Mangrove ecosystems consist of tropical plants that have adapted to the salinity, tidal fluctuations, and loose soil condition. Identification of mangrove ecosystems can be carried out by direct survey methods or by utilizing remote sensing technology. This study aims to map the area, percent cover, and density of mangroves in Makassar City using Sentinel 2A Imagery. The method used is the NDVI transformation, followed by Unsupervised-ISODATA classification, ground check with the 10 x 10-meter plotting method, and hemispherical photography. The results showed that the existence of mangroves in Makassar City was still found in the Tallo and Biringkanaya districts, with 68.81 ha of mangrove ecosystem cover area in the range of 84.36 - 91.89% (dense category). Likewise, the vegetation index based on NDVI analysis ranged from 0.73 - 0.81 (dense category), and the species density was in the range of 2700 - 6400 trees/Ha (dense category). Sentinel-2A imagery transformed with NDVI can be used to track mangrove areas and their density. The wide distribution of mangrove ecosystems in Makassar is relatively small but has good conditions.

Marine plastic debris, particularly microplastics (MPs), is an urgent and significant threat to the global marine environment. The emergence of MPs in the marine environment and their potential presence in human-consumed seafood necessitates immediate investigation. In light of this, a study was conducted on the occurrence of MPs in shellfish collected from two locations in Makassar Strait with distinct oceanographic conditions. Three commonly consumed shellfish species (Perna viridis, Meretrix meretrix, and Mactra chinensis) were collected by fishermen and examined for microplastic contamination, with a total sample size of 170 individuals. Microplastics were extracted from the soft tissue of the bivalves using the alkaline digestion method. The results revealed a significantly higher number of microplastics ingested by P. viridis and M. chinensis in samples collected from the Sanrobengi Islands (14.64 MPs/individual and 2.29 MPs/individual, respectively), compared to the P. viridis and M. meretrix from Mandalle coastal area (0.70 MPs/individual and 1.00 MPs/individual, respectively). The predominant microplastic form detected was blue microfibres. A prevalence of MP contamination between 58 and 100% and the results of Fourier Transform Infrared Spectroscopy (FTIR) analysis indicated that polystyrene was the dominant polymer present, threatening the welfare of the bivalve mollusks and posing potential health risks to seafood consumers. The results emphasize the urgent need for pollution control measures such as reducing plastic waste discharges and improving waste management systems. In addition, a comprehensive study focusing on the long-term ecological and health effects of microplastic pollution is necessary to guide future policy interventions.

Mangrove merupakan salah satu ekosistem pesisir yang sangat penting karena memiliki fungsi ekologis serta ekonomis bagi masyarakat pesisir. Saat ini hutan mangrove mengalami kerusakan dari tekanan yang berat akibat pertumbuhan penduduk. Untuk mengurangi kerusakan mangrove maka perlu dilakukan upaya rehabilitasi mangrove. Penelitian ini bertujuan menganalisis dan memetakan kesesuaian lahan untuk mengrove di Kecamatan Bontoa. Manfaat dari penelitian yaitu memberikan informasi tentang analisis kesesuaian lahan untuk rehabilitasi mangrove. Penelitian ini dilaksanakan pada bulan Maret 2011. Metode yang digunakan adalah metode survey lapangan dengan parameter kondisi arus, pasang surut, gelombang, suhu, salinitas, kondisi substrat dan kemiringan lereng. Data dianalisis dengan metode skoring dan diplot berdasarkan peta. Hasil penelitian menunjukkan dua kategori kesesuaian yaitu sesuai dan cukup sesuai. Untuk jenis sesuai didapatkan jenis Rhizophora spp, Avicennia spp, Sonneratia alba , S. caseolaris , Bruguiera parvilofa dan B. Xesangula . Sementara kategori cukup sesuai dari jenis B. gymnorhiza . Kondisi mangrove yang dapat direhabilitasi di Desa Ampelkale sebesar 55,375 ha, Desa Pajukuang 6,636 ha, dan Desa Bontobahari 16,011 ha.Kata kunci : kesesuaian lahan dan rehabilitasi ekosistem mangrove

Research on mapping and monitoring of seagrass ecosystems using satellite imagery data is still lacking. The availability of spatial information on benthic habitat is becoming very important with the increasing awareness of environmentally based management. Various methods of analysing remote sensing information on benthic habitat have been developed and utilized, such as the application of the Lyzenga algorithm. This algorithm requires data on the variation of water depth in the coastal areas to be mapped. The purpose of this research was to study the effect of using Lyzenga algorithm on the mapping of coral reef / seagrass ecosystem by comparing the results of seabed classification from Sentinel-2a imagery processed and without using the Lyzenga algorithm. Image classification with Lyzenga algorithm is easily recognizable with the Lyzenga index value format that has been freed from the effect of water depth. In this study, benthic cover in the shallow waters around Bontosua Island, Spermonde Archipelago-Indonesia, was classified using six habitat types: aquatic, land, sand, rubble, coral and seagrass. Seagrass habitat was further classified based on percentage cover as class 4 (76-100%), class 3 (51-75%), class 2 (26-50%) and class 1 (0-25%). Based on the analysis of Sentinel-2a data, the area with seagrass cover was estimated at 31.27 Ha. Seagrass mapping using medium-resolution satellite imagery can be helpful in providing data over a more extensive area than is likely to be possible using direct observation in the field alone.

Global warming has a great effect on the climate changes and the hydro-oceanography activities in the ocean, has caused threats of the extreme wave disasters and the coastal abrasion along the coastal areas. This research aims to investigate the level of extreme wave threats and the comparative descriptive analysis method. To look at the causality correlation between the study parameter and the interpretation parameter which is used to conclude the disaster level of threat of the extreme wave and the coastal abrasion. The data analysis uses the software of QGIS 2.8.11, and the analysis table is taken from the regulation of chief of the National Disaster Management Agency number 2 of 2012, which has been modified by the author based on the local conditions of the research location. The research results indicate that the coastal areas of Makassar city have threats of the extreme waves and the coastal abrasion with the total threat value ranging from 1,30-3,00. The threat of extreme wave disaster and the category of the abrasion were high in the coastal area of Tamalate, which has the total threat values of to 3,00, while the threat categories in the sub-districts of Wajo, Ujung Tanah, and Tallo were medium ranging from 1,70 to 2,20. The lowest categories were found in the sub-districts of Biringkanaya, Tamalanrea, and Mariso of which the threats range from 1,3 to 1,6. Decreasing the disaster risk can be done through several strategies, including developing a disaster management plan, establishing a program of decreasing disaster risk, creating an early disaster warning system, and disseminating the program of decreasing disaster risk to the coastal community.