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STUDI KERAPATAN DAN PERUBAHAN TUTUPAN MANGROVE MENGGUNAKAN CITRA SATELIT DI PULAU SEBATIK KALIMANTAN UTARA Hendrawan, .; Gaol, Jonson Lumban; Susilo, Setyo Budi
Jurnal Ilmu dan Teknologi Kelautan Tropis Vol. 10 No. 1 (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 | DOI: 10.29244/jitkt.v10i1.18595

Abstract

Hutan mangrove merupakan ekosistem yang rentan sehingga membutuhkan pemantauan terus menerus untuk mendeteksi berbagai ancaman seperti aktivitas manusia dan bencana alam. Pengindraan jauh dan sistem informasi geografis (SIG) merupakan alat yang sangat efektif untuk digunakan dalam pemantauan ekosistem mangrove karena dapat menjangkau daerah yang luas dan dapat dilakukan sekala berkala. Penerapan teknologi pengindraan jauh untuk memantau ekosistem mangrove di Pulau Sebatik belum pernah dilakukan sebelumnya. Penelitian ini penting untuk mengetahui perubahan kondisi hutan mangrove di Pulau Sebatik. Tujuan dari penelitian ini adalah menganalisis korelasi antara nilai Normalized Different Vegetation Index (NDVI) dan persentase tutupan kanopi mangrove, menghitung akurasi klasifikasi tutupan lahan dengan resolusi spasial yang berbeda, dan mengukur perubahan sebaran mangrove dari tahun 2005 sampai 2016. Klasifikasi tutupan lahan dalam penelitian ini menggunakan klasifikasi terbimbing dengan algoritma Maximum Likelihood. NDVI digunakan sebagai indikator kerapatan tutupan mangrove. Pengukuran data lapangan diambil untuk menghitung tutupan kanopi. Penilaian akurasi klasifikasi citra Landsat sekitar 83% dan citra SPOT 6 sekitar 90%. Mangrove di Pulau Sebatik mengalami peningkatan dari tahun 2005 sampai 2016 sebesar 31,27%. Korelasi antara NDVI dan tutupan kanopi dikategorikan tinggi dengan koefisien korelasi r = 0,82 (Landsat 8) dan 0,85 (SPOT 6).
VARIABILITY OF CHLOROPHYLL-A CONCENTRATION OF THE NORTHERN SUMBAWA WATERS BASED ON SEA WIFS SATELLITE DATA Nababan, Bisman; Zulkarnaen, Diki; Gaol, Jonson Lumban
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 (6968.801 KB) | DOI: 10.29244/jitkt.v1i2.7875

Abstract

Variability of chlorophyll-a concentrations of the northern Sumbawa waters was investigated based on SeaWiFS satellite data for the period of January 1998-December 2007. Chlorophyll-aconcentration was estimated employing OC4v4 algorithm. Chlorophyll-a concentrations of,SeaWiFS satellite data were obtained from the Goddard Space Flight Center, NASA archieve data. In general, fluctuations of chlorophyll-a concentration of the northern Sumbawa waters had three patterns i.e., the maximum with a range of 0,21-0,74 mg/m3 occurred during the West Season (November-February), the minimum with a range of 0.12-0.15 mg/m3 occurred during Transition Season I (March-April), and relatively high (second peak) with a range of 0.21-0.36 mg/m3 occurred during the mid-East Season until the beginning of Transition Season II (July-September).High chlorophyll-a concentration occurred during the West Season was closely related to the high rainfall, the possibility of vertical water mass mixing,and upwelling process in the northern coastal waters of Sumbawa. Meanwhile, the relatively high (second peak) of chlorophyll-aconcentration occurred in July-September was caused by the movement of water masses from the South of Makassar Strait containing relatively high chlorophyll-a concentrations and relatively low temperatures since upwelling processes occurred at this location in the same period. Keywords:Chlorophyll-a,northern Sumbawa waters, SeaWiFS, OC4v4, upwelling  
ALGORITMA UNTUK DETEKSI TUMPAHAN MINYAK DI LAUT TIMOR MENGGUNAKAN CITRA MODIS Sudibjo, Muhammad; Siregar, Vincentius P.; Gaol, Jonson Lumban
Jurnal Teknologi Perikanan dan Kelautan Vol 4 No 1 (2013): MEI 2013
Publisher : Fakultas Perikanan dan Ilmu Kelautan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1148.41 KB) | DOI: 10.24319/jtpk.4.41-62

