Seasonal Variations of Oceanographic Variables and Eastern Little Tuna (Euthynnus affinis) Catches in the North Indramayu Waters Java Sea

The MRA platform is one of the offshore platforms located in the north of the Java Sea. The MRA platform has 4 production wells, namely MRA-2ST, MRA-4ST, MRA-5, and MRA-6 wells. The 4 production wells are produced using an artificial lift in the form of a gas lift. The limited gas lift at the MRA Platform at 3.1 MMSCFD makes the production of wells at the MRA Platform not optimal because the wells in the MRA Platform are experiencing insufficient gas lift. Optimization of gas lift injection is obtained by redistribution of gas lift injection for each. The results of the analysis in this study indicate that the optimum gas lift injection for the MRA-2ST well is 0.5552 MMSCFD, the MRA-6 well is 1.0445 MMSCFD, the MRA-5 well is 0.7657 MMSCFD, finally the MRA-4ST well with gas injection. lift is 0.7346 MMSCFD. The manual gas lift in the MRA-4ST is also replaced based on an economic feasibility analysis to ensure that the gas lift injection for each well can be kept constant. The redistribution of gas lift carried out by the author has increased the total production rate of the MRA Platform by 11,160 BO/year or approximately USD 781,200/year. Keywords: Gas lift; Insufficient; Optimization

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HUBUNGAN IKAN PELAGIS DENGAN KONSENTRASI KLOROFIL-A DI LAUT JAWA

BAWAL Widya Riset Perikanan Tangkap ◽

10.15578/bawal.6.1.2014.21-29 ◽

2015 ◽

Vol 6 (1) ◽

pp. 21

Author(s):

Kamaluddin Kasim ◽

Setiya Triharyuni ◽

Arief Wujdi

Keyword(s):

Chlorophyll A ◽

Aquatic Organism ◽

Predator Species ◽

Pelagic Species ◽

Photosynthetic Organisms ◽

Bivariate Correlation ◽

Java Sea ◽

Rastrelliger Kanagurta ◽

Euthynnus Affinis ◽

As Relationship

Klorofil-a banyak ditemukan pada fitoplankton dan menjadi indikator kesuburan perairan. Keberadaan fitoplankton ditandai dengan kandungan klorofil-a yang tinggi dan diikuti oleh keberadaan zooplankton yang akhirnya mempengaruhi keberadaan organisme perairan lainnya seperti ikan pelagis kecil maupun ikan pelagis besar sebagai suatu rantai makanan. Interaksi antara konsentrasi klorofil-a terhadap keberadaan dan konsentrasi ikan pelagis di Laut Jawa belum banyak diketahui. Penelitian ini dimaksudkan untuk mengetahui hubungan interaksi antara klorofil-a terhadap konsentrasi ikan pelagis. Penelitian dilakukan dengan mengumpulkan data runtun waktu hasil tangkapan beberapa jenis pelagis besar dan kecil yang didaratkan di PPI Pekalongan tahun 2007-2011 serta data runtun waktu konsentrasi klorofil-a dari perairan utara Jawa yang diperoleh dari informasi sekunder.Metode analisis korelasi linear sederhana (bivariate correlation) digunakan untukmengetahui ada atau tidaknya pengaruh antar variabel klorofil-a dan konsentrasi ikan pelagis. Hasil penelitian menunjukkan bahwa ikan layang (Decapterus russelli) paling nyata mendapat pengaruh dari konsentrasi klorofil-a (P<0,05) dan berkorelasi positif terhadap konsentrasi klorofil-a dengan nilai koefisien korelasi ( r ) sebesar 0,56, sedangkan ikan pelagis lainnya berkorelasi negatif. Ikan tongkol (Euthynnus affinis) posisinya menempati rantai makanan paling tinggi sebagai pemangsa, mempunyai korelasi positif (r = 0,5) terhadap Rastrelliger kanagurta dan r = 0,56 terhadap Amblygaster sirm.Chlorophyll-a is a light-absorbing pigment that can be found in photosynthetic organisms such as algae and phytoplankton. The evidence of phytoplankton that indicated by high contents of chlorophyll-a may followed the evidence of zooplankton and other micro aquatic organism as a food chain component. An overview of interrelationships between chlorophyll-a and pelagic fishes in the waters around Java Sea have not much investigated. The research was attempted to study the interaction between chlorophyll-a abundance and the abundance of small and large pelagic as well as relationship among small and large pelagic as prey-predators component. Research conducted by collecting time series catch data of small and large pelagic species landed at PPI Pekalongan during the period of 2006-2012, as well as the data of chlorophyll-a abundance through previous research studies. The results showed that layang (Decapterus russelli) was the most significant species that positively correlated to abundance of chlorophyll-a (P < 0.05) with value of r = 0.6. while others pelagic species have negative correlation. As a predator species, tongkol (Euthynnus affinis) was positively correlated ( r = 0.5) to the abundance of banyar (Rastrelliger kanagurta) as well as juwi (Amblygaster sirm) with r value 0.56.

