Dampak kandungan logam berat terhadap kemunculan polimorfisme ikan badukang (Arius maclatus Fis & Bian) dan Sembilang (Plotosus canius Web & Bia) di Muara Sungai Kahayan serta Katingan, Kalimantan Tengah

Abstract

Studies on the effects of heavy metals on the occurrence of polymorphisms Badukang fish (Arius maculatus Fis & Bian) and Sembilang fish (Plotosus canius Web & Bia) in the estuary of Kahayan and Katingan rivers consist of four stages. The first (1) stage was to study physical, chemical and biological properties. This study aimed to gain an idea of how physical and chemical properties of estuarine waters affect the community structure of biota. The second (2) stage was to study heavy metal content in water environment, biota and bioconcentration factor (BCF). This study aimed to get an idea of how heavy metal content in aquatic environments and the ability of marine biota accumulated heavy metals. The third (3) stage was to study of dispersion patterns of heavy metals accumulated in fish organs and the effects on tissue morphology. This study aimed to obtain a picture of how patterns of body tissue cells of normal and abnormal fish accumulated heavy metals. The forth (4) stage was to study influence the spread of heavy metal accumulation in bone tissue fin hard on the emergence of abnormal morphology (polymorphism). This study aimed to describe how the dispersion pattern of heavy metal accumulation in the bone hard fins had an effect on polymorphism. Results of the first study (1) showed that total suspended solid content in water exceeded the threshold of sea water quality standard (80 mg/l). Sediment of estuarine ware under condition reduced and caused the pH to fall below 7. This did not affect the plankton community structure, but affected macrobenthos community structure (abundance of individuals of the genus). The second study (2) showed that the sea water, sediment, plankton, polychaete and organs of fish contained the highest Pb, followed by Cd and Hg. BCF showed that the plankton and polychaeta accumulated the highest Hg, followed by Pb and Cd, while the organs of fish accumulated the highest Hg, followed by Cd and Pb. The content of heavy metals in sediments and marine biota correlated linearly with the heavy metals contained in the habitat. Sediment accumulated heavy metals at the highest, followed by plankton, fish organs and polychaete. The content of heavy metals in fish organs of small size fish was the highest compared to medium and large size fish. Organ bone hard fin fish contained heavy metals at the highest, followed by kidney, gill, liver and muscle. The third (3) study showed that liver, kidney, gills, muscle fish contained Pb, Hg and Cd complexes. Accumulation of Pb in the body tissue with random patterns clustered. Complex of Hg and Cd accumulation in fish tissue was random dispersion pattern. Accumulation of heavy metals in fish organs caused changes in morphology. The forth (4) study showed that the accumulation of Pb, Hg and Cd clustered in hard fin fish bones allegedly causing polymorphism. This occurred because the accumulation of heavy metals was clustered in the walls of blood vessels and other bone tissues inhibiting the absorption of nutrients, development and growth of bone cells.

Penelitian ini dilakukan di perairan muara Sungai Kahayan dan Katingan, Kalimantan Tengah. Air hujan yang mengalir di atas lokasi pertambangan, bekas kebakaran hutan dan gambut, pengawetan kayu, pertanian, perkebunan, pemukiman menyebabkan pencemaran. Tujuan penelitian ini adalah: (1) Mengaji sifat fisik, kimia perairan dan pengaruhnya terhadap struktur komunitas biota laut di muara Sungai Kahayan serta Katingan. (2) Mengaji kandungan logam berat dalam lingkungan perairan dan biota; kemampuan (bioconcentration factor-BCF) biota laut mengakumulasi logam berat yang terkandung dalam habitat; keter-kaitan kandungan logam berat dalam biota laut dengan yang terkandung dalam habitat. (3) Mengaji pola sebaran akumulasi Hg, Cd dan Pb dalam jaringan organ tubuh ikan serta pengaruhnya terhadap morfologi jaringan organ tubuh ikan Badukang dan Sembilang. (4) Mengaji kandungan dan pola sebaran akumulasi Hg, Cd, Pb yang berpotensi menyebab-kan kemunculan polimorfisme pada tulang sirip keras ikan Badukang dan Sembilang di- muara Sungai Kahayan serta Katingan. Penelitian ini menggunakan metode survei dan pengambilan contoh purposive sampling. Peralatan yang digunakan selama penelitian: Kammerer bottle water sampler, Petersen grab, DO meter, pH meter, Salinometer, Current meter, Deph sounder, Eh meter, plankton net (20 μm), mikroskop, saringan makrobentos, mikrotom, seperangkat alat destruksi dan Atomic Absorption Spectrophotometer (AAS).