Instituto de Ciencias de La Tierra, Biodiversidad y Ambiente (ICBIA), UNRC-CONICET, Argentina; Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N 36 e Km 601, CP 5800 Río Cuarto, Argentina.
Instituto de Ciencias de La Tierra, Biodiversidad y Ambiente (ICBIA), UNRC-CONICET, Argentina; Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N 36 e Km 601, CP 5800 Río Cuarto, Argentina.
Sci Total Environ. 2023 Dec 15;904:166936. doi: 10.1016/j.scitotenv.2023.166936. Epub 2023 Sep 9.
Fluorite mining activities have been scarcely evaluated so far and the potential effect of this activity on larval stages is poorly known. Thus, studies addressing the effect of contaminants present in water bodies on the health of amphibian larvae are crucial information for their conservation and constitute a warning sign of environmental modification. This study aims to evaluate the effects of natural and artificial surface waters associated with a fluorite mine on the early life stages of Rhinella arenarum. Using microcosms, we assessed four sites with different degrees of disturbance by the fluorine mine: Vallecitos stream (undisturbed); Cerros Negros upstream of mining camp (low disturbance); Cerros Negro downstream of mining camp (medium disturbance); Decantation Ponds (high disturbance). For 65 days we measured different endpoints at different periods of tadpole development. The highest mortality of tadpoles was observed in the Decantation Ponds. In the same way, larval body condition was lower at Decantation Ponds throughout the study, due mainly to the lower weight. A significant decrease in growth and development was observed in Cerros Negro downstream of the mining camp and Decantation Ponds. No significant differences in growth, development and mortality were observed for the other two sites. At the metamorphic climax we observe a lower body condition and a reduced recruitment of individuals in Decantation Ponds. This study allowed us to assess the effect on larvae of R. arenarum of fluorite mining wastewater compared with other near-natural sites. Given the potentially negative synergic effects of mixed water pollutants on tadpoles, this study suggests that chronic exposure to fluorite mining water may significantly impact the adult amphibian population structure, thus altering population viability. Therefore, we propose to monitor the correct functioning of the mine and especially of Decantation Ponds to avoid discharges into the natural streams.
萤石矿开采活动迄今尚未得到充分评估，其对幼虫阶段的潜在影响知之甚少。因此，研究污染物对水体中两栖类幼虫健康的影响，对于它们的保护至关重要，也是环境变化的警示信号。本研究旨在评估与萤石矿相关的天然和人工地表水对 Rhinella arenarum 早期生命阶段的影响。我们使用微宇宙，评估了受萤石矿干扰程度不同的四个地点：Vallecitos 溪流（未受干扰）；采矿营地上游的 Cerros Negros（低干扰）；采矿营地下游的 Cerros Negro（中干扰）；沉淀池（高干扰）。在 65 天的时间里，我们在不同的时间点测量了不同发育阶段的蝌蚪的不同终点。在沉淀池，蝌蚪的死亡率最高。同样，在整个研究过程中，沉淀池的幼虫身体状况也较差，主要是体重较低。在采矿营地下游的 Cerros Negro 和沉淀池观察到生长和发育显著下降。其他两个地点的生长、发育和死亡率没有显著差异。在变态高峰期，我们观察到沉淀池的个体身体状况较差，且招募的个体较少。本研究使我们能够评估萤石矿废水对 R. arenarum 幼虫的影响，并与其他近自然地点进行比较。鉴于混合水污染物对蝌蚪可能产生潜在的负面协同效应，本研究表明，慢性暴露于萤石矿水中可能会对成年两栖类动物种群结构产生重大影响，从而改变种群的生存能力。因此，我们建议监测矿山特别是沉淀池的正常运行，以避免向自然溪流排放。