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THE CONFIGURATION OF MASS LAY-OUT AND EXTERNAL SPACE EXPLOITATION OF FISHING VILLAGES Study objects: The Fishing Villages of Cilincing and Marunda in North Jakarta

Riset Arsitektur (RISA) ◽

10.26593/risa.v1i1.2279.17-36 ◽

2017 ◽

Vol 1 (1) ◽

pp. 17-36

Author(s):

Levina Levina

Keyword(s):

Fishing Community ◽

Exterior Space ◽

Fishing Villages ◽

The North ◽

Physical Data ◽

Architectural Features ◽

Java Sea ◽

Data Collection Technique ◽

The One

Abstract- Cilincing and Marunda are two kampongs situated in the north of Jakarta, immediately bordering on the Java Sea. The existence of the fishing villages sketches the lives of these communities. They make their living out of catching fish and other produce, so the lives of the fishing community take place between water and land. This situation has led to their settlement differing from others in the urban kampong. The synergy stimulated by the water-based context has inspired the unique architectural features of these villages, in terms of planning the lay-out of the dwelling-places or residential area.This research study is a descriptive-comparative analysis of the exploitation of exterior space based on the configuration pattern of the mass lay-out of the fishing villages observed. The data collection technique consists of gathering the relevant physical data along with those covering related activities. The physical data have been obtained by way of field mapping and observation, while the data concerning activities have been collected through observation and interviews conducted with the respondents, namely the inhabitants of the Cilincing fishing village (RT 012) and of Marunda (RT 03). The data have been divided based on the major outdoor activities of the community involved (sea-faring and residing). Finally, a comparison has been drawn between the research results of these two villages.The findings indicate that the configuration of the mass lay-out in these two fishing villages has created a quality of exterior space exploitation that is different as well. The one that displays a scattered lay-out pattern has a large volume of exterior space at its disposal that is left unexploited by its inhabitants, both for sea-bound activities and residential land-bound ones. The propinquity of the mass has created exterior space that is more intimate in nature.Keywords: Configuration of mass lay-out, exterior space

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Seasonal Variations of the Synoptic-Scale Transient Eddy Activity and Polar Front Jet over East Asia

Journal of Climate ◽

10.1175/2009jcli3225.1 ◽

2010 ◽

Vol 23 (12) ◽

pp. 3222-3233 ◽

Cited By ~ 56

Author(s):

Xuejuan Ren ◽

Xiuqun Yang ◽

Cuijiao Chu

Keyword(s):

East Asia ◽

Seasonal Variations ◽

East Asian ◽

Polar Front ◽

Transient Eddy ◽

Synoptic Scale ◽

Wind Fields ◽

The North ◽

Upper Level ◽

Polar Front Jet

Abstract Seasonal variations of the synoptic-scale transient eddy activity (STEA) and the jet streams over East Asia are examined through analysis of the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) data. Extracted from the 6-hourly upper-level wind fields, the distribution of the jet core numbers exhibits a distinct geographical border for the East Asian subtropical jet (EASJ) and the East Asian polar front jet (EAPJ) at the latitudes of the northern Tibetan Plateau (TP). In the cool seasons, two branches of the STEA and low-level baroclinicity exist over the East Asian landmass, accompanied by the two-jet state of the EASJ and EAPJ. In the warm seasons, a single jet pattern of the EASJ along the north flank of the TP is accompanied by the weakened STEA over the mid- to high latitudes of East Asia. Further analysis shows two distinct features of the seasonal variations of the STEA over East Asia, compared with that over the North Pacific. First, during the transitional period of April–June, the main STEA band over East Asia migrates northward dramatically, in conjunction with the EAPJ shifting in the same direction. Second, both the upper-level STEA and the lower-level baroclinicity poleward of the TP are prosperous in spring. The relationship between the STEA, baroclinicity, vertical wind shear, and static stability in the EAPJ region in different seasons is further investigated. It is found that in addition to the time-mean wind fields, the rapid increase in the sensible heat flux poleward side of the TP region in spring and the associated boundary layer processes are partially responsible for the spring prosperity of the local baroclinicity and the STEA.

