Batu Bilis Island Kelarik Village is surrounded by shallow coral reefs with a fairly bright level of water brightness, making it a habitat for important economic biota in the form of clam shells (Tridacnidae). The purpose of this study is to identify the types of clam shells and determine the value of shellfish. Closing data is carried out on 9 (nine) points. Using the Benthos Belt Transect method, with an observation area of 140 m². The results were found 2 (two) types of clams, namely Hole Clams (Tridacna crocea) and Small Clams (Tridacna maxima). The highest density of Hole Clams is at point 9 (nine) with a value of 1.142.9 individual/ha, then the lowest density at point 7 (seven) 142,86 individual/ha. The highest density of Small Clams is at point 7 (seven) with a density value of 928,57 individual/ha and the lowest density at point 8 (eight) with a value of 71,43 individual/ha. The quality of physical-chemical parameters in Batu Bilis waters is still in the normal range for the life of clams shells such as temperature 29,4⁰C, salinity 29,5‰, current speed 0,08 m/s and brightness 100%.

This study aims to determine the type and density of gastropods, the density of seagrass, seagrass closure. It also knows the association gastropods in seagrass ecosystem in the waters of the Senggarang Besar. The research was conducted by random sampling method using a point 31 transect squares measuring 1x1 meters for observation gastropods and seagrass. Results of the study were found 12 species of gastropods. Gastropod density values range between 0.35-2.94 individual/m². Results of research on the type of seagrass found 4 species of seagrass that is, Enhalus acoroides, Thalassia hemprichii, Halodule uninervis and Syringodium isoetifolium. A density value of seagrass species Enhalus acoides 14.32 individual/m², Thalassia hemprichii 86.39 individual/m², Halodule uninervis 21.58 individual/m² and Syringodium isoetifolium 3.87 individual/m². Total density of all seagrass 126.16 individual/m². The closure of the Seagrass Enhalus acoides 12,63%, Thalassia hemprichii 50,96%, Halodule unnerves 13,40%  and Syringodium isotifolium 0.29%. Total closure of all seagrass is 77,29%. The level of association between species of gastropods as many as 11 species have negative associations of which is Leavistrombus turturela, Strombus urceus, Planaxis sulcatus, Cerithium nesioticum, Cerithium Aluco, Cerithium zonatum, Pugilina cocholidium, Cronia margariticola, Muricodrupa fiscela, Pyrene epamella, Otopleura auriscati. While 1 species has a positive association level is kind of Rhinoclavis aspera.

Vaname shrimp is one of the fishery products that are expected to produce foreign exchange for the country besides tiger shrimp.  One factor that can affect the growth and the production of vaname shrimp culture is dense stocking. The research was conducted in October-December 2016 at the Balai Benih Ikan Pantai (BBIP) Ghonebalano, aims to determine the effect of different stocking density on the growth and survival of vaname shrimp.  The research was using Completely Randomized Design with three treatment levels of density, i.e. treatment A = 10 individuals per container, treatment B = 15 individuals per container and treatment C = 20 individuals per container and three replications.  The results showed that the highest growth was obtained in treatment A which was 1,563 g/individuals, compared with treatment B (1.189 g/individuals) and C treatment (0.834 g/individuals).  Survival rate in treatment A is 80.00%, B treatment equal to 75,56% and treatment C equal to 70,00%.  Analysis of variance at 95% confidence level (α0.05) showed that the different density had a significant effect on growth, but had no significant effect on survival rate of the vaname shrimp larvae.

Levels of density, production and decomposition of litter in Dompak Estuary Waters. The aim of this research is to determine the level of density, production and decomposition of Mangrove litter in the Dompak Estuary Waters of Tanjungpinang City. This research was carried out in February - March 2024. In determining the sampling points the researchers used the Purposive Sampling method. Sampling in this research used the line transect method. The results of the research show that the level of mangrove density at station 1 is 1,299 ind/ha in the medium category, station 2 is 599 ind/ha in the rare category and station 3 is 1,666 ind/ha in the dense category. Mangrove cover at station 1. Amounted to 73.83% with medium criteria in the medium category. Station 2. Amounting to 65.60% with medium criteria in the medium category and station 3 amounting to 79.93 with solid criteria in the good category and the production of mangrove litter in Dompak Estuary Waters is 3.09 gbk/m2. With a leaf composition of 7.10 gbk/m2, twigs of 0.48 gbk/m2 and flowers/leaves of 1.69 gbk/m2. Mangrove decomposition at station 1 was 21.74%, station 2 was 29.88% and station 3 was 21.14%.

