Alfi Satriadi
Departemen Oseanografi, Fakultas Perikanan Ilmu Kelautan, Universitas Diponegoro Jl. Prof. H. Sudarto, SH, Tembalang, Kota Semarang, Kode Pos 50275 Telp/fax (024) 7474698

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Journal : Journal of Marine Research

KAJIAN KERENTANAN BENCANA TSUNAMI DI PESISIR KABUPATEN KULON PROGO PROVINSI D. I. YOGYAKARTA Widyawati, Ari; Handoyo, Gentur; Satriadi, Alfi
977-2407769
Publisher : Departemen Ilmu Kelautan, Fakultas PerikanJurusan Ilmu Kelautan, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (200.015 KB) | DOI: 10.14710/jmr.v2i2.2772

Abstract

Coastal of Kulon Progo Regency is located in the southern coastal area of Java island that potentially vulnerable to tsunami disaster because of its geographical position that directly opposite the Indian Ocean and the meeting place of two tectonic plates, the Eurasian plate and the Indo- Australian plate which is tectonically very active and can be tsunami source. Identification of tsunami vulnerable areas in Kulon Progo Regency is a disaster mitigation step to minimize the negative impact of the tsunami. The purpose of this research is to map the vulnerability of the environment to the tsunami in Kulon Progo Regency coastal. There are five classes of tsunami vulnerabilities in Kulon Progo Regency coastal is the particularly vulnerable class 7.77 km2, 19.82 km2 vulnerable class, the class is quite vulnerable 33.98 km2, 51.38 km2 less vulnerable class, and the class is not vulnerable 31.19 km2 . The area included in very susceptible and vulnereable class in the village of Glagah, Jangkaran, Karang Sewu, Banaran, Sindutan, Palihan, Garongan, Pleret, and Bugel. The class are quit vulnerable, less vulnerable, and not vulnerable include around the village areas of reserarch in Galur, Panjatan, Wates, and Temon district.
Studi Hubungan Kerapatan Vegetasi Lamun dengan Laju Sedimentasi di Perairan Teluk Awur dan Bandengan Jepara Pada Periode Juni – Juli 2012 Nursanti, Nursanti; Riniatsih, Ita; Satriadi, Alfi
977-2407769
Publisher : Departemen Ilmu Kelautan, Fakultas PerikanJurusan Ilmu Kelautan, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1519.429 KB) | DOI: 10.14710/jmr.v2i3.3128

Abstract

Teluk Awur and Bandengan waters are located in Jepara which have different conditions and also the waters are still good for seagrass growth. Seagrass has one physical function as a sediment catcher in coastal waters. The sedimentation rate in the Teluk Awur and Bandengan waters affected by seagrass density, flow velocity, and sediment composition. The purpose of this research is to determine the relationship of seagrass vegetation density with the rate of sedimentation in the Teluk Awur and Bandengan waters, Jepara. This reaserch was conducted in June-July 2012. in the Teluk Awur waters discovered 6 genus such as Enhalus, Thalassia, Thalassodendron, Cymodocea, Halodule, and Syringodium, with an average value of density 198.03 individu/m2. While Bandengan waters was found 7 genus such as Enhalus, Thalassia, Thalassodendron, Cymodocea, Halodule, Syringodium and Halophila, with average value of density 457.1 individu/m2. The results showed that the average value of sedimentation rate in the Teluk Awur waters 438.74 g/m2/week, while the Bandengan waters 667.42 g/m2/week. The R2 value of relationship between Seagrass density with the sedimentation rate in the Teluk Awur waters 0.566. While the R2 of Bandengan waters 0.073. The Teluk Awur waters contain a little lanau sediment so it has a little sedimenation. Bandengan waters contain higher lanau sediment so it has more sedimentation.
Aplikasi Citra Sentinel-2 untuk Pemetaan Sebaran Material Padatan Tersuspensi Di Muara Sungai Wulan Demak Prasetiyo, Bayu Adi; Rochaddi, Baskoro; Satriadi, Alfi
977-2407769
Publisher : Departemen Ilmu Kelautan, Fakultas PerikanJurusan Ilmu Kelautan, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jmr.v8i4.25193