Abstract

Tumpahan minyak di Laut Timor yang terjadi pada tahun 2009 telah menyebarkan minyak seluas 10.842.81 km2. Tumpahan minyak ini berhasil dideteksi oleh satelit Moderate Resolution Imaging Spectroradiometer (MODIS). Tujuan dari penelitian ini adalah membandingkan hasil deteksi tumpahan minyak dari beberapa algoritma dengan citra menggunakan citra MODIS dan melihat perbedaan visual yang dihasilkan. Algoritma yang digunakan adalah Oil Spill Index, Fluorescence Index, Principal Component Analysis (PCA), Normalized Difference Vegetation Index (NDVI). Visualisasi tumpahan minyak yang terlihat pada citra MODIS dengan algoritma oil spill indeks dan fluorescence index lebih cerah dibandingkan dengan badan air disekitarnya dan juga memiliki nilai piksel lebih tinggi, sedangkan visualisasi minyak menggunakan algoritma PCA dan NDVI lebih gelap dibandingkan dengan badan air disekitarnya dan juga memiliki nilai piksel yang lebih rendah. Hasil uji akurasi yang dilakukan terhadap algoritma oil splill index, fluorescence index, PCA, NDVI berturut-turut sebagai berikut 41%, 46%, 41%, dan 60%
HUBUNGAN KONSENTRASI KLOROFIL-A DAN SUHU PERMUKAAN LAUT DENGAN HASIL TANGKAPAN IKAN PELAGIS UTAMA DI PERAIRAN LAUT JAWA DARI CITRA SATELIT MODIS Putra, Ega; Gaol, Jonson Lumban; Siregar, Vincentius P.
Jurnal Teknologi Perikanan dan Kelautan Vol 3 No 2 (2012): NOVEMBER 2012
Publisher : Fakultas Perikanan dan Ilmu Kelautan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1173.748 KB) | DOI: 10.24319/jtpk.3.1-10

Abstract

This research aims to study spatial and temporal variation of chlorophyll-a concentration and sea surface temperature as well as his relationship with pelagic fish catches in Java Sea. The results showed in 2006th-2010th sea surface temperaturerice occurs by 1°C which monthly average range between 27,9°C ? 31,4°C. Sea surface temperature are relatively higher in transitional seasons compared to west season and east season. Chlorophyll-a concentration in area of research ranging from 0,22 mg/m³- 1,15 mg/m³. Chlorophyll-a concentration value each month fluctuates follow wind of progress. Maximum value of chlorophyll-a concentration happening in wesh season and minimum value occurs in transitional season 2. Layang scad, banyar fish and eastern little tuna has a negative response to sea surface temperature especially in east season. As for sardine fish and fringescalle sardine show absence of a direct relationshop between sea surface temperature with CPUE value catches. Sardine fish and fringescalle sardine show any positive response to rising chlorophyll-a concentration, while for layang scad, banyar fish and eastern little tuna an increase value of chlorophyll-a concentration does not have a direct impact on rising CPUE value of third type of this fish.
ESTIMATION OF COASTAL UPWELLING INDEX USING AQUA-MODIS SATELLITE CENSOR IN SOUTH JAVA AND WEST SUMATERA Silubun, Dortje Theodora; Gaol, Jonson Lumban; Naulita, Yuli
Jurnal Teknologi Perikanan dan Kelautan Vol 6 No 1 (2015): MEI 2015
Publisher : Fakultas Perikanan dan Ilmu Kelautan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3793.54 KB) | DOI: 10.24319/jtpk.6.21-29

Abstract

Monsoonal upwelling generally occurred along the coasts of South Java to Western Sumatera. The aimed of this study was to estimate the upwelling intensity derived from sea surface temperature (SST) and chlorophyll-a. SST and chlorophyll-a data was obtained from 3rd level of Aqua-MODIS satellite censor, and wind data derived from Quikscat satellite censor on July 2002 to June 2011. Upwelling index derived from coastal upwelling index (CUIx) formula. Statistical analysis was used to describe the relationship of SST and chlorophyll-a to CUIx. The result of this study show that the occurrence of upwelling was in east monsoon temporally, the range of SST is about 25.10 ? 27.30 °C and chlorophyll-a is about 0.30 ? 0.67 mg m-3. However in 2006 the anomaly of upwelling intensity coincide perfectly with the descend of SST to 24.98 °C (Sout Java) and 25.97 °C (West Sumatera), meanwhile the concentration of chlorophyll-a is increase to 1.3 mg m-3 (West Sumatra) and 3.71 mg m-3 (South Java). Statistical analysis show that the SST give a strong relationship between CUIx and SST (r=0.84) in West Sumatera. Meanwhile in South Java, both of those parameters (SST and Chlorophyll-a) gives the strong relationship to CUIx respectively (r= 0.86 and r = 0.81).
DETECTION OF POTENTIAL FISHING ZONES OF BIGEYE TUNA (THUNNUS OBESUS) AT PROFUNDITY OF 155 M IN THE EASTERN INDIAN OCEAN Fachruddin-Syah, Achmad; Gaol, Jonson Lumban; Zainuddin, Mukti; Apriliya, Nadela Rista; Berlianty, Dessy; Mahabror, Dendy
Indonesian Journal of Geography Vol 52, No 1 (2020): Indonesian Journal of Geography
Publisher : Faculty of Geography, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijg.43708

