Since the mass production of plastic in 1940, contamination of marine environment by plastics particularly micro plastics has been a growing problem. Micro plastics are little plastic particles, fibers and granules which have been defined in different sizes such as diameter less than 10, 5, 2 and 1 mm. The micro plastics that are made in microscopic size and are used in cleaner and cosmetic materials, are called primary micro plastics and secondary micro plastics are derived from larger particles. Micro plastics are directly transmitted to rivers and then sea via wastewater influent or leachates from refuse sites. Micro plastics are found throughout the water column and due to their small size, micro plastics are considered bioavailable for organisms. Their composition and relatively large surface area make them prone for adhering waterborne organic pollutants such as PAHs, PCBs and DDT. Micro plastics consumption by marine organisms have been shown by environmental and laboratory studies. Although adverse health effects via micro plastics are not obvious alone, but the transition of chemical materials from microplastics to organisms throughout the food-chain is a significant concern. In this article, micro plastics properties, micro plastics production resources, their entering effects on environment have been considered.

BACKGROUND AND OBJECTIVES: Conservation efforts are often prioritized on a large spatial scale because information about local ecosystems is frequently lacking. Therefore, comprehensive spatial classification of a region’, s environmental characteristics is essential for effective marine conservation. This study aimed to construct geophysical and chemical environmental delineation of the Lesser Sunda Islands which are located in Indonesia. This area is an ecoregion in the coral triangle that has been a primary concern of global biodiversity conservation strategies. METHODS: This study utilized eleven global environmental variables that were accessed from global marine databases. After performing a principal component analysis, a fuzzy C-means clustering technique was used to classify the region into groups based on environmental characteristics in term of seasonal variability. It was expected that the areas within each group would have identical attributes and ecological processes. FINDINGS: The results suggested that the marine environmental factors in Lesser Sunda can be simplified using a principal component analysis technique: 6 principal component factors explained 81. 06 percent of the overall raw data variability for the wet season, and 7 principal component variables explained 84. 51 percent of the overall raw data variability for the dry season. Then, the area can be delineated into 5 groups (wet season) and 10 groups (dry season) with different environmental characteristics. This method’, s classified groups principally inferred the Indian Ocean and Bali Sea, Savu Sea and Flores Sea, and Banda Sea as distinct clusters. In particular, the group that included the Indian Ocean had characteristics including lower nitrate and sea surface temperature concentrations, as well as higher potential hydrogen salinity and distance from the shore. CONCLUSION: The findings of this study showed that the single marine conservation area in Lesser Sunda is not sufficient to adequately represent the physicochemical dynamics in the area. The proposed delineation result will supplement the existing bioregion classification of marine areas, such as the Marine Ecoregions of the World. Moreover, it is also consistent with existing conservation programs, including the notable national marine protected areas of the Savu Sea. Nevertheless, the acknowledged biogeographic group of the Indian Ocean indicates that countries must work together to successfully manage marine protected areas and achieve their conservation objectives. This work serves as a baseline for both academic research and ecological assessment, and it will contribute to marine protected areas strategies and conservation efforts in the Lesser Sunda Islands.

BACKGROUND AND OBJECTIVES: Enggano Island is in the Indonesian Sea, bordering the Indian Ocean. Cross-border marine debris will be stranded in the coastal areas of this island. This study was carried out over a 12-month, from June 2021 to May 2022, to examine marine debris's spatial and temporal accumulation. The study aims to examine whether the level of marine debris accumulation on the coast of Enggano Island is very high (because it borders the Indian Ocean).METHODS: This study was conducted by using a survey method in the southeastern of Enggano Island with 10 stations. The first sampling was carried out 30 days after cleaning, during the lowest tide at the full moon phase (28 ± 3 days), conducted over 12 months from June 2021 to May 2022 to represent four seasons. The abundance data for each marine debris category was calculated both by the number of items and weight. Seasonal abundance analysis was compared with the average seasonal current speed to determine whether currents affect the abundance of marine debris.FINDINGS: The total marine debris collected in this study was 16,382 items with a cumulative weight of 24,826 grams. The average marine debris abundance was 0.387 ± 0.006 items per square meters, and the average weight was 11.545 ± 0.146 grams per square meters. Plastic has the highest percentage of all square meter’s categories in all locations and seasons, namely 91.55 percent to 92.54 percent. The dominant types of debris in all macro-debris categories are Styrofoam, plastic bottles, plastic rope or small net pieces, thin plastic wrap, and Plastic cups. The Marine debris found during the cleaning was plastic bottles from China, Switzerland, Sri Lanka, India, the Maldives, Myanmar, Malaysia, Singapore, Thailand, the Philippines, Australia, Seychelles, and the Middle East, with an average percentage of Indonesian-brand bottles (58.12 percent), foreign-brand bottles (19.59 percent), and unrecognized brands (22.29 percent). Moreover, there were significant differences in marine debris abundances and weights between sites and seasons during sampling. CONCLUSION: The marine debris that washed ashore on Enggano Island during the 12-month observation period, from June 2021 to May 2022, showed significant spatiotemporal variations. Variations in the accumulation of marine debris between stations, as well as the direction and velocity of the seasonal currents, influenced each season. Plastic is the category of marine debris with the highest percentage in all locations and seasons, specifically 91.55–92.54 percent. Global marine hydrodynamics is thought to play an important role in marine debris strandings, therefore more comprehensive research is needed to assess the influence of hydrodynamics in determining the source and height of marine debris strandings, especially those originating from outside Enggano Island.