in the alimentary canal was less than 1%. The volume of plankton proportion in the alimentary canal of red nile were found the most than other fish. Each fish had the same preference of plankton of Lepocinclis and Scenedesmus, but different from other species of plankton. The plankton that utilized by giant gouramy were Crucigenia, Diadesmis and Navicula, whereas walking catfish was Pediastrum, and red nile was Microcystis. The plankton that preferred by giant gouramy were Crucigenia, Oscillatoria, Splirullina, and Synedra, walking catfish was Navicula, while red nile were Chrysamoeba and Tintinnidium.
Reproduction of Indian Mackerel Rastreliger kanagurta (Cuvier, 1816) in Morodemak Coast Demak Regency Dwi Rachmanto; Djumanto Djumanto; Eko Setyobudi
Jurnal Perikanan Universitas Gadjah Mada Vol 22, No 2 (2020)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jfs.48440

Abstract

Indian mackerel is a group of small pelagic fish that has high economic value and is ecologically important. The catch of Indian mackerel in the Morodemak Coastal Fishing Port of Central Java has decreased within 2016-2018, which is suspected by overexploitation. This study aims to observe the reproduction of Indian mackerel. Fish samples were collected from the catches of the mini purse seine operated by fishermen in April-June 2019. The fish samples were measured their length and weight individually, then the abdomen dissected to collect gonad, and counted in sub-sample of the egg number. Data were analyzed to determine the length-weight relationship of fish, sex ratio, gonad maturity level (GML), gonad maturity index (GMI), the size of the first gonad matured, and the egg number in each gonad brood fish. The results showed a negative allometric length relationship, and the length-weight relation equation in female fish was W = 0.038 L 2.59 and in male was W = 0.178 L 2.03. The value of fish condition factors in males, and females obtained values ranging from 1-2. The proportion of fish in GML III ranges from 27.2 to 82.5%, while GML IV ranges from 3.6 to 33.8%. Fish GMI ranged from 0.17 to 4.75%. The eggs number ranged from 11.235 to 40.878 grain. The female Indian mackerel get the first gonad matured at the size of 15.2 cm.