How and why is Aquatic Quality Changing at Nahanni National Park Reserve, nwt, Canada?

Nahanni National Park Reserve is located at southwestern NWT-Yukon border. One of the first UNESCO World Heritage sites, Nahanni lies within Taiga Cordillera and Taiga Shield Ecozones. Base and precious metal mining occurred upstream of Nahanni prior to park establishment. Nahanni waters, sediments, fish, and caribou have naturally elevated metals levels. Baseline water, sediment and fish tissue quality data were collected and analyzed throughout Nahanni during 1988–91 and 1992–97. These two programs characterized how aquatic quality variables are naturally varying in space and time, affected by geology, stream flow, seasonality, and extreme meteorological and geological events. Possible anthropogenic causes of aquatic quality change were examined. Measured values were compared to existing Guidelines and site-specific objectives were established.     

Water Quality Evaluation and Trend Analysis in Selected Watersheds of the Atlantic Region of Canada

Water quality indices (WQIs) have been developed to assess the suitability of water for a variety of uses. These indices reflect the status of water quality in lakes, streams, rivers, and reservoirs. The concept of WQIs is based on a comparison of the concentration of contaminants with the respective environmental standards. The number, frequency, and magnitude by which the environmental standards for specific variables are not met in a given time period are reflected in WQIs. Further, the water quality trend analysis predicts the behavior of the water quality parameters and overall water quality in the time domain. In this paper, the concept of WQI was applied to three selected watersheds of Atlantic region: the Mersey River, the Point Wolfe River, and the Dunk River sites. To have robust study, two different water quality indices are used: Canadian Water Quality Index (CWQI), and British Columbia Water Quality Index (BWQI). The complete study was conducted in two steps. The first step was to organize and process the data into a format compatible with WQI analysis. After processing the input data, the WQI was calculated. The second step outlined in the paper discusses detailed trend analysis using linear and quadratic models for all the three sites. As per the 25 years trend analysis, overall water quality for agriculture use observed an improving trend at all the three sites studied. Water quality for raw water used for drinking (prior to treatment) and aquatic uses has shown improving trend at Point Wolfe River. It is further observed that pH, SO₄, and NO₃ concentrations are improving at Dunk River, Mersey River, and Point Wolfe River sites. To ascertain the reliability and significance of the trend analysis, a detailed error analysis and parametric significance tests were also conducted It was observed that for most of the sites and water uses quadratic trend models were a better fit than the linear models.     

CCME WQI在入海河流(鳌江)感潮河段水质评价中的应用

水质指数(WQI)在环境保护的日常工作中发挥了重要作用。以鳌江为例,运用加拿大环境部长理事会水质指数(CCME WQI)方法,选取pH、溶解氧、高锰酸盐指数、氨氮、总氮、总磷、石油类、氟化物、阴离子表面活性剂、粪大肠菌群10项水质监测项目,评估了入海河流干流感潮河段4个监测断面的地表水环境质量,并对CCME WQI与最差因子法以及CCME WQI优缺点进行比较和分析。研究结果显示,2014年埭头、江屿、方岩渡、江口渡监测断面水质分别为良好、较差、中等、中等。与传统水质评价最差因子法比较,运用CCME WQI评价结果容忍度较高,更贴近实际水质状况。CCME WQI量化形式为属地流域环境管理带来便利。监测断面水质目标和参评项目对CCME WQI评价结果起决定性作用。针对CCME WQI在实际应用中存在的问题给出了建议。     

Application of CCME Water Quality Index to Monitor Water Quality: A Case Study of the Mackenzie River Basin, Canada

All six ecosystem initiatives evolved from many years of federal, provincial, First Nation, local government and community attention to the stresses on sensitive habitats and species, air and water quality, and the consequent threats to community livability. This paper assesses water quality aspect for the ecosystem initiatives and employs newly developed Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) which provides a convenient mean of summarizing complex water quality data that can be easily understood by the public, water distributors, planners, managers and policy makers. The CCME WQI incorporates three elements: Scope – the number of water quality parameters (variables) not meeting water quality objectives (F ₁); Frequency – the number of times the objectives are not met (F ₂); and Amplitude. the extent to which the objectives are not met (F ₃). The index produces a number between 0 (worst) to 100 (best) to reflect the water quality. This study evaluates water quality of the Mackenzie – Great Bear sub-basin by employing two modes of objective functions (threshold values): one based on the CCME water quality guidelines and the other based on site-specific values that were determined by the statistical analysis of the historical data base. Results suggest that the water quality of the Mackenzie-Great Bear sub-basin is impacted by high turbidity and total (mostly particulate) trace metals due to high suspended sediment loads during the open water season. Comments are also provided on water quality and human health issues in the Mackenzie basin based on the findings and the usefulness of CCME water quality guidelines and site specific values.