Analisis Kualitas Fisiko Kimia dan Kadar Logam Berat pada Ikan Mas (Cyprinus carpio L.) dan Ikan Nila (Oreochromis niloticus L.) di Perairan Kaligarang Semarang

Tujuan penelitian untuk mengetahui kualitas fisiko kimia air sungai Kaligarang dan kandungan logam berat pada ikan mas dan ikan nila yang hidup di sungai tersebut. Penelitian ini merupakan penelitian eksperimen lapangan, menggunakan Karamba Jaring Apung. Parameter fisiko-kimia yang diukur adalah suhu, pH, DO, alkalinitas, kesadahan, kecerahan dan kecepatan arus serta kandungan logam berat di air sungai, menggunakan metode Atomic Absorption Spectrophotometry (AAS). Kadar logam berat Cd, Pb dan Hg juga dianalisis pada ikan mas dan ikan nila Hasil penelitian menunjukkan bahwa suhu, pH, DO, alkalinitas, kesadahan, kecerahan dan kecepatan arus masih berada dalam kisaran yang layak bagi kehidupan ikan. Kadar Cd, Pb dan Hg di perairan masing-masing adalah sebesar 0,006 mg/L, 0,01 mg/L dan 0,0006 mg/L. Kadar Cd, Pb dan Hg pada hati ikan nila berturut-turut 0,000407 mg/kg, 0,000812 mg/kg dan 0,000575 mg/kg, sedangkan pada ikan mas 0,000307 mg/kg, 0,000269 mg/kg dan 0,000349 mg/kg. Kesimpulan; air sungai Kaligarang terkontaminasi logam berat Cd, Pb dan Hg dan ikan yang hidup di sungai tersebut telah mengakumulasikan ketiga logam berat tadi. The aim of this study is to determine the quality of water in Kaligarang based on the physicochemical characteristics and heavy metal content in carp and tilapia fish live in the river. This study is a field experiment, by using Karamba floating net; the fish were caught and maintained. The physicochemical parameters of the water measured were temperature, pH, oxygen, alkalinity, hardness and brightness, speed of the flow and content of heavy metals. The heavy metal content was measured using Atomic Absorption Spectrophotometry (AAS). Levels of heavy metals (Cd, Pb and Hg) were also analyzed in carp and tilapia. The results showed that temperature, pH, oxygen, alkalinity, hardness, brightness and speed of the flow were still within the appropriate range for the life of the fish. Levels of Cd, Pb and Hg in water were amounted to 0.006 mg/L, 0.01 mg/L and 0.0006 mg/L, respectively. Surprisingly, the levels of Cd, Pb and Hg in liver of tilapia were 0.000407 mg/kg, 0.000812 mg/kg and 0.000575 mg/kg, respectively, whereas in carp were 0.000307 mg/kg, 0.000269 mg/kg and 0.000349 mg/kg, respectively. It can be concluded that, Kaligarang River was contaminated with heavy metals Cd, Pb and Hg. This contamination leads to the accumulation of heavy metals in fish that live in the river.