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"Bentuk talus makroalga dan faktor lingkungan dapat memengaruhi kelimpahan dan keanekaragaman mikroalga epifitik. Sementara itu, penelitian tentang kelimpahan dan keanekaragaman mikroalga epifitik di Muara Binuangeun belum pernah dilakukan. Oleh sebab itu, dilakukan penelitian tentang kelimpahan dan keanekaragaman mikroalga epifitik pada makroalga, serta menganalisa pengaruh faktor lingkungan dan bentuk talus makroalga terhadap kelimpahan mikroalga epifitik pada makroalga di rataan terumbu Muara Binuangeun. Sampel mikroalga epifitik pada makroalga diambil dari 4 stasiun penelitian yang dipilih berdasarkan keberadaan makroalga. Hubungan mikroalga epifitik dengan bentuk talus makroalga diuji menggunakan uji Chi Square, sedangkan pengaruh parameter lingkungan dengan kelimpahan mikroalga epifitik diuji dengan uji korelasi Spearman. Kelimpahan mikroalga epifitik tertinggi terdapat makroalga berdaging dengan permukaan kasar, seperti Sargassum. Sementara itu, keanekaragaman mikroalga epifitik tertinggi terdapat pada Turbinaria. Mikroalga epifitik yang memiliki asosiasi dengan bentuk talus makroalga adalah Amphora. Amphora berasosiasi positif dengan bentuk talus berdaun. Parameter lingkungan yang cenderung berkorelasi kuat dengan kelimpahan mikroalga epifitik yaitu DO dan salinitas.

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Macroalgae form and environmental parameters may affect the abundance and diversity of epiphytic microalgae. Meanwhile, research on the abundance and diversity of epiphytic microalga in Muara Binuangeun has naver been done. Therefore, this research was conducted to determine abundance and diversity of epiphytic microalgae on macroalgae, and analized the effect of environment factor and macroalgae form to abundance of epiphytic microalgae on macroalgae in Muara Binuangeun reef flat. Samples of epiphytic microalgae were taken from 4 station which selected based on macroalgae presence. The relationship between epiphytic microalgae and macroalgae form was tested using Chi Square test, whereas effect of environmental parameter on the abundance of epiphytic microalgae tested using Spearman test. The highest abundance of epiphytic microalgae found in Sargassum and the highest diversity of epiphytic microalgae found in Turbinaria. Epiphytic microalgae that has associations with macroalgae form is Amphora. Amphora has positively associated with foliose macroalgae. Environmental parameters tend to be strongly correlated with abundance of epiphytic microalgae are DO and salinity."

"Dinoflagellata epifitik yang hidup pada lamun Thalassia hemprichii berpotensi menyebabkan Ciguatera Fish Poisoning (CFP) melalui produksi ciguatoxin atau asosiasi dengan dinoflagellata penghasilnya. Lamun Thalassia hemprichii memiliki kelimpahan tinggi di perairan Pulau Pramuka. Penelitian mengenai kelimpahan dinoflagellata epifitik pada lamun Thalassia hemprichii beserta hubungannya dengan parameter lingkungan dilakukan di empat sisi perairan Pulau Pramuka, Kepulauan Seribu. Sampel lamun Thalassia hemprichii dari keempat sisi pulau diambil secara purposive random sampling ke dalam botol, dikocok kuat selama beberapa menit, dan biofilm pada daun dikerik. Daun lamun dipisahkan dan diukur luas permukaannya. Sampel air hasil kocokan kemudian disaring menggunakan saringan bertingkat 125 dan 25 μm, dan diamati menggunakan mikroskop cahaya. Ditemukan empat genus dinoflagellata epifitik toksik, yaitu Coolia, Gambierdiscus, Ostreopsis, dan Prorocentrum. Genus Coolia memiliki rata-rata kelimpahan tertinggi, yaitu 8 sel/cm2, yang menunjukkan kemampuan adaptasi Coolia di setiap stasiun dengan faktor lingkungan yang berbeda. Faktor lingkungan yang mencirikan di tiap stasiun dianalisis menggunakan Analisis Komponen Utama (AKU) dan kemudian dihubungkan secara deskriptif dengan kelimpahan dinoflagellata. Bagian selatan dan barat pulau dicirikan oleh salinitas dan kecepatan arus, bagian utara oleh intensitas cahaya, dan bagian timur oleh nitrat, oksigen terlarut, dan pH.

