Hasil Pencarian  ::  Simpan CSV :: Kembali

"ABSTRAKUntuk mengetahui pengaruh kondisi lingkungan terhadap struktur komunitas fitoplankton pada musim kemarau di perairan Teluk Ambon telah dilakukan sampling harian selama 30 had dan bulan Januari-Februari 1996 dengan waktu yang tetap, yaitu antara 08.00-10.00 WIT di tiga titik stasiun pengamatan. Parameter lingkungan yang diamati adalah kandungan klorofil-a, suhu perairan, salinitas, fosfat, nitrat, nitrit, oksigen, pH dan turbiditas. Sampling pertama ini diambil pada kedalaman 5 m. Sampling kedua di lima titik pengamatan di perairan Teluk Ambon Dalam, sebanyak empat kali pengamatan dari permukaan sampai kedalaman 20 m.Analisis data menggunakan statistik multivariabel, yaitu berdasarkan analisis komponen utama (Principal Component Analysis) dan analisis faktorial koresponden (Correspondent Analysis). Data sekunder diperoleh dari Badan Meteorologi dan Geofisika, a.l. curah hujan dan prosentase intensitas penyinaran matahari.Pada saat pengamatan, faktor lingkungan yang sangat mempengaruhi struktur komunitas fitoplankton di perairan Teluk Ambon adalah curah hujan. Fitoplankton yang mendominasi adalah dari kelompok diatom marga Chaetoceros. Struktur komunitas fitoplankton baik sebaran secara mendatar (horizontal distribution) dan sebaran tegak (vertical distribution) mempunyai keanekaragaman yang tinggi akibat dinamisnya pergerakan massa air karena pengaruh pasang-surut harian dari Laut Banda. Perairan Teluk Ambon Dalam sangat peka terhadap pengaruh sedimentasi dan pencemaran, untuk itu diperlukan suatu pencegahan pembuangan limbah dan pembukaan lahan secara rasional.

---

ABSTRACT

Ambon Bay is located in the Island of Ambon in the Molluccas. The Bay has a unique oceanographic environment. It has a shallow nentic inner bay (IAB) and a deep oceanic outer bay (0AB), which is strongly influenced by the Banda Sea. The OAB and The lAB are separated by a narrow sill of 15 m depth.

Multivariate Analysis of Community Structure of Phytoplankton And Related Environmental Factors in Ambon Bay. Daily sampling of phytoplankton and enviromental data were carried out at three stations from January to February 1996, between 08.00 to 10.00 p.m., at 5 m depth. The environmental parameters were observed, such as temperature, salinity, phosphate, nitrate, nitrite, dissolved oxygen, pH and turbidity. In dry season, the community structure of phytoplankton in the Ambon Bay water was dominated by diatoms, such as the genera of Chaetoceros, Nifszchia, Rhisozolenia and Bacteriastrum. The abundance of phytoplankton ranged from 1.0 x 102 to 61.350 x 103 cell L-'. Daily fluctuations of phytoplankton diversities were high and diversities among stations were significantly different (p<0.05).

Hydrological conditions in The Ambon Bay were varied. Water temperature ranged from 27.60 to 30.50 °C, salinity ranged from 30 to 32 %, dissolved oxygen ranged from 4.28 to 4.37 ml concentration of phosphate ranged from 0.5 to 1.0 µg at. P04 ?P concentration of nitrate ranged from 0.1 to 1.5 µg at. N03-N L', concentration of nitrite ranged from 0.1 to 0.7 µg at. N02 -N L'', and pH ranged from 6.2 to 7.2. The highest rain fall was recorded at first observation (43.1 mm). The percentage of sun shine ranged from 8 to 100 %. The turbidities ranged from 0.12 to 1.98 NTU. Multivariate analysis shows that rain, turbidity and temperature influenced the community structure of phytoplankton.

