Diagenetic Screening in Porites Fossil Corals from South Pagai, Kendari, and Banten Bay, Indonesia

Fossil corals are commonly used in paleoclimate studies to get records of climate parameters throughout the Holocene and beyond. Diagenesis is known as an important error source in paleoclimate reconstruction. The aim of this research was to provide a comprehensive diagenetic investigation involving 2D-XRD, petrographic analysis, and scanning electron microscopy (SEM) of Porites spp fossil samples from South Pagai, Kendari and Banten Bay, Indonesia as a starting point for further climate studies using coral proxies. This research focused on samples with around 1% calcite content, a level that can create misinterpretation of geochemical proxies. The results indicate that the samples from Banten Bay and South Pagai are well preserved and reliable for paleoclimate study. Only Sample BG1 is not recommended for further use in geochemical proxy analysis due to intensive diagenesis. 2D-XRD allows calcite screening without destroying the coral sample and assists in defining alternative sampling transects. Secondary aragonite and dissolution cannot be identified with 2D-XRD, therefore diagenetic screening should be combined with petrographic and SEM analysis in any areas presumed to have diagenetic textures

Upaya Peningkatan Pengetahuan tentang Bahaya Merokok pada Siswa SDIT Permata Bunda Mranggen, Demak

Jumlah perokok laki-laki di Demak, usia 15-24 tahun sebesar 18,8%, 25-34 tahun sejumlah 33,3%, dan 35-44 tahun sebesar 26,77%. Perilaku merokok, tidak terjadi secara tiba-tiba, akan tetapi dimulai sejak anak-anak atau remaja. Berdasarkan observasi dan survei awal yang dilakukan peneliti di SDIT Permata Bunda dan lingkungan sekitar Desa Batursari Mranggen Demak, ada sebagian alumni yang berada di lingkungan keluarga atau teman perokok, mulai tertarik merokok. Perilaku merokok sering terjadi pada siswa laki laki dan terjadi saat berada di luar lingkungan sekolah. Oleh karena itu perlu dilakukan edukasi tentang bahaya merokok kepada siswa. Tujuan pengkajian ini adalah untuk mengetahui tingkat pengetahuan tentang bahaya merokok dan pengaruh penyuluhan bahaya merokok pada siswa SDIT Permata Bunda kelas V dan VI. Penyuluhan dilakukan menggunakan presentasi diselingi video animasi bahaya merokok. Penelitian ini bersifat analitik kuantitatif dengan desain cross sectional, menggunakan alat ukur kuesioner pre-post penyuluhan. Sampel diambil dengan metode total sampling berjumlah 146 responden. Analisis data menggunakan Mc Nemar Didapatkan perbedaan bermakna antara tingkat pengetahuan bahaya merokok di antara nilai pretest dan postest (p<0,05). Pentingnya edukasi merokok, untuk meningkatkan pengetahuan siswa tentang bahaya merokok.In Demak, the prevalence of male smokers varies among age groups, with rates of 18.8% for ages 15-24, 33.3% for ages 25-34, and 26.77% for ages 35-44. According to the 2021 GATS survey, two out of three adult men in the region are smokers. The adoption of smoking behavior typically initiates during childhood or adolescence. Initial observations and surveys conducted by researchers at Permata Bunda Elementary School, within the vicinity of Batursari Mranggen Demak Village, reveal that some alumni are smokers, and their family or friends are showing an increasing interest in smoking. Smoking tendencies are prevalent among male students, particularly outside the school environment, emphasizing the need for comprehensive education on the hazards of smoking.  This study aims to assess the level of knowledge regarding the dangers of smoking and the impact of counseling on SDIT Permata Bunda students in grades V and VI. Counseling sessions utilized presentations combined with animated videos addressing the dangers of smoking. The research follows a quantitative analytical approach with a cross-sectional design, employing a pre-post counseling questionnaire for measurement. A total sampling method was used, encompassing 146 respondents. Data analysis was conducted using the Mc Nemar statistical test. Significant differences were observed between the pretest and posttest scores concerning the knowledge of the dangers of smoking (p<0.05). The study underscores the significance of smoking education in augmenting students' knowledge about the hazards associated with smoking. This emphasizes the need for ongoing efforts to educate students and mitigate the allure of smoking, especially among younger age groups

Geomorfologi Terumbu Karang dan Habitat Bentik Gugusan Pulau Biawak, Indramayu: Integrasi Studi Citra Satelit dan Sedimen Permukaan

