Rasio Jumlah Mikroplastik dan Plankton di Kawasan Perairan Teluk Benoa, Bali

Plastic waste will degrade in the water and will break down into small particles called microplastics. Microplastics have a shape similar to food sources for marine organisms such as plankton, where if these microplastics are accidentally ingested by marine organisms it will enter the food chain and end up in humans through bioaccumulation and biomagnification. Plankton are divided into two types, namely phytoplankton as the main water producer and zooplankton as the second energy level that connects major producers with consumers at a higher level of food. This research was conducted to determine the type and ratio of the amount of microplastic and plankton as a source of food for marine organisms. This research was conducted in the waters of Benoa Bay, which is a semi-closed water area and has a variety of activities and there are also two large rivers that can contribute to pollution waste in the waters of Benoa Bay, this can lead to competition between the amount of plastic and plankton as the main producer in food chain. This research was conducted from February to July 2020 and sample analysis was carried out at the Marine Science Laboratory, Faculty of Marine and Fisheries Sciences, Udayana University. Sampling is done by pulling the trawl horizontally with a distance of 500 meters and a constant boat speed of 5 km/hour. The composition of the types of microplastics found were film, fragment, foam and fiber. The highest composition of phytoplankton comes from the Bacillariophyceae class, while the highest composition of zooplankton comes from the Malacostraca class. The average total abundance of microplastics is 1.69 particles/m3, while the average total abundance of plankton is 2851 Ind/m3 and a ratio of 1:1687. This result shows that until now the abundance of plankton is still much greater than the abundance of microplastics in the waters. However, considering the high amount of plastic use from household and tourism activities, it can also increase the inclusion of plastic waste that will enter the ocean.

Studi Karakteristik Suhu Permukaan Laut (SPL) Di Perairan Selat Lombok Menggunakan Citra Satelit EOS Aqua MODIS

The Lombok Strait is a strait located between Lombok Island and Bali Island which connects the waters of the Bali Sea to the Indian Ocean, whose SST conditions vary with oceanographic-atmospheric conditions in the Indian Ocean and the Pacific Ocean. This research aims to determine the temporal and spatial SST in the North and South Lombok Strait. Therefore, this study divides the Lombok Strait area into two because of the influence of the Pacific Ocean and the Indian Ocean. The method used in this research is descriptive and statistical analysis. The highest average monthly SST in the northern and southern Lombok Strait occurred in April at 29.11 °C and the lowest in August at 26.82°C. For the average seasonal SST, the highest occurred at transition I of 28.86°C, and the lowest occurred in the eastern season at 27.39°C. The highest average annual SST occurred in 2010 at 28.83°C and the lowest occurred in 2018 at 27.69°C. The northern SST anomaly has the same fluctuation as ENSO with inversely proportional IOD. Southern SST anomaly has fluctuation which is inversely proportional to ENSO and IOD. The correlation between SST anomaly in the north and ENSO correlates 0.90 (very strong), while with IOD it correlates 0.12 (very low). The correlation between SST anomaly in the southern part and ENSO correlates -0.11 (very low), while with IOD it correlates -0.73 (strong)

Strategi Pengurangan Sampah Plastik di Laut Pada Kawasan Konservasi Perairan Nusa Penida : Studi Kasus Pulau Nusa Lembongan

Coastal and marine areas on small islands have a higher vulnerability to the impact of plastic waste, where plastic is a material that is difficult to decompose. Nusa Lembongan Island is one of the small islands that is included in the Marine Protected Area (MPA) and is one of the world's marine tourism destinations with various tourism activities in it. Tourism activities have a large enough opportunity for plastic waste pollution in the environment. This study aims to develop a priority strategy for reducing plastic waste based on the approach of internal and external factors on the island of Nusa Lembongan using the analysis of Strengths, Weaknesses, Opportunities, Threats (SWOT), and Analytical Hierarchy Process (AHP). Data were collected by observation, literature study, interviews, and questionnaires. Respondents were determined by purposive sampling and snowball sampling. The results of the data obtained were analyzed using the SWOT method which resulted in alternative strategies which were then analyzed using the AHP method. The results of the study indicate that the priority strategy is to maximize environmental facilities and add segregated waste bins to create mutually beneficial relationships with groups of self-management services and to realize the prevention of the use of single-use plastic waste as stated in Pergub Bali no. 97 of 2018 take advantage of the support of local NGOs to carry out synergistic and sustainable socialization.