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Seasonal variations in the water quality, diversity and population ecology of intertidal macrofauna at an industrially influenced coast

Water Science & Technology ◽

10.2166/wst.2010.503 ◽

2010 ◽

Vol 61 (6) ◽

pp. 1505-1514 ◽

Cited By ~ 7

Author(s):

A. Vaghela ◽

P. Bhadja ◽

J. Ramoliya ◽

N. Patel ◽

R. Kundu

Keyword(s):

Water Quality ◽

Seasonal Variations ◽

Anthropogenic Activities ◽

Habitat Destruction ◽

Anthropogenic Pressure ◽

The North ◽

Physico Chemical ◽

Littoral Zones ◽

Reported Data ◽

Physical And Chemical

Present communication reports the physico-chemical and biological quality of seawater and status of benthos of a highly industrialized shore of the north-western coastline of India. The coastal area considered for the present study, encircled by a variety of industries, was divided into two sampling sites and monitored for two consecutive years. Results of the water quality suggest that the obtained values of the physical and chemical parameters of seawater were comparable with data reported earlier. However, data obtained in the biological parameters of the seawater showed a declining trend. Results of the intertidal macrofaunal diversity studies revealed that the muddy upper littoral zones were represented by few species of coelenterata, porifera, arthropoda and mollusca. In the rocky—muddy middle littoral zones, gastropods, stars fishes, corallites, crabs, polychetes and tubeworms were present, whereas, predominantly rocky lower littoral zones were comparatively rich in macrofaunal diversity with small patches of coral colonies. However, when the results obtained in the present study was compared with that of earlier reported data, it was clear that the macrofaunal diversity indeed declined considerably over the years. This may be due to habitat destruction and habitat alteration in the coastline caused by increased anthropogenic activities in the area. Seasonal variations in the population density and abundance were observed in most of the faunal groups except in sessile corals and sponges. This may be due to local migration of the faunal groups towards deeper regions of the Gulf, as supported by the analysis of similarity, to avoid influx of freshwater during monsoon, and high temperature during summer and post monsoon seasons. The overall assessment of different parameters of this study revealed that though the physico- chemical characteristics of the seawater did not varied much from the earlier reported status, the biological characteristics of the seawater and intertidal zone was affected possibly by a high degree of anthropogenic pressure.

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Physical properties of the Great Barrier reef Lagoon waters near Townsville. II. Seasonal variations

Marine and Freshwater Research ◽

10.1071/mf9810321 ◽

1981 ◽

Vol 32 (3) ◽

pp. 321 ◽

Cited By ~ 21

Author(s):

E Wolanski ◽

M Jones ◽

WT Williams

Keyword(s):

Physical Properties ◽

Great Barrier Reef ◽

Seasonal Variations ◽

High Salinity ◽

Dry Season ◽

Barrier Reef ◽

Reef Lagoon ◽

The North ◽

Strong Winds ◽

Calm Weather

The distribution of salinity, temperature, suspended particles, light transmissivity, chlorophyll a and phaeopigments across the Great Barrier Reef lagoon offshore Townsville, was measured from 9 January 1979 to 23 January 1980 at approximately weekly intervals. Previous observations at Low Isles. 400 km to the north, on seasonal variations of temperature and salinity were generally applicable here. A shallow summer thermocline was frequently observed in offshore waters, in the dry season and in calm weather. As a result of evaporation from the lagoon and adjoining mangrove swamps during the dry season, an inverse estuarine circulation can exist when high salinity, sediment-rich, nearshore waters sink below the less saline offshore waters. Only nearshore were bottom sediments strongly entrained in the water column during strong winds, principally in winter.

