Judul: Struktur Komunitas Ikan Terumbu Karang pada Kolom Air dan Sedimen di Perairan Lombok Berdasarkan Sampel DNA Lingkungan
Abstrak: Ikan terumbu karang merupakan organisme yang terkait penting untuk fungsi ekosistem. Ikan terumbu karang juga berfungsi sebagai sumber makanan utama dan bertindak sebagai indikator tekanan dan ketahanan ekosistem. Underwater Visual Census (UVC) adalah metode yang sering digunakan untuk memantau kekayaan dan kelimpahan ikan karang, yang mana pada kondisi ini masih kurangnya pencatatan yang tepat untuk nilai keanekaragaman karena kemampuan terbatas pada proses identifikasi dan pemantauan. DNA lingkungan (eDNA) adalah metode pembaruan untuk memperkirakan kekayaan dan kelimpahan komunitas ikan serta organisme lainnya yang masih sulit teridentifikasi dan terdeteksi dari kolom air dan sedimen. Oleh karena itu, penelitian ini dilakukan untuk mengkaji struktur komunitas ikan terumbu karang dengan membandingkan kolom air dan sedimen menggunakan metode metabarcoding DNA Lingkungan pada tiga daerah perlindungan laut yang berbeda di sekitar Lombok. Penelitian ini dilakukan pada bulan Agustus 2018 pada tiga kawasan perlindungan laut dengan 14 titik pengamatan secara total. Sampel DNA lingkungan diambil dari kolom air dan sedimen menggunakan botol sampel dengan volume 4 L, kemudian dipompa menggunakan alat peristaltik MASTERFLEX nomor 13-310-662 untuk disaring menggunakan kertas saring 0,4 μm. Metabarcoding DNA lingkungan merupakan metode yang digunakan untuk pengidentifikasian serta perhitungan komposisi maupun kelimpahan spesies ikan terumbu karang. Analisis data secara statistik berupa perhitungan indeks Shannon-Wiener (H’), Simpson (D), ANOSIM dan juga PERMANOVA untuk melihat signifikansi antar data analisis. Hasil penelitian menggambarkan struktur komunitas ikan terumbu karang pada komposisi, kekayaan, dan keragaman yang teridentifikasi dari penerapan metode DNA lingkungan. Sebanyak 58 spesies teridentifikasi dari semua kawasan perlindungan. Indeks Shannon-Wiener (H ') menunjukkan bahwa spesies Zona Inti memiliki nilai keanekaragaman yang lebih tinggi dibandingkan dengan dua zona lainnya. Indeks Simpson (D) menunjukkan semua zona memiliki nilai dominansi yang bervariasi. Sedangkan hasil analisis non-metric multidimensional scaling (NMDS) dengan uji Bray-Curtis didapatkan hasil yang berbeda nyata antara kolom air dan sedimen dengan hasil PERMANOVA Adonis Pr (> F) = 0,001 dengan nilai kurang dari 0,05. Hasil ini dapat menjadi acuan dalam penggunaan DNA lingkungan sebagai alternatif pemantauan hayati dan penilaian keanekaragaman karena pengambilan sampel DNA lingkungan memiliki banyak keuntungan karena pengambilan sampel tidak dipengaruhi oleh perubahan kondisi lapangan, visibilitas, atau kurangnya keahlian taksonomi., Coral reef fishes are diverse associated organisms that are essential for ecosystem functioning, carrying out a range of vital ecosystem services, while also serving as a primary source of food and acting as indicators of ecosystem stress and resilience. Underwater Visual Census (UVC) is an often method used in monitoring richness and abundance of reef fish above the coral reef substratum, which many cases the biodiversity is underestimated. The frontier method for estimating the richness and abundance of the fish community and other organisms is environmental DNA (eDNA) which can resolve rare taxa detected from mid-column water and sediment. Therefore, this study was conducted to assess the community structure of coral reef fishes by comparing the mid-column water and sediment of eDNA metabarcoding from three different marine protected reefs surrounding Lombok. This research was conducted in August 2018 in three marine protected areas with 14 sites in total. Environmental DNA sample was taken from mid-column water and sediments using a 4 L bottle, then pumped using peristaltic
Keyword: organic, preservation, integrated system, sustainable

Judul: Struktur Komunitas Invertebrata Laut di Kolom dan Sedimen  dengan Menggunakan Teknik Environmental DNA (eDNA) Metabarcoding  di Kawasan Terumbu Karang Raja Ampat
Abstrak: Invertebrate biodiversity monitoring activities carried out conventionally using direct fishing techniques and identification will be difficult, costly, time-consuming and can cause damage to the environment and communities. Previous studies related to biodiversity surveys of benthic invertebrate larvae have been carried out conventionally but it is difficult to identify them at the species level and only at the genus or family level. Environmental DNA (eDNA) is a molecular biology technique that has developed rapidly because this technique has been successfully applied as a survey method for new aquatic organisms in aquatic ecosystem research and biomonitoring programs and management on a large scale. This study aims to determine the structure community using the eDNA metabarcoding technique by comparing the water and sediment columns at the protected reefs of Raja Ampat, Indonesia. A total of 66 eDNA samples was collected from water and sediment columns. The sample extraction process was carried out using a protocol from the commercial Kit NucleoSpinTM Macherey-Nagel and followed by a PCR process using universal eukaryote primers targeting the 18S gene then sequencing using the Illumina Miseq technique. The order of the taxonomy is done using QIIME2 software and the SILVA database. This study succeeded in detecting 13 species of invertebrates in the water column and 9 species of sediment using NMDS statistical test with a distance matrix Bray-Curtis similarity and Andonis test showed , the number of sequence readings in the water column and sediment was not significantly different (p > 0.05). Shannon Wiener Index (H ') showed the low to moderate category (1 <H' <3), and not significant different revealed for the No-take zone, utility zone and open access zone the Kruskal-Wallis test, (p > 0.05). Simpson's (D) index ranges from 0.12 -1. SIMPER analysis on the water column of the species that has the highest percentage contribution, namely Strongylocentrotus purpuratus (34.05%) and Littorina littorea (54.21%)
Keyword: Biomonitoring, genetic conservation, Invertebrate, Raja Ampat

Judul: Approximation of the Median of Poisson Distribution Using the Relation of Poisson-Gamma Distribution
Abstrak: A major drawback of median is that median cannot usually be defined in closed form, even in the cases where their distribution functions are known. This study gives an approximation of the closed form for the median of the Poisson distribution by using the relation of Poisson-Gamma distribution. The approximation uses elementary techniques based on the monotonicity of certain sequences involving tail probabilities of the Poisson distribution and the Central Limit Theorem. Furthermore, a closed form expression for the mean absolute deviation 􀜧|􀜰􀰒 􀵆 􀜯􀝁􀝀􁈺􀜰􀰒􁈻| is also studied. The median is relevant because of the fact that it minimizes the mean absolute deviation of a Poisson random variable (􀜰􀰒􁈻 by considering median as central tendency.
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