DESAIN LAMPU HIGH POWERED LIGHT EMMITING DIODE (HPL) UNTUK PENCAHAYAAN KARANG DAN IKAN PADA AKUARIUM DISPLAY

Suplai cahaya merupakan salah satu faktor penting dalam sistem akuarium display yang mengembangkan perpaduan biota laut beberapa jenis karang dan ikan. Minimalnya ketahanan hidup biota laut di dalamnya menjadi fokus latar belakang penelitian ini. Faktor krusial berupa kurangnya pengetahuan tentang kebutuhan cahaya yang diimplementasikan merupakan salah satu penyebabnya, sehingga dirumuskanlah tujuan penelitian yaitu membuat desain sistem pencahayaan bagi beberapa jenis karang dan ikan pada akuarium display. Metode yang diterapkan meliputi desain konseptual, eksplorasi, observasi, pengukuran, perhitungan, desain awal, dan desain rinci. Hasilnya berupa desain akuarium berdimensi 300 cm x 70 cm x 70 cm dengan kapasitas volume air laut 1.333,233 liter menggunakan lampu HPL sebanyak 564 unit yang dilengkapi LED driver (25-36 Watt, 160 Volt DC) sebanyak 24 unit dan terbagi dalam 12 blok. Setiap blok terdapat 47 lampu HPL (16 day light, 16 cool light, 15 warm white) yang dirangkai seri dan dikoneksikan dengan 2 unit LED driver. HPL disematkan pada heat sink aluminium sebagai pendingin. Sebagai duplikasi moon light, actinic blue ditempatkan sejauh 2 meter dari sisi luar akuarium. Kesimpulannya desain HPL untuk pencahayaan karang dan ikan pada akuarium display berhasil dibuat sesuai konsep kebutuhan intensitas, jenis, dan durasi pencahayaan terhadap dimensi akuarium dan jenis biota yang dipelihara

Ecological status of threatened mangroves

Mangrove ecosystem Segara Anakan Lagoon (SAL), is the largest mangrove ecosystem in Java that is occupied by various types of mangroves. Several studies have shown the deforestation of mangrove in SAL which caused the decrease of mangrove biodiversity and species density. This study aims to obtain updated information on the distribution and density of two mangrove species found in SAL that are listed in the IUCN, which are Ceriops decandra (Threatened) and Merope angulata (Least Concerned). This research was conducted with the stages of literature study and analysis of satellite imagery using Sentinel 2 and the NDVI equation to obtain the change of mangrove cover and density. The literature study found that C. decandra was mostly distributed in the eastern and central sites of the Lagoon, while M. angulata was distributed in the center site. According to the spatial analysis, the density of Ceriops decandra was found >0,5 while Merope angulata is distributed in the center site with a medium density categorized. The degradation of the mangrove ecosystem in 2023 was estimated to be 10.493,64 ha. The information provided in this study is expected to improve conservation and protection actions for the sustainability of the threatened mangroves species in SAL

Distribution of macro plastic debris in Muaragembong coastal bay during the east moonson and the east to west monsoon transition in 2020

Marine debris pollution can threaten the sustainability of natural resources in coastal regions ecosystem. Marine debris is worldwide issue now and Indonesia considered as a second biggest polluter of plastic to the world ocean. Massive efforts have been applied to tackle marine debris, both by the central government and provincial level, to manage these problems and minimize the impact on the coastal ecosystem. Various types of marine debris threaten the mangrove and seagrass ecosystem by covering its roots and leaves, slowing down its growth rate, and even killing them. The aim of this research is to identify the composition of marine debris in estuary waters and mangrove ecosystem. The research activity was conducted in Muaragembong, Bekasi Regency, which is considered part of Jakarta Bay as the source of the marine debris site. The result showed that the marine debris composition during the east monsoon (July) was dominated by plastic with 71%, while during the transition east-to-west monsoon (November) ranged from 59% and equally distributed surrounding estuary waters and mangrove ecosystem. Fifteen types of macro plastic were found in waters in July, larger than those found in November (13 types). The predominant type of macro plastic is Styrofoam, followed by crackle plastic, sachets, and straws, most of which are single-use plastics that are transported to the estuary and then trapped in the mangrove ecosystem