ANALYSIS ACTIVITY 14C OF CORAL REEF IN KAYANGAN ISLAND

The work is to determine absorption capacity, optimum time analysis, efficiency enumeration (TDCR), specific activityof 14C and coral age. Steps taken are physical and chemical washing, CO2 absorption, and analysis using liquid scintillation counter Hidex 300 SL. Due to washing, the weight loss was 4.74%. Total carbon absorbed was 1,056 grams. CO2 absorption capacity using KOH was 47% while optimum time analysis by LSC was 30 minutes and average efficiency enumeration (TDCR) was 0.6877.  It was concluded that specific activityof 14C was 14.7361 DPM/gC and coral age in Kayangan Island was 310.49 years

DINAMIKA TOTAL SUSPENDED SOLID DAN LAND COVER DI PERAIRAN PELABUHAN BIMA, TELUK BIMA, NUSA TENGGARA BARAT: (The Dynamics of Total Suspended Solid and Land Cover in the Port of Bima, Bima Bay, West Nusa Tenggara)

Kawasan Teluk Bima merupakan salah satu lokasi perairan strategis yang berada di Kabupaten Bima dan Kota Bima. Teluk ini memiliki manfaat multifungsi sesuai dengan peruntukan penduduk sekitar teluk yang didominasi Suku Bima. Di wilayah pesisirnya terutama dimanfaatkan untuk pelabuhan, tambak, lokasi wisata dan permukiman pantai. Teluk Bima termasuk kawasan laut semi tertutup mirip seperti bentuk kantong, dimana terdiri dari mulut teluk yang sempit kemudian badan air teluk yang melebar di bagian dalam.  Teluk ini merupakan tempat bermuaranya daerah aliran sungai (DAS) dan sub-DAS yang mengalirkan air dari semua pegunungan yang melingkupinya, diantaranya Sub-DAS Malaju dan Padolo. Adanya aktivitas pada Sub-DAS Malaju dan Padolo mengakibatkan terjadinya peningkatan sedimentasi di kolam pelabuhan. Penelitian dimaksudkan untuk melihat peningkatan total suspended solid (TSS) dan perubahan lahan pada DAS serta melihat korelasi antara perubahan tutupan lahan dengan meningkatnya persebaran sedimen tersuspensi tersebut. Penelitian ini menggunakan algoritma Parwati et al. (2006) untuk melihat sebaran TSS di Teluk Bima serta melakukan pengujian sampel untuk menghitung TSS di lapangan. Selanjutnya melakukan analisis korelasi dengan melihat hubungan perubahan TSS dengan perubahan tutupan lahan yang ada. Hasil penelitian ini menunjukkan terjadinya peningkatan TSS pada kawasan Teluk Bima. Tahun 1990, sebaran TSS >80 mg/l sebesar 0,45 ha dan pada tahun 2020 meningkat menjadi 35,89 ha. Pertanian lahan kering dan permukiman mengalami peningkatan masing-masing sebesar 9% dan 4%, sedangkan belukar berkurang 13%. Jenis tutupan lahan tertentu menjadi penyebab meningkatnya luas sebaran TSS, seperti pertanian lahan kering dengan nilai korelasi positif sebesar 1 dan permukiman dengan nilai korelasi positif sebesar 1

Combining environmental DNA and visual surveys can inform conservation planning for coral reefs

Environmental DNA (eDNA) metabarcoding has the potential to revolutionize conservation planning by providing spatially and taxonomically comprehensive data on biodiversity and ecosystem conditions, but its utility to inform the design of protected areas remains untested. Here, we quantify whether and how identifying conservation priority areas within coral reef ecosystems differs when biodiversity information is collected via eDNA analyses or traditional visual census records. We focus on 147 coral reefs in Indonesia’s hyper-diverse Wallacea region and show large discrepancies in the allocation and spatial design of conservation priority areas when coral reef species were surveyed with underwater visual techniques (fishes, corals, and algae) or eDNA metabarcoding (eukaryotes and metazoans). Specifically, incidental protection occurred for 55% of eDNA species when targets were set for species detected by visual surveys and 71% vice versa. This finding is supported by generally low overlap in detection between visual census and eDNA methods at species level, with more overlap at higher taxonomic ranks. Incomplete taxonomic reference databases for the highly diverse Wallacea reefs, and the complementary detection of species by the two methods, underscore the current need to combine different biodiversity data sources to maximize species representation in conservation planning

ANALISIS SPASIAL UNTUK UJI AKURASI DAN PENGEMBANGAN ALGORITMA PEMETAAN OBYEK DASAR PERAIRAN DANGKAL DENGAN MENGGUNAKAN CITRA ALOS AVNIR 2