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Epiphytic dinoflagellates living on Thalassia hemprichii seagrass have the potential to cause Ciguatera Fish Poisoning (CFP) through ciguatoxin production or association with dinoflagellate producers. Thalassia hemprichii seagrass has a high abundance in the waters of Pramuka Island. Research on the abundance of epiphytic dinoflagellates in seagrass Thalassia hemprichii and its relationship with environmental parameters was conducted on four sides of the waters of Pramuka Island, Kepulauan Seribu. Seagrass Thalassia hemprichii samples from the four sides of the island were taken by purposive random sampling into bottles, shaken vigorously for several minutes, and the biofilm on the leaves was scraped off. Seagrass leaves were separated and their surface area measured. The shaken water samples were then filtered using 125 and 25 μm graduated sieves, and observed using a light microscope. Four genera of toxic epiphytic dinoflagellates were found, namely Coolia, Gambierdiscus, Ostreopsis, and Prorocentrum. The genus Coolia had the highest average abundance, 8 cells/cm2, which indicates the adaptability of Coolia at each station with different environmental factors. Characteristic environmental factors at each station were analyzed using Principal Component Analysis (PCA) and then descriptively correlated with dinoflagellate abundance. The southern and western parts of the island were characterized by salinity and current velocity, the northern part by light intensity, and the eastern part by nitrate, dissolved oxygen, and pH."

"Dinoflagellata epifitik yang hidup pada lamun Thalassia hemprichii berpotensi menyebabkan Ciguatera Fish Poisoning (CFP) melalui produksi ciguatoxin atau asosiasi dengan dinoflagellata penghasilnya. Lamun Thalassia hemprichii memiliki kelimpahan tinggi di perairan Pulau Pramuka. Penelitian mengenai kelimpahan dinoflagellata epifitik pada lamun Thalassia hemprichii beserta hubungannya dengan parameter lingkungan dilakukan di empat sisi perairan Pulau Pramuka, Kepulauan Seribu. Sampel lamun Thalassia hemprichii dari keempat sisi pulau diambil secara purposive random sampling ke dalam botol, dikocok kuat selama beberapa menit, dan biofilm pada daun dikerik. Daun lamun dipisahkan dan diukur luas permukaannya. Sampel air hasil kocokan kemudian disaring menggunakan saringan bertingkat 125 dan 25 μm, dan diamati menggunakan mikroskop cahaya. Ditemukan empat genus dinoflagellata epifitik toksik, yaitu Coolia, Gambierdiscus, Ostreopsis, dan Prorocentrum. Genus Coolia memiliki rata-rata kelimpahan tertinggi, yaitu 8 sel/cm2, yang menunjukkan kemampuan adaptasi Coolia di setiap stasiun dengan faktor lingkungan yang berbeda. Faktor lingkungan yang mencirikan di tiap stasiun dianalisis menggunakan Analisis Komponen Utama (AKU) dan kemudian dihubungkan secara deskriptif dengan kelimpahan dinoflagellata. Bagian selatan dan barat pulau dicirikan oleh salinitas dan kecepatan arus, bagian utara oleh intensitas cahaya, dan bagian timur oleh nitrat, oksigen terlarut, dan pH.

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Epiphytic dinoflagellates living on Thalassia hemprichii seagrass have the potential to cause Ciguatera Fish Poisoning (CFP) through ciguatoxin production or association with dinoflagellate producers. Thalassia hemprichii seagrass has a high abundance in the waters of Pramuka Island. Research on the abundance of epiphytic dinoflagellates in seagrass Thalassia hemprichii and its relationship with environmental parameters was conducted on four sides of the waters of Pramuka Island, Kepulauan Seribu. Seagrass Thalassia hemprichii samples from the four sides of the island were taken by purposive random sampling into bottles, shaken vigorously for several minutes, and the biofilm on the leaves was scraped off. Seagrass leaves were separated and their surface area measured. The shaken water samples were then filtered using 125 and 25 μm graduated sieves, and observed using a light microscope. Four genera of toxic epiphytic dinoflagellates were found, namely Coolia, Gambierdiscus, Ostreopsis, and Prorocentrum. The genus Coolia had the highest average abundance, 8 cells/cm2, which indicates the adaptability of Coolia at each station with different environmental factors. Characteristic environmental factors at each station were analyzed using Principal Component Analysis (PCA) and then descriptively correlated with dinoflagellate abundance. The southern and western parts of the island were characterized by salinity and current velocity, the northern part by light intensity, and the eastern part by nitrate, dissolved oxygen, and pH."

