ABSTRACT:The impact of petrochemical special economic zone activities on the health status of Jafari Creek was studied by assessing the changes in macroinvertebrate assemblages in nine sites during September 2006-January 2008. The relationship between spatial pattern of macroinvertebrate assemblages and ambient factors (i.e. water temperature, salinity, pH, dissolved oxygen, sediment grain size distribution, sediment organic content, heavy metals contents) was measured. Background enrichment indices, contamination factor and contamination degree, were used to assess the health status in the study area based on nickel, lead, cadmium and mercury contents of the sediments. The macrobenthic communities had a low diversity and were dominated by opportunistic taxa. The BIO-ENV analysis identified salinity, dissolved oxygen, pH and silt/clay content of sediments as the major environmental variables influencing the infaunal pattern. This suggests that management should attempt to ensure minimal disturbance to environmental variables underlying the spatial variation in macroinvertebrate assemblages. Background enrichment indices showed that the health of Jafari Creek has declined over time due to the constant discharge of heavy metals to the Creek system. These indices also identified a significant degree of pollution in the study area. The decrease in the ecological potential of Jafari Creek was best highlighted by the alteration in macrobenthic assemblages.
Telah disintesis komposit zero valent iron (ZVI)-carboxymethyl cellulose (CMC) yang digunakan untuk reduksi dan adsorpsi pada logam berat Cu2+. Penelitian ini bertujuan untuk mengetahui karakterisasi komposit yang terbentuk antara CMC dengan partikel besi dan karakter proses remediasi logam Cu2+. Sintesis komposit ZVI-CMC tanpa menggunakan atmosfer N2 dengan perbandingan konsentrasi Fe2+/BH4- sebesar 1:3, variasi konsentrasi CMC sebesar 0,1, 0,2 dan 0,3w/v%, pH 6 dan suhu sintesis dan 220C. Karakterisasi FT-IR menunjukkan kestabilan ikatan antara CMC dengan partikel besi pada variasi CMC sebesar 0,2w/v% dengan pergeseran bilangan gelombang dari gugus –OH CMC sebesar 3425,58 cm-1 menjadi 3302,13 cm-1 untuk sampel tanpa pengeringan, kemudian karakterisasi XRD menunjukkan bahwa partikel ZVI (Fe0) yang terbentuk dari proses sampel tanpa pengeringan dan sampel kering memiliki karakter kristalinitas yang rendah pada puncak secara berurutan sebesar 2θ: 65,10 dan 44,90 serta terbentuknya senyawa oksida besi dan senyawa lain. TEM menginformasikan bahwa ukuran dari ZVI serta senyawa magnetik (atau oksida besi) serta pengukuran kristalisasi ZVI maupun senyawa magnetik (atau oksida besi) berada dalam ukuran < 2 nanometer. Aplikasi komposit ZVI-CMC ini dilakukan pada titik optimum pH 4, waktu kontak sebesar 6 jam dan massa komposit ZVI-CMC sebesar 0,35 gram. Hasil reduksi dan adsorpsi larutan Cu2+ mengalami deaktivasi yang ditunjukkan oleh dua puncak pada 2θ: 44,70 dan 65,10 disertai dengan penurunan kristalinitas senyawa magnetik atau senyawa oksida besi.
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