scholarly journals POLA SEBARAN IKAN PADA MUSIM BARAT DAN PERALIHAN DI PERAIRAN UTARA JAWA TENGAH

2017 ◽  
Vol 14 (1) ◽  
pp. 67
Author(s):  
Asep Priatna ◽  
Mohammad Natsir
Keyword(s):  
Food Source ◽  
Target Strength ◽  
Fish Density ◽  
Current Direction ◽  
North West ◽  
Pelagic Fishes ◽  
Central Java ◽  
The Difference ◽  
West Monsoon ◽  
Demersal Fishes

Penelitian ini bertujuan untuk mempelajari perbedaan pola sebaran ikan pada musim barat dan peralihan di perairan utara Semarang sampai dengan Brebes, berdasarkan pada pengambilan contoh akustik dan oseanografi pada bulan Desember 2005 dan Mei 2006. Hasil menunjukkan secara spasial, pada musim barat di perairan utara Semarang sampai dengan Brebes kepadatan ikan pelagis lebih besar di daerah yang lebih dangkal yaitu sebelah selatan pada kedalaman <40 m, semakin ke tengah kepadatan semakin berkurang. Dilihat dari nilai target strength yang terdeteksi yaitu antara -60 sampai dengan -50 dB bahkan didominasi oleh ikan -60 sampai dengan -55 dB, sasaran merupakan ikan pelagis kecil yang rata-rata mempunyai ukuran 4 sampai dengan 12,5 cm. Pada musim peralihan sebaran kepadatan ikan pelagis kecil cenderung lebih merata dengan jumlah yang lebih rendah daripada jumlah ikan pada musim barat. Faktor pergerakan arah arus dan keberadaan sumber makanan yang lebih besar pada musim barat diduga merupakan penyebab perbedaan tersebut. Ikan pelagis kecil pada musim peralihan berukuran lebih besar dibandingkan ketika musim barat, dengan nilai target strength yang terdeteksi antara -60 sampai dengan -45 dB atau sekitar 4 sampai dengan 22 cm dan didominasi oleh ikan yang berukuran -55 sampai dengan -50 dB atau sekitar 7 sampai dengan 12,5 cm. Sebaran kepadatan Ikan demersal hampir merata pada ke-2 musim tersebut, pada musim peralihan kepadatan lebih rendah daripada musim barat. Ikan demersal pada musim barat terdiri atas ikan berukuran kecil (-55 sampai dengan -50 dB) atau sekitar 7 sampai dengan 12,5 cm terutama di daerah pada kedalaman <40 m, semakin ke tengah ukuran semakin besar yaitu antara -50 sampai dengan -45 dB atau sekitar 12,5 sampai dengan 22 cm. Pada musim peralihan, ikan demersal dengan target strength -55 sampai dengan -50 dB terdapat di kedalaman <40 m. Ikan demersal dengan ukuran -50 sampai dengan -45 dB mendominasi periode ini. Pada kedalaman >45 m terdeteksi ikan -45 sampai dengan -35 dB yang berkisar 22 sampai dengan 70 cm. The aim of this study is to understood the difference of fish pattern distributions at North West and intermonsoon in North of Central Java waters, based on acoustic and oceanography sampling in December 2005 and May 2006. At North West monsoon, the density of pelagic fishes was more gathering in narrower areas <40 m, and low fish density was going to middle areas. Seen from target strength the value was detected about -60 to -50 dB and it was dominated by fishes -60 to -55 dB, the targets for small pelagic fishes are about 4 to 12,5 cm. At the intermonsoon, distribution of small pelagic fishes density tends to be flat, but fish density at this time was the lower than North West monsoon. The higly current direction and food source factor at North West monsoon may cause this difference. The size of small pelagic fishes at the intermonsoon was bigger than fishes at North West monsoon, which target strength value was detected about -60 to -45 dB or 4 to 22 cm and dominated by fishes -55 to -50 dB of about 7 to 12,5 cm. The density distribution of demersal fishes almost flat at both monsoon. How ever at intermonsoon, the demersal fishes density was lower than that at North and West season. Demersal fishes at North West monsoon consisted of small fishes (-55 to -50 dB) with size of about 7 to 12,5 cm especially in narrow areas <40 m, and fish sizes the larger (-50 to -45 dB or 12,5 to 22 cm) were going to the middle areas. At intermonsoon, there were demersal fishes with target strength -55 to -50 dB at <40 m. Demersal fishes with target strength -55 to -50 dB were dominant at this time. At areas >45 m it was detected fishes of -45 to -35 dB target strength of about 22 to 70 cm.

