WATER QUALITY AND LAKE WINNIPEG WATERSHED MANAGEMENT
Description
It is suggested that the answers can be provided in a maximum of 6 pages, but no deductions will be made if you exceed this length within reason. You MUST include in-text citations and a reference list at the end of your assignment. You can use paragraphs/full sentences or point form to answer each question.
Remember that the assignment is worth a significant value (20% toward your course total) and therefore you will be evaluated on the completeness of your answers. You should therefore spend time to ensure that you have provided a complete and robust answer to each question, and include at least 5 references based on your own independent research. (Note that the textbook, recommended websites listed in the assignment, and on-line class notes do not contribute to these 5 references). Note also that scientific style in writing does not include quotations. You must summarize technical information in your own words.
Part A. Water Pollution and Water Quality Assessment (20 marks)
Review the concepts of water quality using your course notes in Unit 6, and watch the Nature of Things production Save my Lake
Based on this information and your own independent research, answer the following:
Describe the key differences between oligotrophic and eutrophic waters in terms of their physical, chemical, and biological features (including food web differences). Based on these differences, which of these two conditions is most desirable and sustainable? (10 marks)
Identify five natural and five human generated sources of contaminants that lead to eutrophication of water bodies. Of these, which do you believe is the most challenging to regulate? Why? (10 marks)
Part B. Lake Winnipeg and Watershed Management (30 marks)
If you have not already done so, watch the Nature of Things production Save My Lake
Additional websites that may be helpful to you include:
Lake Winnipeg
https://www.manitoba.ca/sd/water/lakes-beaches-rivers/lake-winnipeg.html
Environment and Climate Change Canada Water and the Environment
https://www.canada.ca/en/environment-climate-change/services/water-overview.html
Using the video Save My Lake as your guide, you should note that there are numerous strategies to manage water quality and promote the sustainability of Lake Winnipeg. Based on the video and your independent research, provide answers to the following:
Describe the key features of the Lake Winnipeg watershed that make this lake particularly vulnerable to eutrophication.
(10 marks)
Review water chemistry data from 1999 to 2016 for three rivers that discharge into Lake Winnipeg, as found in Figures 1 and 2. (10 marks)
Outline the general trends in nitrogen and phosphorus concentrations that occurred over the years of the study;
Outline the differences in nitrogen and phosphorus concentration between the three rivers examined in the study;
What factors do you think may have contributed to the variability observed in the data between years of the study?
Based on these results, what recommendations can you make regarding the management goals and priorities for Lake Winnipeg water quality improvements?
Thinking back to the features of the phosphorus and nitrogen cycles, explain how humans have altered the ways these chemicals should naturally move in the environment. What other sources of nutrients (describe 4) do we need to control as homeowners concerned for their watershed’s water quality and why? (10 marks)
Figure 1 Status of phosphorus and nitrogen levels in Lake Winnipeg, 2016, and its 3 largest tributary rivers, Canada, 2014 to 2016
Note: The dotted line shows the objective or criteria value of 0.05 milligrams of phosphorus per litre (mg P/L) for Lake Winnipeg, 0.058 mg P/L (an average of the seasonal objectives) for the Saskatchewan River, 0.102 mg P/L for the Red River, and 0.012 mg P/L for the Winnipeg River. The solid (blue) line links the symbols to show the tendency in the average values. For the north basin and south basin and narrows, data are seasonally-weighted averages and vertical bars show annual minimum and maximum concentrations. For the Saskatchewan, Red and Winnipeg rivers, each boxplot summarizes annual phosphorus levels at a monitoring site and shows the range of values measured.
Source: Manitoba Sustainable Development and Environment and Climate Change Canada.
Source: https://www.canada.ca/en/environment-climate-change/services/environmental-indicators/nutrients-in-lake-winnipeg.html
Figure 2 Annual total nitrogen concentrations in Lake Winnipeg and its 3 largest tributary rivers, Canada, 1999 to 2016
Note: The dotted line shows the objective or criteria value of 0.75 milligrams of nitrogen per litre (mg N/L) for Lake Winnipeg, 0.80 mg N/L (an average of the seasonal objectives) for the Saskatchewan River, 1.4 mg N/L for the Red River, and 0.44 mg N/L for the Winnipeg River. The solid (blue) line links the symbols to show the tendency in the average values. For the north basin and south basin and narrows, data are seasonally-weighted averages and vertical bars show annual minimum and maximum concentrations. For the Saskatchewan, Red and Winnipeg rivers, each boxplot summarizes annual nitrogen levels at a monitoring site and shows the range of values measured.
Source: https://www.canada.ca/en/environment-climate-change/services/environmental-indicators/nutrients-in-lake-winnipeg.html
Go to the website to find information Annual total phosphorus concentrations in Lake Winnipeg and its 3 largest tributary rivers, Canada, 1999 to 2016