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Seasonal variations in physiological parameters of phytoplankton across the North Atlantic

Journal of Plankton Research ◽

10.1093/plankt/20.1.17 ◽

1998 ◽

Vol 20 (1) ◽

pp. 17-42 ◽

Cited By ~ 34

Author(s):

Margareth N. Kyewalyanga ◽

Trevor Platt ◽

Shubha Sathyendranath ◽

Vivian A. Lutz ◽

Venetia Stuart

Keyword(s):

North Atlantic ◽

Seasonal Variations ◽

Physiological Parameters ◽

The North ◽

The North Atlantic

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Seasonal variations in the occurrence of Vibriovulnificusalong the Dutch coast

Epidemiology and Infection ◽

10.1017/s0950268800057691 ◽

1994 ◽

Vol 112 (2) ◽

pp. 285-290 ◽

Cited By ~ 23

Author(s):

J. Veenstra ◽

P. J. G. M. Rietra ◽

J. M. Coster ◽

E. Slaats ◽

S. Dirks-Go

Keyword(s):

Seasonal Variation ◽

Water Temperature ◽

North Sea ◽

Seasonal Variations ◽

Water Samples ◽

Human Disease ◽

Sea Water ◽

Dutch Coast ◽

The North ◽

The North Sea

SUMMARYThe seasonal variation in the occurrence ofV. vulnificusin relation to water temperature and salinity was studied along the Dutch coast. In two consecutive yearsV. vulnificusstrains could be isolated in August when the water temperature was highest. The indole-positive strains isolated from North Sea water samples were identical to most strains isolated from human disease and from the environment. However, strains isolated from four of five patients living in countries around the North Sea were different from the North Sea isolates in that they were indole-negative and have a lower NaCl tolerance.

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Spatial and seasonal variations of aerosols over China from two decades of multi-satellite observations. Part I: ATSR (1995–2011) and MODIS C6.1 (2000–2017)

10.5194/acp-2018-287 ◽

2018 ◽

Cited By ~ 1

Author(s):

Larisa Sogacheva ◽

Gerrit de Leeuw ◽

Edith Rodriguez ◽

Pekka Kolmonen ◽

Aristeidis K. Georgoulias ◽

...

Keyword(s):

Seasonal Variations ◽

Eastern Coast ◽

Data Sets ◽

Imaging Spectrometer ◽

The North ◽

Deep Blue ◽

Modis Aod ◽

Yearly Average ◽

Moderate Resolution ◽

Terra Satellite

Abstract. Aerosol optical depth (AOD) patterns and interannual and seasonal variations over China are discussed based on the AOD retrieved from the Along-Track Scanning Radiometer (ATSR-2, 1995–2002), the Advanced ATSR (AATSR, 2002–2012) (together ATSR) and the Moderate Resolution Imaging spectrometer (MODIS) aboard the Terra satellite (2000–2017). The AOD products used were the ATSR Dual View (ADV) v2.31 AOD and MODIS/Terra Collection 6.1 (C6.1) merged dark target (DT) and deep blue (DB) AOD product. Together these data sets provide an AOD time series for 23 years, from 1995 to 2017. Differences between the MODIS C6.1 and C6 AOD products with respect to AOD coverage and validation with Aerosol Robotic Network (AERONET) over China are briefly discussed, showing better validation results for C6.1: the correlation coefficient has increased from 0.9 in C6 to 0.92 in C6.1; bias has been slightly lowered from 0.007 to 0.006. ADV and MODIS AOD validation results show similar high correlation with AERONET AOD (0.88 and 0.92, respectively), while the corresponding bias is positive for MODIS (0.06) and negative for ADV (−0.07). Validation of the AOD products in similar conditions, when ATSR and MODIS/Terra overpasses are within 90 minutes from each other and when both ADV and MODIS retrieve AOD, show that ADV performs better than MODIS in autumn, while MODIS performs slightly better in spring and summer. In winter, both ADV and MODIS underestimate AERONET AOD. Similar AOD patterns are observed by ADV and MODIS in annual and seasonal aggregates. ADV-MODIS difference maps show that MODIS AOD is generally higher than that from ADV. During the period 1995–2006, AOD was increasing in the SE of China. Between 2006 and 2011, AOD was not changing much, showing minor minima in 2008–2009. From 2011 onward, AOD is decreasing in the SE of China. Both ADV and MODIS show similar seasonal AOD behavior. The spring AOD maxima in the south is shifting from spring to summer along the eastern coast in the direction to the north. Similar patterns exist in year-to-year ADV and MODIS annual AOD tendencies in the overlapping period. The agreement between sensors in year-to-year AOD changes is quite good. The large AOD differences exist between regions, for both sensors. The consistency between ATSR and MODIS as regards the AOD tendencies in the overlapping period is rather strong in summer, autumn and overall for the yearly average, while in winter and spring, when there is a difference in coverage between the two instruments, the agreement in the AOD tendencies is lower.

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