scholarly journals DISTRIBUSI KEPADATAN IKAN PELAGIS DI PERAIRAN PANTAI UTARA JAWA BAGIAN TIMUR, PULAU-PULAU SUNDA, DAN LAUT FLORES

2017 ◽  
Vol 13 (3) ◽  
pp. 223
Author(s):  
Asep Priatna ◽  
Mohammad Natsir
Keyword(s):  
Environmental Factor ◽  
Pelagic Fish ◽  
Target Strength ◽  
Fish Density ◽  
Small Pelagic Fish ◽  
Pelagic Fishes ◽  
East Region ◽  
Marginal Areas ◽  
Near Shore ◽  
Distribution Of Fish

Penelitian ini bertujuan untuk mempelajari distribusi spasial kepadatan ikan pelagis serta hubungan dengan kondisi perairan pada musim peralihan di perairan pantai utara Jawa bagian timur dan Laut Flores, berdasarkan pada pengambilan contoh akustik dan 34 stasiun oseanografi pada bulan Oktober 2005. Data target strength menunjukkan bahwa rata-rata ukuran ikan pelagis yang terdeteksi di perairan pantai utara Jawa bagian timur adalah 10 sampai dengan 56 cm. Ukuran ikan di daerah lepas pantai lebih kecil dibanding daerah dekat pantai. Pada musim peralihan, kondisi suhu dan salinitas perairan relatif homogen. Sehingga faktor tersebut kurang signifikan terhadap distribusi keberadaan ikan. Diduga faktor lingkungan lain seperti faktor biologi dan kimia, berperan dalam pola penyebaran ikan pelagis kecil di perairan ini. Di Laut Flores dan sekitar Pulau-Pulau Sunda, densitas ikan tertinggi pada stratum 10 sampai dengan 50 m dengan ukuran 10 sampai dengan 20 cm terutama di beberapa lahan marginal seperti sekitar selat dan kepulauan. Selain merupakan lapisan tercampur di mana kondisi suhu dan salinitas relatif stabil pada kedalaman 10 sampai dengan 50 m, lahan marginal merupakan daerah subur tempat pertemuan 2 massa air yang berbeda yang membentuk front diharapkan merupakan tempat berkumpul ikan. Lapisan termoklin yang bersifat lemah berada di bawah 50 m, hal ini mempengaruhi densitas ikan yang semakin rendah pada kedalaman lebih dari 50 m. Ikan pelagis yang berada pada lapisan termoklin mempunyai ukuran yang lebih besar yaitu 14 sampai dengan 40 cm. Pada musim yang sama, rata-rata kepadatan dan ukuran ikan pelagis kecil di wilayah timur lebih rendah daripada sebelah barat. The aim of this research is to study the distribution of spasial density of pelagic fish with waters condition at intermonsoon in north of Java coast waters part of east and Flores Sea, based on acoustic sampling and 34 oceanography stations in October 2005. The target strength of fish indicated that pelagic fish measure in north of Java coast waters part of east is about 10 to 56 cm. Fish sizes in offshore is smaller than near shore. At intermonsoon, the waters condition of temperature and salinity was homogeneous relatively. Therefore, that are less to distribution of fish density. Anticipated, the others environmental factor like chemical and biological, was influenced to distribution of small pelagic fish in this area. In Flores Sea and Sunda Islands, the highest of fish density at 10 to 50 m and fish sizes about 10 to 20 cm especially in some marginal areas near archipelago and strait. At 10 to 50 m is mixed layer, where temperature and salinity was relative stabilize, the maginal areas is fertility waters which is passage of the shifting by two different water masses and front were formed . The weak termocline was formed below 50 m, maked fish density are progressively lower below 50 m. The pelagic fish residing in termocline layers have larger ones measure than stratum 10 to 50 m is about 14 to 40 cm. On same season, the fish measure and density of small pelagic fishes in east region is lower than at westside.

