http://repository.ipb.ac.id/handle/123456789/110 2026-10-11T12:32:32Z 2026-10-11T12:32:32Z Annisa, Riftia Ishab http://repository.ipb.ac.id/handle/123456789/180041 2026-10-05T01:06:39Z 2026-01-01T00:00:00Z

Hubungan Antara Kandungan Nitrat dan Fosfat Dengan Kelimpahan Fitoplankton di Perairan Pulau Harapan, Kepulauan Seribu a.n RIFTIA ISHAB ANNISA (C5401221069) Annisa, Riftia Ishab Abstrak: Perairan Pulau Harapan, Kepulauan Seribu, menghadapi tekanan antropogenik yang berpotensi meningkatkan konsentrasi unsur hara dan memicu eutrofikasi. Penelitian ini bertujuan menganalisis kandungan nitrat dan fosfat, mengidentifikasi jenis dan kelimpahan fitoplankton, serta mengkaji hubungan keduanya. Pengambilan data dilakukan pada Februari, Mei, Agustus, dan November 2025 di empat Stasiun. Nitrat dan fosfat dianalisis secara spektrofotometri, sedangkan fitoplankton diidentifikasi dan dihitung menggunakan Sedgwick–Rafter Counting Chamber. Konsentrasi nitrat berkisar 0,018–0,070 mg/L dan fosfat 0,010–0,023 mg/L. Nitrat melampaui baku mutu selama seluruh periode pengamatan, sedangkan fosfat mulai Mei. Fitoplankton didominasi Bacillariophyceae, dengan 7–18 taksa dan kelimpahan 1,0–9,8 × 106 sel/L. Fosfat menunjukkan hubungan lebih kuat terhadap kelimpahan fitoplankton (R² = 0,1555) dibandingkan nitrat (R² = 0,0079). Rasio Redfield menunjukkan nitrat sebagai unsur hara pembatas. Abstract: Pulau Harapan, Kepulauan Seribu, is subject to anthropogenic pressures that may increase nutrient concentrations. This study aimed to determine nitrate and phosphate concentrations, identify phytoplankton composition and abundance, and their relationships. Data were collected in February, May, August, and November 2025 at four stations. Nitrate and phosphate were analyzed spectrophotometrically, while phytoplankton were enumerated using a Sedgwick–Rafter Counting Chamber. Nitrate ranged from 0.018–0.070 mg/L and phosphate from 0.010–0.023 mg/L. Nitrate exceeded the seawater standard throughout observations, whereas phosphate exceeded the standard from May onward. Phytoplankton were dominated by Bacillariophyceae, with 7–18 taxa and abundances of 1.0–9.8 × 106 cells/L. PCA explained 51.68% of variance. Regression showed a stronger relationship between phosphate and abundance (R² = 0.1555) than nitrate (R² = 0.0079). The N:P ratio remained below 16, indicating nitrate limitation.

2026-01-01T00:00:00Z Alfian, Muhammad Rizky http://repository.ipb.ac.id/handle/123456789/180034 2026-09-29T23:13:48Z 2026-01-01T00:00:00Z

Deteksi Invertebrata Laut pada Ekosistem Lamun menggunakan eDNA Metabarcoding di Pantai Sanur, Bali Alfian, Muhammad Rizky Ekosistem lamun Pantai Sanur, Bali mengalami tekanan antropogenik akibat aktivitas wisata dan limbah domestik yang berpotensi memengaruhi komunitas invertebrata laut. Penelitian ini bertujuan mengidentifikasi keanekaragaman spesies menggunakan metode environmental DNA (eDNA) metabarcoding dengan penanda gen 16S rRNA. Sampel air dianalisis melalui ekstraksi DNA, PCR (Polymerase Chain Reaction), Next-Generation Sequencing (NGS), serta analisis QIIME 2 dan BLAST (Basic Local Alignment Search Tool). Hasil penelitian mengidentifikasi 16 spesies dari 21 Operational Taxonomic Units (OTUs) yang mewakili 9 kelas dan 7 filum. Nilai Indeks Shannon-Wiener sebesar 2,03–2,15 menunjukkan keanekaragaman sedang. Metode eDNA metabarcoding terbukti efektif untuk mendeteksi keanekaragaman invertebrata laut pada ekosistem lamun.; The seagrass ecosystem at Sanur Beach, Bali, is subject to anthropogenic pressure from tourism activities and domestic waste, which may affect marine invertebrate communities. This study aimed to identify species diversity using the environmental DNA (eDNA) metabarcoding method with the 16S rRNA gene marker. Water samples were analyzed through DNA extraction, PCR (Polymerase Chain Reaction), Next-Generation Sequencing (NGS), and analysis using QIIME 2 and BLAST (Basic Local Alignment Search Tool). The results identified 16 species from 21 Operational Taxonomic Units (OTUs), representing 9 classes and 7 phyla. Shannon-Wiener Index values ??ranging from 2.03 to 2.15 indicated moderate diversity. The eDNA metabarcoding method proved effective for detecting marine invertebrate diversity in the seagrass ecosystem.