Spatial Distribution of Chlorophyll-a And Community Structure of Phytoplankton in Inner Ambon Bay. Weekly sampling of phytoplankton and chlorophyll-a were carried out from January to February 1996, from the surface, 5, 10, 15 and 20 m depth at five stations. The abundance of phytoplankton from the surface to 20 m depth, ranged from 4.5 x 102 to 40.140 x 103 cell Six species of phytoplankton were identified, namely Chaetoceros diversum, Dytilum sot, Liptocylidricus danicus, Nitszchia pacifrca, Plantoniella so! and Noctiluca scinti/ans. Vertical distribution of phytoplankton diversities were heterogeneous. Concentration of chlorophyll-a from the surface to subsurface ranged from 0.196 to 5.044 mg m'. It seems that vertical distribution of chlorophyll-a did not correspond with the abundance of phytoplankton. The abundance of phytoplankton in the Inner Ambon Bay was strongly influenced by the daily tide."

"Musim Timur merupakan musim saat terjadinya proses upwelling di perairan Laut Banda. Informasi adanya effek upwelling terhadap kelimpahan dan distribusi fitoplankton di perairan Laut Banda belum banyak terungkap. Untuk itu dilakukan penelitian pada bulan Agustus 1997 yang mewakili Musim Timur dan bulan Oktober 1998 yang mewakili Musim Peralihan sebagai pembanding. Data kelimpahan dan distribusi fitoplankton dengan mengambil contoh fitoplankton dari kedalaman 100 m ke permukaan menggunakan jaring plankton dengan bukaan mulut berdiamter 31 cm,panjang 120 cm dan ukuran mata jaring 80 µm. Hasil pengamatan pada musim timur (Agustus 1997) proses taikan air (upwelling) masih berlangsung. Hal ini terlihat dari nilai regresi antara suhu dan salinitas (r2 = 84,1 %), suhu dan nitrat (94,5%) Pada saat musim timur tercatat 33 jenis fitoplankton, komposisi jenis fitoplankton lebih bervariasi dibandingkan musim peralihan hanya 26 jenis fitoplankton. Pada musim timur jenis fitoplankton yang mendominasi adalah jenis Chaetoceros sp. Analisis lebih lanjut dengan analisis multivatiate, faktor nitrat mempengaruhi kelimpahan, komposisi dan distribusi fitoplankton.

---

The Effect of Upwelling on Distribution and Abundance of Phytoplankton in Indonesia. East Monsoon is monsoon where upwelling process happened in Banda Sea. Information about upwelling effect to the abundance and distribution of phytoplankton in Banda Sea is not known much.yet. That way has been done the investigation in August 1997 as vice of east monsoon and October 1998 as vice of transition monsoon as comparation.. The abundance and distribution data collected by taken phytoplankton sample in 100 m depth to surface by using plankton net with diameter 31 cm, 120 cm length, and eyes net size 80 µm. The results in east monsoon (August 1997) where (upwelling) still done. This correlation seen from regresi value between temperature and salinity (r2 = 84,1 %), temperature and nitrate (94,5%) In east monsoon recorded 33 phytoplankton species, composition of phytoplankton is varied more compared to transition monsoon where found 26 phytoplankton species only. In east monsoon dominance phytoplankton is Chaetoceros sp. Further analysis by using multivariate analysis, nitrate factor affect to abundance, composition, and distribution of phytoplankton."

