JURNAL ENGGANO

Variasi Musiman Sea Level Anomaly di Wilayah Perairan Indonesia

Julis Dani Haryo, Lizalidiawati Lizalidiawati, Irkhos Irkhos, Suhendra Suhendra — Sun, 29 Sep 2024 00:00:00 +0000

Indonesia's territory is located between two vast oceans, namely the Pacific and Indian Oceans as well as the two continents of Australia and the continent of Asia. As a result, Indonesia's regional climate is directly influenced by these geographical conditions. As is known, Indonesia experiences the Northwest Monsoon and Southeast Monsoon. The seasonal variations that occur include part of the aim of this research, namely to identify seasonal variations in sea surface anomalies (SLA) in three regions of Indonesia representing western, central and eastern waters using altimetry satellite image data. The coordinates of these three areas, namely, represent parts of the West Sumatra Sea (1°S – 3°S, 95°E – 100°E), Makassar Strait (5°S- 8°S, 119°E- 25°E), and the Banda Sea (5°S – 8°S, 125°E – 109°E). The data used for 30 years (1993-2022) is in the form of monthly average SLA data and processed using Panoply software to display the SLA distribution in each area as well as the SLA Time Series in the three regions. The research results show that the highest sea level rise occurred in area A (Western waters of Sumatra) with an SLA of 1.4 m with a rate of increase ranging from 0.5-1.4 m/year. In area B (Banda Sea), the SLA obtained is 1.2 m with an increase rate ranging from 0.7-1.2 m/year. Meanwhile in Area C (Makassar Strait) it is 1.3 m with an increase rate ranging from 0.7-1.3 m/year.

Keywords: Sea Surfalce Height, Season variation, west, east, and middle region.

Pertumbuhan Rumput Laut Kappaphycus alvarezii (Doty, 1985) dengan Metode Lepas Dasar

Muhammad Rifky Prayudha, Rini Pramesti, AB Susanto — Sun, 29 Sep 2024 00:00:00 +0000

Environmental factors have affected seaweed cultivation. Productivity can be increased by using the right method. Seaweed production is related to brightness and photosynthetic processes which are affected by planting depth. This study aims to examine the effect of differences in depth on the growth rate of K. alvarezii with the off-bottom cultivation method in the waters of Lontar Village, Serang Regency, Banten Province. Randomized Block Design was used as the experimental design in this study. Cultivation depth of 30 cm, 50 cm and 70 cm were used as different treatments, each with three groups and 5 replications. The growth of sample weight was observed every week for six weeks as the main parameter. Water quality (temperature, salinity, brightness, pH, current velocity, nitrate, phosphate and dissolved oxygen) was observed as another parameter. The results showed that weight growth is influenced by the depth of cultivation. The 30 cm depth has the highest growth rate with an absolute growth of 890 grams and a specific growth rate of 2.85% per day.

Keywords : Kappaphycus alvarezii, depth, growth rate

Desain Hydrolic System With Twin Brush Kart Sebagai Sarana Penunjang Percepatan Project Ship Maintenence

Mon, 30 Sep 2024 00:00:00 +0000

ABSTRACT

One of the tools that can assist in the maintenance process of a ship before it enters a dry dock is an underwater ship hull cleaner. The existing tools currently used are not yet widely available across Indonesia. Therefore, this research aims to plan the development of an underwater ship hull cleaner named the Twin Brush Kart. The objective is to determine an efficient system and design. The methodology involves collecting data on the number of shipyards and ships in Indonesia, as well as existing underwater ship hull cleaners. From the available hull cleaner data, this research adopts a hydraulic system. The hydraulic system offers advantages such as flexibility, versatility, and efficiency. The resulting design is user-friendly, with dimensions of 70 cm length, 55 cm width, and 16.7 cm height, and includes a control interface for the user. Additionally, the planned system is straightforward for users to understand, allowing for quick learning of the Twin Brush Kart. Based on the planning results, the specifications include a diesel engine with 14.55 kW of power, a hydraulic pump with a flow rate of 40.1 lpm and a working pressure of 185 bar, and a rotary actuator with a displacement of 19.9 cc and a rotational speed of 1000 RPM.

Keywords: Hull, underwater cleaner, hydraulic system

Pola Pertumbuhan Kerang Lokan Geloina erosa, Solander 1786 di Muara Jenggalu Kota Bengkulu

Mon, 30 Sep 2024 00:00:00 +0000

Kerang lokan Geloina erosa merupakan salah satu kelompok Bivalvia yang hidup dan berkembang di Ekosistem Mangrove. Kerang ini telah dimanfaatkan oleh penduduk sekitar sebagai biota konsumsi dan memiliki kandungan gizi yang tinggi. Salah satu daerah penghasil kerang lokan di Kota Bengkulu adalah Muara Jenggalu, terletak di Jalan Jenggalu Kelurahan Lingkar Barat Kota Bengkulu. Permintaan masyarakat yang cenderung meningkat setiap tahun menyebabkan meningkatnya eksploitasi terhadap kerang lokan. Pemanfaatan kerang lokan dieksploitasi secara langsung di ekosistemnya yaitu ekosistem mangrove. Pengambilan kerang lokan secara terus menerus dan banyaknya aktivitas manusia di sekitar kawasan Muara Jenggalu dikhawatirkan dapat mengakibatkan terjadinya penurunan ketersediaan stok kerang lokan di ekosistem mangrove Muara Jenggalu. Penelitian ini bertujuan untuk menganalisis hubungan panjang berat dan nisbah kelamin kerang lokan di Muara Jenggalu Kota Bengkulu. Pertumbuhan kerang lokan di Muara Jenggalu bersifat allometric negative (<3) dimana pertumbuhan panjang cangkang lebih dominan daripada pertumbuhan berat. Persentase jumlah kerang lokan berjenis kelamin jantan yaitu 61,96% dan berjenis kelamin betina 38,04%.

Variasi Musiman Tinggi Gelombang Laut di Perairan Pulau Enggano Provinsi Bengkulu

Jeniu Chinci, Lizalidiawati Lizalidiawati, Suhendra Suhendra, Anjasman Anjasman — Mon, 30 Sep 2024 00:00:00 +0000

Enggano Island is one of Indonesia's outermost islands located in the waters west of Sumatra. Enggano Island is directly adjacent to the vast and deep Indian Ocean so that the waters are very dynamic. One of them is known that the sea waves in these waters are very volatile. This study aims to find out the seasonal variation of sea wave height in the waters of Enggano Island, Bengkulu Province. This study uses primary data in the form of sea wave height measured at Kaana Beach and secondary data for 3 years (2021-2023) in the form of monthly average wind direction and speed, temperature and density data obtained from https://data.marine. copernicus.eu/viewer/expert?view=layers&dataset=GLOBAL_ANALYSISFORECAST_PHY_001_024, sea wave height data obtained from https://data.marine.copernicus. eu/viewer/expert?view=layers&dataset=GLOBAL_ANALYSISFORECAST_WAV_001_027. Data processing uses Python Anaconda 3 software for 2D display and Microsoft Excel for time series display. The methods used in this study are descriptive and quantitative methods. The results of the study show that the sea wave height in the waters of Enggano Island varies seasonally, it can be seen that the maximum sea wave height occurs in the eastern season in August with a value of 1.5-3 m with a wind direction and speed of 5-6 m/s and 7 m/s in the southern area of the island, while the minimum wave height occurs in the western season in December with a value of 1-2 m with a wind direction and speed of 1-2 m/s blowing towards the North and West of the island.

Keywords : Enggano Island, seasonal variation, high sea waves, wind speed