Sedimantolojik Proksilere Göre Potansiyel Toksik Element Kaynaklı Ekolojik Risk Seviyesinin Analizi: Gölyazı Litoral Zonu (Uluabat Gölü – Bursa) Örneği / Analysis of Ecological Risk Levels Due to Potential Toxic Elements Based on Sedimentological Proxies: Gölyazı Littoral Zone (Uluabat Lake – Bursa) Example

Öz

Biyoçeşitlilik açısından oldukça önemli olan göl ekosistemlerinde son yıllarda hızla artan antropojenik faaliyetlerin yol açtığı degradasyonel değişimler dikkat çekmektedir. Göl ekosistemlerindeki ortam bozulmasında potansiyel toksik element (PTE) kontaminasyonunun rolü oldukça fazladır. Bu çalışma Türkiye’nin önemli sulak alanlarından biri olan Uluabat (Apolyont) Gölü’nde yer alan ve üzerinde Gölyazı yerleşmesinin yer aldığı tombolo kıyılarındaki ekolojik riske odaklanmıştır. Tombolo kıyısı boyunca göl tabanından alınan sediment örneklerinin organik karbon ve klorofil bozunma ürünleri analizleri yanı sıra ICP-MS ile belirlenen PTE değerlerinden zenginleşme faktörü (EF), kontaminasyon faktörü (CF), modifiye kontaminasyon faktörü (mCD), toksik risk indeksi (TRI), kirlilik yük indeksi (PLI), ekolojik risk indeksi (mER) ve potansiyel ekolojik risk indeksi (PER) hesaplamaları yapılmıştır. Elde edilen verilere göre; göl sedimentlerinde PTE konsantrasyonu açısından Fe (29.200) > Al (21.500) > Mn (962) > Ni (256) > Cr (101) > Zn (90)> As (39) > Pb (37) > Cu (31) > Co (20) şeklinde bir sıralanma söz konusudur. EF verilerine göre PTE’lerin zenginleşme düzeyi Ni (10,31) > As (8,24) > Pb (5.05) > Mn (3,12) > Cr (3,08) > Co (2,81) > Zn (2,58) > Fe (2,30) > Cu (1,88) şeklindedir. PTE kaynaklı ekolojik risk seviyesi Ni (51), Co (41), Pb (25), As (24), Cu (10) olup ortalama potansiyel ekolojik risk seviyesi 161’dir. Gölyazı yerleşmesi çevresindeki litoral zonda Cu hariç diğer tüm PTE’ler belirli miktarda zenginleşmiştir. Göldeki en riskli ekolojik risk kaynağı Ni olarak belirlenmiştir. Orta derecede ekolojik risk tespit edilen göldeki başlıca antropojenik risk kaynakları tarım, endüstri ve yerleşme atıklarıdır.

Anahtar Kelimeler

• Göl ekolojisi
• Ekolojik risk
• Potansiyel toksik element kontaminasyonu
• Sedimantoloji
• Uluabat Gölü
• Limnoloji

Analysis of Ecological Risk Levels Due to Potential Toxic Elements Based on Sedimentological Proxies: Gölyazı Littoral Zone (Uluabat Lake – Bursa) Example

Öz

Degradational changes caused by rapidly increasing anthropogenic activities in recent years in lake ecosystems, which are crucial for biodiversity, have attracted attention. Potentially toxic element (PTE) contamination plays a significant role in environmental degradation in lake ecosystems. This study focused on the ecological risk along the tombolo shores of Lake Uluabat (Apolyont), one of Turkey's important wetlands, where Gölyazı settlement is located. Sediment samples taken from the lake bottom along the tombolo shore were analysed for organic carbon and chlorophyll degradation products. Furthermore, the enrichment factor (EF), contamination factor (CF), modified contamination factor (mCD), toxic risk index (TRI), pollution load index (PLI), ecological risk index (mER), and potential ecological risk index (PER) were calculated using PTE values determined by ICP-MS. Based on the obtained data, the PTE concentration in lake sediments is in the following order: Fe (29200) > Al (21500) > Mn (962) > Ni (256) > Cr (101) > Zn (90)> As (39) > Pb (37) > Cu (31) > Co (20). According to EF data, the enrichment level of PTEs is Ni (10.31) > As (8.24) > Pb (5.05) > Mn (3.12) > Cr (3.08) > Co (2.81) > Zn (2.58) > Fe (2.30) > Cu (1.88). The ecological risk level from PTEs is Ni (51), Co (41), Pb (25), As (24), Cu (10) and the average potential ecological risk level is 161. In the littoral zone around Gölyazı settlement, all PTEs except Cu are enriched to a certain extent. Ni was identified as the ecological risk source with highest risk in the lake. The main anthropogenic risk sources in the lake, where a moderate ecological risk was identified, are agricultural, industrial, and settlement wastes.

