I Gusti Ngurah Putra Dirgayusa’s research while affiliated with Udayana University and other places

Microplastic contamination in table salt has emerged as a significant environmental and public health concern, particularly in regions like Bali, Indonesia, where salt is predominantly produced through seawater crystallization This study aimed to quantify and characterize microplastics in local and non-local table salts and estimate the potential microplastic intake. A total of 20 salt brands (10 local, 10 non-local) were collected and analyzed using density separation, stereomicroscopy, and FTIR spectroscopy. The results indicated that all salt samples contained microplastics, with an average concentration of 173 ± 119 particles/kg. Non-local salts exhibited higher contamination levels (211 ± 134 particles/kg) compared to local salts (135 ± 88 particles/kg). Fragments were the most prevalent microplastic type (55%), followed by fibers (44%), and smaller particles (≤500 μm) were the most common in size. A total of 13 polymer types were identified in the microplastic samples, with chlorobutyl (33%) and ethylene propylene rubber (29%) being the most dominant. Based on salt consumption rates, it was estimated that Bali residents ingest 1 microplastic particles per day, translating to an annual intake of 316–425 particles. These findings highlight the widespread nature of microplastic contamination in consumable salt and suggest potential health risks from the ingestion of microplastics, which may carry harmful pollutants. The study emphasizes the need for improved salt production practices, stricter pollution controls, and further research into the health implications of microplastic ingestion.

Tuna longline fishing was first introduced tothe Indonesian people around 1954, pioneered by theCenter for Marine Fisheries, and for the first time in1962, long line tuna fishing was attemptedcommercially by BPU Fisheries. Fisheries.Longlinetuna fisheries in Indonesia, especially in the IndianOcean, began to develop since the establishment of thestate company PT (Persero) Fisheries Samudra Besarin 1972 which is located in Benoa, Bali. Benoa Harboris the main port in Bali Province and is one of thebases for the distribution of tuna fish in Indonesiaapart from Muara Baru (Jakarta), Pelabuhan Ratu(West Java) and Cilacap (Central Java). As one of themain tuna fishing ports, Benoa Harbor is the base forindustrial scale tuna fishing vessels operating in thewaters of the Indian Ocean.

The Tourism Suitability Index (IKW) shows the assessment of an area regarding the level of suitability/feasibility to become a tourist attraction. An important aspect in the use of natural resources for tourism activities is the suitability of tourism and strategies for its development. The research aims to determine the value of the Tourism Suitability Index (IKW) and development strategies that can be used for management at Mengening Beach, Badung Regency, Bali. Data collection was carried out in April-May 2024 at three observation stations. Data collection uses primary and secondary data. Primary data is based on observations of beach type parameters, beach width, depth, beach slope, current speed, water brightness, bottom water material, land cover, availability of clean water, dangerous biota as well as questionnaire interviews with beach visitors using purposive sampling techniques. Data analysis uses the results of IKW measurements and SWOT analysis. Based on IKW calculations at three points, namely station I of 2,195, station II of 2,475, and station III of 2,475. The total analysis value of 2.0 ≤ IKW < 2.5 is included in the appropriate category. The strategy that can be applied at Mengening Beach in developing beach tourism is the SO (Strength-Opportunity) strategy, which involves external management at Mengening Beach, optimizing the use of social media and adding tourist attractions at Mengening Beach.

The tourism suitability index (TSI) is criteria of resources and the environment to meet the needs of tourism development. The tourism suitability index research was carried out at Batu Bolong Beach, Canggu with the aim of knowing tourism suitability index and tourism area utilization zone for beach recreation activities. Method used field observation by purposive sampling at 4 station points which are divided into a beach length of 640 m. Data retrieval in the form of 10 parameters: water depth, beach type, water current velocity, coastal slope, water base material, beach width, water brightness, dangerous biota, fresh water availability, and coastal land cover. Tourism suitability analysis based on TSI matrix with considering classification of four types categories. The limiting factors at Batu Bolong Beach are the brightness of the waters and the closure of coastal land. The value of tourism suitability for tourism activities in the beach recreation category based on assessment of stations I, II, III, and IV are different, namely 98.80%, 94.04%, 95.23%, and 91.67%. So this indicates that each station in the coastal area can be declared very suitable category for recreational tourism activities. The zones for use of coastal tourism areas include sports, walks, sunbathing, swimming, and surfing. The sunbathing, walking, swimming, and surfing zones can be done at all stations, while the sports zone can be done at stations I and IV. The sacred zone is located in the northern area, stations I and III which are adjacent to station II.

