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Hikmah Thoha
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TEMPORAL VARIATION IN CERATIUM SPP. ABUNDANCE RECORDED IN JAKARTA BAY Thoha, Hikmah
Marine Research in Indonesia Vol 37, No 1 (2012)
Publisher : Research Center for Oceanography - Indonesian Institute of Sciences (LIPI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1639.824 KB) | DOI: 10.14203/mri.v37i1.35

Abstract

Ceratium is non-toxic dinoflagellate which has been regarded as the most common bloom-forming species in the coastal waters around the world. Eventhough research and monitoring on phytoplankton In Jakarta Bay have been conducted for long enough, no specific attention has been given to Ceratium community. Therefore, a research was set up in order to understand the dynamic of Ceratium population and its regulating factors. A serial sampling was conducted in 10 stations during 2009 and 2010. Phytoplankton was sampled in horizontal towing using Kitahara plankton net (80 μm mesh size, 0.5 m mouth diameter and 1m length). Phytoplankton enumeration and identification were done by applying Fraction Method on Sedgewick Rafter Counting Chamber (SRCC). The result showed clear temporal variations in Ceratium absolute density, relative density, relative frequency and importance value. When phytoplankton bloomed in August 2009, no Ceratium bloom observed. High density of Ceratium was observed in November 2009 and May 2010, but it contributed relatively small proportion to phytoplankton as a whole (relative density <1%). Due to its low density and relatively limited distribution in Jakarta Bay, Ceratium may demonstrate limited ecological role to the phytoplankton community.
TEMPORAL VARIATION IN CERATIUM SPP. ABUNDANCE RECORDED IN JAKARTA BAY Thoha, Hikmah
Marine Research in Indonesia Vol 37 No 1 (2012)
Publisher : Research Center for Oceanography - Indonesian Institute of Sciences (LIPI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1639.824 KB) | DOI: 10.14203/mri.v37i1.35

Abstract

Ceratium is non-toxic dinoflagellate which has been regarded as the most common bloom-forming species in the coastal waters around the world. Eventhough research and monitoring on phytoplankton In Jakarta Bay have been conducted for long enough, no specific attention has been given to Ceratium community. Therefore, a research was set up in order to understand the dynamic of Ceratium population and its regulating factors. A serial sampling was conducted in 10 stations during 2009 and 2010. Phytoplankton was sampled in horizontal towing using Kitahara plankton net (80 μm mesh size, 0.5 m mouth diameter and 1m length). Phytoplankton enumeration and identification were done by applying Fraction Method on Sedgewick Rafter Counting Chamber (SRCC). The result showed clear temporal variations in Ceratium absolute density, relative density, relative frequency and importance value. When phytoplankton bloomed in August 2009, no Ceratium bloom observed. High density of Ceratium was observed in November 2009 and May 2010, but it contributed relatively small proportion to phytoplankton as a whole (relative density &lt;1%). Due to its low density and relatively limited distribution in Jakarta Bay, Ceratium may demonstrate limited ecological role to the phytoplankton community.
PUBLIC AWARENESS ON HARMFUL ALGAL BLOOM (HAB) IN LAMPUNG BAY Aditya, Vishnu; Koswara, Asep; Fitriya, Nurul; Rachman, Arief; Sidabutar, Tumpak; Thoha, Hikmah
Marine Research in Indonesia Vol 38 No 2 (2013)
Publisher : Research Center for Oceanography - Indonesian Institute of Sciences (LIPI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (926.212 KB) | DOI: 10.14203/mri.v38i2.58

Abstract

Harmful algal blooms (HABs) cause various problems, such as water quality degradation, fauna mass mortality and impairment of human health. Water quality monitoring in Lampung Bay has been conducted by Lampung Marine Aquaculture Office (BBL) of the Ministry of Marine Affairs and Fisheries since 1994. Occurrence of Pyrodinium bahamense var. compressum (Pbc), a causative organism of paralytic shellfish poisoning (PSP), has been recorded but threats caused by HABs have never been reported. A study aimed to know the level of public knowledge and awareness about HABs in Lampung Bay has been conducted. The components of group respondents consisted oflocal governments, academics and coastal communities. Awareness from each component was examined includinggeneral HAB knowledge, HAB impact to the community, HAB occurence and local knowledge of HAB. Data of HAB knowledge were collected through questionnaire and focus group  discussion. The result showed that 40.5% of respondents had knowledge of HABs phenomena and 51.3% respondents only know signs or indicators of HAB occurrence, while only 1.4% respondents had knowledge of local HAB occurences. The direct impact of HABs to the community was not commonly known by the respondents. Only a few cases of poisoning after eating seafood were reported. It can be concluded that there was lack of public knowledge and awareness on HABs in LampungBay. Intensive public awareness programs about HABs should be conducted in order to reduce risk towards HABs in Lampung Bay.
SEASONAL CHANGE IN THE DIEL PATTERN OF THE PSEUDO-NITZSCHIA POPULATION IN THE CISADANE RIVER ESTUARY: RESPONSE TO THE CHANGES IN THE WATER’S PHYSICAL-CHEMICAL PARAMETERS Rachman, Arief; Thoha, Hikmah
Marine Research in Indonesia Vol 39 No 1 (2014)
Publisher : Research Center for Oceanography - Indonesian Institute of Sciences (LIPI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1937.606 KB) | DOI: 10.14203/mri.v39i1.83

