Evaluation of Ecological Risk Based on the Sediment and Water Quality in Klang Strait, Malaysia
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EVALUATION OF ECOLOGICAL RISK BASED ON THE SEDIMENT AND WATER QUALITY IN KLANG STRAIT, MALAYSIA SEYEDEH BELIN TAVAKOLY SANY THESIS SUBMITTED IN FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY INSTITUTE OF BIOLOGICAL SCIENCE FACULTY OF SCIENCE UNIVERSITY OF MALAYA KUALA LUMPUR 2012 UNIVERSITI MALAYA ORIGINAL LITERARY WORK DECLARATION Name of Candidate: SEYEDEH BELIN TAVAKOLY SANY I.C/Passport No: I12182331 Registration/Matric No: SHC080071 Name of Degree: DOCTOR OF PHILOSOPHY Title of Project Paper/Research Report/Dissertation/Thesis (“this Work”): EVALUATION OF ECOLOGICAL RISK BASED ON THE SEDIMENT AND WATER QUALITY IN KLANG STRAIT, MALAYSIA Field of Study: ENVIRONMENT I do solemnly and sincerely declare that: (1) I am the sole author/writer of this Work; (2) This Work is original; (3) Any use of any work in which copyright exists was done by way of fair dealing and for permitted purposes and any excerpt or extract from, or reference to or reproduction of any copyright work has been disclosed expressly and sufficiently and the title of the Work and its authorship have been acknowledged in this Work; (4) I do not have any actual knowledge nor do I ought reasonably to know that the making of this work constitutes an infringement of any copyright work; (5) I hereby assign all and every rights in the copyright to this Work to the University of Malaya (“UM”), who henceforth shall be owner of the copyright in this Work and that any reproduction or use in any form or by any means whatsoever is prohibited without the written consent of UM having been first had and obtained; (6) I am fully aware that if in the course of making this Work I have infringed any copyright whether intentionally or otherwise, I may be subject to legal action or any other action as may be determined by UM. Candidate’s Signature Date Subscribed and solemnly declared befor, Date Witness’s Signature Name: Designatio: ABSTRACT Sediment and water monitoring was performed from Nov. 2009 to Oct. 2010 to assess and evaluate the spatial and temporal distribution of physical and chemical parameters and biological variables such as PAHs, trace metals (Hg, Cd, Pb, Cu, Mn, Zn, Cr, Ni, V, and Fe), the structure of the benthic community in the sediment, nutrients and chlorophyll a in the water. Sediment and water samples were collected from 22 stations, which covered three coastal ports (North Port, West Port and South Port) and a control point. The primary objectives of this study were to evaluate the sources of pollutants and each pollutant’s distribution, concentration and contamination degree, as well as to assess the biological response to these stressors based on the ecological risk. Significant variations were found in the distribution and concentrations of all heavy metals and PAHs. The spatial and temporal scales of these variations were related to the several sources contributing to the contamination load in the Klang Strait and to seasonal fluctuations, respectively. The highest concentrations of all metals (except for Mn) were recorded at South Port at stations 16 and 17 parallel to the mouth of the Klang River and at station 13 around the container terminal in the West Port, whereas the lowest concentrations were recorded at the control point. Enrichment factor (EF) index also indicated that all metal concentrations except for Fe were influenced by anthropogenic effects. Similarly, the total organic carbon and fine particle size had significant correlations with most metals (Al, Cd, Cu, Fe, Ni, V and Zn). Thus, both natural processes and human activities contributed to the load of these pollutions in the Klang Strait. The PCA analysis is concordant with the pair isomer ratio of PAHs, which revealed that the anthropogenic sources of PAHs were a mixture of pyrogenic and petrogenic sources at all stations except for stations 4, 14 and 21, where combustion was the more frequent cause. Source analysis revealed that PAHs are primarily derived i from liquid fossil fuels related to the use of vehicles, crude oil and coal (petroleum combustion sources), and a minor amount of PAHs may be related to the direct discharge of petroleum and land-based runoff. Results revealed that most of the sediment samples are in a pristine state with respect to PAHs and metal contamination except for Cd, As, Hg and Pb. Surface sediment in the Klang Strait are moderately polluted by Hg, Pb and As, and only Cd was estimated to have a high level of contamination. Furthermore, risk analysis showed that living organisms in the strait have a high risk of Cd and Hg exposure and only a low risk of overexposure to the rest of the investigated metals and PAHs at all stations. Regarding the risk