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Remotely sensed data and habitat model approach were employed to evaluate the present of oceanographic aspect in the Bigeye tuna's potential fishing zone (PFZ) at a profundity of 155 m. Vessel monitoring system was employed to acquire the angling vessels for Bigeye tuna from January through December, 2015-2016. Daily data of sub-surface temperature (Sub_ST), sub-surface chlorophyll-a (Sub_SC), and sub-surface salinity (Sub_SS) were downloaded from INDESO Project website. Vessel monitoring system and environmental data were employed for maximum entropy (maxent) model development. The model predictive achievement was then estimated applying the area under the curve (AUC) value. Maxent model results (AUC>0.745) exhibited its probable to understand the Bigeye tuna's spatial dispersion on the specific sub-surface. In addition, the results also showed Sub_ST (43,1%) was the most affective aspect in the Bigeye tuna dispersion, pursued by Sub_SC (35,2%) and Sub_SS (21,6%).
VARIASI DATA SUHU PERMUKAAN LAUT, TINGGI PARAS LAUT, KLOROFIL-A, DAN UPWELLING DI PERAIRAN SELATAN JAWA SERTA KORELASINYA DENGAN DATA LAPANGAN Rachman, Herlambang Aulia; Gaol, Jonson Lumban; Syamsudin, Fadli
Journal of Marine and Aquatic Sciences Vol 5 No 2 (2019)
Publisher : Fakultas Kelautan dan Perikanan Universitas Udayana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24843/jmas.2019.v05.i02.p17

Abstract

 Perairan Selatan Jawa merupakan wilayah yang memiliki dinamika yang cukup kompleks karena dipengaruhi oleh beberapa faktor baik secara regional atau global. Adanya pengaruh tersebut tentu berdampak terhadap variasi kondisi oseanografi di perairan seperti Suhu Permukaan Laut (SPL), Tinggi Paras Laut (TPL), dan Klorofil-a. Observasi data oseanografi pada saat ini telah banyak dilakukan, salah satunya dengan metode pengindraan jauh. Tujuan dalam penelitian ini adalah menghitung variasi bulanan dari kondisi oseanografi berdasarkan data satelit dan korelasinya dengan data lapangan. Hasil validasi menunjukkan data SPL dan ATPL dengan data lapangan memiliki hubungan cukup baik, dimana nilai R2 mencapai 0.74 dan 0.9. Variasi data oseanografi secara umum memiliki pola yang sama yakni berubah secara musiman. Data SPL dan ATPL berada pada kondisi maksimum pada periode bulan Januari-Maret, sedangkan minimum pada Juli-September. Sedangkan konsentrasi klorofil-a berada kondisi maksimum pada Juli-September dan minimum pada Januari-Maret. Hal tersebut diduga adanya fenomena upwelling yang terjadi pada Juli-September akibat adanya pergerakan angin muson. Hasil perhitungan indeks upwelling berdasarkan data angin menunjukkan bahwa pada periode Juni hingga September merupakan puncak terjadinya upwelling.
CHLOROPHYLL-A CONCENTRATIONS ESTIMATION FROM AQUA-MODIS AND VIIRS-NPP SATELLITE SENSORS IN SOUTH JAVA SEA WATERS Nuris, Rayhan; Gaol, Jonson Lumban; Prayogo, Teguh
International Journal of Remote Sensing and Earth Sciences (IJReSES) Vol 12, No 1 (2015)
Publisher : National Institute of Aeronautics and Space of Indonesia (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.ijreses.2015.v12.a2673

