HYDRODYNAMICS MODELING IN KENDARI BAY, SOUTHEAST SULAWESI, INDONESIA

Kendari Bay is coastal water in the center of the capital city of Southeast Sulawesi province. It is shaped like a pocket with a narrow mouth and there is an estuary of a large river, namely the Wanggu river, which makes the dynamics of its waters very interesting to study. The focus of the study is the hydrodynamic factors in the Kendari Bay and Wanggu River areas. This study aims to examine the hydrodynamic conditions of Kendari Bay, mainly due to the existence of reclamation and the influence of the Wanggu River which has not been studied previously. This research method uses a two-dimensional model based on bathymetric data, tides, and the flow of the Wanggu River with a simulation time of 15 days (1 March to 15 March 2020). The modeling results were then verified with PUSHIDROSAL tidal elevation data showing an RMSE value of 0.07 indicating that the model was well constructed. The mixed tidal type with a tendency to double daily is the tidal type of Kendari Bay waters based on the Formzahl number value of 0.51. The current pattern generally moves in and out from east to west and vice versa with a varying elevation range following spring conditions of 1.75 m. The maximum tidal speed is 0.1784 m/s and the minimum value is 0.0057 m/s which is shown in the sample results of the model when the hing to low tide, and low to high tide. The results of the hydrodynamic modeling show that the current velocity increases when passing through a narrow path, namely the bay estuary and river estuary. The existence of the reclamation area affects the changes in the velocity of the current which is significantly larger and the direction of the current that undergoes a deflection follows the shape of the reclamation area. The current direction is to the southeast and then turns towards the northeast when low to high tide and eastward then turns towards the northeast when the high to low tide spring conditions compared to research before the reclamatio

Land Cover Classification Assessment Using Decision Trees and Maximum Likelihood Classification Algorithms on Landsat 8 Data

Classification technique on remote sensing images is an effort taken to identify the class of each pixel based on the spectral characteristics of various channels. Traditional classifications such as Maximum Likelihood are based on statistical parameters such as standard deviation and mean, which have a probability model of each pixel in each class. While the object-based classification method, one of which is the Decision Trees, is based on rules for each class with mathematical functions. This study compares the Decision Trees and Maximum Likelihood algorithms for land cover classification in the Surabaya and Bangkalan areas using Landsat 8 data. This research begins with creating Regions of Interest (ROIs) and Rules on images with greater than and less than functions for Decision Trees. The ROIs test was carried out using the Separability Index and matching each class using the Confusion Matrix. The experimental results show that the accuracy value resulting from the Confusion Matrix calculation is 90.48%, with a Kappa Coefficient Value of 0.87. The Decision Trees method produces land cover nigher to the actual condition than the Maximum Likelihood method. The difference in the class distribution of the two ways is not significant. This study is limited because the validation uses manual interpretation results. Future research is expected to use the large-scale classification results from the relevant agencies to verify the classification results and use field data, larger samples of ROIs, and the use of high-resolution imagery in order to improve the classification results

DISTRIBUTION OF SALINITY AND TEMPERATURE IN MUSI ESTUARY: USING VERTICAL SALINITY GRADIENT FOR ESTUARY CLASSIFICATION ZONE

Muara Musi merupakan muara sungai Telang dan Musi yang berbatasan langsung dengan Selat Bangka. Pada saat pasang (surut) kita melihat distribusi salinitas meningkat (menurun) yang diketahui melalui distribusi vertikal menggunakan CTD (Conductivity Temperature Depth). Diagram TS (Temperature-Salinity) digunakan untuk melihat karakteristik massa air di daerah penelitian. Metode DIVA (Data-Interpolating Variational Analysis) digunakan untuk interpolasi dan visualisasi data dari data vertikal dan spasial temperatur, salinitas dan densitas. Klasifikasi zona muara Musi diidentifikasi berdasarkan nilai sebaran salinitas yang memperhitungkan pertukaran salinitas yang bersirkulasi pada saat pasang dan surut. Densitas massa air secara signifikan dipengaruhi oleh salinitas yang terbukti bergradasi. Sementara distribusi suhu tidak berubah secara signifikan dengan kedalaman, distribusi spasial menunjukkan bahwa suhu di estuari lebih rendah daripada di daerah hulu dan laut. Distribusi spasial salinitas menunjukkan bahwa salinitas tinggi memasuki muara menuju sungai lebih jauh pada saat pasang dari pada saat surut. Distribusi salinitas berkisar antara 0,5–30 psu dan suhu antara 29–33 ℃ dari bagian horizontal dan vertikal. Pola sebaran salinitas di muara sungai Musi diidentifikasi, terdiri dari tiga zona yang mewakili kondisi salinitas di daerah penelitian, yaitu zona Polyhaline, Mesohaline, dan Olygohaline.Musi estuary is the mouth of the Telang and Musi rivers directly adjacent to the Bangka Strait. During flood (ebb) we see the distribution of salinity increases (decreases) which is known through the vertical distribution using CTD. The TS diagram is used to see the water mass characteristics the study area. Data-Interpolating Variational Analysis (DIVA) method is used to interpolate and visualize data from vertical and spatial temperature, salinity and density data. The classification of the Musi estuary zone is identified based on the value of the distribution of salinity, which considers the exchange of circulating salinity at flood and ebb. The density of the water mass is significantly affected by the proven graded salinity. While the temperature distribution does not change significantly with depth, the spatial distribution indicates that the temperature in the estuary is lower than in the upstream and ocean areas. The spatial distribution of salinity indicates that high salinity enters the estuary towards the river further at flood than at ebb. Salinity distribution ranges from 0.5 to 30 psu and temperatures between 29 and 33 oC from horizontal and vertical sections. The pattern of salinity distribution in the Musi river estuary was identified, consisting of three zones representing salinity conditions in the study area, namely the Polyhaline, Mesohaline, and Olygohaline zones

