Pangandaran rocky shores have a unique ecosystem and a variant of invertebrate organisms such as mollusk from the gastropod class. This study aims to analyze the biodiversity of gastropods on the rocky shore of Karapyak beach. This research consists of 5 stations. The quadrant set by 1 m x 1 m vertically toward the sea. The result found 773 individuals scattered in nine families. The family of Neritidae dominated (43%), followed by family cyprinoids with 6.3%. Nerita plicata is a species found to dominate in every station with an average abundance (256 ± 10) and/m2. Using the Bray-Curtis cluster analysis, showed variations in the distribution and abundance of different gastropods vertically into the ocean and uniformly distributed horizontally to the shore. Substrate and tidal are the main variables in the spatial distribution of gastropods in the Karapyak beach.

Tides are the rise and fall of sea level caused by the attraction of objects in the sky, especially the moon and sun, to the mass of seawater on earth. Tidal research is useful for providing information about the components and types of tides and predicting tides and for mitigating natural disasters. Tidal measurements were carried out in the Nasik Strait, Bangka Belitung using the Valeport 106 tool. Tidal data was processed using the Admiralty Method. The Admiralty method is a method used to calculate tidal harmonic constants from observations of water levels. With this method, it is possible to know the amplitude and phase difference of the tides, the value of the Formzahl number, and the type of tide. From the results of data processing and analysis, the value of the Formzahl number in the waters of the Nasik Strait is 11,454 and the tidal type is a single daily tidal type that only occurs at one high tide and one low tide in one day.Keywords: tides; tidal types; admiralty method; formzahl numberAbstrakPasang surut adalah naik turunnya muka air laut yang disebabkan oleh gaya tarik benda-benda di langit, terutama bulan dan matahari terhadap massa air laut yang ada di bumi. Penelitian pasang surut bermanfaat untuk memberikan informasi mengenai komponen dan tipe pasang surut serta  memprediksi pasang surut serta untuk mitigasi bencana alam. Pengukuran pasang surut dilakukan di Perairan Selat Nasik, Bangka Belitung dengan menggunakan alat Valeport 106. Data pasang surut diolah dengan menggunakan Metode Admiralty. Metoda Admiralty merupakan metode yang digunakan menghitung konstanta harmonik pasang surut dari pengamatan ketinggian air. Dengan metoda ini dapat diketahui  amplitudo dan beda fase pasang surut, nilai bilangan Formzahl dan tipe pasang surutnya. Dari hasil pengolahan dan analisa data diperoleh nilai bilangan Formzahl di perairan Selat Nasik yaitu 11,454 dan tipe pasang surut adalah tipe pasang surut harian tunggal yang hanya terjadi satu kali pasang dan satu kali surut dalam satu hari.Kata Kunci: pasang surut; tipe pasang surut; metode admiralty; bilangan formzahl

Pada umumnya pembuatan garam secara tradisional menggunakan teknologi evaporasi air laut   memerlukan waktu 20 hari per panen garam, sedangkan dengan metode Maduresse Berisolator memerlukan waktu 12 hari per panen garam. Tujuan penelitian ini adalah untuk melakukan inovasi teknologi evaporasi air laut dengan uji coba aplikasi teknologi tepat guna dalam percepatan pembuatan garam dengan Metode Sprinkle Bertingkat. Penelitian ini dilakukan selama 3 bulan mulai bulan Agustus sampai dengan bulan Oktober 2019 sebanyak 30 kali ulangan dan menghasilkan data rata – rata 3 oBe menjadi 9,78 oBe per hari.  Hasil penelitian ini dengan Metode Sprinkle Bertingkat dalam waktu 6 hari menghasilkan kristal garam atau lebih cepat 6 hari per panen, jika dibandingkan dengan Metode Maduresse Berisolator. Percepatan pembuatan garam ini terjadi karena adanya inovasi teknologi dengan menambahkan alat berupa sprinkle yang berfungsi menyemprotkan air laut ke udara sehingga mempercepat terlepasnya H2O dari air laut dan mempercepat terbentuknya kristal garam. Dengan demikian dapat disimpulkan bahwa Metode Sprinkle Bertingkat dapat diterapkan untuk mempercepat terbentuknya kristal garam, sehingga metode ini direkomendasikan sebagai inovasi teknologi dalam meningkatkan produksi garam.

Mangroves are forest vegetation that grows between tidal lines so that mangrove forests are also called tidal forests. Mangrove ecosystems have high biodiversity. The mangrove ecosystem has a physical function to protect the coast from abrasion and erosion, this ecosystem also has ecological and economic value. The purpose of this study was to determine the condition and extent of mangrove distribution on the coast of Karawang Regency. The research was carried out on the coast of Karawang Regency from March to June 2021. The data used is primary data by directly observing the research location and secondary data using remote sensing data from the Landsat 8 satellite. Image data processing and analysis is carried out using the NDVI (Normalized Difference Vegetation Index) method which can create a boundary between mangrove and non-mangrove. With this method, it can be seen the changes in the mangrove distribution area from year to year. The results of data processing and analysis show that in 2013 the distribution of mangroves on the coast of Karawang Regency has an area of ​​207.88 km2, in 2016 it has an area of ​​357.22 km2 and in 2020 its area is 237.61 km2.

Cijulang River is one of the leading ecotourism objects in Pangandaran, West Java Province, Indonesia. However, the river has a variety of activities that can increase the water pollution in the river such as Green Canyon cliffs tourism, ecotourism of mangrove conservation, housing, and industrial siting. Macrobenthos is one of the bio-indicators that can assess the rate of water pollution in rivers, especially their organic pollutants. Therefore, this research aims to determine water pollution status in Cijulang River Tourism by comparing various biotic indices. The study was conducted at four site sampling locations from upstream to downstream in the rainy season period and dry season period using different methods namely, line transect model, water quality assessment by biological indexing (diversity, species dominant, and family biotic), species deficit, and organic measurement. The research showed 5873 macrobenthos and divided into 27 species with an average abundance of 167 ind.m-2 and are mainly dominated by gastropod species Faunus ater (40%). They are extreme species that can live in high organic pollution and water salinity. This divided the research of quality water assessment of Cijulang River into three categories as follows: slightly polluted (score 36-46) at Green Canyon site, moderately polluted (score 50-60) at Boat Shelter and Muara Cijulang location, and highly polluted (score 66) at Nusawiru site.Keywords:RiverBio-indicatorOrganicAquatic pollution