Numerical Model of Current Speed in Bojong Salawe Beach, Pangandaran West Java Province

2021 ◽  
Vol 2 (1) ◽  
pp. 17-23
Author(s):  
Subiyanto Subiyanto ◽  
Nira na Nirwa ◽  
Yuniarti Yuniarti ◽  
Yudi Nurul Ihsan ◽  
Eddy Afrianto
Keyword(s):  
Numerical Models ◽  
High Tide ◽  
Movement Pattern ◽  
Numerical Data ◽  
Current Speed ◽  
The West ◽  
Instantaneous Speed ◽  
The Difference ◽  
West Monsoon ◽  
Current Movement

The purpose of this study was to determine the hydrodynamic conditions at Bojong Salawe beach. The method used in this research is a quantitative method, where numerical data is collected to support the formation of numerical models such as wind, bathymetry, and tide data. The hydrodynamic model will be made using Mike 21 with the Flow Model FM module to determine the current movement pattern based on the data used. In the west monsoon with a maximum instantaneous speed of 0.04 - 0.08 m/s, while in the east monsoon it moves with a maximum instantaneous speed of 0,4 – 0,44 m/s. The dominant direction of current movement tends to the northeast. The results indicate the current speed during the east monsoon is higher than the west monsoon. The difference in the current speed is also influenced by the tide conditions; higher during high tide and lower during low tide. Monsoons also have a role in the current movements, though the effect is not very significant.

United Front: Partisans of the Leningrad Region and their connections with the Central Asian Soviet Republics

2021 ◽  
Vol 2021 (02) ◽  
pp. 214-225
Author(s):  
Sergey Kulik ◽  
Аnatoliy Kashevarov ◽  
Zamira Ishankhodjaeva
Keyword(s):  
World War Ii ◽  
Weather Conditions ◽  
Leningrad Region ◽  
World War ◽  
North West ◽  
The North ◽  
Occupied Territory ◽  
Central Asian ◽  
The Difference ◽  
Almost All

During World War II, representatives of almost all the Soviet Republics fought in partisan detachments in the occupied territory of the Leningrad Region. Among them were many representatives of the Central Asian republics: Kazakhstan, Kyrgyzstan and Uzbekistan. Many Leningrad citizens, including relatives of partisans, had been evacuated to Central Asia by that time. However, representatives of Asian workers’ collectives came to meet with the partisans. The huge distance, the difference in cultures and even completely different weather conditions did not become an obstacle to those patriots-Turkestanis who joined the resistance forces in the North-West of Russia.

scholarly journals Molecular gas in the northern nucleus of Mrk 273: Physical and chemical properties of the disc and its outflow

2018 ◽  
Vol 617 ◽  
pp. A20 ◽  
Author(s):  
R. Aladro ◽  
S. König ◽  
S. Aalto ◽  
E. González-Alfonso ◽  
N. Falstad ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Far Infrared ◽  
Molecular Gas ◽  
Dense Gas ◽  
Dynamical Mass ◽  
North West ◽  
North East ◽  
Dust Temperature ◽  
The Difference ◽  
Physical And Chemical

