Bakteri Memegang Peran Penting Sebagai Pengurai Di Dalam Sedimen Dan Meningkatkan Pertumbuhan Produksi Tanaman Sehubungan Dengan Kemampuannya Mengikat N2 Dari Udara Dan Mengubah Ammonium Menjadi Nitrat. Tujuan Penelitian Ini Adalah Untuk Mengidentifikasi Bakteri Yang Terdapat Pada Sedimen Berdasarkan Kedalaman 10 Cm, 20 Cm Dan 30 Cm Serta Menguji Kualitas Air Pada Perairan Danau Di Kawasan Danau Manuk Bungkul Kecamatan Sembakung Kabupaten Nunukan. Penelitian Ini Dilaksanakan Pada Bulan September – Desember 2019. Metode Yang Digunakan Yaitu Identifikasi Morfologi,, Deskriptif Dan Kuantitatif Dengan Mendeskripsikan Keanekaragaman Bakteri Pada Sedimen Berdasarkan Kedalaman Disetiap Stasiun Penelitian. Pengambilan Sampel Dilakukan Di Kawasan Danau Manuk Bungkul Dengan Pengambilan Sampel Di 3 Titik Stasiun Yaitu Daerah Hulu Danau, Tengan Danau Dan Hilir Danau. Identifikasi Bakteri Dilakukan Di Laboratorium Balai Karantina Ikan Pengendali Mutu Dan Keamanan Hasil Perikanan Tarakan. Hasil Penelitian Menunjukkan Keanekaragaman Bakteri Pada Sedimen Sebanyak 3 Genus Bakteri Yaitu Aeromonas Sp., Actinobacillus Sp., Dan Bacillus Sp., Dengan Genus Yang Dominan Ditemukan Yaitu Bacillus Sp. Pada Kedalaman 10 Cm Terdapat 2 Genus Bakteri Yaitu Aeromonas Sp., Dan Bacillus Sp., Kedalaman 20 Cm Terdapat 2 Genus Bakteri Aeromonas Sp Dan Kedalaman 30 Cm Terdapat 3 Genus Bakteri Yaitu Actinobacillus Sp, Aeromonas Sp, Dan Bacillus Sp.
Kata Kunci: Bakteri, Danau Manuk Bungkul, Identifikasi, Sedimen

Bacteria Play An Important Role As Decomposers In Sediment And Increase The Growth Of Plant Production Due To Their Ability To Bind N2 From The Air And Convert Ammonium Into Nitrate. The Purpose Of This Study Was To Identify The Bacteria Present In The Sediment Based On A Depth Of 10 Cm, 20 Cm And 30 Cm And To Check The Air Quality Of The Lake Waters In The Manuk Bungkul Lake Area, Sembakung District, Nunukan Regency. This Research Was Conducted In September - December 2019. The Methods Used Were Morphological, Descriptive And Quantitative By Describing The Diversity Of Bacteria In The Sediment Based On The Depth Of Each Research Station. Sampling Was Carried Out In The Lake Manuk Bungkul Area By Taking Samples At 3 Station Points, Namely The Upstream Area Of The Lake, The Middle Of The Lake And The Downstream Of The Lake. The Identification Of Bacteria Was Carried Out At The Laboratory Of The Fish Quarantine Center For Quality Control And Safety Of Fishery Products In Tarakan. The Results Showed That The Diversity Of Bacteria In The Sediment Was 3 Genera Of Bacteria, Namely Aeromonas Sp., Actinobacillus Sp., And Bacillus Sp., With The Dominant Genus Found, Namely Bacillus Sp. At A Depth Of 10 Cm There Are 2 Genera Of Bacteria, Namely Aeromonas Sp., And Bacillus Sp., 20 Cm Deep There Are 2 Genera Of Aeromonas Sp And 30 Cm Depth There Are 3 Genera Of Bacteria, Namely Actinobacillus Sp, Aeromonas Sp, And Bacillus Sp. Keywords: Bacteria, Manuk Bungkul Lake, Identification, Sediment