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VARIABILITY AND SPATIAL DISTRIBUTION OF TOTAL SCATTERING COEFFICIENTS OF SURFACE WATER IN VARIOUS SEASONS Untung, Murjat Hi; Nababan, Bisman; Siregar, Vincentus P.
Jurnal Ilmu dan Teknologi Kelautan Tropis Vol. 5 No. 2 (2013): Elektronik Jurnal Ilmu dan Teknologi Kelautan Tropis
Publisher : Department of Marine Science and Technology, Faculty of Fisheries and Marine Science, IPB University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1159.477 KB) | DOI: 10.29244/jitkt.v5i2.7571

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Variability and spatial distribution data of the total scattering coefficients ares useful in the development of bio-optical algorithms of ocean color satellite. The purpose of this study was to determine the variability and spatial distribution of the total scattering coefficient at 9 wavelengths (?) in different seasons. Field data collection were conducted in the Northeastern Gulf of Mexico (NEGOM) of the spring , summer, and fall in 1999-2000 by using the ac-9 in-situ Spectrophotometer and restricted to coastal waters of 10 m isobath and offshore of 1000 m isobath. The data were filtered using the moving average method and tested with the Kruskal-Wallis. The results showed that the average value of the total scattering coefficients were significantly different among spring, summer, and fall. In general, the total scattering coefficients were relatively high, especially in the coastal waters near the mouth of the river each season and relatively low in offshore waters except during the summer that the total scattering coefficients were also relatively high in offshore watersdue to the intrusion of the Mississippi river flow toward offshore containing high nutrients that can promote the growth of phytoplankton in the offshore, suspended material and lower salinity jointly to increase the total scattering coefficients.   Keywords: variability, spatial distribution, total scattering coefficient, bio-optic, NEGOM.
IDENTIFIKASI DAN INTEPRETASI AGROKLIMAT MOJOSARI, JAWA TIMUR Sugianto, Yanto; Nababan, Bisman; S., Darmijati; Syahbuddin, H.; Las, Irsal
Agromet Vol. 9 No. 2 (1993): December 1993
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1347.513 KB) | DOI: 10.29244/j.agromet.9.2.9-23

Abstract

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PEMETAAN HABITAT BENTIK BERBASIS OBJEK MENGGUNAKAN CITRA SENTINEL-2 DI PERAIRAN PULAU WANGI-WANGI KABUPATEN WAKATOBI Mastu, La Ode Khairum; Nababan, Bisman; Panjaitan, James P
Jurnal Ilmu dan Teknologi Kelautan Tropis Vol. 10 No. 2 (2018): Jurnal Ilmu dan Teknologi Kelautan Tropis
Publisher : Department of Marine Science and Technology, Faculty of Fisheries and Marine Science, IPB University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2017.861 KB) | DOI: 10.29244/jitkt.v10i2.21039

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Penelitian pemetaan habitat bentik di Pulau Wangi-wangi masih sangat sedikit dilakukan, sehingga ketersediaan data spasial habitat bentik di daerah ini sangat terbatas. Penelitian ini bertujuan untuk memetakan habitat bentik perairan dangkal menggunakan citra Sentinel-2 dengan metode klasifikasi berbasis objek/OBIA dan menghitung tingkat akurasi hasil klasifikasi habitat bentik di perairan Pulau Wangi-wangi Kabupaten Wakatobi. Penelitian ini dilaksanakan di perairan Pulau Wangi-wangi, khususnya perairan Sombu Dive dan sekitarnya. Penelitian ini menggunakan data satelit Sentinel-2 dengan resolusi spasial 10x10 m2 yang diakuisisi pada tanggal 4 April 2017 dan pengambilan data lapangan dilakukan pada bulan Maret - April 2017. Klasifikasi citra dengan metode OBIA menggunakan metode contextual editing pada level 1. Level 2 menggunakan klasifikasi terbimbing dengan beberapa algoritma klasifikasi yaitu support vector machine (SVM), decision tree (DT), Bayesian, dan k-nearest neighbour (KNN) dengan input themathic layer dari data lapangan. Klasifikasi habitat bentik dilakukan pada 12 dan 9 kelas dengan penerapan optimasi skala segmentasi yaitu 1, 1,5, 2, dan 2,5. Berdasarkan metode OBIA, habitat bentik dapat dipetakan dengan tingkat akurasi sebesar 60,4% dan 64,1% pada citra klasifikasi 12 dan 9 kelas secara berturut-turut pada nilai optimum skala segmentasi 2 dengan algoritma SVM.
CHANGE DETECTION OF CORAL REEF HABITAT USING LANDSAT IMAGERY IN MOROTAI ISLAND NORTH MALUKU PROVINCE Wahiddin, Nurhalis; Siregar, Vincentius P; Nababan, Bisman; Jaya, Indra; Wouthuyzen, Sam
Jurnal Ilmu dan Teknologi Kelautan Tropis Vol. 6 No. 2 (2014): Electronik Jurnal Ilmu dan Teknologi Kelautan Tropis
Publisher : Department of Marine Science and Technology, Faculty of Fisheries and Marine Science, IPB University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1214.66 KB) | DOI: 10.29244/jitkt.v6i2.9026