2026-01-01T00:00:00Z Ramadhana, Naurah Alifah http://repository.ipb.ac.id/handle/123456789/179982 2026-09-28T07:38:45Z 2026-01-01T00:00:00Z

Model Sebaran Tumpahan Minyak di Lintas Utara Selat Malaka Ramadhana, Naurah Alifah Selat Malaka bagian utara merupakan jalur pelayaran padat dan rentan terhadap risiko tumpahan minyak, namun studi pemodelan trayektori tumpahannya masih terbatas. Penelitian ini bertujuan memodelkan sebaran dan nasib tumpahan minyak hipotetik di lintas utara Selat Malaka menggunakan General NOAA Operational Modeling Environment (GNOME), dengan data arus dan pasang surut dari Copernicus Marine Service (CMEMS) serta data angin dari ERA5 sebagai gaya penggerak, yang divalidasi terhadap data observasi arus, pasut, dan angin primer. Simulasi dilakukan pada dua jenis minyak, Arabian Light dan Swallow Ace, mewakili musim utara dan musim selatan pada empat kondisi fase pasut. Hasil validasi menunjukkan keandalan tinggi pada data arus dan pasut, sedangkan data angin memiliki keterbatasan akibat resolusi data observasi. Pola arus dan angin musiman memengaruhi luas dan arah sebaran tumpahan, dengan musim selatan menghasilkan sebaran lebih luas namun musim utara menghasilkan fraksi terdampar lebih tinggi. Nasib minyak Arabian Light didominasi oleh evaporasi, sedangkan Swallow Ace didominasi oleh fraksi terapung akibat sifat persisten dan viskositas tinggi. Analisis tumpang susun terhadap ekosistem pesisir menunjukkan risiko lebih tinggi terhadap terumbu karang dibandingkan hutan mangrove, dengan risiko meningkat pada musim selatan.; The northern Strait of Malacca is a heavily trafficked shipping lane vulnerable to oil spill risk, yet trajectory modeling studies for this region remain limited. This study aims to model the dispersion and fate of a hypothetical oil spill in the northern Strait of Malacca using the General NOAA Operational Modeling Environment (GNOME), by current and tidal data from the Copernicus Marine Service (CMEMS) and wind data from ERA5, validated against primary current, tidal, and wind observations. Simulations were conducted for two oil types, Arabian Light and Swallow Ace, representing the northeast and southwest monsoon seasons under four tidal phase conditions. Validation results showed high reliability for current and tidal data, while wind data showed limitations due to the resolution of observational data. Seasonal current and wind patterns influenced the extent and direction of the spill, with the southwest monsoon producing wider dispersion while the northeast monsoon produced a higher stranded fraction. Arabian Light's fate was dominated by evaporation, whereas Swallow Ace was dominated by the floating fraction due to its persistent and highly viscous nature. Overlay analysis with coastal ecosystems indicated higher risk to coral reefs than to mangrove forests, with risk increasing during the southwest monsoon.

2026-01-01T00:00:00Z Azizah, Hafidloh Nur http://repository.ipb.ac.id/handle/123456789/179815 2026-08-24T03:41:20Z 2026-01-01T00:00:00Z

Biodiversitas plankton pada kawasan KKP3K KDPS Kabupaten Berau, Kalimantan Timur Azizah, Hafidloh Nur Kawasan Konservasi Pesisir dan Pulau-Pulau Kecil (KKP3K) Kepulauan Derawan dan Perairan Sekitarnya (KDPS) memiliki keanekaragaman hayati yang tinggi, namun informasi mengenai biodiversitas plankton masih terbatas. Penelitian bertujuan mengidentifikasi komposisi, kelimpahan, indeks biodiversitas fitoplankton dan zooplankton serta melihat penciri stasiun berdasarkan plankton dan kualitas perairan. Sampel diambil pada Juni 2025 di 15 stasiun dengan plankton net berukuran 30 µm. Ditemukan 47 genus fitoplankton dan 30 genus zooplankton. Kelimpahan fitoplankton berkisar 5.151,57–63.760,72 sel/m³, didominasi Trichodesmium sp., sedangkan zooplankton berkisar 139,87–1.971,07 ind/m³, didominasi Crustacea. Indeks keanekaragaman fitoplankton (H' = 0,19–1,85) rendah–sedang akibat dominansi Trichodesmium sp., sementara zooplankton (H' = 0,76–1,90) tergolong rendah hingga sedang dengan sebaran individu yang relatif lebih merata. Analisis similaritas menunjukkan adanya pengelompokan komunitas antarstasiun, PCA menunjukkan penciri beberapa stasiun berdasarkan plankton dan kualitas perairan. Secara umum, kondisi perairan KKP3K KDPS masih mendukung kehidupan plankton dan biota laut lainnya.; The Coastal and Small Islands Conservation Area (KKP3K) of the Derawan Islands and Surrounding Waters (KDPS) has high biodiversity, but there is less scientific information about the biodiversity of plankton there This study aimed to determine the composition, abundance, and biodiversity indices of phytoplankton and zooplankton, as well as their relationship with water quality. Samples were collected in June 2025 at 15 stations using a 30 µm plankton net. The results showed that there were 47 genera of phytoplankton and 30 genera of zooplankton. The phytoplankton abundance varied from 5151,57–63760,72 cells/m3 and was dominated by Trichodesmium sp., while the zooplankton abundance varied from 139,87–1971,07 ind/m3 and was dominated by Crustacea. The phytoplankton diversity index varied from 0,19 to 1,85 (low to moderate) and was also dominated by Trichodesmium sp., while the zooplankton diversity index varied from 0,76 to 1,90 (low to moderate). Similarity analysis showed that phytoplankton and zooplankton samples formed groups, while PCA showed that there were several stations that had similar characteristics based on plankton data and water quality data. In general, it can be said that water quality in the KKP3K KDPS was suitable for supporting plankton and other aquatic organisms.

2026-01-01T00:00:00Z