Department of Biology, Faculty of Arts and Science, Gaziantep University, 27310, Gaziantep, Turkey.
Environ Sci Pollut Res Int. 2020 Aug;27(22):27796-27806. doi: 10.1007/s11356-020-09140-1. Epub 2020 May 12.
Bio-evaluating of surface waters is not a new approach but is becoming more important since the application of the European Water Framework Directive (WFD). The present study was designed to evaluate the limno-ecological conditions of rivers in the West Mediterranean basin of Turkey using diatom metrics and multivariate approaches according to the WFD requirements. Canonical correspondence analysis (CCA) was used to assess the relationships of diatom species and environmental variables from 17 stations of 12 rivers sampled in two seasons. The CCA indicated that nitrite, chloride, electrical conductivity (EC), sulfate, temperature, and total phosphorus (TP) are the most explanatory factors on the distribution of the diatom species. Karasu River had the most deteriorated ecosystem, distinctly revealed by the CCA. Nutrient enrichment and high EC, biological oxygen demand (BOD), and temperature values were noticed in this ecosystem. Karasu River was also characterized by pollution tolerant diatom species (e.g., Nitzschia inconspicua, Nitzschia pusilla, Halamphora normanii, and Rhoicosphenia abbreviata). Trophic index Turkey (TIT), eutrophication and/or pollution index-diatom (EPI-D), and trophic index (TI) showed poor ecological conditions in Karasu and Hamzabey rivers when a moderate environment quality in Dalaman River (at R6 station) and a good ecological state in Kocadere River. A high ecological status was found in Dalaman (at R5 station) concerning the results of TIT and TI, while a good condition was recorded based on EPI-D. This ecosystem was also associated with pollution-sensitive diatom taxa (Achnanthidium minutissimum, Cymbella excisa, Meridion circulare, and Gomphonema olivaceum). Results of CCA were corroborated with the bio-assessment of sampling stations based on diatom metrics. TIT, TI, and EPI-D had different indices' scores, but they showed significantly positive correlations with logTP. Spearman correlation coefficient value of TIT strengthens the suitability of it for the bio-assessment of the rivers in the West Mediterranean basin of Turkey.
生物评估地表水并不是一种新方法，但随着欧洲水框架指令 (WFD) 的应用，它变得越来越重要。本研究旨在根据 WFD 的要求，使用硅藻指标和多元方法评估土耳其西地中海盆地河流的湖沼生态条件。利用典范对应分析 (CCA) 评估了在两个季节从 12 条河流的 17 个采样点采集的硅藻物种和环境变量之间的关系。CCA 表明，亚硝酸盐、氯化物、电导率 (EC)、硫酸盐、温度和总磷 (TP) 是影响硅藻物种分布的最具解释性因素。卡鲁苏河的生态系统明显恶化，这一点在 CCA 中得到了清晰的揭示。该生态系统中注意到了营养物质富化和高 EC、生物需氧量 (BOD) 和温度值。卡鲁苏河还以耐污染的硅藻物种为特征（例如，Nitzschia inconspicua、Nitzschia pusilla、Halamphora normanii 和 Rhoicosphenia abbreviata）。在卡鲁苏河和哈姆扎贝伊河，当达勒曼河（R6 站）的环境质量适中且科恰代雷河的生态状况良好时，土耳其营养指数（TIT）、富营养化和/或硅藻污染指数（EPI-D）以及营养指数（TI）显示出较差的生态条件。基于 TIT 和 TI 的结果，达勒曼河（R5 站）的生态状况较高，而基于 EPI-D 的结果记录了较好的状况。该生态系统还与污染敏感的硅藻分类群（Achnanthidium minutissimum、Cymbella excisa、Meridion circulare 和 Gomphonema olivaceum）有关。CCA 的结果与基于硅藻指标的采样点生物评估结果相符。TIT、TI 和 EPI-D 具有不同的指数得分，但它们与 logTP 呈显著正相关。TIT 的斯皮尔曼相关系数值增强了它用于评估土耳其西地中海盆地河流的适用性。
