Konsentrasi Logam Berat Tembaga (Cu) dan Seng (Zn) serta Bahan Organik pada Sedimen di Perairan Pulau Untung Jawa

Abstract

Sedimen berperan penting sebagai media akumulasi logam berat dalam waktu lama sehingga dapat mencerminkan tingkat pencemaran perairan. Penelitian ini bertujuan menganalisis konsentrasi logam tembaga (Cu) dan seng (Zn), kandungan bahan organik dan ukuran butir sedimen serta menghitung tingkat pencemaran menggunakan Faktor Kontaminasi (CF), Indeks Beban Pencemar (PLI), dan Indeks Geoakumulasi (Igeo). Pengambilan sampel dilakukan di tiga lokasi di perairan Pulau Untung Jawa untuk menganalisis ukuran butir sedimen, kandungan bahan organik, dan konsentrasi logam berat. Konsentrasi logam diukur menggunakan AAS, ukuran butir sedimen dianalisis dengan metode pengayakan kering, sedangkan kandungan bahan organik ditentukan dengan metode LOI. Hasil penelitian menunjukkan sedimen didominasi fraksi pasir. Kandungan bahan organik cenderung homogen. Konsentrasi Cu antara 12,63-23,29 mg/kg dan Zn antara 93,12-133,57 mg/kg. Korelasi antara konsentrasi logam berat Cu dan Zn dengan ukuran butir sedimen menunjukkan korelasi yang lemah hingga kuat. Hubungan yang cukup kuat terlihat antara kandungan bahan organik dengan fraksi halus. Hubungan antara konsentrasi logam berat Cu dan Zn dengan kandungan bahan organik menunjukkan korelasi yang lemah hingga kuat. Nilai Igeo Cu dan Zn mengindikasikan kondisi tidak tercemar, sedangkan nilai CF Zn (0,64-1,46) dan CF Cu (0.28-0.52) menunjukkan kategori tercemar ringan di beberapa titik. Nilai PLI di semua lokasi <1, yang berarti termasuk kategori tidak tercemar.

Sediments are an important medium for the long-term accumulation of heavy metals and can reflect the level of water pollution. This study aims to analyze the concentrations of copper (Cu) and zinc (Zn) metals, organic matter content, and sediment grain size, as well as to calculate pollution levels using the Contamination Factor (CF), Pollutant Load Index (PLI), and Geoaccumulation Index (Igeo). Samples was conducted at three locations in the waters of Untung Jawa Island to analyze sediment grain size, organic matter content, and heavy metal concentration. Metal concentrations were measured using AAS, sediment grain size was analysed using the dry sieving method, and organic matter content was determined using the LOI method. The results showed that the sediment was dominated by sand fractions. The organic material content tends to be homogeneous. Cu concentrations ranged from 12,63 to 23,29 mg/kg and Zn concentrations ranged from 93.12 to 133.57 mg/kg. The correlation between Cu and Zn heavy metal concentrations and sediment grain size showed a weak to strong correlation. A fairly strong relationship was seen between organic matter content and fine fractions. The relationship between the concentrations of heavy metals Cu and Zn and organic matter content showed a weak to strong correlation. Igeo values for Cu and Zn indicated unpolluted conditions, while CF values for Zn (0.64-1.46) and CF values for Cu (0.28-0.52) indicated light pollution at several points. PLI values at all locations were <1, indicating they were in the unpolluted category.