Abstract

ABSTRAK : Sungai Wulan yang terletak di Kabupaten Demak digunakan masyarakat sebagai jalur keluar dan masuknya kapal nelayan serta saluran pembuangan utama. Hal tersebut berdampak pada besarnya kandungan material padatan tersuspensi yang terdapat pada sungai. Pengamatan sebaran material padatan tersuspensi dibutuhkan untuk mengetahui pola sedimentasi dan penilaian kualitas air. Tujuan dari penelitian ini adalah untuk mengetahui sebaran material padatan tersuspensi di muara Sungai Wulan menggunakan metode pengindraan jauh. Data yang digunakan dalam penelitian ini adalah citra satelit Sentinel-2 dan konsentrasi material padatan tersuspensi hasil uji gravimetri. Pengolahan data menggunakan algoritma Lemigas (1997), Budhiman (2004), Parwati (2006), Laili (2015) dan Metode Regresi (Linear, Eksponensial dan Logaritmik). Hasil analisis data menunjukkan bahwa konsentrasi material padatan tersuspensi di sekitar muara relatif rendah, sedangkan konsentrasi yang tinggi terdapat di arah timur muara sungai atau di daerah yang berupa teluk. Algoritma yang memiliki nilai error terkecil adalah algoritma Metode Regresi dengan MRE sebesar 10,12% dengan nilai RMSE sebesar 4,3493. Berdasarkan hasil yang didapat, dapat disimpulkan jika algoritma Metode Regresi merupakan algoritma yang paling sesuai untuk pemetaan sebaran material padatan tersuspensi di muara Sungai Wulan, Demak. ABSTRACT : The Wulan River which located in Demak Regency is used by people as an entrance point for fishing boats and the main sewers. These have an impact on the amount of total suspended solid contained in the river. Observation about the distribution of total suspended solid is needed to determine sedimentation patterns and water quality assessments. The purpose of this study is to determine the distribution of total suspended solid at the Wulan River estuary using remote sensing method. The data used in this study is Sentinel-2 satellite imagery and the concentration of total suspended solid from gravimetric test. Processing data using Lemigas algorithm (1997), Budhiman (2004), Parwati (2006), Laili (2015) and Regression Method (Linear, Exponential and Logarithm). The results of data analysis show that the total suspended solids distribution at the estuary is relatively low, while the high consentration of total suspended solid is found at the east of the river estuary or in the area that form a bay. Algorithm that has the smallest error value is the regression algorithm with MRE value is 10.12% and RMSE value is 4.3493. Based on the results obtained, it can be concluded that the algorithm with regression method is the most suitable algorithm for mapping the distribution of total suspended solid at the mouth of the Wulan River, Demak.  
Sebaran Thermal Front Musiman di Wilayah Perairan Selat Madura Menggunakan Single Image Edge Detection Trinugroho Trinugroho; Alfi Satriadi; Muslim Muslim
Journal of Marine Research Vol 8, No 4 (2019): Journal of Marine Research
Publisher : Departemen Ilmu Kelautan, Fakultas PerikanJurusan Ilmu Kelautan, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (973.655 KB) | DOI: 10.14710/jmr.v8i4.24815