"Telah dilakukan penelitian tentang Dinoflagellata Epifitik pada Lamun Enhalus acoroides di rataan terumbu Pulau Pari, Kepulauan Seribu pada Bulan April 2012. Penelitian dilakukan dengan mengoleksi daun lamun Enhalus acoroides dari rataan terumbu, kemudian dilakukan pengocokan dan penyaringan dengan saringan bertingkat (125µm dan 20µm). Dinoflagellata epifitik yang ditemukan berjumlah 8 jenis, yaitu Gambierdiscus toxicus, Ostreopsis lenticularis, O. ovata, O. siamensis, Prorocentrum concavum, P. emarginatum, P. lima, dan P. rhathymum. Enam dari jenis yang ditemukan merupakan Dinoflagellata epifitik yang berpotensi menyebabkan ciguatera. Kepadatan tertinggi Dinoflagellata epifitik terdapat pada stasiun 8 (577 sel/cm2) yang terletak pada bagian selatan pulau, sedangkan kepadatan terendah terdapat pada stasiun 1 (22 sel/cm2) yang terletak pada bagian barat pulau. Berdasarkan uji korelasi Spearman, parameter lingkungan perairan yang memengaruhi kepadatan Dinoflagellata epifitik saat penelitian adalah kecepatan arus dan oksigen terlarut (DO).

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Research on epiphytic Dinoflagellates on seagrass Enhalus acoroides had already conducted in Pari Island waters, Seribu Islands on April 2012. Research was carried out by collecting Enhalus acoroides leaves, which were shaken vigorously and the seawater filtered through a series of sieves (125µm and 20µm). Eight epiphytic Dinoflagellates were found, they were Gambierdiscus toxicus, Ostreopsis lenticularis, O. ovata, O. siamensis, Prorocentrum concavum, P. emarginatum, P. lima, and P. rhathymum. Six of the spesies found were epiphytic Dinoflagellates that potentially caused ciguatera. The highest density value of epiphytic Dinoflagellates was found at station 8 (577 sel/cm2) which located on the southern part of island and the lowest was at station 1 (22 sel/cm2) which located on the western part of island. Based on Spearman corellation test, the environmental factors which influenced the abundance of epiphytic Dinoflagellates at sampling time were current velocity and dissolved oxygen (DO)."

"Usaha mitigasi perubahan iklim dengan memanfaatkan vegetasi laut sebagaipenyerap blue carbon saat ini sedang digencarkan, salah satu vegetasi tersebut ialahmakroalga. Muara Binuangeun, Banten yang terletak di pesisir pulau Jawa merupakankawasan yang berpotensi sebagai penyerap CO2 dan dihuni oleh beragam jenismakroalga, antara lain Gracilaria verrucosa yang merupakan makroalga denganfrekuensi kehadiran tertinggi dan Halimeda opuntia yang dikenal sebagai makroalgaberkapur dimana kandungan nutriennya pernah diteliti di Muara Binuangeunsebelumnya. Penelitian ini telah dilakukan pada bulan Maret--Mei 2018, dengan tujuanuntuk mengetahui seberapa besar perbedaan potensi penyerapan dan penyimpanankarbon pada makroalga Gracilaria verrucosa dan Halimeda opuntia di MuaraBinuangeun, Banten. Hasil penelitian yang didapatkan yaitu rata-rata potensipenyerapan karbon G. verrucosa dan H. opuntia berturut-turut adalah sebesar 228,73gC/m2/hari dan 1500,57 gC/m2/hari, sedangkan rata-rata potensi penyimpanan karbonG. verrucosa dan H. opuntia berturut-turut adalah sebesar 135,29 gC/m2/hari dan217,01 gC/m2/hari. Kandungan karbon pada G. verrucosa adalah sebesar 4,47 sedangkan H. opuntia sebesar 4,64 . Berdasarkan analisis hasil uji T, potensipenyerapan karbon H. opuntia secara signifikan lebih tinggi dari G. verrucosa danpenyimpanan karbon H. opuntia lebih tinggi dari G. verrucosa namun tidak signifikan.Selain itu, kadar abu pada H. opuntia lebih tinggi daripada G. verrucosa dan kadar airH. opuntia lebih rendah daripada G. verrucosa. Hal tersebut dikarenakan H. opuntialebih banyak menyimpan karbon dalam bentuk zat kapur. Oleh karena itu, usahakonservasi dapat dilakukan pada makroalga yang berpotensi tinggi dalam penyerap danpenyimpan karbon seperti H. opuntia untuk mengurangi emisi karbon dari atmosfer.