Anahtar Kelimeler

• Lake ecology
• Ecological risk
• Potential toxic element contamination
• Sedimentology
• Uluabat Lake
• Limnology

Kaynakça

1. Abrahim, G. & Parker, R. (2008). Assessment of Heavy Metal Enrichment Factors and the Degree of Contamination in Marine Sediments from Tamaki Estuary, Auckland, New Zealand. Environmental Monitoring and Assessment, 136, 227-238. https://doi.org/10.1007/s10661-007-9678-2
2. Arslan, N., Koç, B. & Çiçek, A. (2010). Metal Contents in Water, Sediment, andOligochaeta-Chironomidae of Lake Uluabat,a Ramsar Site of Turkey. The Scientific World Journal, 10, 1269–1281. https://doi.org/10.1100/tsw.2010.117
3. Aykır, D, Fural, Ş., Kükrer, S., Mutlu, Y. E. (2023). Elementbased ecological and human health risk assessment in a lagoon system in a densely populated basin. Oceanological and Hydrobiological Studies, 52(1), 1–19. https://doi.org/10.26881/oahs-2023.1.01
4. Aykol, A., Budakoglu, M., Kumral, M., Gultekin, A. H., Turhan, M., Esenli, V., Yavuz, F. & Örgün, Y. (2003). Heavy metal pollution and acid drainage from the abandoned Balya Pb-Zn sulfide Mine, NW Anatolia. Environmental Geology, 45, 198–208. https://doi.org/10.1007/s00254-003-0866-2
5. Barlas, N., Ahbab, M. A. & Aydoğan, M. (2005). Assessment of Heavy Metal Residues in the Sediment and Water Samples of Uluabat Lake, Turkey. Bulletin of Environmental Contamination and Toxicology, 74, 286-293. https://doi.org/10.1007/s00128-004-0582-y
6. Bowen, H. J. M. (1979). Environmental chemistry of the elements. Academic, London NY-Toronto.
7. Çelenli, A. (2000). Uluabat Gölü Çevre Jeokimyası. [Yayımlanmamış Doktora Tezi]. İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü.
8. Çelik, G. (2000). Çevre Yönetiminde Ekolojik Risk Değerlendirmesi ve Uluabat Ramsar Alanı İçin Problem Formülasyonu [Yayımlanmamış Yüksek Lisans Tezi]. Uludağ Üniversitesi, Fen Bilimleri Enstitüsü.

