Tropical marine environments are abundant and diverse; therefore, shark and ray research at fishing port PPS Lampulo, Banda Aceh City was carried out focusing on morphometric characteristics and differences based on multivariate analysis in July 2020 to identify sharks and rays that landed at fishing port PPS Lampulo, Banda Aceh City and determine their primary characteristics. The shark and ray samples used were from the Indian Ocean and the Malacca Strait and measured total length (TL), fork length (FL), and standard length (SL) for sharks and disc width (DW), TL, and disc length (DL) for rays. Principal component analysis (PCA) and discriminant analysis (DA) were performed on the morphometric data. The PCA analysis revealed that sharks and rays caught in Pelabuhan Perikanan Samudera (PPS) Lampulo, Banda Aceh City, can be divided into two distinct groups. The first group of sharks consists of species with large FL and SL morphometrics, namely P. kamoharai, C. plumbeus, P. glauca, and A. superciliosus. The second group of sharks consists of species with large TL morphometrics, specifically A. pelagicus and C. plumbeus. For the ray group, the first group comprises species with large TL and DW morphometrics, represented by A. ocellatus. The second group of rays consists of species with large DL morphometrics, namely P. sephen and H. jenkinsii. The results of DA revealed distinct differences in the size of sharks caught in the Indian Ocean and the Strait of Malacca, specifically in PPS Lampulo, Banda Aceh City. However, no significant differences in size were observed for the rays, regardless of whether their size was measured using DW, TL, or DL.

Seaweed is an important biological resource for human life, serving essential ecological functions, including providing shelter and feeding grounds for marine biota. Seaweed can be found in several Indonesian waters, growing naturally or through cultivation, including in the waters around Simeulue Island. This study aimed to assess the distribution of seaweed in relation to land suitability, using oceanographic parameters in Simeulue Island waters. The research was conducted at five stations within the West Teupah District, South Teupah District, and Alafan District. In situ measurements were taken to evaluate land suitability for seaweed growth based on oceanographic parameters such as current speed, depth, substrate type, salinity, temperature, pH, and dissolved oxygen. Results indicated that seaweed in Simeulue Island waters is distributed along the coastline and attached to coral reefs and rocks at depths of 2-5 meters. The total area of seaweed distribution is approximately 351.83 hectares along a coastline of 206.12 km. The measured parameters of seaweed habitats include a pH of 7.7 to 7.9, salinity of 31-35.3 ppt, temperature of 20-30 °C, dissolved oxygen levels of 3-4.8 mg/L, depth of 2-5 meters, current speed of 0.10 to 0.60 m/s, and a sandy coral substrate. Based on these water quality and substrate parameters, the seaweed habitats in Simeulue Island are classified as highly suitable, with suitability values ranging from 64 to 82. The recorded environmental conditions collectively support optimal seaweed growth.

Integrated Multitrophic Aquaculture System (IMTA) is a sustainable approach to aquaculture, utilizing ecosystem dynamics by integrating various species. This study examined the growth and survival of milkfish (Chanos chanos), tiger shrimp (Penaeus monodon), and oysters (Crassostrea spp.) in IMTA systems with different stocking densities. A 30-day experiment using a nonfactorial-completely randomized design with four treatments and three replications was conducted. The results showed that the implementation of IMTA had no significant impact on the survival rate of milkfish, tiger prawns or oysters in all treatments. However, important variations in growth parameters were observed. Milkfish and tiger prawns showed the highest weight and length gain in treatment B, followed by treatments A, C, and D. Similarly, oysters showed optimal growth in treatment B, followed by A, C, and D, based on weight gain, length, width, and shell thickness. Throughout the study, the physicochemical parameters of the water remained within acceptable ranges, thus supporting ideal growth conditions for the cultured species. These findings underscore the potential of IMTA to increase aquaculture productivity while upholding the principles of environmental sustainability. By optimizing stocking density and encouraging species diversity, IMTA presents a promising avenue for advancing integrated aquaculture practices, in line with the FAO's blue economy concept and ecosystem approach to aquaculture. Future research should concentrate on refining the IMTA system and evaluating its long-term ecological and economic consequences.

Water quality is one of several aspects that affect the success of aquaculture business. This study analyzes water quality and assesses its impact on aquaculture enterprises in the Rancong pond region of Lhokseumawe City. The study ran from November to December 2018. The water quality of the Rancong pond was sampled directly and tested in multiple labs. The field survey and purposive sampling strategy separated the research location into four stations with three water sampling points. Temperature, salinity, turbidity, brightness, pH, dissolved oxygen, alkalinity, total organic matter, BOD5, total ammonia nitrogen, nitrite, nitrate, phosphate, lead (Pb), total Vibrio bacteria, total general bacteria, and phytoplankton types and abundance were measured. The suitability of water quality is assessed using descriptive analysis, scoring, and matching. The investigation indicates that the quality and maintenance of the source water are highly suitable (S1). Traditional vannamei shrimp ponds in Rancong, Lhokseumawe City, should be maintained as fisheries cultivation areas.