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Efforts to mitigate climate change by utilizing marine vegetation as a blue carbonabsorber are currently being intensified, one of which is macroalgae vegetation. MuaraBinuangeun, Banten, which is located on the coast of Java, is a potential area as a CO2absorber and is inhabited by various types of macroalgae, including Gracilariaverrucosa which is the macroalgae with the highest attendance frequency and Halimedaopuntia, known as calcareous macroalgae, whose nutrient content have been studied inMuara Binuangeun before. This research was conducted in March May 2018, with theaim to know how much the difference of the carbon absorption and storage potentialbetween Gracilaria verrucosa and Halimeda opuntia in Muara Binuangeun, Banten.The result showed that the average carbon absorption potential of G. verrucosa and H.opuntia was 228.73 gC m2 day and 1500.57 gC m2 day, respectively, while the averagecarbon storage potential of G. verrucosa and H. opuntia were respectively 135.29gC m2 day and 217.01 gC m2 day. The carbon content of G. verrucosa was 4.47 whileH. opuntia was 4.64. Based on the analysis of T test results, the potential of H.opuntia carbon absorption was significantly higher than G. verrucosa and the carbonstorage of H. opuntia was higher than G. verrucosa but not significant. In addition, ashcontent in H. opuntia is higher than G. verrucosa while H. opuntia water content islower than G. verrucosa. It is because H. opuntia stores more carbon in the form ofcalcium carbonate. Therefore, conservation efforts can be done on high potential macroalgaein carbon sinks and storage such as H. opuntia to reduce carbon emissions fromthe atmosphere."

"Penelitian mengenai struktur komunitas lamun di perairan Muara Binuangeun, Banten, telah dilakukan pada tanggal 6--9 November 2015. Penelitian bertujuan untuk mengetahui struktur komunitas lamun yang mencakup persentase tutupan, frekuensi, kerapatan, indeks nilai kepentingan, indeks keanekaragaman, indeks kemerataan, dan indeks dominansi pada setiap stasiun di Muara Binuangeun. Penentuan lokasi pengambilan sampel dilakukan secara purposive sampling. Hasil penelitian menunjukkan bahwa jumlah jenis lamun yang diperoleh di Muara Binuangeun sebanyak 3 jenis dari 2 suku. Persentase tutupan lamun di setiap stasiun berkisar antara 28,40--61,60%. Kerapatan lamun di setiap stasiun berkisar antara 637--1655 individu/m2. Jenis Thalassia hemprichii memiliki frekuensi tertinggi berkisar 86,67--100%, sedangkan Halodule uninervis merupakan jenis dengan frekuensi terendah berkisar 6,67--20%. Thalassia hemprichii memiliki indeks nilai kepentingan tertinggi di Muara Binuangeun berkisar 138--300%, sedangkan Halodule uninervis memiliki indeks nilai kepentingan terendah yang berkisar antara 4--12%. Nilai indeks keanekaragaman di Muara Binuangeun tergolong rendah berkisar antara 0--0,73, dengan nilai indeks dominansi yang tergolong tinggi pada stasiun 1 dan 2 (1,00), tergolong sedang pada stasiun 3 (0,53) dan tergolong rendah pada stasiun 4 (0,49). Nilai indeks kemerataan pada stasiun 1 dan 2 yang tergolong rendah (0), serta stasiun 3 (0,63) dan 4 (0,67) yang tergolong tinggi. Secara umum, struktur komunitas lamun pada lokasi penelitian tergolong tidak stabil karena tingkat keanekaragaman dan kemerataan yang rendah serta tingkat dominansi yang tinggi.

