Penilaian Kualitas Air Sungai Opak-Oyo di Kabupaten Bantul Periode November-Desember 2025 Berdasarkan Indeks Biotik Famili Makrobentos

Reny Marselinda Putri, Drs. Namastra Probosunu, M.Si.

2026 | Skripsi | MANAJ. SUMBER DAYA PERIKANAN

Sungai Opak-Oyo yang terletak di Kabupaten Bantul memiliki peranan penting bagi masyarakat di sekitarnya. Banyaknya aktivitas antropogenik tersebut berpotensi menimbulkan pencemaran. Salah satu organisme yang paling sensitif terhadap perubahan kondisi perairan sungai yaitu makrobentos. Tujuan penelitian ini adalah untuk mengetahui tingkat pencemaran di Sungai Opak-Oyo berdasarkan Indeks Biotik Famili (IBF) makrobentos. Penelitian ini dilaksanakan pada periode November-Desember 2025. Pengambilan sampel dilakukan setiap satu minggu sekali selama 8 minggu di 5 titik stasiun yang telah ditentukan dengan jumlah ulangan sebanyak 3 kali pada masing–masing stasiun. Sampel air diambil menggunakan botol plastik sedangkan sampel makrobentos diambil menggunakan ekman grab berukuran 14x12 cm. Parameter kualitas air yang diamati meliputi suhu, kedalaman air, kecepatan arus, pH, dissolve oxygen (DO), dan bahan organik. Hasil penelitian menunjukkan bahwa makrobentos di Sungai Opak-Oyo Kabupaten Bantul terdiri dari 9 famili, dan 15 spesies anggota Filum Moluska dan Arthropoda. Famili Thiaridae dan Nerirtidae memiliki jenis paling beragam yaitu sebanyak 4 spesies. Indeks kemelimpahan makrobentos di Sungai Opak-Oyo yaitu 703 individu per meter persegi. Indeks keanekaragaman memiliki nilai 0,81 termasuk dalam kategori sedang. Indeks biotik famili makrobentos memiliki nilai sebesar 6,99 termasuk dalam kriteria buruk. Parameter kualitas air yang diamati meliputi suhu, kedalaman air, kecepatan arus, pH, dissolve oxygen (DO) tidak memiliki korelasi dengan indeks biotik famili makrobentos, sedangkan bahan organik memiliki korelasi dengan indeks biotik makrobentos.

The Opak–Oyo River located in Bantul Regency has an important role for the surrounding community. However, the increasing anthropogenic activities along the river potentially cause water pollution. One of the organisms that is highly sensitive to changes in river water conditions is macrobenthos. This study aimed to determine the pollution level of the Opak–Oyo River based on the Family Biotic Index (FBI) of macrobenthos. The research was conducted during the period of November–December 2025. Sampling was carried out once a week for eight weeks at five predetermined stations, with three replications at each station. Water samples were collected using plastic bottles, while macrobenthos samples were collected using a 14×12 cm ekman grab. The observed water quality parameters included temperature, water depth, current velocity, pH, dissolved oxygen (DO), and organic matter. The results showed that the macrobenthos found in the Opak–Oyo River Bantul Regency, consisted of 9 families and 15 species belonging to the phyla Mollusca and Arthropoda. The families Thiaridae and Neritidae had the highest species diversity, each consisting of four species. The abundance index of macrobenthos in the Opak–Oyo River was 703 individuals per square meter. The diversity index value was 0.81, which was categorized as moderate. The Family Biotic Index (FBI) value was 6.99, indicating poor water quality. The observed water quality parameters, including temperature, water depth, current velocity, pH, and dissolved oxygen (DO), showed no correlation with the Family Biotic Index of macrobenthos, whereas organic matter showed a correlation with the macrozoobenthos biotic index.

Kata Kunci : Kemelimpahan, Keanekaragaman, Indeks Biotik Famili, Makrobentos, Sungai Opak-Oyo