Nitrogen dalam sedimen merupakan unsur esensial bagi tumbuhan yang berperan dalam proses fotosintesis dan merangsang pertumbuhan. Penelitianaini bertujuan untukamenguji kandunganaNitrogena(N) total padaasedimen berdasarkan perbedaan kedalaman di KawasanaKonservasi Mangroveadan Kepiting KelurahanaPamusian KotaaTarakan. Penelitianadilaksanakan padaabulanaFebruariasampaiadenganaApril 2021. Metode yang digunakan dalam penelitian adalahametode deskriptif kuantitatif denganamendeskripsikan kandungan Nitrogen (N) pada sedimen berdasarkan perbedaan kedalaman di setiap stasiun penelitian dan penentuan lokasi titik sampling untuk pengambilan sampel menggunakan metode purposive sampling. Pengambilan sampel sedimen dilakukan pada 3 titik stasiun yaitu daerah aliran Sungai Pamusian, daerah menara pengawas dan daerah dekat pemukiman penduduk. Pengujian sampel sedimen dilakukan di Laboratorium Tanah Fakultas Pertanian Universitas Borneo Tarakan. Hasil penelitian ini menunjukkan bahwa kandungan Nitrogen (N) pada sedimen di Kawasan Konservasi Mangrove dan Kepiting Kelurahan Pamusian kedalaman 10 cm berkisar 0,25 – 0,32 %, kedalaman 20 cm berkisar 0,19 – 0,24 %, dan kedalaman 30 cm berkisar 0,14 – 0,20 %. Jenis tekstur sedimen yang mendominasi yaitu substrat lempung hingga lempung berpasir.
Kata Kunci: Kedalaman, Mangrove, Nitrogen Total, Pamusian, Sedimen

Nitrogen contained in sediment is an essential element for plants, plays an important role in photosynthesis, and stimulates growth. This research aimed to examine the total nitrogen (N) content in sediment based on the depth differences in the Mangrove and Crab Conservation Area of Pamusian Village, Tarakan. This descriptive-qualitative research was conducted from February to April 2021 by describing the Nitrogen (N) content in sediment based on the depth differences in each research station and determining the sample location points using a purposive sampling technique. The sediment sampling was conducted in 3 station points covering Pamusian River watershed, control tower area, and area in adjacent with the residential areas. The sediment samples were examined at Soil Laboratory, Faculty of Agriculture, Universitas Borneo Tarakan. The research results show that the nitrogen (N) contained in sediment in the Mangrove and Crab Conservation Area of Pamusian Village in the depth of 10 cm, 20 cm, and 30 cm respectively ranged from 0.25 to 0.32%, 0.19 to 0.24%, and 0.14 to 0.20%. The sedimentary texture type was dominated by loam to sandy loam. Keywords: Depth, Mangrove, Total Nitrogen, Pamusian, Sediment