Abstract

Seasonal changes of Pseudo-nitzschia diel dynamics in an estuarine ecosystem have been known to be regulated by salinity, water temperature and nutrient dynamics. In this study, we aimed to investigate the effect of these physical-chemical factors on the diel pattern of the Pseudo-nitzschia population in the Cisadane River estuary.Plankton samples were collected from a diel station at two different periods, in the dry season (May-June) and thewet season (September). Plankton samplings were done in a 24 hour period with 3 hourly sampling intervals. The result showed a higher abundance of Pseudo-nitzschia in the dark-period during the dry season, while during the wet season the abundance was higher in the light-period. Nitrate and phosphate concentrations were suggested as important factors in facilitating Pseudo-nitzschia maxima. The low abundance of Pseudo-nitzschia in the estuarycould be due to the relatively low N:P ratio (&lt;10). The results showed that the Cisadane River estuary was strongly influenced by seawater during the night and by freshwater during day. The GLM analysis suggested that there were changes in the species omposition of the Pseudo-nitzschia population in the ecosystem. The oligohaline species was found to be abundant in the dry season, the maxima occurred at night, which is probably related to a highermarine influence in the ecosystem. Conversely the polyhaline species was abundant in the wet season, with the maxima occurring during daylight, which might be related to a stronger freshwater influence in the ecosystem.
Hubungan Kandungan Klorofil-A dan Kelimpahan Fitoplankton di Perairan Berau Kalimantan Timur Aryawati, Riris; Thoha, Hikmah
Maspari Journal : Marine Science Research Vol 2, No 1 (2011): Edisi Januari
Publisher : UNIVERSITAS SRIWIJAYA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (517.093 KB) | DOI: 10.36706/maspari.v2i1.1292

Abstract

Phytoplankton is the most important primary producers in all marine invironments. Primary production, a term interchangeable with photosynthesis, is the biological process of creating high-energy organic material from CO2, H2O, and other nutrients using solar energy. The aim of the research was to know the relationship of   abundance of phytoplankton and chlorophyl-a in Berau waters, East Kalimantan. The result of physical-chemical water measurement are generally inaccordance for phytoplankton living purposes. The number of phytoplankton genera found during research was 28 genera which consist of 24 kinds Bacillariophyceae and 4 kinds Dinophyceae. Community structure was dominated by the group of diatoms such as Chaetoceros, Dytilum, Thalassiothrix. Abundance of phytoplankton influences of content klorofil-a, although not too big.   Keywords: chlorophyl-a, abundance, phytoplankton, Berau waters ABSTRAK   Fitoplankton merupakan produsen primer terpenting di lingkungan laut,  karena fitoplankton mampu berfotosintesis. Fotosintesis adalah suatu proses yang kompleks, dimana sinar matahari diserap oleh sel-sel fitoplankton dan diubah menjadi energi biologi kemudian disimpan dalam bentuk senyawa organik. Tujuan dari penelitian ini adalah mengetahui hubungan antara kandungan klorofil-a dengan kelimpahan fitoplankton di perairan pesisir Berau, Kalimantan Timur. Penelitian ini dilaksanakan pada bulan September 2005. Sampel air laut diambil dengan botol Nansen lalu dimasukkan dalam botol sampel untuk selanjutnya disimpan dalam kotak pendingin  untuk dianalisis kandungan klorofil-a, fosfat, dan nitrat. Pada saat pengambilan sampel juga dilakukan pengukuran parameter oseanografi seperti suhu, salinitas, arah dan kecepatan arus. Sampel fitoplankton diambil dengan menggunakan jaring kitahara yang berbentuk kerucut dengan diameter 31 cm dan mata jaring 80 μm. Untuk mengetahui hubungan antara kandungan klorofil-a dengan kelimpahan fitoplankton digunakan analisis regresi korelasi. Hasil penelitian menunjukkan bahwa fitoplankton yang ditemukan terdiri dari 28 genera yang termasuk dalam dua klas, yaitu Bacillariophyceae (24 genera) dan Dynophyceae (4 genera). Bacillariophyceae mempunyai    jumlah  terbesar, baik dari segi jumlah generanya maupun jumlah individu tiap generanya. Genera fitoplankton yang dijumpai dalam jumlah melimpah (>10%) adalah Chaetoceros, Dytilum, dan Thalassiothrix. Kelimpahan fitoplankton mempengaruhi besarnya kandungan klorofil-a, walaupun tidak terlalu besar.   Kata kunci: klorofil-a, kelimpahan, fitoplankton, perairan Berau
IDENTIFICATION OF SOME STRAINS OF DINOFLAGELLATES BASED ON MORPHOLOGY AND MOLECULAR ANALYSIS Thoha, Hikmah
Makara Journal of Science Vol. 12, No. 2
Publisher : UI Scholars Hub