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ABSTRACT Scientific information on coral reef habitat changes of Morotai island is very limited to none. This study aimed to detect the change of coral reef habitats between 1996 and 2013, using Landsat imagery integrated with field data in 2012. The research was conducted in the coral reef ecosystem of Morotai Island in North Maluku province. Change detection analyses were conducted using supervised classifications and transformation depth invariant index (DII), with five habitat classes i.e., mixed-habitat, coral, seagrass, sand, and rubble. The result showed that in 1996-2002 there was a significant increase in the mix-habitat and rubble classes (11.3% and 32.5%), however,  there  was  a siginifcant decrease in the sand, seagrass, and coral classes of -14.1%, -14.9%, and -16.6%, respectively. In 2002-2013, mixed-habitat, sand, and seagrass classes were increase by 1.1%, 13.3%, and 24.78%, respectively.  Meanwhile, coral and rubble classes were decrease by -22.7% and -27.0%, respectively. Within the period of 1996-2013, there was about 43.6% loss of coral reef of Morotai island.  This was probably caused by the increase of seas surface temperature nad and the increase of human activities in the region. Keywords: coral reef habitats, Landsat, change detection, Morotai Island
COMPARISON OF CHLOROPHYLL CONCENTRATION ESTIMATION USING TWO DIFFERENT ALGORITHMS AND THE EFFECT OF COLORED DISSOLVED ORGANIC MATTER Nababan, Bisman
International Journal of Remote Sensing and Earth Sciences (IJReSES) Vol 5,(2008)
Publisher : National Institute of Aeronautics and Space of Indonesia (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (641.08 KB) | DOI: 10.30536/j.ijreses.2008.v5.a1232

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The effect of colored dissolved organic matter (CDOM) on the Sea-viewing Wide Field-of-view Sensor(Sea WiFS) OC4v4 and the MODIS algorithms used to estimate chlorophyll-a was studied using satellite and situ data collated during seasonal cruises in the Northeastern Gulf of Mexico between 1997 and 2000. For chlorophyll-a concentrations 50 mg m, OC4v4 generally overestimated chlorophyll-a concentration by up to 300 percent. The MODIS algorithm provided better estimates of high CDOM concentration, found typically nearshore in noterhn summer and spring. For oceanic waters where chlorophyll-a concentrations 1.0 mg m, both OC4v4 and MODIS algorithm had errors within the Sea WiFS mission specification (35 percent) during fall. The OC4v4 algorithm is more susceptible to artifacts due to CDOM absorption of light at 443 mm. Keywords: chlorophyll-a, Mississippi River Plume, Sea WiFS, upwelling, OC4v4.
VARIABILITY AND VALIDATION OF SEA SURFACE TEMPERATURE ESTIMATED BY PATHFINDER ALGORITHM OF NOAA-AVHRR SATELLITE IN THE NORTH PAPUA WATERS Nababan, Bisman; Hasyim, Bidawi; Bada, Hilda I.N.
International Journal of Remote Sensing and Earth Sciences (IJReSES) Vol 8, (2011)
Publisher : National Institute of Aeronautics and Space of Indonesia (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (558.444 KB) | DOI: 10.30536/j.ijreses.2011.v8.a1738