Aiming to characterise the properties of the molecular gas in the ultra-luminous infrared galaxy Mrk 273 and its outflow, we used the NOEMA interferometer to image the dense-gas molecular tracers HCN, HCO+, HNC, HOC+ and HC3N at ∼86 GHz and ∼256 GHz with angular resolutions of 4ʺ̣9 × 4ʺ̣5 (∼3.7 × 3.4 kpc) and 0ʺ̣61 × 0ʺ̣55 (∼460 × 420 pc). We also modelled the flux of several H2O lines observed with Herschel using a radiative transfer code that includes excitation by collisions and far-infrared photons. The disc of the Mrk 273 north nucleus has two components with decoupled kinematics. The gas in the outer parts (R ∼ 1.5 kpc) rotates with a south-east to north-west direction, while in the inner disc (R ∼ 300 pc) follows a north-east to south-west rotation. The central 300 pc, which hosts a compact starburst region, is filled with dense and warm gas, and contains a dynamical mass of (4 −5) × 109 M⊙, a luminosity of L′HCN = (3–4) × 108 K km s−1 pc2, and a dust temperature of 55 K. At the very centre, a compact core with R ∼ 50 pc has a luminosity of LIR = 4 × 1011 L⊙ (30% of the total infrared luminosity), and a dust temperature of 95 K. The core is expanding at low velocities ∼50–100 km s−1, probably affected by the outflowing gas. We detect the blue-shifted component of the outflow, while the red-shifted counterpart remains undetected in our data. Its cold and dense phase reaches fast velocities up to ∼1000 km s−1, while the warm outflowing gas has more moderate maximum velocities of ∼600 km s−1. The outflow is compact, being detected as far as 460 pc from the centre in the northern direction, and has a mass of dense gas ≤8 × 108 M⊙. The difference between the position angles of the inner disc (∼70°) and the outflow (∼10°) indicates that the outflow is likely powered by the AGN, and not by the starburst. Regarding the chemistry in Mrk 273, we measure an extremely low HCO+/HOC+ ratio of 10 ± 5 in the inner disc of Mrk 273.

scholarly journals Prevalence and diversity of ectoparasites in scavenging chickens (Gallus domesticus) and their association to body weight

2020 ◽  
Vol 21 (7) ◽  
Author(s):  
Edy Riwidiharso ◽  
Darsono Darsono ◽  
Endang ariyani Setyowati ◽  
Hery Pratiknyo ◽  
EMING SUDIANA ◽  
...  
Keyword(s):  
Body Weight ◽  
Rural Areas ◽  
Gallus Domesticus ◽  
Survey Method ◽  
Central Java ◽  
The Common ◽  
The Difference ◽  
The Relationship ◽  
The City ◽  
Regression Correlation

Abstract. Riwidiharso E, Darsono, Setyowati EA, Pratiknyo H, Sudiana E, Santoso S, Yani E, Widhiono I. 2020. Prevalence and diversity of ectoparasites in scavenging chickens (Gallus domesticus) and their association to body weight. Biodiversitas 21: 3163-3169. Domestic chickens (Gallus domesticus) which are traditionally fed by scavenging on farms predispose them to ectoparasites infestation. In this study, a preliminary survey was conducted on the common ectoparasites on G. domesticus in the rural areas of Banyumas. The purposes of this study were to determine the diversity of ectoparasites, their prevalence, and their relationship to the chickens body weight. This research was conducted by the survey method from December 2019 to April 2020 in five villages around the city of Purwokerto, Banyumas District, Central Java, Indonesia viz., Kedungwuluh, Kedungwringin, Kutasari, Karangsalam, and Karanggintung. Data analysis was conducted by Shannon Wiener and Evenness indexes. Analysis of variance was used to calculate the difference in prevalence among sample locations. Regression correlation analysis was used to determine the relationship between prevalence and chicken body weight. The results showed that there were six ectoparasite species  i.e., Menopon gallinae, Menacanthus cornutus, Lipeurus caponis, Dermanysus gallinae, Megninia ginglymura, and Haemaphysallis sp. parasitizing G. domesticus. The number of ectoparasite individuals among locations was significantly different (F 5.59 < 32.45; p <0.05). The most number of ectoparasite was found in Karangsalam (272 individuals). The most prevalent ectoparasite was M. cornutus (45%), followed by L. caponis (40%), and the lowest was M. synglineura (25%). Ectoparasite prevalence was associated with chicken weight loss (r = 0.98). The prevalence of ectoparasite of domestic chickens farm in the Banyumas Regency is classified as low but has the potential to influence body weight.

