BIOFASIES DAN EKOLOGI PERAIRAN JAWA TENGAH BAGIAN UTARA BERDASARKAN KUMPULAN FORAMINIFERA BENTIK KECIL
Abstract
Daerah penelitian merupakan bagian dari Laut Jawa terletak di Perairan Jawa Tengah bagian Utara. Laut Jawa dibatasi oleh tiga pulau besar sehingga kondisi Laut Jawa menjadi tertekan karena memperoleh kontribusi air dan sedimen dari ketiga pulau tersebut. Tujuan dari penelitian ini adalah untuk menentukan biofasies dan kondisi ekologi dari daerah penelitian berdasarkan kumpulan foraminifera bentik kecil. Foraminifera bentik kecil adalah hewan laut uniseluler bercangkang yang hidup di atas atau di dalam sedimen dasar laut. Kehidupannya sangat dipengaruhi oleh lingkungan sehingga foraminifera dapat digunakan sebagai indikator lingkungan. Analisis kuantitatif dilakukan pada 32 sampel sedimen dengan cara mengumpulkan data foraminifera bentik kecil berukuran 0,125 mm pada setiap satu gram sampel sedimen kering. Berdasarkan analisis kluster, daerah penelitian terbagi menjadi 4 biofasies yaitu Biofasies I (Zona Litoral-Zona Paparan dalam), Biofasies IIa (Zona Paparan dalam), Biofasies IIb (Zona Litoral-Zona Paparan dalam) dan Biofasies III (Zona Paparan dalam). Selanjutnya, nilai indeks diversitas dari keempat biofasies tersebut berkisar antara 0,7 – 1,1. Keempat biofasies dan nilai indeks diversitas menunjukkan daerah penelitian merupakan lingkungan laut dangkal dengan tekanan ekologis sedang sampai tinggi.
Kata Kunci: foraminifera bentik kecil, biofasies, indeks diversitas, laut dangkal, ekologi, Perairan Jawa Tengah bagian Utara.
The research area is part of the Java Sea located in the northern part of Central Java. Java Sea is surrounded by three large islands. Therefore, its condition becomes depressed because of the contribution of water and the sediment from the three islands. The purpose of the study is to determine the biofacies and ecological conditions of the research area based on small benthic foraminifera assemblages. The small benthic foraminifera are unicellular sea shell animals that live on or within the sediment of the seabed. Its life is severely influenced by the environment so that the foraminifera can be used as environmental indicators. Quantitative analysis was carried out on 32 sedimentary samples by collecting of 0.125 mm benthic foraminifera on each one gram of dried samples. Based on the cluster analysis, the research area is divided into 4 biofacies i.e. Biofacies I (Littoral Zone-Inner Shelf Zone), Biofasies IIa (Inner Shelf Zone), Biofacies IIb (Littoral Zone-Inner Shelf Zone) and Biofacies III (Inner Shelf Zone). Furthermore, the range diversity index value of all biofacies is 0. 7 – 1.1. It can be concluded that the all biofacies and diversity index value shows the research area is shallow sea with medium stress to highly stress ecology.
Key words: small benthic foraminifera, biofacies, diversity index, shallow sea, ecology, northern Central Jawa waters
Keywords
Full Text:
PDF (Bahasa Indonesia)References
Armstrong, H.A. dan Brasier, M.D. 2005. Microfossils. 2nd ed. Blackwell Publishing.
Bakus, G.J., 1990. Quantitative Ecology and Marine Biology. A.A. Balkema/Rotterdam; hal. 57.
Barker, R.W. 1960. Taxonomic Notes. Society of Economic Paleontologists & Mineralogists. Special Publication No.9. Tulsa., Oklahoma, USA.
Boltovskoy, E. dan Wright, R., 1976. Recent Foraminifera. Dr. W.Junk b.v. publishers the Hague; hal. 513.
Haq, B.U. dan Boersma, A., 1998. Introduction to Marine Micropaleontology. Elsevier Science (Singapore) Pte. Ltd. Singapore; hal. 19-77.
Jones, R. W., 2014. Foraminifera and Their Applications. Cambridge University Press. United Kingdom.
Jones, R.W. 1994. The Challenger Foraminifera. Oxford University Press. New York. USA; 150 hal.
Jurnaliah, L. 2013. Variasi Komposisi Dinding Cangkang Foraminifera Bentonik Kecil Resen Perairan Semarang (Lembar 1409), Jawa Tengah. Vol. 11, no. 1 April, Bulletin of Scientific Contribution. Fakultas Teknik Geologi. Universitas Padjadjaran; hal.11-15.
Jurnaliah, L. 2014. Hubungan antara Jenis Substrat Dengan Foraminifera Bentonik Kecil Resen Perairan Semarang, Jawa Tengah. Prosiding Seminar Nasional Fakultas Teknik Geologi, Universitas Padjadjaran, 24 Mei 2014. Bandung.
Lewis, D. 2006. Modern & Recent Seafloor Environments (Sedimentary, Foraminiferal & Ostracode) of The Pitt Water Estuary, South-East Tasmnia. (Thesis Master). School of Earth Sciences. University of Tasmania. Hobart; hal. 98.
Loeblich, A. R., dan Tappan, H., 1994. Foraminifera of the Sahul Shelf and Timor Sea. Special Publication no. 31. Cushman Foundation For Foraminiferal research Inc. Department of Invertebrate Paleontology. Harvard University. Cambridge, USA; 661 hal.
Murray, J. W. 2006. Ecology & Applications of Benthic Foraminifera. Cambridge University Press. UK; hal. 327-343.
Murray, J., dan Rohling, E. J., 2012. Foraminifera. Diakses dari https://www.noc.socton. ac.uk. National Oceanography Centre Southampton
Nagara, G.A., Sasongko, N.A., dan Olakunle, O.J. 2007. Introduction to Java Sea. Oceanography-University of Stavanger. Nugrohoadi.files.wordpress.com/2008/ 02 /introduction-to-java-sea-oceanography-uis-2007.final.pdf
Nurani, R., Jurnaliah, L., dan Winantris. 2014. Penentuan Spesies Foraminifera Bentonik Kecil Dominan Pada Perairan Semarang, Provinsi Jawa Tengah. Vol. 12, no. 1, April, Bulletin of Scientific Contribution. Fakultas Teknik Geologi. Universitas Padjadjaran; hal.1- 7.
Peta Perairan Semarang. Diakses dari http://www.google.co.id/maps/search/peta+perairan+semarang/
Rai, A.K. & Singh, V.B. 2012. Response of Eastern Indian Ocean (ODP Site 762B) Benthic Foraminiferal Assemblages to The Closure of Indonesian Seaway. Oceanologia, 54(3). 449-472. Polish Academy of Sciences, Institute of Oceanology. Doi:10.5697/00.54-3.449.
Suhartati, M.N.dan Rubiman 2010. Distribusi Foraminifera Bentik Resen Di Laut Arafura. Jurnal Ilmu Dan Teknologi Kelautan Tropis. vol.2., No.2; hal. 74-82
Yusuf, M. dan Yanagi, T. 2013. Numerical Modelling of Tidal Dynamics in The Java Sea Coastal Marine Science. 36(1): 1-12. Repository.dl.itc.u-tokyo.ac.jp/dspace/
DOI: http://dx.doi.org/10.32693/jgk.17.2.2019.614
Refbacks
- There are currently no refbacks.