9. Fural, Ş., Kükrer, S. & Cürebal, İ. (2020). Geographical information systems based ecological risk analysis of metal accumulation in sediments of İkizcetepeler Dam Lake (Turkey). Ecological Indicators, 119, Article 106784. https://doi.org/10.1016/j.ecolind.2020.106784
10. Fural, Ş., Kükrer, S., Cürebal, İ. & Aykır, D. (2021). Spatial distribution, environmental risk assessment, and source identification of potentially toxic metals in Atikhisar dam, Turkey. Environmental Monitoring and Assessment, 193, Article 268. https://doi.org/10.1007/s10661-021-09062-6 PMID:33860380 .
11. Gaudette, H. E., Flight, W. R., Toner, L. & Folger, W. (1974). An inexpensive titration method for the determination of organic carbon in recent sediments. Journal of Sedimentory Petrology, 44, 249–253. https://doi.org/10.1306/74D729D7-2B21-11D7-8648000102C1865D
12. Hacısalihoğlu, S. & Karaer, F. (2004). Ecological Risk Assessment and Problem Formulation for Lake Uluabat, a Ramsar State in Turkey. Environmental Management, 33, 899–910.
13. Hacısalihoğlu, S. & Karaer, F. (2020). Uluabat Gölü Noktasal Kirletici Kaynaklar ve Kirlilik Yükleri. Doğal Afetler ve Çevre Dergisi, 2, 258-267.
14. Hakanson, L. (1980). An Ecological Risk Index for Aquatic Pollution Control: A Sedimentological Approach. Water Research, 14, 975-1001. https://doi.org/10.1016/0043-1354(80)90143-8
15. Hoşgören, M. Y. (1994). Türkiye’nin Gölleri. Türk Coğrafya Dergisi, 29, 19-51.
16. Kandemir, Ö., Pehlivan Ş., Kanar, F.,Tok, T. (2013). 1/100.000 ölçekli Türkiye Jeoloji Haritaları serisi, Bursa-H21 paftası. No:191. Maden Tetkik ve Arama Genel Müdürlüğü, Ankara-Türkiye.
17. Kazancı, N., Leroy, S., İleri, Ö., Emre, Ö., Kibar, M. & Öncel, S. (2004). Late Holocene erosion in NW Anatolia from sediments of Lake Manyas, Lake Ulubat and the southern shelf of the Marmara Sea, Turkey. Catena, 57(3), 277-308. https://doi.org/10.1016/j.catena.2003.11.004
18. Kuşçu, İ. (2024). Uluabat Gölü (Bursa) alansal değişim analizi (1987-2023). Anadolu Orman Araştırmaları Dergisi, 10(2), 87-93.
19. Kükrer, S., Erginal, A. E., Şeker, S. & Karabıyıkoğlu, M. (2015). Distribution and Environmental Risk Evaluation of Heavy Metal in Core Sediments from Lake Çıldır (NE Turkey). Environmental MonitoringnAssessment, 180, Article 453. https://doi.org/10.1007/s10661-015-4685-1
20. Kükrer, S., Çakır, Ç., Kaya, H., & Erginal, A. E. (2019). Historical record of metals in Lake Küçükçekmece and Lake Terkos (Istanbul, Turkey) based on anthropogenic impacts and ecological risk assessment. Environmental Forensics, 20(4), 385–401. https://doi.org/10.1080/15275922.2019.1657985
21. Lorenzen, C. J. (1971). Chlorophyll-degradation products in sediments of Black Sea. Degens, E. T. & Ross, D. A. (Eds.), The Black Sea—Geology, Chemistry, and Biology, (426–428). American Association of Petroleum Geologists, Volume 20. https://doi.org/10.1306/M20377C9
22. Macdonald, D., Carr, R., Calder, F. & Long, E. (1996). Development and Evaluation of Sediment Quality Guidelines for Florida Coastal Waters. Ecotoxicology, 5, 253-278. https://doi.org/10.1007/BF00118995
23. Özmen, H., Kulahcı, F., Cukurovalı, A. & Dogru M. (2004). Concentrations of heavy metal and radioactivity in surface water and sediment of Hazar Lake (Elazığ, Turkey). Chemosphere, 55, 401–408. https://doi.org/10.1016/j.chemosphere.2003.11.003
24. Sanei, H., Outridge, P. M., Oguri, K., Stern, G. A., Thamdrup, B., Wenzhöfer, F., Wang, F., & Glud, R. N. (2021). High mercury accumulation in deep-ocean hadal sediments. Scientific Reports, 11(1), Article 10970. https://doi.org/10.1038/s41598-021-90459-1 PMID:34040077.
25. Sarı, E. (2008) Sources and distribution of heavy metals in river sediments from the southern drainage basin of the sea of Marmara, Turkey. Fresenius Environmental Bulletin, 17, 2007-2019.
26. Sutherland, R. A. (2000). Bed Sediment-Associated Trace Metals in an Urban Stream, Oahu, Hawaii. Environmental Geology, 39, 611- 627. https://doi.org/10.1007/s002540050473
27. Taylor, S. R. & McLennan, S. M. (1995). The geochemical Evolution of the Continental Crust. Reviews of Geophysic, 33(2), 241-265. https://doi.org/10.1029/95RG00262
28. Tekiner, M., Tunçay, T. & Parlak, M. (2025). Environmental and Ecological Risks Posed by Sediment Heavy Metals in Reservoirs: A Preliminary Study from Northwest Türkiye. Journal of Agricultural Sciences, 31(1), 59 – 70. https://doi.org/10.15832/ankutbd.1486524
29. Tomlinson, D. L., Wilson, J. G., Harris, C. R. & Jeffery, D. W. (1980). Problems in the Assessment of Heavy-Metal Levels in Estuaries and the Formation of a Pollution Index. Helgoländer Meeresuntersuchungen, 33, 566-575. https://doi.org/10.1007/BF02414780
30. Turekian, K. & Wedepohl, K. (1961). Distribution of the Elements in Some Major Units of the Earth's Crust. GSA Bulletin, 72, 175-192. https://doi.org/10.1130/0016-7606(1961)72[175:DOTEIS]2.0.CO;2
31. Uludağ, M., Kükrer, S. & Erginal, G. (2018). Anthropogenically-induced ecological risks in Lake Erikli, NW Turkey. International Journal of Environment and Geoinformatics, 5(3), 273-283. https://doi.org/10.30897/ijegeo.459496
32. USEPA, (2007). Method 3051a: Microwave Assisted Acid Dissolution of Sediments, Sludges, Soils, and Oils, Revision 1. United States Environmental Protection Agency, Washington, DC.
33. Ustaoğlu, F., Islam, M. S. & Tokatli, C. (2022). Ecological and probabilistic human health hazard assessment of heavy metals in Sera Lake Nature Park sediments (Trabzon, Turkey). Arabian Journal of Geosciences, 15(7), 1-15. https://doi.org/10.1007/s12517-022-09838-1
34. Walkley, A. & Black, I. (1934). An Examination of the Degthareff Method far Determining Soil Organic Matter and a Proposed Modification of the Chromic Acid Titration Method. Soil Science, 37(1), 29-38. https://doi.org/10.1097/00010694-193401000-00003
35. Wedepohl, K. H. (1979). Handbook of geochemistry. Springer Verlag, Berlin, Heidelberg, NY.
36. Zhang, G., Bai, J., Zhao, Q., Lu, Q., Jia, J. & Wen, X. (2016). Heavy Metals in Wetland Soils Along a Wetland-Forming Chronose Quence in the Yellow River Delta of China: Levels, Sources and Toxic Risks. Ecol Indicator, 69, 331–340. https://doi.org/10.1016/j.ecolind.2016.04.042