The study aims to determine the optimum temperature, optimum density and optimum temperature and density interactions in milkfish (Chanos chanos) transportation. This research was conducted in 2016, in Kendari City, Southeast Sulawesi Province. This study uses a factorial design, consisting of Temperature and Density Factors. The design of the combination treatment of Temperature (A) namely Temperature 15 oC, A2 Temperature 18 oC, A3 Temperature 21 oC. For Density Factor (B), B1 Density of 600 individuals / container, B2 Density of 800 individuals / container, B3 Density of 1,000 individuals / container. The results of analysis of variance at 95% and 99% confidence level, the treatment in this study had no significant effect, where the F count is smaller than the F table. This shows that the combination of temperature and density tested in this study can be used for energy transportation activities for 14 hours. Based on the percentage of graduation of nener life tested in the transportation, starting from the biggest graduation to the smallest life pass, is a combination of 15 oC temperature treatment and a density of 1000 individuals 95.57%, a combination of 18 oC temperature treatment and a density of 800 individuals 95.04 %, a combination of temperature treatment of 21 oC and density of 1000 individuals 91.70%, combination of temperature treatment of 15 oC and density of 800 individuals 90.04%, combination of temperature treatment of 15 oC and density of 600 individuals 89.89%, combination of temperature treatment of 21 oC and a density of 800 individuals 88.67%, a combination of temperature treatment 18 oC and a density of 1000 individuals 88.07%, a combination of temperature treatment 21 oC and a density of 600 individuals 84.33% and a combination of temperature treatment 18 oC and density of 600 individuals 73.28%.

The study aimed to determine the growth and survival of Litopenaeus vannamei shrimp with the application of probiotics to different stocking densities.  The study was conducted from May to June 2018 at the Balai Benih Ikan Pantai (BBIP) Ghonebalano, Duruka District, Muna Regency, using a Completely Randomized Design (CRD) with three levels of solid stocking treatment namely treatment A is 18 individu per container, treatment B is 24  individu per container and treatment C is 30  individu per container with three replications.  Data analysis using Variance Analysis (ANOVA) at the confidence level of 95% (α 0.05).  The results showed that the highest daily growth was obtained at 24 individual densities of 5.88% per day, compared to 18 individual densities of 5.86% per day and 30 individual densities of 5.74% per day.  The highest absolute growth is obtained at 24 individual density of 2.43 g per individu, then 18 individual density of 2.15 g per individual, and the lowest at 30 individual density of 2.02 g per individual.  Survival at a density of 18 individual and a density of 24 individual at 88.89%, while a 30-ind density of 86.67%.  Analysis of variance (α 0.05) showed that the application of probiotics to different stocking densities had no significant effect on the daily growth rate of vannamei shrimp (p<0.939), absolute growth of vannamei shrimp (p<0.080), and survival of vannamei shrimp (p<0.744).

Mangroves are coastal ecosystems that have many benefits, including the ecological benefits of being a source of nutrients for marine life (aquatic biota) and a source of food for land biota. This study aimed to determine the species composition and community structure of mangrove vegetation based on the substrate type and the relationship between mangrove density and substrate texture in Borimasunggu Village, Labakang District. This research was carried out from July to August 2021 in the Borimasunggu Village, Labakkang District, Pangkep Regency. The research method is purposive random sampling which is divided into 3 stages. At each station, 3 transects/plots are determined. The study results found 3 mangrove species in Borimasunggu Village, Labakang District, based on the type of substrate, namely Rhizophora stylosa, Avicennia alba, and Sonneratia alba species. Relative Frequency (RFi) in Borimasunggu Sub-District, Labakang District, was found for all species equally, namely 33.33, the highest relative cover (RCi) was the species Rhizophora stylosa, which was 39.25, and the lowest Relative Coverage (RCi) was the mangrove species Sonneratia alba, which was 26,15. While the highest Significance Value (INP) is the mangrove species Rhizophora stylosa, which equals 148.66%, and the lowest Important Value (INP) is the mangrove species Sonneratia alba, which is equal to 70.59%. The highest relative density (RDi) was found in the mangrove species Rhizophora stylosa, which was 74.07% with a clay substrate type, followed by Avicennia alba 14.81% and Sonneratia alba 11.11% with a dusty clay substrate types.

Microplastic contamination in the aquatic environment poses a serious threat to the survival of the ecosystem because it is persistent. This study aims to analyze the concentration of microplastics in the water column in the coastal waters of South Larompong. Sampling was carried out using the volume reduce method with the neuston net at four stations, namely Bonepute Beach, Ponnori Beach, Babana Beach and Damaci Beach. The results showed that there was microplastic contamination and found as many as 386 microplastic particles with an average concentration of 2.68 particles/m³. The results of the analysis of microplastic concentrations showed significant differences (P<0.05) between stations. The highest concentrations of microplastics are found on Bonepute Beach which is an area of aquaculture, fishing and densely populated settlements, then followed by Ponnori Beach which is a tourist area. Meanwhile, the lowest microplastic concentrations are found on Babana Beach, which is the estuary area of the Temboe River and Damaci Beach which is a nearby area. Several forms of microplastics were found, namely granules, fibers, films and fragments which were the most dominant forms. Several colors of microplastics were found, namely blue, brown, green, red, white, and black which were the most dominant colors. There are two types of polymer found, namely HDPE (High Density Polyethylene) and PVA (Polyvinyl alcohol). The conclusion of this study is that the coastal waters of South Larompong have been contaminated with microplastics so that more attention is needed regarding the handling of plastic waste, especially microplastics.