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Variability and validation of sea surface temperatures (SST) in north Papua waters were conducted using SST estimated by Pathfinder algorithm of NOAA AVHRR satellite and SST measurements from TAO buoy in 2001-2009. Satellite data (SST Pathfinder) were daily, weekly, and monthly composite with 4x4 km2 resolution and downloaded from http://poet.jpl.nasa.gov. In situ data (SST measurement from buoy TAO) were measured at a depth of 1.5 m and recorded every hour (http://www.pmel.noaa.gov/tao_deliv). The in situ data then converted into daily, weekly, and monthly average data. In general, the SST values of both satellite and in situ SST in the north Papua waters ranged between 27.10 - 31.90 °C. During the east season (June-September), SST values (27.90-31.90 °C) were generally higher than the SST values ( 27.10-30.13 °C) during the west season (December-February). In general, the SST values both day-time and night-time from in situ and the satellite measurements showed no significant differences except in waters close to the shore. The results also showed that the coefficient of determination values (R2) between the satellite and the in situ SST measurements were relatively low (65%) and up to 5% of RMSE. The relatively low correlation between in situ dan satellite SST measurements may be due to high cloud coverage (90-96%) in the north Papua waters so that SST satellite data become less representative of the in situ data. These results also indicated that the Pathfinder algorithm can not be used as a valid estimate of SST NOAA AVHRR satellite for the north Papua waters. Keywords: SST Pathfinder, NOAA AVHRR, Validation, TAO buoy, North Papua Waters
VARIABILITY OF CHLOROPHYLL-A CONCENTRATION AND SEA SURFACE TEMPERATURE OF NATUNA WATERS Nababan, Bisman; Simamora, Kristina
Jurnal Ilmu dan Teknologi Kelautan Tropis Vol. 4 No. 1 (2012): Elektronik Jurnal Ilmu dan Teknologi Kelautan Tropis
Publisher : Department of Marine Science and Technology, Faculty of Fisheries and Marine Science, IPB University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1188.732 KB) | DOI: 10.29244/jitkt.v4i1.7815

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Variability of chlorophyll-a concentration and sea surface temperature (SST) in Natuna waters were analyzed using satellite data Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and the National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer (NOAA-AVHRR). SeaWiFS data with a resolution of 9×9 km2 and AVHRR with a resolution of 4×4 km2 were the monthly average data downloaded from NASA website. Chlorophyll-a concentrations and SST were estimated using OC4v4 and MCSST algorithms. In general, the concentration of chlorophyll-a in Natuna waters ranged between 0.11-4.92 mg/m3 with an average of 0.56 mg/m3 during the west season and 0.09-2.93 mg/m3 with an average of 0.66 mg/m3 during the east season. Chlorophyll-a concentrations were relatively high seen in coastal areas, especially around the mouth of the Kapuas, Musi, and Batang Hari rivers allegedly caused by the high nutrient intake from the mainland. SST variability in Natuna waters ranged from 23.46-30.88 °C during the west season and tended to be lower than that the east season (27.91-31.95 °C). In addition, the SST values tended to be lower in the offshore than that inshore. During the west season (Nov-Feb) and the transitional season (Apr) in the years of Elnino Southern Oscillation (ENSO), the concentration of chlorophyll-a and the SST in Natuna waters was generally higher than that in non-ENSO years. The results of wind analyses showed that ENSO caused the change of direction and speed of wind from its normal conditions.Keywords: Sea surface temperature, chlorophyll-a, Natuna waters, ENSO, SeaWiFS, AVHRR
DOWNWELLING DIFFUSE ATTENUATION COEFFICIENTS FROM IN SITU MEASUREMENTS OF DIFFERENT WATER TYPES Nababan, Bisman; Louhenapessy, Veronica S.A.; Arhatin, Risti E
International Journal of Remote Sensing and Earth Sciences (IJReSES) Vol 10, No 2 (2013)
Publisher : National Institute of Aeronautics and Space of Indonesia (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (367.683 KB) | DOI: 10.30536/j.ijreses.2013.v10.a1851