Tutupan Terumbu Karang pada Kedalaman Berbeda di Perairan Pantai Batu Sungu, Desa Les, Kabupaten Buleleng

Bali island has many magnificent underwater coral reef gardens that attract tourists. Besides Pemuteran and Menjangan island waters, Batu Sungu water has also potential to be a new tourist destination. Thus, to determine the potency and management plan in Batu Sungu waters, this research aimed to examine the overall coral cover, coral growth forms, other benthic forms, and each of their components in 5 and 10 m depths. The overall coral cover, coral growth forms, other benthic forms, and each of their components were counted by using the Line Intercept Transect (LIT) method. Before collecting data, study sites were observed by using the Manta Tow method. Data were collected in 2 depths (5 dan 10 m) with 5 sites each (replicates) that separates within 50 to 150 m. A 25 m LIT was spread parallel to the coastline above the reefs. Live coral colonies, other benthic forms below the transects were measured for the number, length, and growth forms. Water quality was measured in situ (temperature, current, and clarity) and ex situ (pH). Results showed that the category of coral coverage in Batu Sungu water is "good” in 5 m and "moderate” in 10 m whereas there was no significant difference among each component of the overall coral cover. The most dominant coral growth form among the 2 depths was Coral Massive whereas significantly abundant in 5 m. Moreover, the number of Coral Foliose was found significantly high in the same depth. Other coral growth forms were relatively similar in numbers in two depths. As likewise, the cover of other benthic forms and its component were not significantly different among two depths, except Dead Coral with Algae which significantly plentiful in 5 m. Sand was dominantly found in two depths with no significant difference. Furthermore, Coraline Alga was only observed in 5 m, however, there were no Macroalga and Alga Assemblages found at this depth. It is assumed that the similarity number of the overall coral cover, coral growth forms, other benthic forms, and each of their components is related to the alikeness of water quality among the two depths.

Pengaruh Suhu Permukaan Laut (SPL) terhadap Curah Hujan di Perairan Bali menggunakan Data Citra Satelit

Rainfall is a weather element. Sea surface temperatures (SST) affects precipitation. SST and rainfall have a high variability which can be measured by satellite. At a regional scale, a research of the effect of SST on rainfall analyzed island rainfall, which means that there is still little research on rainfall in the waters. This study purposed to find out the variability and correlation between SST and rainfall in the Bali waters. It used satellite MODIS and TRMM for 10 years, started from 2010 to 2019. The data used was SST MODIS and rainfall TRMM level 3 with the geographic coordinates boundaries area 114.4281o East - 115.7145o East, and 7.8168o South 8.9868o South. The method of this study was correlation analyzed with time lag between of SST and rainfall. The variability of SST in the Bali waters were ranged from 25,2 oC to 31,6 oC. Furthermore, the variability of rainfall was ranged from 0 mm to 556,92 mm. The changes patterns of SST and precipitation in Bali water were related to the season in each month. The data showed that the SST was warmer in the rainy season compared to the SST in the dry season. Besides, the rainfall increases when entering the rainy season, and the decreases when entering the dry season. The correlation between SST and rainfall in this waters area ranged from weak to strong. Correlation formed in the rainy season is negative with a correlation coefficient between -0.34 to -0.74. However, in the dry season there was a positive correlation with a correlation coefficient ranging from 0.77 to 0.92.

Analisis Filogenetik Ikan Tuna (Thunnus spp.) yang didaratkan di Pelabuhan Benoa, Bali

Tuna is one of the largest fisheries commodities in Indonesia after shrimp and demersal fish. The genus Thunnus is a type of tuna that dominates the international market. The genus Thunnus consisted of seven species of tuna. In some cases, the same morphological character has caused misidentification and data collection on tuna species. Therefore, this study aimed to identify tuna species that are landed at Benoa Harbor and analyzed their phylogenetic relationships. Species identification and phylogenetic analysed in this study used the mtDNA control region locus. The results of this study indicated that there are five tuna species landed at Benoa Harbor, namely yellowfin tuna (T. albacares), longtail tuna (T. tonggol), bigeye tuna (T. obesus), southern bluefin tuna (T. maccoyii), and albacore tuna (T. alalunga). Based on phylogenetic tree reconstruction, all samples were divided into five according to the number of tuna species resulted from molecular identification. Reconstruction of phylogenetic trees is supported by genetic distance between clades has a value of 0.075 - 0.212, with the closest kinship found in yellowfin tuna (T. albacares) with bigeye tuna (T. obesus) and the farthest found in yelowfin tuna (T. albacares) with albacore tuna (T. alalunga).