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Abstract

Dinoflagellates are the important primary producers in aquatic environments. In oceans, they play interesting role in ecological functions such as red tide forming organisms, symbiont of coral reef or sea anemone and DSP (Diarrhetic Shellfish Poisoning) or PSP (Paralytic Shellfish Poisoning) producing organisms. Morphology and molecular analysis of dinoflagellates were conducted on November 2002 to March 2003. The phylogenetic studies based on 18S rDNA analyses, sequence have begun to appear more frequently in the literature, as attention has turned to relationships within the major eukaryotic lineages, particular importance for the taxonomy of the armored and unarmored genera of dinoflagellates (Gyrodinium sp., Cachonina sp., Gymnodinium sp., Amphidinium sp.), because many of the genera cause extensive plankton blooms, fish kills and other harmful events, were studied used to amplify 18S rDNA, present in the total DNA extracted from algal pellet. The amplify approximately 1400 bp of the nuclear-encoded LSU rDNA gene using terminal primeirs DIR, products were cheked by 1.0 % agarose gel electrophoresis, then cloning with TA cloning KIT. Sequencing were analyzed by the GENETIX Mac Software, Homology search by Blast and Phylogenetic analysis. Results of hylogenetic analysis of 18S rDNA are: Strain no. 10893 (un identified) from the genera, it is belonging Gymnodinium or Polarella. Strain no. 10795 is closely related other species Cachonina hallii. We tentatively named strain no 11151 and 11160 similar to Gyrodinium or Gymnodinium based on morphology, but these strain indepently position in this tree and is not a real of Gymnodinium sensu stricto. It is possible, we can establish the new genera for strain no. 11151; 11160 because this not cluster any other unarmored species.
IDENTIFICATION OF SOME STRAINS OF DINOFLAGELLATES BASED ON MORPHOLOGY AND MOLECULAR ANALYSIS Thoha, Hikmah
Makara Journal of Science Vol. 11, No. 2
Publisher : UI Scholars Hub

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Abstract

Dinoflagellates are the important primary producers in aquatic environments. In oceans, they play interesting role in ecological functions such as red tide forming organisms, symbiont of coral reef or sea anemone and DSP (Diarrhetic Shellfish Poisoning) or PSP (Paralytic Shellfish Poisoning) producing organisms. Morphology and molecular analysis of dinoflagellates were conducted on November 2002 to March 2003. The phylogenetic studies based on 18S rDNA analyses, sequence have begun to appear more frequently in the literature, as attention has turned to relationships within the major eukaryotic lineages, particular importance for the taxonomy of the armored and unarmored genera of dinoflagellates (Gyrodinium sp., Cachonina sp., Gymnodinium sp., Amphidinium sp.), because many of the genera cause extensive plankton blooms, fish kills and other harmful events, were studied used to amplify 18S rDNA, present in the total DNA extracted from algal pellet. The amplify approximately 1400 bp of the nuclear-encoded LSU rDNA gene using terminal primeirs DIR, products were cheked by 1.0 % agarose gel electrophoresis, then cloning with TA cloning KIT. Sequencing were analyzed by the GENETIX Mac Software, Homology search by Blast and Phylogenetic analysis. Results of hylogenetic analysis of 18S rDNA are: Strain no. 10893 (un identified) from the genera, it is belonging Gymnodinium or Polarella. Strain no. 10795 is closely related other species Cachonina hallii. We tentatively named strain no 11151 and 11160 similar to Gyrodinium or Gymnodinium based on morphology, but these strain indepently position in this tree and is not a real of Gymnodinium sensu stricto. It is possible, we can establish the new genera for strain no. 11151; 11160 because this not cluster any other unarmored species.
KELIMPAHAN PLANKTON DI EKOSISTEM PERAIRAN TELUK GILIMANUK, TAMAN NASIONAL, BALI BARAT Thoha, Hikmah
Makara Journal of Science Vol. 11, No. 1
Publisher : UI Scholars Hub