Terletak di kawasan perairan Laut Jawa, Gugusan Pulau Biawak saat ini diprioritaskan untuk wilayah konservasi keanekaragaman hayati laut. Deskripsi tentang zona geomorfologi dan habitat bentik terumbu karang serta distribusi sedimen permukaan adalah salah satu informasi penting untuk mendukung kebijakan konservasi, walaupun hal tersebut sering luput dari perhatian para peneliti dan pengambil kebijakan. Studi ini memberikan gambaran geomorfologi terumbu karang dan habitat bentik terkait serta karakteristik sedimen permukaan dari tiga pulau di gugusan Pulau Biawak, Indramayu beserta faktor pengendali dan sifat khususnya melalui studi integrasi citra satelit dan analisis sedimen permukaan. Zona rataan terumbu menunjukkan dominasi endapan pasir dan fragmen koral serta kalkareus alga kecuali di Pulau Biawak banyak ditumbuhi Halimeda. Koloni terumbu karang tumbuh sumbur di zona lereng terumbu pada sisi bagian barat pulau pada kedalaman hingga 5 m. Tekstur sedimen menunjukkan dominasi pasir kasar tanpa pola gradasi seiring dengan perubahan geomorfologi dan habitat bentik. Komposisi sedimen didominasi oleh komponen bioklastik, yang terdiri atas koral dan moluska sebagai dua komponen tertinggi

Reef Geomorphology and Associated Habitats of Karimunjawa Islands, Indonesia: A Spatial Approach to Improve Coastal and Small Islands Management

The Karimunjawa Islands are situated in the offshore of Jepara region of Central Java with abundant coastal and marine resources including coral reefs. The reef geomorphology appears typical of fringing reefs worldwide comprising reef flat, reef crest and reef slope. The reef geomorphic profiles are generally gently sloping seaward with slightly raised reef crest along the reef edge. The reefs slope moderately (15-30°) at the upper forereef slope (~5-10 m depth) and tend to drop steeply, sometimes almost vertical, at depths of 10-30 m. The coral communities are found from the intertidal to a depth of about 15 m, with the most vigorous development occurring between 1.5 to 5 m. The reef flats have low coral cover and are extensively covered by a mixture of seagrass beds and carbonate sand. The reef crests, which mark boundaries between reef flat and upper forereef slope, are mainly colonized by mixed Acropora corals, mainly A. Hyacinthus. The forereef slopes have substantial coral growth prevailing mixed branching Acropora, Porites cylindrica and Porites sp. Sediments on the reef flats are mainly bioclastic materials derived from reef-erosion, including coral fragments, mollusks, foraminifera, red algae, Halimeda, Echinodermata, aggregate, quartz, and lithic fragments. Seagrass beds, mainly Enhalus, occur on the inner reef flat and are gradually shifted to macroalgae, predominantly Sargassum. The study provides a basic requirement for fisheries management and environmental monitoring for a mid-Sunda Shelf within a biodiversity “hotspot”

Legal Uncertainty In Fiduciary Guarantee Law: An Analysis Of Reality And Its Impact On Creditors

The existence of Law Number 42 of 1999 concerning Fiduciary Guarantees arises due to the urgency of the public who experience anxiety about collateral objects. This regulation addresses all fiduciary guarantees, but there is confusion and legal uncertainty in their implementation in the community. This can be seen from the concept and reality in the field that is not balanced. Therefore, the author will discuss this issue using normative legal research methods by taking a statutory and conceptual approach, as well as the formulation of the problem discussed, namely legal uncertainty in UUJF in juridical, normative, and sociological aspects to the impact on legal uncertainty, especially on creditors. This study aims to provide views and understanding of how such legal uncertainty occurs and its impact on the creditors concerned. The results of this study show that regulations regarding fiduciaries are still said to have not provided legal certainty for the Indonesian people, especially from creditors. Keywords: Fiduciary Guarantee, Creditor, Legal Certaint

Modern and sub-fossil corals suggest reduced temperature variability in the eastern pole of the Indian Ocean Dipole during the medieval climate anomaly

We present two 40 year records of monthly coral Sr/Ca ratios from the eastern pole of the Indian Ocean Dipole. A modern coral covers the period from 1968 to 2007. A sub-fossil coral derives from the medieval climate anomaly (MCA) and spans 1100–1140 ad. The modern coral records SST variability in the eastern pole of the Indian Ocean Dipole. A strong correlation is also found between coral Sr/Ca and the IOD index. The correlation with ENSO is asymmetric: the coral shows a moderate correlation with El Niño and a weak correlation with La Niña. The modern coral shows large interannual variability. Extreme IOD events cause cooling > 3 °C (1994, 1997) or ~ 2 °C (2006). In total, the modern coral indicates 32 warm/cool events, with 16 cool and 16 warm events. The MCA coral shows 24 warm/cool events, with 14 cool and 10 warm events. Only one cool event could be comparable to the positive Indian Ocean Dipole in 2006. The seasonal cycle of the MCA coral is reduced (< 50% of to the modern) and the skewness of the Sr/Ca data is lower. This suggests a deeper thermocline in the eastern Indian Ocean associated with a La Niña-like mean state in the Indo-Pacific during the MCA