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Process of light reduction or loss (attenuation) by scattering and absorption is affected bysolar zenith, time, depth, and seawater constituents. Downwelling diffuse attenuation coefficient (Kd)is important to understand for light penetration and biological processes in ocean ecosystem. It is,therefore, important to know the Kd value and its variability in ocean ecosystem. The objective of thisstudy was to determine downwelling diffuse attenuation coefficients and its variability form in situmeasurements of different water types. In situ downwelling irradiances (Ed) were measured using asubmersible marine environmental radiometer instrument (MER) during a clear sky, calm watercondition, and at the time range of 10:30 a.m. up to 14:00 p.m. local time in the northeastern Gulf ofMexico in April 2000. In general, Ed values decreases exponentially with depth. Ed at 380 nmexhibited the lowest attenuation (the most penetrative light), while Ed at 683 nm exhibited the highestattenuation (the most light loss at the top of water column). Overall, the Kd patterns tended to decreasefrom 380 nm to 490 nm (blue-green wavelength), and increase from 490 nm to 683 nm (green-redwavelength). Kd values in offshore region were relatively lower than in coastal region. Kd can be usedto determine the depth of euphotic zone in offshore or teh case-1 water type and the depth of oneoptical depth (the water column depth where the ocean color satellite can possibly sense).
THE GROWTH AND SURVIVAL STUDY OF PEARL OYSTER SEEDS (PINCTADA MAXIMA) BASED ON THE DIFFERENCE DEPTH LEVELS IN KAPO NTORI BAY, BUTON ISLAND Hamzah, M.S.; Nababan, Bisman
Jurnal Ilmu dan Teknologi Kelautan Tropis Vol. 1 No. 2 (2009): Elektronik Jurnal Ilmu dan Teknologi Kelautan Tropis
Publisher : Department of Marine Science and Technology, Faculty of Fisheries and Marine Science, IPB University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (190.13 KB) | DOI: 10.29244/jitkt.v1i2.7870

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Extreme change in sea surface temperature that might be influenced by global warming has negative impact on the pearl shell farming in Kapontori Bay.This change occurred above tolerance threshold for pearl shell juvenile survival at 3-4 cm shell wide that caused its mortality.The study was conducted from 28 February to 28 May 2008 at the Kapontory Bay,Buton island. The research aimed to identify growth and survival of pearl oyster seeds(Pinctada maxima) on differences of depth level.This research is important especially for pearl farming development in Southeast Sulawesi waters,as a reference basis in an effort to improve seedling survival of pearl oysters that are highly vulnerable to extremechange in temperature conditions. The variance analyses showed that the depth levels did not significantly affect the survival rates of the pearl oyster seeds (P>0,05). However, based on depth levels,higher survival rates (96.67%)were found on the depth of 2 m.Some environmental parameters in relation to the growth and survival rate of pearl oyster seed were discussed in this paper. Keywords:Depth levels,survival rate, growth, pearl shell, Kapontori Bay
MAPPING AND INDEX VEGETATION ANALYSES OF MANGROVE IN SAPARUA ISLAND, CENTRAL MOLUCCAS Waas, Harold J. D.; Nababan, Bisman
Jurnal Ilmu dan Teknologi Kelautan Tropis Vol. 2 No. 1 (2010): Elektronik Jurnal Ilmu dan Teknologi Kelautan Tropis
Publisher : Department of Marine Science and Technology, Faculty of Fisheries and Marine Science, IPB University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1748.676 KB) | DOI: 10.29244/jitkt.v2i1.7862

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2TMapping and index vegetation analyses of mangrove in coastal areas of Saparua Island, Central Moluccas was conducted using Landsat 7/ETM+ satellite data acquired in April to May 2007. The results showed that the distributions of mangrove vegetation were concentrated in the north, south, and west of the region with the area of 218.88 ha (38.26%), 105.12 ha (18.38%), and 248.04 ha (43.36%), respectively. Total area of mangrove vegetation in this island was about 572.04 ha (5.72 kmP2P), or 3.49% of the island area. Vegetation indexes (NDVI) in the north, south, and west of the region were dominated by values of >0.7 (very high density).Keyword: Mangrove, NDVI, Landsat Satellite, Saparua, Central Maluku