Kandungan bahan organik Karbon (C), Nitrogen (N), dan Fosfor (P) pada sedimen berperan sebagai proses fotosintesis, respirasi, serta pembentuk protein bagi tanaman. Tujuan penelitian adalah untuk mengetahui kandungan bahan organik Karbon (C), Nitrogen (N), dan Fosfor (P) pada sedimen berdasarkan kedalaman10 cm, 20 cm, dan 30 cm di Kawasan Danau Manuk Bungkul Kecamatan Sembakung Kabupaten Nunukan. Penelitian ini dimulai pada bulan September 2019 sampai dengan Januari 2020 metode yang digunakan dalam penelitian ini yaitu deskriptif kuantitatif dengan mendeskripsikan kandungan Karbon (C), Nitrogen (N), dan Fosfor (P) pada sedimen berdasarkan kedalaman disetiap stasiun penelitian. Pengambilan sampel dilakukan di 3 titik stasiun yaitu daerah muara sungai, tengah danau, dan hulu danau dengan 3 kali pengulangan. Kandungan karbon (C) pada sedimen di kedalaman 10 cm berkisar antar 1,35 – 1.83%, kedalaman 20 cm berkisar antar 0,73 – 0,78% dan kedalaman 30 cm berkisar antar 0,81 – 1,54%. Kandungan nitrogen (N) berdasarkan kedalaman 10 cm berkisar antar 0,21 – 0,25%, kedalaman 20 cm berkisar antar 0,14 – 0,16% dan kedalaman 30 cm berkisar antar 0,18 – 0,21%. Serta kandungan fosfor (P) berdasarkan kedalaman 10 cm berkisar antar 3,71 – 5,09 mg/l, kedalaman 20 cm berkisar antar 5,15 – 5,39 mg/l dan kedalaman 30 cm berkisar antar 3,37 – 5,15 mg/l di Kawasan Danau Manuk Bungkul Kecamatan Sembakung Kabupaten Nunukan.
Kata Kunci: Karbon, Nitrogen, Fosfor, Sedimen, Danau Manuk Bungkul

The organic matter content of carbon(C), nitrogen(N) and phosphorus (P) in sediments play a role as a process of photosynthesis of respiration and protein formation for plants. The purpose of this study was to find the organic matter content of carbon (C), nitrogen (N) and phosphorus (P) in sediments based on depths of 10 cm , 20 cm, and 30 cm in the area lake Manuk Bungkul Sembakung district Nunukan regency. This research began in September 2019 until January 2020 the method used in this research is quantitative descriptive by describing the carbon content of nitrogen and phosphous in sediments based on depth in each research station. Sampling was carried out at 3 station points namely the river mouth area, the middle of the lake and upstream of the lake with 3 repetitions. Carbon (C) content in sediments at a depth of 10 cm ranger from 1,35 –1,83%, a depth of 20 cm ranged from 0,73 – 0,78% and a depth of 30 cm ranged from 0,81 – 1,54%. Nitrogen (N) content based on 10 cm depth ranged from 0,21 –0,25%, a depth of 20 cm ranged from 0.14 – 0,16% and 30 cm depth ranged from 0,18 – 0,21% and phosphorus (P) content based on a depth of 10 cm ranged from 3,71 mg/l, a depth of 20 cm ranged from 5,15 – 5,39% mg/l and a depth of 30 cm ranged from 3,37 – 5,15 mg/l in the area lake Manuk Bungkul Sembakung district Nunukan regency. Keywords: Carbon, Nitrogen, Phosphorus, Sediments, Lake Manuk Bungkul