Abstract: This study aimed to determine the abundance, diversity, and periphyton dominance in the pond using Lapindo mud that cultivated catfish of different sizes. The method used was descriptive quantitative, describing the relationship between the pool using Lapindo mud and fish cultivation of different sizes on the growth of periphyton on the walls of the pond. In this research, there were three different treatments: treatment A (100% Lapindo mud), treatment B (75% Lapindo mud), and treatment C (50% Lapindo mud). There were also three groups of catfish sizes: 4 cm, 6 cm, and 8 cm. The simple linear regression test showed that the age of the fish did not affect the growth of periphyton, while different concentrations of Lapindo mud influenced the growth of periphyton. In all ponds, the Cultivation Diversity Index was still relatively low. The results of periphyton diversity research in the polluted waters of Lapindo mud indicated the dominance index value and the highest abundance of Bacillariophyceae. The most common types of Bacillariophyceae were Amphora and Diatoma. The abundance of the genus indicate that they are easy to adapt to contaminated water areas. Show less...

Abstract: Medan Belawan, especially Sicanang Village, is a coastal area suitable for ponds. To replace pond water, the existing water must be drained first, so it's important to assess the land's drainage capability when selecting pond locations. This study aims to predict drainage ability by measuring the drainage depth (D) in pond channels at five observation stations. Using field surveys and both primary and secondary data, the study compares the results with criteria for aquaculture ponds. The findings show that Stations I (D = 55 cm), II (D = 46 cm), IV (D = 51 cm), and V (D = 39 cm) fall under Class 2 (D 30-60 cm), indicating they can be used for ponds since they can drain water by gravity, though not completely dry. Station III (D = 26 cm), classified as Class 3 (D < 30 cm), is unsuitable for ponds due to poor drainage and is better used as conservation land. Show less...

Abstract: Bacteria are microscopic organisms, and a small portion of them are pathogenic or harmful to living organisms. One example is bacteria that cause damage and decay in captured Tuna fish (Thunnus sp.) off the coast of Kondang Merak, Malang. Therefore, to determine the genus of bacteria found in Tuna fish (Thunnus sp.), bacterial morphology identification was conducted. Bacterial morphology identification was performed using methods involving the identification of colony and cell morphology, as well as bacterial respiration tests to enhance genus prediction accuracy. Bacterial morphology identification involved several testing stages, including Gram-staining, cell observation and measurement, motility testing, and bacterial respiration testing. The bacterial isolation samples from Tuna fish (Thunnus sp.) on TSA media consisted of 8 samples, namely 1a, 1b, 2a, 2b, 3, 4a, 4b, and 5, which were differentiated based on bacterial colony morphology. Based on the results of colony morphology identification, cell morphology, and respiratory testing, all 8 bacterial samples were manually identified with reference to identification books. The identification results showed that several samples had similar morphological characteristics. The bacterial morphology identification results for samples 2a and 2b were identified as belonging to the genus Aeromonas; samples 4a and 4b were classified into the genus Mesophilobacter; sample 1a was categorized into the genus Carnobacterium; and samples 1b, 3, and 5 belonged to the genus Vibrio. Show less...

Abstract: Bacterial Resistance is defined as the inability of antibiotics to inhibit bacterial growth systemically, mainly caused by synthetic chemical antibiotics. Therefore, research on pharmacological alternatives to synthetic antibiotics with natural antibacterial agents is needed, one of which is the crude extract of mangrove snail (T. sulcata) tested against Escherichia coli (E. coli) bacteria. This study conducted phytochemical screening and antibacterial potential testing of T. sulcata meat extract. T. sulcata was extracted with a polar solution of Methanol pa 1:4. Antibacterial testing against E. coli was performed at different extract concentration levels (5,000 ppm - 20,000 ppm). The results showed antibacterial activity with the formation of inhibition zones in the E. coli bacterial suspension medium. ANOVA analysis indicated that the mangrove T. sulcate extract at various concentrations influenced the growth of E. coli bacteria. Differences in treatment demonstrated an increase in extract concentration, which was directly proportional to the diameter of the inhibition zone. Observations of changes in the inhibition zone indicated that T. sulcata extract exhibited bacteriostatic properties against E. coli, characterized by a reduction in the diameter of the inhibition zone at each treatment concentration level. The formation of inhibition zones is believed to be due to the activity of active compounds such as alkaloids, flavonoids, saponins, phenols, and terpenoids. Show less...

Abstract: Based on the Regional Spatial Plan (RTRW) of Surabaya for the period 2010-2030, Mulyorejo Subdistrict is designated as a mangrove preservation area that integrates ponds and marshes ecosystems. However, the limited available land and diverse societal conditions have led to economic development focused on natural resources, such as shrimp ponds. In order to ensure responsible and sustainable fisheries and marine utilization, this research aims to analyze the land suitability of L. vannamei ponds in the Mulyorejo Subdistrict using a Geographic Information System (GIS), considering water quality, land use, and geophysics. The methodology employed a land suitability matrix based on scoring and weighting data for each parameter, processed using ArcGIS 10.2 software. Spatial analysis was conducted by overlaying the spatial data of all parameters. Attribute analysis involved summing the scores of all parameters and classifying them into three categories: good (score 81-100), medium (score 63-80), and bad (score 45-62). The obtained data included pH levels ranging from 6.78 to 8.86, salinity levels of 0-25 ppt, nitrate levels of 0.05-0.26 ppt, phosphate levels of 0.04-1.71, soil C/N ratio ranging from 1 to 16, soil types identified as typic epiaquepts and typic endoaquepts, temperature at 28.8°C, evaporation rate of 2.84-4.50 mm/day, annual rainfall of 1,776-2,201 mm, and land use categories comprising settlements, ponds, mangrove forests, and vacant land. Based on the research findings, the land suitability for white shrimp ponds in Mulyorejo Subdistrict covers an area of 425.18 hectares, with the largest portion located in Kalisari Village. Show less...