ABSTRACT

The aim of this study was to examine the water quality of the Extrema River spring in a Brazilian Cerrado area. Three collection sites (P1 − P3) were sampled in the dry and rainy seasons, which are close to industries from different sectors. In the physicochemical analysis, a decrease in dissolved oxygen levels (<5 mg/L) and pH (< 6) at P3 was detected. An increase in heterotrophic bacteria count was recorded at all sites (> 500 colonies/ml). In ecotoxicological analyses, P2 and P3 exhibited toxicity using Vibrio fischeri (> 20%). In evaluating toxicity, the reduction in seed germination was significant utilizing Lactuca sativa at all locations and with Allium cepa only at P2; rootlet length was decreased at P3 on L. sativa and at all sites with A. cepa. In contrast, loss of membrane integrity and mitochondrial function of meristems was adversely affected at all locations using both L. sativa and A. cepa assays. Principal components analysis (PCA) approach indicated that seasonality apparently did not markedly interfere with the obtained data, but it is important to include more collection locations to be evaluated with multiple bioindicators in the spring region. Our data indicate the urgent need for more rigorous programs to monitor the discharge of effluents into water springs.

摘要

本研究的目的是检查巴西塞拉多地区埃斯特雷马河泉水的水质。在旱季和雨季对三个收集点（P1-P3）进行了采样，这些收集点靠近不同行业的工业。在理化分析中，检测到 P3 时溶解氧水平 (<5 mg/L) 和 pH (< 6) 下降。所有位点的异养细菌计数均有所增加（> 500 个菌落/ml）。在生态毒理学分析中，P2 和 P3 使用费氏弧菌表现出毒性(> 20%)。在评估毒性时，在所有位置使用莴苣，而仅在 P2 处使用洋葱，种子发芽率显着降低；苜蓿P3 处的细根长度减少，而洋葱 cepa 的所有位点的细根长度均减少。相比之下，使用苜蓿和洋葱检测，分生组织的膜完整性和线粒体功能的丧失在所有位置都受到不利影响。主成分分析（PCA）方法表明，季节性显然没有显着干扰所获得的数据，但重要的是要包括更多收集地点，以利用春季地区的多种生物指标进行评估。我们的数据表明，迫切需要制定更严格的计划来监测排入泉水的废水。