Studi Karakteristik Oseanografi Sebagai Rekomendasi Waktu Penanaman Mangrove (Studi Kasus: Pulau Dompak)

ABSTRAKDegradasi ekosistem mangrove menyebabkan banyak kerugian baik dalam hal pengelolaan jasa lingkungan maupun secara finansial. Penanaman mangrove sendiri merupakan bentuk restorasi guna menyelamatkan penurunan luasan areal mangrove. Dinamika oseanografi merupakan faktor penentu untuk peningkatan keberhasilan dalam kegiatan restorasi ekosistem mangrove. Pulau Dompak tercatat sebagai kawasan Provinsi Kepulauan Riau dengan areal tutupan ekosistem mangrove yang cukup luas namun tergolong tinggi tingkat pemanfaatannya. Penelitan ini bertujuan untuk merekomendasikan waktu terbaik dalam penanaman mangrove dengan melakukan studi karakteristik oseanografi. Metode yang digunakan pada penelitian ini yaitu berupa pemetaan data karakteristik oseanografi dan deskriptif analisis. Hasil yang didapat pada empat parameter oseanografi berupa suhu, salinitas, arus dan pasang surut masing-masing menunjukan perubahan yang tidak terlalu signifikan dan tergolong baik untuk dilakukan penanaman mangrove. Rekomendasi waktu penanaman mangrove terbaik yaitu pada kondisi kecepatan arus terendah yaitu pada Musim Peralihan I.Kata kunci : Musim Peralihan I, Penanaman mangrove, Pulau Dompak, OseanografiABSTRACTDegradation of mangroves causes many losses both in terms of management of environmental services and financially. Mangrove planting is a restoration to save decreasing areas of mangrove. Oceanography is a determining factor for increasing success in mangrove ecosystem restoration activities. Dompak Island is listed as an area of the Riau Archipelago Province with a relatively wide area of mangrove ecosystem cover but a relatively high level of utilization. This research aims to recommend the best time for planting mangroves by conducting a study of oceanographic characteristics. The method used in this study is in the form of mapping data on oceanographic characteristics and descriptive analysis. The results obtained for the four oceanographic parameters, namely temperature, salinity, currents, and tides each show not too significant changes and classified as good for planting mangroves. The recommendation for the best time to plant mangroves is at the lowest current velocity, namely during the Transitional Season I.Keyword : Dompak island, Planting mangrove, Oceanography, Transitional Season

Usaha Pengolahan Buah Mangrove Xylocarpus sp (Nyirih) Menjadi Lulur Kecantikan Di Desa Brengkok, Kecamatan Brondong, Kabupaten Lamongan, Jawa Timur

Ekosistem mangrove memiliki keanekaragaman dan kegunaan, antara lain sebagai penghasil bahan organik, tempat pemijahan berbagai jenis udang, ikan dan moluska. Sementara masyarakat tidak begitu memahami dan mengetahui tentang pemanfaatan dari buah mangrove. Pemanfaatan buah mangrove ini sudah banyak dimanfaatkan di Semarang, khususnya didaerah pesisir pantai yang terdapat ekosistem mangrove. Bahkan diluar Jawa seperti didaerah Maluku sudah memanfaatkan buah mangrove tersebut. Sebagai contoh yaitu yang dilakukan oleh Dosen – dosen FPIK Universitas Khairun Ternate, Maluku Utara, Indonesia. Didalam pengabdiannya disebutkan kegunaan buah Xylocarpus Sp (Nyirih) adalah untuk mengatasi kulit kusam, karena didalam buah tersebut mengandung anti oksidan. Sehingga sudah ada beberapa produk lulur kecantikan dari buah Xylocarpus Sp (Nyirih). Pemanfaatan dari buah Xylocarpus Sp (Nyirih) yang dijadikan sebagai lulur kecantikan ternyata sudah banyak dilakukan oleh masyarakat sekitar hutan mangrove, berbentuk prodak (bubuk) dan dipasarkan. Pemasaran prodak tersebut melalui media online dan offline dengan harga per item Rp 25.000/100g. Hal tersebut dapat menjadi peluang usaha bagi masyarakat di Desa Brondong. Metode yang yang dilakukan yaitu dengan pendampingan bagi kelompok baru, memberikan pelatihan pengolahan prodak dan pemasaran via online dan offline. Secara kualitatif, hasil dari pelatihan memberikan skill dan pemahaman bagi kelompok, sehingga dapat diterapkan dan berguna bagi peningkatan pendapatan kelompok di Desa Brondong