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Abstract

Plankton abundance in Gilimanuk Bay of National Park Ecosystem, West Bali. An observation of plankton condition in Gilimanuk Bay of National Park, West Bali was conducted during March 2006. This study aimed to observ the environmental quality of Gilimanuk Bay water. The parameters observed were focused on the phytoplankton and zooplankton communities. Ten points of observation was done. Plankton abundance varied with location group from 4428 to 1716224 sel/m3 and 23938 individu/m3 (67.73 %) for microplankton and macroplankton, respectively. Microplankton community structure was dominated by the group of diatoms, such as Coscinodiscus, Chaetoceros, Guinardia, Navicula. Pseudonitzshia. The genus Ceratium (the group of dinoflagellates) was found in relatively abundant, but still normal condition. The structure of macroplankton was dominated by copepods 23938 individu/m3 (67.73 %). The other hand, information about mangrove, sea grass and coral reef and asssosiation with fauna in these ecosystem of Gilimanuk Bay very rarely. We need observed this subject for base line data to improving management of marine resources development.
PENGARUH MUSIM TERHADAP PLANKTON DI PERAIRAN RIAU KEPULAUAN DAN SEKITARNYA Thoha, Hikmah
Makara Journal of Science Vol. 7, No. 2
Publisher : UI Scholars Hub

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Abstract

Seasonal influenzed on plankton of the waters around Riau islands. The observation was conducted during April - May 2002. This study was done in relation with observation on environment quality of the waters around Riau Islands. The parameter observed were focus on the plankton communities for tweentyfives points of stations which were grouped into two zone based on the distance of the each station. Plankton abundance varied with location groups from 50- 90 % respectively. Community structure was dominated by the group of diatoms such as Chaetoceros, Dytilum, Nitzschia, Thalassionema, Thalassiothrix and the genus Ceratium (the group of Dinoflagellata). Community structure of zooplankton was dominated by the group of Copepods (45 – 90 %) and Polychaeta, Chaetognata, Bivalvia, Gastropods and Oikopleura (more than 90 %). The results describe the relationship between the water environmental condition and variation of plankton condition
IDENTIFICATION OF SOME STRAINS OF DINOFLAGELLATES BASED ON MORPHOLOGY AND MOLECULAR ANALYSIS Thoha, Hikmah
Makara Journal of Science Vol. 12, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Dinoflagellates are the important primary producers in aquatic environments. In oceans, they play interesting role in ecological functions such as red tide forming organisms, symbiont of coral reef or sea anemone and DSP (Diarrhetic Shellfish Poisoning) or PSP (Paralytic Shellfish Poisoning) producing organisms. Morphology and molecular analysis of dinoflagellates were conducted on November 2002 to March 2003. The phylogenetic studies based on 18S rDNA analyses, sequence have begun to appear more frequently in the literature, as attention has turned to relationships within the major eukaryotic lineages, particular importance for the taxonomy of the armored and unarmored genera of dinoflagellates (Gyrodinium sp., Cachonina sp., Gymnodinium sp., Amphidinium sp.), because many of the genera cause extensive plankton blooms, fish kills and other harmful events, were studied used to amplify 18S rDNA, present in the total DNA extracted from algal pellet. The amplify approximately 1400 bp of the nuclear-encoded LSU rDNA gene using terminal primeirs DIR, products were cheked by 1.0 % agarose gel electrophoresis, then cloning with TA cloning KIT. Sequencing were analyzed by the GENETIX Mac Software, Homology search by Blast and Phylogenetic analysis. Results of hylogenetic analysis of 18S rDNA are: Strain no. 10893 (un identified) from the genera, it is belonging Gymnodinium or Polarella. Strain no. 10795 is closely related other species Cachonina hallii. We tentatively named strain no 11151 and 11160 similar to Gyrodinium or Gymnodinium based on morphology, but these strain indepently position in this tree and is not a real of Gymnodinium sensu stricto. It is possible, we can establish the new genera for strain no. 11151; 11160 because this not cluster any other unarmored species.
Co-Authors Aditya, Vishnu Arief Rachman Koswara, Asep Nurul Fitriya Riris Aryawati Tumpak Sidabutar