The Difference of Development in Children Aged 6 Months Received Exclusive Breastfeeding Versus Formula Milk in Ciptomulyo Health Center, Malang, East Java

2020 ◽  
Author(s):  
Milatur Rosyidah ◽  
◽  
Herawati Mansur ◽  
Tri Mardiyanti ◽  
◽  
...  
Keyword(s):  
Child Development ◽  
Health Center ◽  
Exclusive Breastfeeding ◽  
Cross Sectional Study ◽  
Formula Milk ◽  
Cross Sectional ◽  
Central Java ◽  
Nutritional Needs ◽  
The Difference ◽  
Keywords Child

ABSTRACT Background: Development during infancy occurs rapidly. Parent ability to meet their nutritional needs is needed to obtain optimal infants development. This study was to investigate the difference of development in children aged 6 months received exclusive breastfeeding versus formula milk Subjects and Method: A cross-sectional study was conducted at Ciptomulyo health center, Malang, East Java, from April to May 2017. A sample of 17 infants who received exclusive breastfeeding and 19 infants who received formula milk was selected by total sampling. The dependent variable was child development. The independent variables were exclusive breastfeeding and formula milk. Child development was measured by Denver Development Screening Test. Mean difference of child development between groups was measured by Mann Whitney. Results: Development score in children aged 6 months who received exclusive breastfeeding (Mean= 0.53; SD= 0.24) was higher than children who received formula milk (Mean= 0.47; SD= 0.01), and it was statistically significant (p= 0.003). Conclusion: Development score in children aged 6 months who received exclusive breastfeeding is higher than children who received formula milk. Keywords: child development, exclusive breastfeeding, formula milk Correspondence: Milatur Rosyidah. Masters Program in Public Health, Universitas Sebelas Maret. Jl. Ir. Sutami 36A, Surakarta 57126, Central Java. Email: [email protected]. Mobile: 089620575849. DOI: https://doi.org/10.26911/the7thicph.03.111

The effect of marine seismic surveys on the movement, abundance and community structure of demersal fish assemblages on the North West Shelf

2020 ◽  
Vol 60 (2) ◽  
pp. 480
Author(s):  
Mark G. Meekan ◽  
Conrad W. Speed ◽  
Robert D. McCauley ◽  
Jayson M. Semmens ◽  
Stephen J. Newman ◽  
...  
Keyword(s):  
Fish Assemblages ◽  
Demersal Fish ◽  
Seismic Survey ◽  
Survey Study ◽  
Control Zone ◽  
High Exposure ◽  
North West ◽  
Air Gun ◽  
Study Results ◽  
Demersal Fishes

In 2018, the Australian Institute of Marine Science (AIMS) and its partners, conducted an experiment to investigate the effect of exposure to a 3D seismic survey on demersal fishes. The experiment involved the use of a commercial seismic vessel equipped with a 2600 cubic inch air-gun array, sailing a racetrack pattern with eight operational (high exposure zone) and eight inactive (vessel control zone) sail lines, with a 500 m sequential line separation and ≈18 m shot point spacing. The high exposure and vessel control lines were separated by 35 km. Demersal fishes were observed in five sampling surveys over a 6-month period (three surveys before and two after exposure), using acoustic telemetry and stereo baited remote underwater videos systems (BRUVS). The telemetry component included the capture, tagging with acoustic transmitters and release of 387 red emperor (Lutjanus sebae) within two telemetry receiver arrays. These arrays, one in each zone, comprised 37 and 39 acoustic receivers over ≈32 km2, to record movements of tagged fish. The receivers provided near-continuous data on tag locations, and, hence, movement of fish in the area, until removal in December 2018. During each sampling survey, BRUVS were deployed at various distances from the area of the seismic survey. Study results are currently being finalised for presentation.

Dispersal of Silver Gulls, Larus novaehollandiae Stephens, from Breeding Colonies in South Australia

1985 ◽  
Vol 12 (2) ◽  
pp. 279 ◽  
Author(s):  
JR Ottaway ◽  
R Carrick ◽  
MD Murray
Keyword(s):  
South Australia ◽  
High Status ◽  
Dispersal Patterns ◽  
North West ◽  
Significant Difference ◽  
Rubbish Dumps ◽  
The Difference ◽  
Dispersal Distances ◽  
Almost All ◽  
The City

