Dindar Efsun
Department of Environmental Engineering, Faculty of Engineering, Bursa Uludag University, 16059, Bursa, Turkey.
Environ Sci Pollut Res Int. 2025 May;32(24):14860-14890. doi: 10.1007/s11356-025-36560-8. Epub 2025 Jun 2.
Coastal regions, including the Gemlik Gulf in Turkey, face increasing threats from environmental pollution, driven by industrial activities, urban expansion, and wastewater discharges. Despite its ecological and economic significance, limited studies have comprehensively assessed the spatiotemporal variations in seawater quality in this region. This study aims to fill this gap by evaluating the key pollution sources affecting seawater quality in the Gemlik Gulf, particularly following the 2021 Marmara Sea mucilage crisis. The research investigates the distribution of various seawater quality parameters in the Gemlik Gulf (GG), including pH, temperature, density, fluorescence, NH-N, NOx (NO + NO), total N (TN), total P (TP), salinity, chlorophyll-a (Chl-a), and dissolved oxygen (DO). Samples were collected from 31 stations between January 2022 and November 2022, covering the Spring, Summer, Autumn, and Winter seasons. During the investigation, the temperature, salinity, and dissolved oxygen levels of the seawater varied from 10.3-27.3 °C, 23-38.54 psu, and 2.63-10.57 mg L, respectively. The amounts of nitrate + nitrite-N (0.01-3.356 µM), TN (125.72-271.1 µg L), and TP (4.62-28.88 µg L) were measured. Chl-a levels ranged from 0.259 to 6.44 µg L. Surface water quality can be investigated and classified based on contamination levels using the Water Quality Index (WQI) and trophic status. The WQI classed seawater samples as medium water quality. However, the WQI was specifically calculated for surface waters discharging into the sea. The results indicated that Engürücük River (WQI = 78) and Susurluk River (WQI = 77) were classified as "very poor," while Nilüfer River (WQI = 50) and Karsak River (WQI = 57) were categorized as "poor." This situation indicates that the rivers carry significant pollution to the Sea of Marmara. According to the Surface Water Quality Management Regulation, the Gemlik Gulf was classified as hypertrophic-eutrophic in terms of TP and NOx, between January and April varied by location, but was predominantly determined as oligotrophic-mesotrophic. Based on Chl a and trophic index, it was determined that the gulf generally had low water quality-high mesotrophic and poor water quality-eutrophic conditions during winter.
包括土耳其盖姆利克湾在内的沿海地区，正面临着由工业活动、城市扩张和废水排放导致的环境污染带来的日益严重的威胁。尽管该地区具有生态和经济意义，但对其海水质量时空变化进行全面评估的研究却很有限。本研究旨在通过评估影响盖姆利克湾海水质量的主要污染源来填补这一空白，特别是在2021年马尔马拉海黏液危机之后。该研究调查了盖姆利克湾（GG）中各种海水质量参数的分布，包括pH值、温度、密度、荧光、氨氮、氮氧化物（NO + NO）、总氮（TN）、总磷（TP）、盐度、叶绿素a（Chl-a）和溶解氧（DO）。在2022年1月至11月期间，从31个站点采集了样本，涵盖了春、夏、秋、冬四季。调查期间，海水的温度、盐度和溶解氧水平分别在10.3 - 27.3°C、23 - 38.54 psu和2.63 - 10.57 mg/L之间变化。测量了硝酸盐 + 亚硝酸盐氮（0.01 - 3.356 µM）、总氮（125.72 - 271.1 µg/L）和总磷（4.62 - 28.88 µg/L）的含量。叶绿素a水平在0.259至6.44 µg/L之间。可以使用水质指数（WQI）和营养状态根据污染水平对地表水质量进行调查和分类。WQI将海水样本归类为中等水质。然而，WQI是专门针对排入大海的地表水计算的。结果表明，恩居吕库克河（WQI = 78）和苏瑟卢克河（WQI = 77）被归类为“极差”，而尼吕费尔河（WQI = 50）和卡尔萨克河（WQI = 57）被归类为“差”。这种情况表明这些河流将大量污染带入了马尔马拉海。根据地表水质量管理规定，盖姆利克湾在1月至4月期间，就总磷和氮氧化物而言，按位置不同分类为富营养 - 超富营养，但主要被确定为贫营养 - 中营养。根据叶绿素a和营养指数，确定该海湾在冬季总体上具有低水质 - 高营养和差水质 - 富营养的状况。