Abstract

Thermal front didefinisikan sebagai pertemuan antara dua masa air dengan karakteristik suhu yang berbeda sehingga membentuk gradien suhu. Thermal front merupakan salah satu proses oseanografi penting yang dapat mempengaruhi kondisi fisik, kimia, maupun biologi di laut. Tujuan dari penelitian ini adalah untuk mengetahui sebaran thermal front musiman di perairan Selat Madura, Jawa Timur. Deteksi thermal front dilakukan pada lapisan permukaan laut dengan menggunakan citra AquaMODIS untuk suhu permukaan laut. Citra AquaMODIS yang digunakan memiliki resolusi spasial sebesar 1 km x 1 km dan resolusi temporal selama satu hari. Metode yang digunakan untuk mendeteksi fenomena ini adalah metode Single Image Edge Detection (SIED) yang diperkenalkan oleh Cayula dan Cornilon pada tahun 1992. Metode ini menggunakan prinsip deteksi tepi piksel yang mempertimbangkan nilai gradien suhu dan pola arah dari piksel yang memiliki gradien suhu. Hasil yang diperoleh berupa sebaran spasial dan temporal fenomena thermal front di perairan Selat Madura. Sebaran temporal berdasarkan komposit harian dalam satu musim selama empat tahun dari tahun 2012 – 2016. Rata – rata kejadian thermal front tiap musim sebanyak 446 kali pada musim barat, 1893 kali pada musim peralihan I, 1038 kali pada musim timur, dan 2375 kali pada musim peralihan II. Penyebab utama kejadian front di perairan Selat Madura adalah akibat adanya arus eddy dan masukan masa air laut dari wilayah timur Selat Madura. Thermal front defined as an ecounter of two water masses which has different temperature (thermal) characteristics and create a thermal gradient. Thermal front is one of the most important oceanographic proceses that can make a significant impact to physical, chemical, and biological process in the ocean. The aim of this research is to understand seasonal thermal front distribution in Madura Strait, East Java. Thermal front was detected in the surface layer of water, using AquaMODIS for Sea Surface Temperature (SST). AquaMODIS image which used in this research has 1 km x 1 km spatial resolution and one day (24 hours) temporal resolution. Front detection in this research is using Single Image Edge Detection by Cayula Cornilon (1992). This method is using edge detection of pixel, considering the value of thermal gradient and pattern of the pixel edge. The result of this research is spatial and temporal distribution of thermal front in Madura Strait. Temporal distribution are based on composite result of daily front detection in seasonal range for four years from 2012-2016. Seasonal average of front occurence is 446 times in western season, 1893 times in Transition I, 1038 times in eastern season and 2375 times in Transition II. The main cause of front in Madura strait is eddy current and water masses ecounter from eastern area of Madura.
Pemodelan Perubahan Dasar Perairan (Bed Level Change) di Pantai Moro, Kabupaten Kendal Muhammad Chiesa Fathirayan; Hariyadi Hariyadi; Alfi Satriadi
Journal of Marine Research Vol 12, No 2 (2023): Journal of Marine Research
Publisher : Departemen Ilmu Kelautan, Fakultas PerikanJurusan Ilmu Kelautan, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jmr.v12i2.31252