Ecotourism is one of the special tours where these activities pay attention to the environment and strongly support responsible tourism. Ecotourism is an environmental services in mangrove area of Bengkak Village, Wongsorejo District, are one of the unexploited natural resource potentials. The research aim to examine Mangrove ecosystem’s potential as an ecotourism destination and to establish a development strategy for Mangrove Center Bengkak. This research took place in the Mangrove Center Bengkak, Wongsorejo District, Banyuangi Regency, between February and April 2020. The descriptive exploratory survey method enable in this research, which included both primary data and secondary data. The interview method us in the research a list of questions (questionnaire) aimed at tourists, surrounding communities and managements. The data obtained were analyzed land suitability, area carrying capacity, implementation of the concepts of ecotourism and SWOT analysis. The result of the suitability analysis show that the Mangrove Center Bengkak, with a Tourism Suitability Index of 67 percent, is suitable to be used as an ecotourism area. Tourism activities in the Mangrove Center Bengkak area also have carrying capacity of 167 people per day. Mangrove Center Bengkak has implemented the principle of ecotourism. However, the application of these principles has not yet implemented properly. Its needs a lot improvement. The conclusion of this study is Mangrove Center Bengkak area has the potential for ecotourism development.

Marine ecotourism is one way of developing tourism in coastal areas that pays attention to ecology and maintains environmental stability. This study was conducted to determine the value of the Tourism Suitability Index (IKW) at Pemuteran Beach, Grokgak, Buleleng by considering 10 parameters such as water depth, beach type, beach width, water base material, water current velocity, beach slope, water brightness, coastal land cover, hazardous biota, and freshwater availability. The method of determining the location using the purposive sampling method is by taking an intentional and determined sample so that what you want to study can be represented by the number of stations, as many as 4 station points. The IKW analysis in this study refers to the suitability classification of coastal tourism and the tourism suitability matrix. Based on the results of the IKW analysis at Pemuteran Beach, each station, namely Station I has a value of 77%, station II is 79%, station III is 83%, and Station IV is 82%. It has the type and basic material of the beach with a black sand substrate with a mixture of coral fragments with a depth of 1.55-1.7 m; including shallow waters, the average width of the beach is quite wide, which is 11.5 m. In addition to this, Pemuteran Beach has a coastal slope of less than 10o with an average current speed of 0.27 m/s and has 100% water clarity. Coastal land cover is generally in the form of resident settlements.

Klungkung Regency is the smallest regency in the province of Bali, Indonesia. The waters of Jumpai Beach are one of the areas in Klungkung, which is one area that is used by the surrounding population for fishing activities for fishermen to obtain fishery products. Remote sensing technology has been applied because of its effectiveness and the significance of its use in compiling and revising resource maps. It is also helpful to support resource planning and management. A bathymetry map is a map that describes the depth of the sea and is presented using contour lines. Contour lines are abstract lines connecting several locations or areas with the same height or depth. Remote sensing techniques are available to determine the ocean’s depth because the air has signals from the very bottom of the ocean with strong solid wavelengths. However, the penetration of electromagnetic energy is limited. Therefore, remote sensing techniques are adopted to infer water depth and shallowness. One of the satellites that can be used for bathymetry mapping is Landsat-8. Landsat imagery has a spatial resolution of 30 meters, complemented by the visible channels required to extract bathymetric maps. Accurate estimation of shallow water area bathymetry for the safety of small boat navigation such as fishing and for benthic studies. Remote sensing technology can be considered one of the most desirable alternative tools for bathymetry development.

