Journal of Aceh Aquatic Science Available online at: Volume 5, Nomor 2, 2021 http://jurnal.utu.ac.id/JAAS/issue/archive ISSN: 2580-264X, E-ISSN: 2745-7230 15 STRUKTUR KOMUNITAS FITOPLANKTON DI PERAIRAN DAM RAMAN, METRO, LAMPUNG PHYTOPLANKTON COMMUNITY STRUCTURE IN DAM RAMAN, METRO, LAMPUNG Putu Cinthia Delis, Aulia Insani, Herman Yulianto, Rara Diantari Program Studi Sumberdaya Akuatik, Jurusan Perikanan dan Kelautan, Fakultas Pertanian, Universitas Lampung. Korespondensi : putu.delis@fp.unila.ac.id Abstract Dam Raman is a reservoir located in the Metro City of Lampung. These waters used for activities such as aquaculture (KJA) and tourism activities. The input of organic matter from aquaculture (KJA) and tourism activities can trigger eutrophication. Phytoplankton are organisms that are sensitive to changes in water quality and have an important role as the basis of the food chain. The purpose of this study was to examine the abundance and community structure of phytoplankton in the Dam Raman. The research was conducted in January – March 2020. Samples were taken from four research observation stations. The data collected include water quality, species composition and abundance of phytoplankton, diversity index, similarity index, and dominance index. The results of the observations showed that there were 7 classes of phytoplankton. These classes include Chlorophyceae, Chrysophyceae, Cyanophyceae, Bacillariophyceae, Euglenophyceae, Rhodophyceae, and Xantophyceae. The abundance of phytoplankton ranged from 116-7278 cells/L. Phytoplankton diversity in Dam Raman is high with moderate community stability with values ranging from 2.89 to 3.33 and there is no indication of the dominance of certain types of phytoplankton. Keywords: KJA, Abundance, Diversity, Dominance, Organic matter I. Pendahuluan Dam Raman merupakan waduk berukuran 26 ha yang terletak di utara Kota Metro, Provinsi Lampung. Tujuan utama dibangunnya Dam Raman adalah sebagai sumber pengairan ladang dan persawahan di tiga kabupaten, yaitu Lampung Tengah, Lampung Timur, dan Kota Metro. Sumber air Dam Raman berasal dari aliran Sungai Way Bunut dan Way Raman. Aliran Sungai Way Bunut melewati komplek industri kelapa sawit serta daerah pemukiman warga, sedangkan aliran Sungai Way Raman melewati areal persawahan. Seiring perkembangannya, saat ini Dam Raman juga mulai dimanfaatkan oleh masyarakat setempat sebagai lokasi budidaya ikan dan juga lokasi pariwisata. Kegiatan budidaya ikan di DAM Raman menggunakan sistem KJA dengan