index classification, only sediments from stations 16 and 17 (mouth of the Klang River) can be considered to represent a high ecological risk. Other stations were categorized as representing slight to moderate risk, and adverse effects were rarely recorded at the control station, which usually showed normal responses. In addition, the level of response of benthic communities to pollutants in the sediment was completely homogeneous with the risk level in most of the stations. In the case of water-quality assessment, multi-metric indices and operational indicator have been proposed to classify trophic level at different sites. The trophic level of Klang Strait coastal water ranges from eutrophic to hypertrophic. Chl-a concentration was used to estimate the biological response of phytoplankton biomass and indicated eutrophic conditions in the Klang Strait and mesotrophic conditions at the control site. During the study period, no harmful algal bloom (secondary symptom) occurred, which may be related to hydrodynamic turbulence and water exchange, which prevent the development of eutrophic conditions in the Klang Strait. Keywords: Ecological risk, Heavy metal, Polyaromatic hydrocarbons (PAHs), Nutrients, Benthic organisms, Chlorophill a, Klang Strait, Malaysia ii ABSTRAK Dalam kajian ini, pemantauan mendapan dan air dilakukan dari Nov. 2009 ke Okt. 2010 bagi mengukur kualiti air dan kualiti mendapan dan meniliai taburan ruang dan masa bagi pemboleh ubah fisikokimia dan biologikal seperti PAH, logam berat (Hg, Cd, Pb, Cu, Mn, Zn, Cr, Ni, V, dan Fe), struktur komuniti bentik dalam mendapan, nutrien dan chlorophyll a dalam air. Sampel air dan mendapan dikumpul daripada 22 stesen, yang merangkumi tiga pelabuhan (Pelabuhan Selatan, Pelabuhan Utara dan Pelabuhan Barat) dan satu tapak kawalan.Tijuana utama penyelidikan ini adalah untuk menilai punca pelbagai jenis pencemaran dan taburan setiap pencemar, kepekatannya dan tahap pencemarannya dan juga untuk mengukur respons biological kepada tekanan- tekanan ini.Terdapat variasi signifikan dalam taburan dan kepekatan semua logam berat dan PAH.Skala spatial dan temporal variasi tersebut berkaitan dengan kepelbagaian punca yang menyumbang kepada beban pencemaran dalam Selat Kelang dan turun-naik bermusim, masing-masing. Kepekatan tertinggi semua logam (melainkan Mn) dirakamkan di Pelabuhan Selatan di Stesen 16 dan 17 selari dengan muara Sungai Klang dan di stesen 13 di sekitar terminal kontena di Pelabuhan Barat, manakala kepekatan paling rendah dirakamkan di kawasan kawalan. Anggaran factor pengkayaan (EF) juga menunjukkan bahawa kepekatan semua logam melainkan Fe dipengaruhioleh kesan antropogenik.Begitu juga, jumlah karbon organik dan saiz partikel halus mempunyai korelasi signifikan dengan kebanyakan logam (Al, Cd, Cu, Fe, Ni, V dan Zn). Oleh itu kedua-dua proses semula jadi atau mineralogi dan aktiviti manusia (kesan antropogenik) menyumbang kepada beban pencemar tersebut dalam Selat Kelang. Analisis PCA menyamai pair isomer ratio PAH, yang menunjukkan punca antropogenetik PAH adalah gabungan punca pyrogenik dan petrogenik di semua stesen kecuali stesen 4, 14 dan 21, iii di mana pembakaran menjadi punca yang paling kerap. Analisis punca menunjukkan bahawa PAH kebanyakannya berasal dari bahan api fosil cecair dan berkaitan dengan penggunaan kenderaaan, minyak mentah dan batu arang (berpunca dari pembakaran petroliam); ada sedikit amaun PAH yang mungkin berkaitan dengan pelepasan langsung petroliam dan land-based runoff. Dapatan kajian menunjukkan bahawa kebanyakan sampel mendapan adalah dalam keadaan asal dari segi PAH dan pencemaran logam melainkan Cd, As, Hg dan Pb. Mendapan permukaan dalam Selat Kelang dicemar secara sederhana oleh Hg, Pb dan As, dan hanya Cd dijangka menunjukkan pencemaran yang tinggi. Tambahan pula, analisis risiko menunjukkan bahawa organisme hidup dalam selat itu mempunyai risiko tinggi untuk pendedahan kepada Cd and Hg dan hanya risiko rendah pendedahan lebihan kepada logam lain yang dikaji dan PAH di semua stesen.Merujuk kepada klasifikasi indeks risiko, hanya mendapan dari stesen 16 dan 17 (muara Sungai Kelang) boleh dikira sebagai menghadapi risiko ekologikal yang tinggi. Stesen yang terancam dan stesen lain dikategorikan sebagai berisiko rendah sehingga sederhana, dan kesan buruk amat jarang dirakamkan di stesen kawalan, yang mana kebiasaannya menunjukkan respons normal. Selain itu, tahap respons komuniti bentik kepada pencemar dalam mendapan adalah bersinkronisasi dengan tahap risiko di kebanyakan stesen. Dalam penilaian kualiti air, indeks multi-metric dan operasional telah dicadangkan untuk mengklasifikasi status trophic di kawasan berlainan.Tahap trophic air Selat Kelang (Pelabuhan Selatan, Pelabuhan Utara dan Pelabuhan Barat) merangkumi keadaan eutrophic sehingga hypertrophic.Kepadatan Chl-a digunakan untuk