Latar belakang: Sungai merupakan ekosistem perairan yang penting dalam siklus hidrologi, berfungsi sebagai daerah resapan air bagi lingkungannya. Habitat fisik dan kondisi kesehatan perairan sungai sangat dipengaruhi aktivitas antropogenik serta karakteristik lingkungan sekitar. Sungai Bone yang menjadi pusat aktivitas masyarakat di Gorontalo sangat rentan terhadap pencemaran. Makroinvertebrata potensial dijadikan sebagai alat pemantauan pencemaran di sungai karena karakteristik komunitas penyusunnya, yang ditandai dengan perilaku menetap, mobilitas terbatas, dan sensitif terhadap kondisi perairan. Penelitian ini bertujuan untuk menilai kualitas perairan Sungai Bone berdasarkan kondisi habitat fisik dan keanekaragaman makroinvertebrata.Metode: Penilaian terhadap kondisi habitat fisik dan kualitas perairan dilakukan pada 12 stasiun pengamatan yang mewakili aliran utama hulu-hilir Sungai Bone. Penentuan kondisi habitat fisik sungai didasarkan pada pemeriksaan dan penilaian terhadap kriteria tingkat kesehatan habitat sungai dimana parameter yang diamati berupa indikator karakteristik substrat dasar, indikator faktor gangguan, parameter fisika-kimia air. Struktur komunitas makroinvertebrata dianalisis melalui perhitungan keragaman famili makrozoobentos secara keseluruhan, persentase kelimpahan EPT, nilai indeks keanekaragaman (H’), dominasi (D’) serta keseragaman (E’). Penentuan kualitas perairan dilakukan berdasarkan pendekatan Biotilik.Hasil: Hasil penelitian ini mengungkapkan variasi spasial dalam komunitas makroinvertebrata, parameter kualitas air (terutama BOD, COD). Semakin ke hilir kondisi habitat fisik, dan kualitas perairan Sungai Bone cenderung mengalami penurunan.Simpulan: Kualitas perairan Sungai Bone berdasarkan hasil penelitian terbagi menjadi tiga kategori kelompok tercemar yaitu tidak tercemar-sehat (bagian hulu), tercemar ringan-kurang sehat (bagian tengah), dan tercemar ringan-tidak sehat (bagian hilir). Kondisi tercemar di Sungai Bone, terutama di bagian tengah hingga hilir, kemungkinan besar disebabkan oleh pencemaran yang berasal dari aktivitas antropogenik masyarakat. ABSTRACT Title: Physical Habitat Conditions and Macroinvertebrate Diversity as Indicators of Pollution in the Bone River, GorontaloBackground: Rivers are water ecosystems that are important in the hydrological cycle, functioning as water catchment areas for the environment. Anthropogenic activities and the characteristics of the surrounding environment greatly influence the physical habitat and health conditions of river waters. The Bone River, which is the center of community activity in Gorontalo, is very vulnerable to pollution. Macroinvertebrates have the potential to be used as a tool for monitoring pollution in rivers because of the characteristics of their constituent communities, which are characterized by sedentary behavior, limited mobility, and sensitivity to water conditions. This research aims to assess the water quality of the Bone River based on physical habitat conditions and macroinvertebrate diversity.Method: Assessment of physical habitat conditions and water quality was carried out at 12 observation stations representing the main upstream and downstream streams of the Bone River. The evaluation of the river's physical habitat condition was based on the examination and assessment of criteria related to river habitat health, with observed parameters including substrate characteristics, disturbance indicators, and physicochemical water parameters. The structure of the macroinvertebrate community was analyzed by calculating the overall diversity of macrozoobenthos families, the percentage of EPT (Ephemeroptera, Plecoptera, Trichoptera) abundance, and indices of diversity (H’), dominance (D’), and evenness (E’). The water quality assessment was conducted using the Biotilik approach.Result: The results of this study revealed spatial variations in macroinvertebrate communities, water quality parameters (especially BOD, COD). The further downstream the physical habitat conditions, the water quality of the Bone River tends to decline.Conclusion: Based on research results, the water quality of the Bone River is divided into three categories of polluted groups: not polluted-healthy (upstream part), lightly polluted-unhealthy (middle part), and lightly polluted-unhealthy (downstream part). The polluted conditions in the Bone River, especially in the middle to downstream parts, are most likely caused by pollution originating from the community's anthropogenic activities.