"Telah diketahui bahwa perairan Laut Banda sangat dipengaruhi oleh faktor musiman yang mempengaruhi kondisi fitoplankton. Tetapi informasi kondisi fitoplankton, khusus kelompok Cyanobacteria pada Musim Peralihan belum banyak terungkap. Untuk itu dilakukan penelitian pada bulan Oktober 1998 dan November 1999 yang dianggap mewakili Musim Peralihan dengan mengambil contoh fitoplankton dari permukaan sampai kedalaman 200 m untuk mengetahui kelimpahan, komposisi dan distribusi Cyanobacteria.Kelimpahan Trichodesmium erahtraeum berkisar antara 0,02-1,2 x 102 koloni m-3, nilai tertinggi dijumpai di kedalaman 100 m dan terendah di kedalaman 200 m. Kelimpahan Trichodesmium thiebautii berkisar antara 0-8,8 x 102 sel m-3. Distribusi Trichodesmium erythraeum dijumpai pada kedalaman 50 m kelimpahannya relatif tinggi yang dipengaruhi oleh kondisi nitrat perairan (r2 =28,30 %) dan suhu perairan (r2 =17,30 %). Berdasarkan kelimpahan, keanekaragaman, kemerataan dan distribusinya Trichodesmium eryhtraeum dan Trichodesmium thiebautii mendominasi pada musim peralihan.

---

Domination of Cyanobacteria at Transition Monsoon around Banda Sea Area. Banda Sea had affected by monsoon factor, this condition also influenced fitoplankton condition, but information about fitoplankton condition especially Cyanobacteria group still not complete yet. Therefore had done the researched about fitoplankton in October 1998 and November 1999, that months is regarded as vice of transition monsoon. Fitoplankton samples were taken from the surface to 200 m depth to known the abundant, composition, and distribution of Cyanobacteria.The results showed that the abundant of Trichodesmium erahtraeum varied between 0.02-1.2 x 102 coloni m-3, the highest vale found in 100 m depth and the lowest in 200 m depth. The abundance of Trichodesmium thiebautii varied between 0-8.8 x 102 cel m-3. Distribution of Trichodesmium erythraeum found until 50 m depth, their abundance high relative, this condition caused by nitrate concentration (r2 =28,30 %) and temperature (r2 =17,30 %). Based on their abundance, diversity, evenness and distribution Trichodesmium eryhtraeum dan Trichodesmium thiebautii dominated in transition monsoon."

"ABSTRACTSince the Jakarta Bay is economically important for various stake holders, then understanding the eutrophication processes, condition and its status, in the past, present time, and in the future through scientific research is inevitable.The objectives of this research are (1) To analyze the water quality parameters that can be used as an indicator of eutrophication phenomenon, (2) To develop monitoring tools for observing eutrophication process, and (3) To assess the tendency of eutrophication in the future using ASSETS (Assessment of Estuarine Trophic Status) model.The method used in this research is marine remote sensing techniques through the application of multi-temporal and multi-sensor of Landsat satellites data. Results from field sampling of water quality data indicated that the mean of water transparency were stable during 1970?s to 1990?s around 7.5 m, but sharply decreased to 3.8 m in 2000?s On the other hand, the mean chlorophyll-a concentration showed a reversal pattern from water transparency, that the concentration was rapidly increased from 1.71 to 7.8 g/m3 during 1970?s to 2000?s. Based on these data, eutrophication is occuring in the Jakarta Bay.Empirical model for predicting water transparency developed using multitemporal Landsat-7 ETM+ data and field data collected in 2004 indicated that the model was good and capable to predict water transparency. The model was applied to both old Landsat aquired in 1970?a (Landsat-1, 2 and 3 MSS), 1980?s (Landsat-4 and 5 MSS and TM), and 1990?s (Landsat-5 and 7, TM and ETM+), as well as the latest data of 2000?s (Landsat-7 ETM+). Maps of water transparency and Trophic State Indeks (TSI) derived from emprical predicting model indicated a decreasing tendency of water transparency from 7.5 to 4.0 m during the 1970?s to 2000?s with the higest decreasing rate from 1980?s to 2000?s, while the TSI showed an oligotrophic condition during 1970?s to 1980?s, but move to mesotrhopic condition in 1990, and decreasing to eutrophic and hypertrophic condition in 2000?s. Thus, all these facts proved that the eutrophication is still going from the past to the present time. Utilization of ASSETS model for knowing the eutrophication of Jakarta Bay in the future based on several input parameters showed that strong eutrophicatiom will be continued in the future in which caused worsen condition of the water quality."