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Research on community structure of seagrass in waters of Muara Binuangeun, Banten, was conducted on November 6th -- November 9th, 2015. The study aims to determine the community structure of seagrass which includes diversity, cover percentage, frequency, density, importance values, diversity index, evenness index, and dominance index at all of station in Muara Binuangeun. The location of sampling was determined by purposive sampling. The results showed that there are 3 species of seagrass from 2 family in Muara Binuangeun. Percentage seagrass covering in each station ranged from 28,40--61,60%. Seagrass density at each station ranged from 637--1655 individuals/m2. Thalassia hemprichii is the highest frequency (86,67--100%), while Halodule uninervis is the lowest frequency (6,67--20%). Thalassia hemprichii has the highest importance index in Muara Binuangeun (138--300%), while Halodule uninervis has the lowest importance index(4--12%.). The diversity index value in Muara Binuangeun was considered as low (0--0,73), with the dominance index value was high at stations 1 and 2 (1,00), was moderate at station 3 (0,53) and was low in station 4 (0,49). Evenness index values at stations 1 and 2 were considered as low (0), was moderate at station 3 (0,63) and was high at station 4 (0,67). In general, the community structure of seagrass in Muara Binuangeun is unstable because of the diversity and evenness were low, and also dominance were high."

"Penelitian mengenai keragaman mikroalga epifitik di Ciliwung wilayah perbatasan Depok sampai Jakarta Selatan telah dilakukan pada bulan Agustus hingga Desember tahun 2017. Penelitian bertujuan untuk mendeskripsikan keragaman epifitik pada setiap lokasi penelitian dan hubungan dengan parameter lingkungan di setiap lokasi penelitian. Sampel diambil secara purpose random sampling agar dapat mempresentasikan hasil penelitian.Hasil identifikasi sampel diperoleh 28 jenis mikroalga epifitik dengan 5 divisi terdiri atas divisi Chlorophyta, Bacillariophyta, Cyanophyta, Rhodophyta dan Euglenophyta. Frekuensi kehadiran mikroalga epifitik berkisar antara 163-606 jenis mikroalga. Frekuensi kehadiran jenis mikroalga tertinggi pada lokasi pertama yaitu Jembatan Panus dibandingkan dua lokasi lain, sedangkan frekuensi kehadiran jenis mikroalga terkecil di lokasi 3 yaitu TB. Simatupang.

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Research on analysis The diversity of Epiphytic microlagae in Ciliwung of border Depok until Jakarta Selatan was conducted on Agustus and December 2017. The aims of this study was to describe the uniformity of epiphytic miroalgae from research site and the relationship of environmental parameters at each research sites. Samples were taken purposive random sampling.

The indentification result of sample obtained 28 spesies, 5 division consist of divisions of Chlorophyta, Bacillariophyta, Cyanophyta, Rhodophyta and Euglenophyta.The presence frequency of epiphytic microalgae ranges from 163 to 606 cells. The highest frequency of presence of microalgae type in the first location is Panus Bridge compared to two other locations, while the smallest type of microalgae presence at location 3 is TB. Simatupang."

"Penelitian mengenai kelimpahan dan keanekaragaman mikroalga epifit pada Halimeda di Teluk Hurun, Lampung telah dilakukan pada bulan September 2022. Tujuan dari penelitian adalah untuk mengidentifikasi keanekaragaman dan mengetahui kelimpahan jenis mikroalga epifit pada Halimeda di Teluk Hurun, Lampung. Mikroalga epifit diambil dari 10 titik sampling, penghitungan jumlah sel dan identifikasi mikroalga epifit dilakukan dengan metode subsampel di bawah mikroskop. Sepuluh (10) genus mikroalga epifit berasal dari dua kelas, yaitu Bacillariophyceae dan Cyanophyceae. Sepuluh genus tersebut meliputi Synedra, Nitzschia, Cocconeis, Licmophora, Amphipleura, Amphora, Diploneis, Aulacoseira, Cymbella, dan Trichodesmium. Hasil penelitian menunjukan kelimpahan total mikroalga epifit pada Halimeda berkisar antara 12000-39164 sel/mL.

