MODEL SEBARAN SPASIAL TEMPORAL KONSENTRASI MERKURI AKIBAT PENAMBANGAN EMAS TRADISIONAL SEBAGAI DASAR MONITORING DAN EVALUASI PENCEMARAN DI EKOSISTEM SUNGAI TULABOLO PROVINSI GORONTALO

Marike Mahmud, Prof. Dr. Sudarmadji, M.Eng.Sc.

2012 | Disertasi | S3 Geografi

Penelitian ini dilaksanakan di aliran Sungai Tulabolo Kabupaten Bone Bolango Provinsi Gorontalo. Penelitian ini bertujuan untuk (1) menentukan sebaran spasial temporal konsentrasi merkuri di air dan sedimen akibat penambangan tradisional ditinjau pada perubahan jarak dan debit air di sungai Tulabolo; (2) menyusun suatu hubungan korelasi kuantitatif jumlah konsentrasi merkuri di dalam air dan sedimen akibat penambangan tradisional berdasarkan faktor-faktor yang mempengaruhinya di Sungai Tulabolo sebagai dasar pengelolaan dan monitoring kualitas air di Kecamatan Suwawa Kabupaten Bone Bolango; (3) Mengkaji dampak penambangan tradisional terhadap ekosistem Sungai Tulabolo yaitu pada air dan sedimen (abiotik), tumbuhan, hewan aquatik dan rambut kepala (biotik) serta hubungan antara konsentrasi merkuri di rambut kepala dan pengaruhnya terhadap kesehatan masyarakat (culture) (4) menyusun strategi pengelolaan lingkungan akibat penambangan tradisional di ekosistem aliran Sungai Tulabolo. Metode yang dipakai dalam penetapan konsentrasi merkuri adalah spekrofotometer serapan atom tanpa nyala. Kriteria pengambilan sampel air dan sedimen adalah tinggi muka air, yaitu muka air tinggi, sedang dan rendah. Pengukuran debit dengan menggunakan metode pelampung. Pengambilan sampel sedimen dengan grab sampler. Pengukuran TSS dengan menggunakan cara Equal Width Increment (EWI). Konsentrasi merkuri di sedimen di ambil pada sedimen dasar dan sedimen melayang. Analisis konsentrasi merkuri di air dan sedimen dilakukan secara spasio-temporal dengan Sistem Informasi Geografis (SIG). Pengaruh konsentrasi merkuri baik pada air, sedimen, tumbuhan, hewan aquatik dan rambut kepala pada ekosistem dianalisis secara deskriftif dengan menggunakan standar baku mutu yang ditetapkan. Pengujian hipotesis tentang pengaruh jarak dan debit terhadap konsentrasi merkuri di air dan sedimen (dasar dan melayang) dilakukan dengan analisis regresi sederhana dan regresi ganda. Hasil penelitian menunjukkan bahwa sampling periode ke I, II, III, IV, V dan VI, semakin jauh jarak semakin menurun konsentrasi merkurinya. Konsentrasi merkuri tertinggi di effluent, cenderung semakin ke hilir semakin kecil. Peninggian di titik tertentu karena gerakan partikel dasar sungai, juga karena adanya kegiatan tambang lain di sekitar. Pengaruh debit terhadap hasil konsentrasi merkuri tidak signifikan karena semakin besar debit semakin besar limbah yang dilepaskan ke lingkungan. Berdasarkan hasil analisis baik pada air, sedimen, tumbuhan, hewan aquatik dan di rambut kepala maka aliran Sungai Tulabolo sudah tercemar oleh merkuri yang diakibatkan oleh penambangan tradisional. Hasil wawancara menunjukkan bahwa keluhan kesehatan bagi masyarakat yang tinggal di tepi aliran Sungai Tulabolo, merupakan gejala awal akibat keracunan merkuri. Hasil analisis konsentrasi merkuri di rambut kepala, 6.67 % berada di atas baku mutu yang ditetapkan, 26,67 % cenderung mendekati baku mutu yang direkomendasikan oleh NCR, dan ini mengindikasikan bahwa masyarakat sudah terkontaminasi merkuri.

The research was conducted in ecosystem Tulabolo River, Bone Bolango Regency, part of Gorontalo Province. The study aims to (1) determine the spatial temporal distribution of mercury concentrations in water and sediment from the traditional mining reviewed the changes in distance and water flow in Tulabolo rivers (2) study the effect of concentration of mercury in water and sediment of affecting factors on the river as the basis for managing and monitoring water quality in the Suwawa sub-district of Bone Bolango Regency, (3) assess the impact of traditional mining on ecosystems of Tulabolo stream and dimensional (abiotic), plants, aquatic animals and human hair (biotic), also relationship between mercury concentrations in human hair and health effects on society (culture), (4) strategize to treat of the environment caused by traditional mining in the ecosystem Tulabolo Rivers. The method used in determining the concentration of mercury is spectrophotometer without a flame atomic absorption. Criteria for sampling water and sediments are the water level in high, medium and low. Measurement of discharge by using a fload methology. Sediment sampling with grab samples. Measurement of TSS by using Equal Width Increment (EWI). The concentration of mercury in the sediment was taken on the basis of sediment and sedimental drift. Analysis of mercury concentration in water and sediment done by spacio-temporal test with Geographic Information Systems (SIG). Effect of mercury concentrations both in water, sediment, plants, animals and aquatic ecosystems, also human hair by descriptive analysis using the specifield quality standard. Testing hypotheses about the influence of fixation distance discharge of mercury concentration in water and sediment (bottom and float) performed by simple regression analysis and multiple regression. The results showed samplings of the I,II, III,IV,V and VI periods (at the mean of water discharge of the river), the highest mercury concentration was found in the effluent, and they tended to weaken the further the sampling spots towards the lower stream. Mercury concentration strengthened at certain spots for particles of the sediments were stirred up, and because of other mining activities around them. Water discharge influence on mercury concentration is not significant because of the higher the water discharge the more would be the waste released into the river. Based on the results of this analysis both in water, sediment, plants, aquatic animals and the human hair of Tulabolo River has been polluted by mercury due to the traditional mining. The interviews reveal that mercury on the communities inhabiting Tulabolo River banks are symptoms of the beginning result mercury poisoning. The results of mercury concentration on scalp hair, 6,67 % of the respondents are above the quality standards threshold and 26,67 % of them tend to approach the quality standards threshold recomemmended by NCR at 12 ppm and it indicate that community have contaminated.

Kata Kunci : Tambang tradisional, Merkuri, Ekosistem Sungai Tulabolo