ABSTRAK TEKNOSAINS 2010Identifikasi obyek dasar permukaan perairan dangkal (ODPD) memerlukan kajian dan pendekatan khusus. Terdapat beberapa metode yang dapat digunakan untuk mengidentifikasi ODPD secara lebih baik dan lebih akurat yakni metode klasifikasi dan metode algoritma. Penelitian ini difokuskan pada metode klasifikasi gambar citra satelit ALOS AVNIR II. Beberapa metode yang diuji adalah Attenuated Lyzenga Method (ALM), metode Re-Class dan Composit Citra yakni Box Classification (parallelepiped) dan metode Minimum Distance yang terbentuk terhadap rata-rata algoritma , serta metode Maximum Likelihood. Uji akurasi dan penentuan model yang terbaik menggunakan Uji Penanda dan Uji Kappa. Hasil penelitian menunjukkan metode Re-class dari ALM, dan composite Citra 312 dengan metode klasifikasi Minimum Distance serta Maximum Likelihood dapat digunakan untuk mengidentifikasi obyek dasar permukaan perairan dangkal. Tes akurasi menunjukkan bahwa Image Composit 312 dengan metode klasifikasi maximum likelihood merupakan model terbaik yang bisa digunakan untuk identifikasi obyek dasar permukaan peraira

THE ACCURACY TEST OF SEVERAL IMAGE'S CLASSIFICATION METHODS USING ALOS AVNIR II IMAGE

The identification of shallow-water surface objects needs special study for its identification processes. There are many methods that could be used for good identification in algorithm and classification model. This research was focused more in the classification method of the satellite images of ALOS AVNIR II. Method used was the Attenuated Lyzenga Method (ALM) with Re-class and image composite with Box Classification (parallelepiped), minimum distance to mean algorithm and maximum likelihood. The accuracy test and the determination of the model were best performed with the sign test and the kappa Test. Results of the previous research showed that Re-class from the ALM, and image composite 312 with classification method of minimum distance and maximum likelihood could be used for identification of the object of shallow-water surface; and the accuracy Test showed that image composite 312 with the classification method of maximum likelihood was the best model to be used in the identification of the shallow-water surface objects

ACUTE TOXICITY OF CADMIUM (Cd) TO VELIGER LARVAE OF FLUTED GIANT CLAM (Tridacna squamosa LAMARCK, 1819)

Clams have a planktonic period which is sensitive to metal pollutants in the waters. The natural concentration of cadmium (Cd) is relatively low in marine waters but may increase with increasing anthropogenic activity on land that may be lethal to organisms, especially in the sensitive larval stages. The purpose of this study was to analyze the values of 24h-LC50, NOEC (No Observed Effect Concentration), LOEC (Lowest Observed Effect Concentration) and MATC (Maximum Acceptable Toxicant Concentration) along with the impact of acute Cd toxicity on mortality and morphological changes of Tridacna squamosa veliger. The toxicity test used was an acute toxicity test with a static method (4 replications). Acute toxicity tests were performed on veliger phase larvae with short-term exposure (24 hours) on various Cd concentrations ie., 0.1 mg/L, 1 mg/L, 2.5 mg/L, 5 mg/L and 10 mg/L . The 24h-LC50 value was calculated using the Trimmed Spearman-Karber application version 4.1, and the LOEC and NOEC values were analyzed using the Dunnet test. Results showed that the 24h-LC50 value of Cd applied to Tridacna squamosa veliger was 2.12 mg/L, whereas the NOEC, LOEC, and MATC values were 1 mg/L, 2.5 mg/L, 1.581 mg/L respectively.  Mortalities were observed with increasing Cd concentrations. It was also shown a decreasing number of zooxanthellae, damaged in mantle tissue and shells, changes in shell color, released of mantle tissue from the shell with increasing Cd concentrations.</jats:p

Genetic patterns of the corals Euphyllia glabrescens and Lobophyllia corymbosa across the Indonesian Archipelago

Abstract. Jompa J, Umar W, Yusuf S, Tassakka ACM, Limmon GV, Rahmi, Putri AP, Halwi, Tamti H, Moore AM. 2020. Genetic patterns of the corals Euphyllia glabrescens and Lobophyllia corymbosa across the Indonesian Archipelago. Biodiversitas 21: xxxx. Scleractinian corals can reproduce in several ways, with two main sexual reproduction modes known as brooding and broadcast spawning. In this study, we described patterns of genetic variation within and connectivity between coral populations in western Indonesia (Seribu Archipelago), central Indonesia (Spermonde Archipelago), and eastern Indonesia (Ambon). We sampled two readily identifiable corals popular in the marine aquarium trade, one species widely reported as a brooder (Euphyllia glabrescens), the other as a broadcast spawner (Lobophyllia corymbosa). The mitochondrial COI genome was amplified for 117 samples. Within-population genetic variation was high, especially at the eastern Indonesia (Ambon) site. The genetic connectivity patterns were similar for the two corals, with high connectivity between the Seribu and Spermonde Archipelagos (despite a geographical separation of more than 1,000 km) and a lack of connectivity between these two sites and Ambon. These results indicate a potential barrier to gene flow between coral populations in western/central Indonesia and those to the east of Sulawesi Island.</jats:p