Keberadaan komunitas ikan karang menjadi dapat menjadi cerminan dari kondisi kesehatan ekosistem terumbu karang. Demografi terumbukarang cenderung berbeda terhadap kondisi tempat hidupnya dimana salah satunya dipengaruhi oleh kedalaman perairan, yang dapat berimplikasi terhadap perbedaan komunitas ikan karang yang berasosiasi. Penelitian ini memiliki tujuan untuk menentukan perbedaan komunitas ikan karang yang dilihat berdasarkan nilai kelimpahan, indeks struktur komunitas (keanekaragaman, keseragaman dan dominansi), serta biomassanya yang disandingkan dengan kondisi lingkungan perairan. Metode pengamatan visual sensus digunakan dalam pengamatan ikan karang pada 8 stasiun, dengan luas area pengamatan 350 m2 per stasiun. Hasil pengamatan menunjukkan jumlah spesies ikan karang sebanyak 45 spesies, dengan tiga keluarga dominan: Pomacentridae, Achanturidae dan Chaetodonidae. Terdapat satu spesies ikan karang yang sangat jarang ditemukan Chrysiptera tricincta. Nilai indeks struktur komunitas juga tidak berbeda jauh antar stasiun pengamatan dan masih tergolong baik. Biomassa ikan karang memiliki interval nilai yang cukup berbeda dengan kisaran nilai 87-446 kg/ha. Banyaknya ikan dari keluarga acanthuridae yang ditemukan menjadi kontributor utama terhadap tingginya nilai biomassa ikan karang. Kondisi perairan masih mendukung kehidupan dari komunitas ikan karang. Hasil riset memberikan gambaran terkait kondisi komunitas ikan karang, sehingga dapat dijadikan pedoman dalam pengelolaan sumberdaya perikanan, khususnya pada ekosistem terkait.

Yeh Gangga Beach is growing tourist attraction in Tabanan Regency, Bali. Tourism activities have a close bond with natural resources owned by the tourist area. The feasibility/suitability of a tourist area and the number of visitors that can be accommodated in tourist activities is important to know, so as not to cause disruption to both tourist activities and the environment and the direction of development. This research has a purpose, namely knowing the Tourism Conformity Index and Regional Support Capacity for coastal recreation activities. The method used is purposive field observation sampling at 4 point stations and interviewing tourists by accidental random sampling. The data used is primary and secondary data, with analysis of The Tourism Conformity Index and Regional Carrying Capacity. The results of the study obtained an average area for tourism activities of 17.98 m2 and time for tourism activities for 2 hours 14 minutes per day with a value of Regional Support Capacity of 3,273 people/day, 98,190 people/month and 1,178,280 people/year. The Tourist Conformity Index shows a value of 85.11% at station 1, 86.90% at station 2, 77.97% at station 3, and 80.35% at station 4. With this area Yeh Gangga Beach is still under carrying capacity and still suitable for beach recreation activities in accordance with the utilization zone of beach recreation tourism in Yeh Gangga.

Mangrove ecosystems are ecosystems located in coastal areas that are affected by tides and have many functions, namely ecological, physiological and economic functions. The purpose of this study was to determine the health condition of the mangrove ecosystem and the diversity of mangrove species in the West Bali National Park area. The technique applied in this study was a purposive random sampling method, with a total of 65 plots, and to determine the health condition of the mangrove ecosystem using the Hemispherical photography method. The mangrove species found at the observation site were Avicennia offinalis, Aegiceras floridum, Bruguiera cylindrica, Ceriops tagal, Lumnitzera racemose, Rhizophora apiculata, Rhizophora mucronata, Sonneratia alba, and Sonneratia caseolaris. The value of mangrove health conditions is determined from several parameters such as canopy cover which has a range of cover values ranging from 51.35% - 66.67% with an average percentage cover of all data collection stations of 60.27%, density has a value range of 2100 trees/ha – 8867 trees/ha, with a diversity value of 0.97 in the low diversity category, and with an average environmental parameter value such as temperature around 28.1 ± 0.56?, while the average value of salinity is 22.3 ±3.27‰, and the average pH was 5.9±0.12, with sandy mud substrate dominating the entire observation area.