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Research on the abundance and diversity of epiphytic microalgae on Halimeda in Hurun Bay, Lampung has been carried out in September 2022. The purpose of this study was to identify and determine the diversity and abundance of epiphytic microalgae in Halimeda at Hurun Bay, Lampung. Epiphytic microalgae were sampled from 10 sampling points. Cell counting was carried out using the subsample method. Identification of epiphytic microalgae was based on morphological character using a light microscope. The result of study showed that epiphytic microalgae found at Hurun Bay belonged to two classes, namely Bacillariophyceae and Cyanophyceae. Genera were identified, which were Synedra, Nitzschia, Cocconeis, Licmophora, Amphipleura, Amphora, Diploneis, Aulacoseira, Cymbella, and Trichodesmium. The total abundance of epiphytic microalgae in Halimeda ranged from 12000-39164 cells/mL."

"[ABSTRAKbrPenelitian mengenai struktur komunitas diatom epifit pada daun lamun di padang lamun perairan Muara Binuangeun, Banten telah dilakukan pada tanggal 30 April -- 3 Mei 2015. Penelitian bertujuan untuk mengetahui struktur komunitas Diatom epifitik pada daun lamun Thalassia hemprichii (Ehrenb. ex Solms) Asch. antara lain, komposisi genus, kepadatan, dominansi, keanekaragaman, dan kemerataan pada setiap stasiun di Muara Binuangeun, Kabupaten Lebak, Banten. Penentuan lokasi pengambilan sampel dilakukan secara purposive sampling. Hasil penelitian menunjukan bahwa komposisi Diatom epifitik yang diperoleh di lokasi penelitian sebanyak 12 genus dari 4 kelas. Kepadatan Diatom epifitik tiap stasiun berkisar antara 91800 – 420560 sel/ dm2. Nilai indeks dominansi berkisar antara 0,617—0,917 dan tergolong tinggi di setiap stasiun, hal tersebut disebabkan karena terdapat genus Navicula yang mendominasi disetiap stasiun. Nilai indeks keanekaragaman di setiap stasiun penelitian tergolong rendah (berkisar antara 0,25—0,86). Nilai indeks kemerataan berkisar antara 0,1—0,36 dengan stasiun 1 dan 4 tergolong tidak merata, sedangkan pada stasiun 2 dan 3 tergolong kurang merata. Rendahnya nilai indeks keanekaragaman dan kemerataan disebabkan karena adanya tekanan ekologis pada lokasi penelitian. Secara umum, struktur komunitas Diatom epifitik pada lokasi penelitian tergolong tidak stabil karena tingkat dominansi yang tinggi, keanekaragaman yang rendah, dan kemerataan yang tidak merata dan kurang merata.;Research on community structure of epiphyte Diatom on Thalassia hemprichii (Ehrenb. ex Solms) Asch. leaves at seagrass beds Muara Binuangeun Coastal, Kabupaten Lebak, Banten was conducted on 30 April -- 3 May 2015. The aim of this study was to determine community structure of epiphyte Diatom on Thalassia hemprichii (Ehrenb. ex Solms) Asch. leaves include genus composition, abundance, dominance, diversity, and evenness each stations at Muara Binuangeun, Kabupaten Lebak, Banten. Sampling location was determineted by purposive sampling method. Result shows that 4 classis 12 genera Diatom epiphytic composition was obtained . Diatom epiphytic abundance range in each station was 91800 – 420560 sel/ dm2. Dominance index score range was 0,617—0,917 and was classified as high at each stations because genus Navicula dominant in each stations. Diversity index score was classified as low (0,25—0,86) at each stations. Evenness index score range was 0,1—0,36 with station 1 and 4 classifed as highly unevenn and station 2 and 3 was classified as unevenly. Diversity and evenness index score was low because there were ecological pressures. In general, community structure of epiphyte Diatom in research location was unstable because dominance index was high, diversity index was low, and evenness index was highly uneven and unevenly., Research on community structure of epiphyte Diatom on Thalassia hemprichii (Ehrenb. ex Solms) Asch. leaves at seagrass beds Muara Binuangeun Coastal, Kabupaten Lebak, Banten was conducted on 30 April -- 3 May 2015. The aim of this study was to determine community structure of epiphyte Diatom on Thalassia hemprichii (Ehrenb. ex Solms) Asch. leaves include genus composition, abundance, dominance, diversity, and evenness each stations at Muara Binuangeun, Kabupaten Lebak, Banten. Sampling location was determineted by purposive sampling method. Result shows that 4 classis 12 genera Diatom epiphytic composition was obtained . Diatom epiphytic abundance range in each station was 91800 – 420560 sel/ dm2. Dominance index score range was 0,617—0,917 and was classified as high at each stations because genus Navicula dominant in each stations. Diversity index score was classified as low (0,25—0,86) at each stations. Evenness index score range was 0,1—0,36 with station 1 and 4 classifed as highly unevenn and station 2 and 3 was classified as unevenly. Diversity and evenness index score was low because there were ecological pressures. In general, community structure of epiphyte Diatom in research location was unstable because dominance index was high, diversity index was low, and evenness index was highly uneven and unevenly.]"