Dispersal of Larus novaehollandiae Stephens, from 10 colonies in South Australia, was studied during 1968-8 1 by means of bands designed for identification of free-living, uncaptured individuals. Dispersal patterns were characteristic of each colony, even for three colonies which were, at most, 10 km apart. Almost all dispersal records came from the area between Adelaide and Melbourne, and within 30 km of the coast. After breeding, the majority of gulls disperse eastwards; however, dispersal from each colony was correlated with a shift of gull population into areas where food was available from human sources such as rubbish dumps. From colonies 80 km south-east of Adelaide, a major human population, the predominant winter dispersal of these gulls was north-west, into the city and suburbs. The maximum direct-line dispersal distances recorded for 95% of the 3133 resighted gulls were <458 km. The greatest direct-line distance recorded was 1430 km. Overall, there was no significant difference in the mean dispersal distances of juveniles and adults, although at distances >480 km significantly more juveniles (<2y) were seen than adults (>2y). This involved only 2.5% of the total number of birds resighted. It is suggested that older, dominant birds maintain high status at preferred feeding places, and juveniles are possibly more erratic in their movements, as they search for food. This would account for the difference in the dispersal ofjuveniles and adults from a particular colony, and also for the significantly higher proportion of juveniles found at extreme distances from their natal colonies.

The Upwelling in the Region between Java and Australia during the South-East Monsoon

1962 ◽  
Vol 13 (3) ◽  
pp. 217 ◽  
Author(s):  
K Wyrtki
Keyword(s):  
Monsoon Season ◽  
The South ◽  
High Concentration ◽  
North West ◽  
The North ◽  
Plankton Biomass ◽  
Equatorial Current ◽  
High Concentrations ◽  
West Monsoon ◽  
Upwelling Area

An examination of the oceanographic conditions in the region between Java and Australia during the south-east monsoon season shows that the main upwelling area in this region is situated along the coast of Java and Sumbawa, and not along the north-west Australian shelf, as was previously assumed. The amount of upwelling south of Java is estimated to contribute 2.4 million m3/sec to the South Equatorial Current and the upwelling velocity is of the order of 50 × 10-5 cm/sec. The region is characterized by very high concentrations of inorganic phosphate at the bottom of the euphotic layer and by a high plankton biomass. The transparency of the water in the upwelling area is low, indicating a high concentration of suspended matter. The possible development of the upwelling during the north-west monsoon season is discussed.

scholarly journals Diel changes in acoustic and catch estimates of krill biomass

2009 ◽  
Vol 66 (6) ◽  
pp. 1318-1325 ◽  
Author(s):  
Yvan Simard ◽  
Marc Sourisseau
Keyword(s):  
Spatial Scales ◽  
Target Strength ◽  
Night Time ◽  
Diel Changes ◽  
Strobe Light ◽  
Light Pulses ◽  
Diel Vertical Migrations ◽  
Temporal And Spatial ◽  
The Difference ◽  
Fixed Distribution

Abstract Simard, Y., and Sourisseau, M. 2009. Diel changes in acoustic and catch estimates of krill biomass. – ICES Journal of Marine Science, 66: 1318–1325. Krill-biomass estimates can be compromised by diel variabilities in acoustic backscatter and the catch efficiencies of various nets. This paper describes an effort to quantify these variabilities at fine temporal and spatial scales during a three-day experiment at a fixed location, using high-resolution, stratified Bioness samples and echo-integration, and assuming a fixed distribution of krill orientations. Night-time catches in the krill scattering layer (SL) were 15 times the acoustic estimates. The situation was reversed during daytime, when the acoustic estimates in the SL were 5 times larger than the catches. This collectively resulted in a ±10‐dB gradual diel cycle in the difference of vertically integrated biomass from both sampling methods. Use of a strobe light on the Bioness reduced avoidance of the net by krill and significantly increased (×10) daytime catches in the SL, but had no significant effect on night-time catches. The difference in volume-backscattering strength at 120 and 38 kHz (ΔSv120–38) in the densest parts of the SL agreed with predictions using a target-strength (TS) model and an assumed normal distribution of tilt (mean θ = 11°; s.d. = 4°). The ΔSv120–38 was smaller for lower densities and during night-time. It appears that the θ and, therefore, TS distributions of krill significantly change during their diel vertical migrations. At twilight and at night, when they are feeding and swimming vertically, they exhibit lower mean TS and ΔSv120–38 and react less to strong strobe-light pulses, in contrast to daytime. Diel patterns in TS and net avoidance should be taken into account in krill-biomass assessments that use round the clock acoustic-survey data and multi-frequency TS models for target classification.

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