Abstract

This study aimed to estimate the concentration of chlorophyll-a from satellite imagery of National Polar-Orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP) in the south Java Sea waters and compare it to the concentrations of chlorophyll-a estimation result from the MODIS-Aqua satellite. NPP satellite had Visible/Infrared Imager Radiometer Suite (VIIRS) sensors which performance was same as Moderate Resolution Imaging Spectroradiometer (MODIS) sensor with a better spatial resolution. This study used daily satellite imagery of VIIRS-NPP for the period of September 2012 to August 2013. The algorithm that was used to estimate the concentration of chlorophyll-a was Ocean Color 3-band ratio (OC-3). The results showed that the spatial distribution pattern of chlorophyll-a concentration between VIIRS - NPP sensor and MODIS had the same pattern, but the estimation of chlorophyll-a concentration from the MODIS sensor was higher than VIIRS -NPP sensor. The concentration of chlorophyll-a showed that there were spatial and temporal variation in the south Java Sea waters. Generally, concentrations of chlorophyll-a was higher in East monsoon than West monsoon.
COASTAL UPWELLING UNDER THE INFLUENCE OF WESTERLY WIND BURST IN THE NORTH OF PAPUA CONTINENT, WESTERN PACIFIC Waas, Harold J.D.; Siregar, Vincentius P; Jaya, Indra; Gaol, Jonson Lumban
International Journal of Remote Sensing and Earth Sciences (IJReSES) Vol 9, No 2 (2012)
Publisher : National Institute of Aeronautics and Space of Indonesia (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.ijreses.2012.v9.a1837

Abstract

Coastal upwelling play an important role in biological productivity and the carbon cycle in the ocean. This research aimed to examine the phenomenon of coastal upwelling that occur in the coastal waters north of Papua continent under the influence of Westerly Wind Burst(WWB) prior to the development of El Nino in the Pacific. Data consisted of sea surface temperature, vertical oceanic temperature, ocean color satellite image, wind stress and vector wind speed image, sea surface high, and Nino 3.4 index. Coastal upwelling events in the northern coastal waters of Papua continent occurred in response to westerly winds and westerly wind burst (WWBs) during December to March characterizing by low sea surface temperature (SST) (25 - 28C), negative sea surface high deviation and phytoplankton blooming, except during pre-development of the El Nino 2006/2007 where weak upwelling followed by positive sea surface high deviation. Strong coastal upwelling occurred during two WWBs in December and March1996/1997 with maximum wind speed in March produced a strong El Nino 1997/1998. Upwelling generally occurred along coastal waters of Jayapura to Papua New Guinea with more intensive in coastal waters north of Papua New Guinea indicated by Ekman transport and Ekman layer depth maximum.
GROWTH RATE AND PRODUCTIVITY DYNAMICS OF ENHALUS ACOROIDES LEAVES AT THE SEAGRASS ECOSYSTEM IN PARI ISLANDS BASED ON IN SITU AND ALOS SATELLITE DATA Rustam, Agustin; Bengen, Dietriech Geoffrey; Arifin, Zainal; Gaol, Jonson Lumban; Arhatin, Risti Endriani
International Journal of Remote Sensing and Earth Sciences (IJReSES) Vol 10, No 1 (2013)
Publisher : National Institute of Aeronautics and Space of Indonesia (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.ijreses.2013.v10.a1847

Abstract

Enhalus acoroides is the largest population of seagrasses in Indonesia. However, growth rate  and  productivity  analyses  of Enhalus  acoroides and  the use  of  satellite data to estimate its the productivity are still rare. The goal of the research was to analyze the growth rate, productivity rate,seasonal productivity of Enhalus acoroides in Pari island and its surroundings. The study was divided into two phases i.e., in situ measurments and satellite image processing. The field study was conducted to obtain the coverage percentage, density, growth rate, and productivity rate, while the satellite image processing was used to estimate the extent of seagrass. The study was conducted in August 2011 toJuly  2012  to  accommodate  all  four  seasons. Results  showed  that  the highest  growth  rate  andproductivity occurred during the transitional season from west Monsoon to the east Monsoon of 5.6cm/day  and  15.75  mgC/day, respectively.   While, the  lowest growth rate  and productivity occurred during  the  transition  from east  Monsoon  to  the  west  Monsoon of 3.93  cm/day  and  11.4  mgC/day, respectively. Enhalus  acoroides productivity reached its maximum during  the  west  Monsoon  at 1081.71 mgC/day/m2 and minimum during east Monsoon with 774.85 mgC/day/m2 . Based on ALOS data in 2008 and 2009, total production of Enhalus acoroides in the proximity of Pari islands reached its maximum occur during the west Monsoon (48.73 – 49.59 Ton C) and minimum during transitional season (16.4-16.69 Ton C). Potential atmospheric CO2 absorption by Enhalus acoroides in Pari island was estimated at the number 60.14 – 181.82 Ton C.