Deteksi Perubahan Garis Pantai Menggunakan Teknik Geospasial, Studi Kasus Kecamatan Tejakula

The coastal area in Tejakula Subdistrict has many potential benefits for local people and the development of the region. Regarding its economic perspective, marine biodiversity can be utilized for tourism development. In terms of culture and history, this area has many archaeological findings ranging from prehistory until the colonial period. However, the recent study from Balai Arkeologi Bali stated the objects were sunk into underwater at a depth of 1-2 meters due to the abrasion process. Therefore, this research discussed the changes of shoreline in the Tejakula Subdistrict area as a preliminary study to protect and preserve its potential values. This research, both in terms of economy, culture, and history. The calculation of shoreline changes is using the Digital Shoreline Analysis System (DSAS) application with Net Shoreline Movement (NSM) and End Point Rate (EPR) methods. The results showed that the coastal segment in Tejakula District experienced an abrasion change with an abrasion rate of 0.89 m/year based on the SPOT satellite image analysis and 0.17 m/year from Landsat satellite imagery.

Pengaruh Perbedaan Ukuran Jaring Insang Terhadap Hasil Tangkapan Ikan Tongkol Euthynnus sp. di Perairan Tenggara Kabupaten Karangasem

Tuna is one of the main catching commodities in the waters of Southeast Karangasem. Fishers in the Southeast waters of Karangasem used drift gillnet operations to find pelagic fish such as mackerel. This study aims to determine the composition of fish catches using different net sizes and determine the effect of different gill nets on the catch of tuna fish in the southeast waters of the Karangasem Regency. The study was conducted for one month from mid-October to mid-November 2017 by following fishers' fishing trips. The fishing gear used was gill nets with differences, namely 2' 2.5 and 3 inches. The data was taken directly by operating the gill net, which has three different mesh sizes then the data was analyzed by ANOVA. Based on the research found four types of fish, namely Tuna (Euthynnus sp.), ikan kembung (Restrelliger kanagurta), barracuda (Sphyraena barracuda), and Manta sp. with details on 2.5 sized nets, three species (cobs, mackerel, barracuda), while sediment nets with a size of 2 (tuna and mackerel), and 3 (tuna and manta rays). Each gets two types of fish. Based on the ANOVA test, the calculated F results in this study are (7.7608) and F table (3.4668). The difference in the size of the gill nets significantly affects the catch of tongkol fish. The F test value shows that the F count was greater than the F table.

Karakteristik dan Sebaran Sampah Terdampar di Kawasan Pesisir Taman Nasional Bali Barat

The existence of marine debris can be a threat to marine ecosystems. Several studies have shown that marine debris can cause death of marine organisms and a degradation of ecosystems. The West Bali National Park (TNBB) is a conservation area in Bali that is also susceptible to be affected by marine debris pollution, due to its high population and anthropogenic activity in the area. Bali generates about 4.281 tons of waste per day, where 11% of it ends up in the ocean. Therefore, research about marine debris in TNBB is important. The purpose of this research is to find out the characteristics and distribution of stranded marine debris in the TNBB coastal area. This research was conducted in February 2020 at 23 stations by the shoreline. Marine debris data collection was carried out by adapting the method developed by the Commonwealth Scientific and Industrial Research Organization (CSIRO) Global Plastic Pollution Project. Marine debris exists along the coastline with the concentration range between 0.05 – 28.47 items/m2 with the average of 4.29 items/m2. As much as 92.3% of waste were plastic, dominated by three major debris classes, including soft plastic (44.8%), foam (30.8%), and hard plastic (12.4%). Marine debris in the area has various sizes and shapes. As much as 57.9% of debris at TNBB were whole items and the rest of it were fragment items. Marine debris size at TNBB tend to have a big relative size, i.e. between 8-16 cm (32%). Generally, marine debris at TNBB were mostly daily consumer items. Therefore, public awareness play an important role to decrease the amount of marine debris on the TNBB coastal area.

Analisis Pola Sebaran Area Upwelling di Selatan Indonesia Menggunakan Citra Modis Level 2

This research aimed to find out the pattern of spasio-temporal upwelling and its relation with El Nino Southern Oscillation (ENSO) in the southern waters of Java to the East Nusa Tenggara. Two indicators namely sea surface temperature (SST) and chlorofil-a data obtained from oceancolor database were used as an indicator of upwelling occurences. The overlay technique and correlation analyses were used to describe the relationship between upwelling and ENSO. The results showed the phenomenon of upwelling occurred along southern Java and East Nusa Tenggara. The appearance of upwelling occurred in the South Easth Monsoon until transition season which began in June and ended in November. The pattern of upwelling area for 17 years varies each season, where for the South Easth Monsoon in June it gained 6986 km2, in July 78294 km2, and in August 254212 km2. As for transition season II in September 166767 km2, in October 72033 km2, and November 1949 km2. The results also showed that upwelling intensity was influenced by ENSO indicated by correlation values that matched the correlation value between SST - ENSO was -0.78 and chlorophyll-a-ENSO was 0.98.