Diagenetic Screening in Porites Fossil Corals from South Pagai, Kendari, and Banten Bay, Indonesia

Fossil corals are commonly used in paleoclimate studies to get records of climate parameters throughout the Holocene and beyond. Diagenesis is known as an important error source in paleoclimate reconstruction. The aim of this research was to provide a comprehensive diagenetic investigation involving 2D-XRD, petrographic analysis, and scanning electron microscopy (SEM) of Porites spp fossil samples from South Pagai, Kendari and Banten Bay, Indonesia as a starting point for further climate studies using coral proxies. This research focused on samples with around 1% calcite content, a level that can create misinterpretation of geochemical proxies. The results indicate that the samples from Banten Bay and South Pagai are well preserved and reliable for paleoclimate study. Only Sample BG1 is not recommended for further use in geochemical proxy analysis due to intensive diagenesis. 2D-XRD allows calcite screening without destroying the coral sample and assists in defining alternative sampling transects. Secondary aragonite and dissolution cannot be identified with 2D-XRD, therefore diagenetic screening should be combined with petrographic and SEM analysis in any areas presumed to have diagenetic textures

The mineralogic and isotopic fingerprint of equatorial carbonates: Kepulauan Seribu, Indonesia

Kepulauan Seribu is an isolated patch reef complex situated in the Java Sea (Indonesia) and is a typical example for a humid, equatorial carbonate system. We investigate the mineralogical and isotopic fingerprint of Panggang, one of the reef platforms of Kepulauan Seribu, to evaluate differences to other carbonate systems, using isotope in combination with XRD and SEM analysis. A characteristic property of shallow water (13C and δ18O values. This is related to the isotopically depleted riverine input. The δ13CDIC in riverine water is reduced by the contribution of 12C from riverside mangroves. Deep atmospheric convection and intensive rains contribute 18O-depleted freshwater in the river catchments, finally reducing salinity in the Java Sea. The depleted δ13C signature in carbonates is further enhanced by the lack of green algae and inorganic carbonates and abundance of coral debris. Low δ18O values in carbonates are favored by the high water temperatures in the equatorial setting. Since equatorial carbonates in SE Asia, including the Java Sea, are typically influenced by high turbidity and/or river runoff, the observed distinctively low isotope values likely are characteristic for equatorial carbonate systems in the region.Lembaga Pengelola Dana Pendidikan (ID)Christian-Albrechts-Universität zu Kiel (3094

Microplastics as a sedimentary component in reef systems: A case study from the Java Sea

Microplastic pollution has been reported from coral reef systems all over the tropics. Exposure to microplastics has several negative impacts on coral health, such as bleaching, tissue necrosis, or an impairment of the coral’s immune system. Despite this potential risk for reef systems, the controlling processes for microplastics dispersion and accumulation in reef sediments are still largely under‐studied. Presented here is a study of microplastics (125 µm to 5 mm) distribution in two tropic atoll reef platforms in Kepulauan Seribu, Indonesia. Sediment samples were collected in different facies zones within the reef platform. Microplastics were concentrated using density floatation and characterized by light and scanning electron microscopy. Some particles were identified as polypropylene using micro‐Fourier transform infrared spectroscopy. All recovered microplastics were classified as secondary microplastics, likely derived from marine and local sources, with fibres as the most abundant type. Microplastics are showing similar transport and accumulation behaviour as fine siliciclastic grains. The abundance of microplastic is controlled by the proximity to the source area of larger plastic debris and hydrodynamic processes. Microplastics are not only present in low energy environments but also high energy settings such as the reef crest. Processes that contribute to accumulation in reef sediments are biofouling, interlocking and the creation of compound grains. Microplastics are present in sediment close to the seafloor (0 to 3.5 cm) but also at depths between 3.5 cm and 7.0 cm. Microplastic particles from below 3.5 cm are unlikely to be remobilized under modal weather conditions in the studied equatorial reefs. Subtidal reef sediment therefore can be regarded as a permanent sink for microplastics. The study shows that microplastics in coral reef environments deserve careful consideration since microplastics pose an additional threat to corals and their ability as framework builders in reef systems