Water contamination is a major environmental problem in many cities of the world. Most water contamination results from industry and human activities that generate toxic substances (e.g., metals). Rheophilic and aquatic mosses are found in lotic ecosystems, and their morphological and physiological traits are responsive to ecological and pollution gradients. Here we hypothesized that the native rheophilic moss Platyhypnidium aquaticum (A. Jaeger) M. Fleisch exposed to polluted waters can bioaccumulate greater amounts of metals, and a metalloid, than P. aquaticum exposed to pollution-free water. To this aim, we tested the bioindicator capacity of the aquatic P. aquaticum for 15 metals (Cd, Pb, Zn, Fe, K, Ca, Na, Mn, V, Co, Ba, Cr, Al, Sr, and Mg) and one metalloid (As), in twelve river samples coming from three urban and one control zone along the Zamora river in the city of Loja. When compared to the control, our results showed that P. aquaticum in the Southern, Central, and Northern zones of the city bioaccumulated higher concentrations of Ba, Cd, Co, Fe, Mg, Mn, Na, Sr, Zn, and the metalloid As. On the other hand, concentrations of Al, Ca, Cr, Pb, and V in P. aquaticum tended to be lower in the control zone, but these differences were not significant. We suggest that the presence of these contaminants may be related to water pollution (e.g., residual discharges and a lack of treatment systems) along urban zones of the river. We report for the first time the utility of P. aquaticum as a model species for development of long-term biomonitoring programs of water contamination in South America. Passive biomonitoring with P. aquaticum can be a simple and low-cost method to obtain reliable data of the current state of water contamination with metals and metalloids in tropical regions.

中文翻译：

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桔梗作为新热带山区城市河流水金属和准金属污染的生物指示剂。

在世界许多城市，水污染是一个主要的环境问题。大多数水污染源于工业和人类活动，这些活动产生有毒物质（例如，金属）。在抽水生态系统中发现了亲液和水生苔藓，它们的形态和生理特征对生态和污染梯度具有响应。在这里，我们假设暴露于污染水的天然嗜水藓类水生侧柏（A. Jaeger）M. Fleisch比暴露于无公害水的水生疟原虫能累积更多的金属和类金属。为此，我们测试了水生体育假单胞菌的生物指标能力。在来自三个城市的十二个河流样本中，用于15种金属（镉，铅，锌，铁，钾，钙，钠，锰，钒，钴，钡，铬，铝，锶和镁）和一种准金属（砷）以及洛哈市Zamora河沿岸的一个控制区。与对照相比，我们的研究结果表明，该市南部，中部和北部地区的水生生物累积了较高浓度的Ba，Cd，Co，Fe，Mg，Mn，Na，Sr，Zn和准金属如。另一方面，水生假单胞菌中Al，Ca，Cr，Pb和V的浓度在控制区趋向于较低，但这些差异并不明显。我们建议这些污染物的存在可能与沿河市区的水污染（例如，残留的排放物和缺乏处理系统）有关。我们首次报告了南美白对虾作为开发长期水污染生物监测程序的典范物种的实用性。水生毕赤酵母的被动生物监测可以是一种简单且低成本的方法，可以获取热带地区金属和准金属对水污染现状的可靠数据。