Makrozoobentos adalah hewan yang dapat dijadikan bioindikator kualitas perairan karena perubahan populasinya dipengaruhi faktor lingkungan. Penelitian ini dilakukan di Daerah Aliran Sungai Karang Anyar Pantai Kota Tarakan karena wilayah tersebut diduga terdapat sumber bahan pencemar dengan kondisi lingkunga yang bervariasi. Tujuan penelitian ini untuk mengetahui hubungan fisika kimia perairan DAS Karang Anyar Pantai dengan indeks keanekaragaman (H’) makrozobentos sebagai bioindikator. Pengambilan sampel dengan purposive sampling. Perhitungan indeks keanekaragaman (H’), keseragaman (E), dan domnansi (D) dengan rumus Shannon-Wienner. Variabel yang diukur meliputi fisika (suhu, kecerahan, kecepatan arus, dan kekeruhan) dan kimia (pH dan DO). Analisis hubungan antara indeks keanekaragaman dengan variabel fisika kimia menggunakan rumus Pearson. Hasil penelitian menunjukkan kelimpahan makrozoobentos berkisar antara 2045-4129 ind/m. Nilai indeks keanekaragaman (H’) makrozoobentos berkisar antara 0,19-0,24. Hasil analisis korelasi Pearson yaitu faktor suhu, pH, dan DO sangat kuat (0,80-1,00). Korelasi Pearson suhu dan pH berlawan, sedangkan DO searah terhadap keanekaragaman makrozoobentos. Pengaruh kecerahan dan kecepatan arus terhadap keanekaragaman makrozoobentos sedang (0,40-0,559) dengan korelasi berlawanan. Korelasi antara kekeruhan dengan indeks keanekaragaman (H’) -0,150 memiliki tingkat korelasi sangat rendah (0,000,199) arah korelasi berlawanan.
Kata Kunci: Makrozoobentos, Kenekaragaman, DAS Karang Anyar Pantai

Macrozoobentos are organism that can be used as bioindicators of water quality because of their population changes influenced by environmental factors. The research was conducted is done in the coastal flow area of Karang Anyar Pantai Tarakan City, because the area is suspected to be a source of pollutants with varying environment conditions. The purpose of research is to know the physical chemistry of the water-chemical physics area of Karang Anyar Pantai with the index diversity (H ') Makrozobentos as bioindicators. Sampling with purposive sampling. Calculation of diversity index (H'), uniformity (E), and Dominancy (D) with the formula Shannon-Wienner. The variables measured include physics (temperature, brightness, current velocity, and turbidity) and chemistry (pH and DO). Analysis of the link between the diversity index and the chemical physics variables using Pearson formula. The results showed an abundance of macrozoobentos ranging from 2045-4129 ind/m. The value of the Diversity index (H ') of Macrozoobentos ranges from 0.19 to 0.24. The results of Pearson's correlation analysis are temperature factor, pH, and DO very strong (0,80-1.00). The Pearson correlation temperature and pH opponent, while the DO in direct to the diversity of Macrozoobentos. The influence of brightness and velocity of current to the diversity of Macrozoobentos (0.40-0,559) with opposite correlation. The correlation between turbidity and diversity index (H ')-0.150 has a very low correlation rate (0.00-0,199) direction of opposite correlation. Keywords: Macrozoobentos, diversity, and DAS Karang Anyar Pantai