"Asam dokosaheksanoat (DHA) merupakan asam lemak omega-3 esensial yang berperan penting terhadap kerja otak, jaringan saraf serta retina. Saat ini, mikroalga mendapat perhatian sebagai sumber alternatif yang potensial dalam menghasilkan asam lemak omega-3, yang biasanya didapatkan dari produk ikan. Sebagai sumber DHA konvensional, minyak ikan memiliki kandungan DHA yang rendah, yang dapat memicu penangkapan ikan berlebihan (over fishing) apabila dibutuhkan jumlah DHA yang banyak. Mikroalga Thraustocytrids ditengarai sebagai mikroalga yang sangat potensial dalam menghasilkan DHA.Penelitian ini bertujuan untuk mendapatkan isolat mikroalga Thraustocytrids yang mampu menghasilkan (DHA). Mikroalga Thraustochytrids diisolasi dari guguran daun mangrove yang terletak di Kawasan Mangrove Lampung dengan metode direct planting. Mikroalga yang tumbuh diamati morfologinya dengan mikroskop cahaya. Koloni Thraustochytrids yang tumbuh dipurifikasi hingga dihasilkan koloni tunggal yang selanjutnya diperbanyak dan dibuat biomassanya. Asam lemak diekstraksi dan dimetilasi dengan metode direct transesterification serta diidentifikasi kandungan DHAnya dengan menggunakan Kromatografi Gas- Spektrofotometri Massa.Hasil identifikasi menunjukkan terdapat DHA pada sampel minyak mikroalga Thraustochytrids. Keberadaan DHA dipastikan oleh kecocokan fragmentasi massa DHA sampel dan fragmentasi massa DHA pada database spektrum massa NIST (National Institute of Standards and Technology).

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Docosahexaenoic acid (DHA) is an omega-3 fatty acid that is essential for the proper functioning of the brain, neural tissues and retina. In recent years, microalgae have gained attention as a potential alternative source of omega-3 fatty acid, which are commonly sourced from fish stocks. Fish stocks, as the conventional source of DHA have a very low concentration of DHA, which could bring overfishing issue as an impact of getting a high concentration of DHA. Thraustochytrids is known as a potential microalgae source of DHA.

The purpose of this study is to isolate a Thraustochytrids microalgae that can produce DHA. Thraustochytrids microalgae were isolated from fallen mangrove leaves at Lampung Mangrove Zone with direct planting technique. The morphology of growing microalgae was observed with light microscope. The growing Thraustochytrids colony was purified until a single colony was obtained. The selected colony was cultured and was dried to make its biomass. Fatty acid was extracted and methylated using direct transesterification method. The presence of DHA in microalgae isolate was identified with Gas Chromatography- Mass Spectrophotometer.

The result of DHA identification proved that the isolate of Thraustochytrids microalgae was contained DHA. The presence of DHA in the microalgae oil sample was confirmed by the similarity of DHA mass fragmentation in the sample and DHA mass fragmentation in NIST (National Institute of Standards and Technology) Library Database."