Marziali Laura, Pirola Niccolò, Schiavon Alfredo, Rossaro Bruno
National Research Council-Water Research Institute (CNR-IRSA), Via del Mulino 19, 20861 Brugherio, MB, Italy.
Department of Biology, Chemistry, and Pharmacy, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany.
Insects. 2024 Feb 22;15(3):148. doi: 10.3390/insects15030148.
The Toce River (Northern Italy) is characterized by legacy contamination of dichloro-diphenyl-trichloroethane (DDT), mercury, and arsenic deriving from an industrial plant active between ca. 1915 and 1996. Chironomidae taxa assemblages and sediments were collected in 2014 and 2019 upstream and downstream of the industrial area to analyze species responses to toxic substances in a river stretch with relatively uniform natural (i.e., hydro-morphological) characteristics. A total of 32 chironomid taxa were identified. Sediment concentrations reached levels potentially toxic for benthic invertebrates: 15.7 µg kg 1% organic carbon for DDT, 197 µg kg dry weight (d.w.) for Hg, and 55.7 mg kg d.w. for As. Canonical Correspondence Analysis (CCA) revealed a predominant seasonal gradient, followed by an upstream-downstream gradient. Partial CCA indicated that 5.2% of the total variation was associated with sediment contamination. Self-Organizing Maps (SOMs) were used to represent species responses to toxicants. Most species appeared to be tolerant, e.g., , , , and spp. Sensitivity to contaminants was observed in only a few species: spp., and to DDT; to Hg; and to As. The chironomid community was characterized in presence of contamination levels commonly observed in freshwater ecosystems.
托切河（意大利北部）的特征是受到了来自一家约1915年至1996年间运营的工厂遗留的二氯二苯三氯乙烷（滴滴涕）、汞和砷的污染。2014年和2019年，在工业区上下游采集了摇蚊科分类群组合和沉积物，以分析在一段具有相对统一自然（即水文形态）特征的河段中物种对有毒物质的反应。共鉴定出32个摇蚊科分类群。沉积物浓度达到了对底栖无脊椎动物可能有毒的水平：滴滴涕为15.7微克/千克1%有机碳，汞为197微克/千克干重，砷为55.7毫克/千克干重。典范对应分析（CCA）显示出一个主要的季节梯度，其次是上下游梯度。偏CCA表明，总变异的5.2%与沉积物污染有关。自组织映射（SOM）用于表示物种对有毒物质的反应。大多数物种似乎具有耐受性，例如，[此处列举的物种名称未给出英文原文，无法准确翻译]等物种。仅在少数物种中观察到对污染物的敏感性：[此处列举的物种名称未给出英文原文，无法准确翻译]对滴滴涕敏感；[此处列举物种名称未给出英文原文，无法准确翻译]对汞敏感；[此处列举物种名称未给出英文原文，无法准确翻译]对砷敏感。摇蚊群落的特征是存在淡水生态系统中常见的污染水平。