Abstract

Pantai Moro, Gubugsari, merupakan salah satu daerah wisata yang potensial di Kabupaten Kendal. Pantai Moro memiliki menara pandang yang menjadi ciri khas. Faktor alam berupa perubahan dasar perairan di Pantai Moro perlu diperhatikan untuk menunjang kegiatan masyarakat. Tujuan dari penelitian ini adalah untuk mengetahui sebaran jenis sedimen dan perubahan dasar perairan berdasarkan hasil model. Pemodelan untuk mengetahui perubahan dasar perairan dilakukan menggunakan perangkat lunak MIKE21 modul Sand Transport dengan memasukkan data-data seperti batimetri, pasang surut, arus, gelombang, angin dan karakteristik sedimen dasar. Pemodelan dilakukan selama satu bulan setiap musim. Sedimen dasar di Perairan Pantai Moro berupa pasir, lanau, pasir lanauan dan lanau pasiran pada daerah pantai dan lanau pada daerah laut. Hasil pemodelan menunjukkan terjadi sedimentasi pada daerah dekat pantai sebesar 0,0945 m - 0,0005 m, dan terjadi erosi pada daerah muara sebesar 0,005 m.   Moro Beach, Gubugsari District is one of potential tourism areas in Kendal Regency. Moro Beach has sight tower, which is the hallmark of the area. Natural factor in the form of bed level changes is need to be considered to support community activities. The purpose of this study was to determine the distribution of sediment types and the bed level change of Moro Beach based on model result. The model is using MIKE 21 software ; Sand Transport (ST) module with input data of bathimetry, tides, current, waves, wind and seabed sediment. Sediment of Moro Beach is sand, silt, sandy silt and silty sand in beach area and silt in sea area. The result of modeling is indicates the sedimentation process near the beach with a value of 0,0945 m - 0,0005 m and erosion process in the estuary area with a value of 0,005 m.
Co-Authors Ade Firdaus Triagusta Afrianto Tua Sinaga Agus Anugroho D.S. Agus Anugroho Dwi S.P, Agus Anugroho Ahmad Gulbuddin Dzul Qarnain Akbar Nurrahman Putra Alan Wardheni Ali, M. Noor Anang Joko Sadono Andi Dwi Pramulya Angelica, Anastasia Grace Anggardha Ayu Pratiwi Anugrah Riskel Shabari Ari Soebekti Ari Widyawati Aris Ismanto Azis Rifai Bagus Rahmattullah Dwi Angga Baskoro Rochaddi Bayu Adi Prasetiyo Bayu Priyono, Bayu Chesya Sera De Claresya Chrisna Adhi Suryono Dani Agusto Daniel Giovanni Sihotang Dayinta Andayani Delianis Pringgenies Delyuzar Ilahude Denny Nugroho Denny Nugroho Sugianto Devi Verawati Gusman Dinda Mazeda Dinny Anjang Sari Dwi Haryo Ismunarti Edi Wibowo Kushartono Eka Bathin Putra Elis Indrayanti Endang Sri Susilo Erdian, Oldy Ervia Yudiati Eza Rendy Putra Fajri, Muhamad Faqih Falah As’adi Bisyri Franto Novico Gaol, Hadimas Lumban Genda Priherdika Gentur Handoyo Gentur Handoyo Gisela Dinda Kresteva Gita Praspa Ramdhani Gunawan, Albert Hadyan Rafdi Kamarz, Hadyan Rafdi Hanah Khoirunnisa Hariadi Hariadi Hariadi Hariadi Hariadi, Ardian Hariyadi Hariyadi Harmon Prayogi Haryadi Haryadi Hediarto, Mohamad Abror Heryoso Setiyono Heryoso Setyono Iman, Hudiya Izzatul Indra Budi Prasetyawan Irwan Hidayatullah, Irwan Irwani Irwani Ita Riniatsih Jarot Marwoto Jarot Marwoto Karunia Lasmarito Pintubatu Kunarso Kunarso Lili Sarmili Lilik Maslukah Ma'ariq Badrutamam S. Maemonah, Maemonah Maharanni Catherinna Mangkoewijoto, Dipa Yudhayana Melanie Rizky Hanuransyah Mohamad Ihsan Wijaya Muh Yusuf Muhamad Azhar Fathurahman Muhammad Ali Agus Masrukhin Muhammad Alif Achyansyah Muhammad Chiesa Fathirayan Muhammad Helmi Muhammad Helmi Muhammad Zainuri muharam, Iqbal Muslim Muslim Ni Komang Sri Andayani Nugroho Agus D Nur Kholik Kurniana Putra Nursanti Nursanti Ory Kristanto Petrus Subardjo Petrus Subarjo Prasetiyo, Bayu Adi Prasetyo, Damar Aji Purwanto Purwanto Purwanto Purwanto Raden Ario Redyansyah, Rio Restie AIK Ria Azizah T.N. Rikha Widiaratih Rini Pramesti Rizky Bagus Ardianto Salman Asatidz Setiya Kusuma Anggraeni, Setiya Kusuma Siddhi Saputra Siddhi Saputro Sitepu, Rahmat Saleh Soca Ratna Firdaus Sugeng Widada Sutarno Eko Arvianto, Sutarno Eko Tagore, Rafa Fahrezi Taohid, Rizki Adittio Teo Andri Saputra Tiurma S Tri Abdul Hidayat Trianne, Sarah Trinugroho Trinugroho Tulus Aldrian Siregar Warsito Atmodjo Yeni Martina Navratilova Pasaribu Yodha Pradipta Yoga Yuniadi Yulius Yulius Yuniastuti, Florentina Chandra Yuwono Wikan Driyogo