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Kushog Lake Physical/Chemical Parameters
Lake Fact Sheet General Characteris.cs
Municipality: Algonquin Highlands
Mean Depth: 9.1m Surface Area of Lake: 679 ha
Maximum Depth: 38.1 m Watershed Area (Excluding Lake): 7701 ha
Maximum Width: 1.6 km % Wetlands in Watershed: 10%
Shoreline Perimeter: 8.3 to 40.6 km Total Volume: 63 200 000 m3
North to South Length: 17.2 km ElevaFon: 332.8 mASL
Indicators of Lake Health
Created By: Emily McDonald & Caitlyn Bondy Trent University 2015. Community Based EducaFon Project carried out
through U-‐Links.
Key Terms Trophic Status: is a measure of lake producFvity and sensiFvity in terms of nutrient input. There are three trophic categories with respect to nutrient status:
Oligotrophic: less than 10 µg/L of total phosphorus Mesotrophic: between 10 and 20 µg/L of total phosphorus
Eutrophic: over 20 µg/L of total phosphorus Total Phosphorus: Total phosphorus concentraFons are ideally used to interpret lake nutrient status, since phosphorus is the element that controls the growth of algae in most Ontario lakes and is oUen a limiFng nutrient. High levels of phosphorus can lead to algal blooms. Secchi Depth: Is the measurement of water clarity. It is measured through the process of lowering a pole with a disc mounted on it and recording the water depth at which the disk is no longer visible. A decline in water clarity is usually indicaFve of a reducFon in water health. Algal Blooms: A “bloom” is an excessive growth of one or more species of algae. Algal blooms are less likely to occur in lakes that have low total Phosphorus (oligotrophic levels). Conversely, blooms are most likely to occur in lakes that have moderate to high total phosphorus (mesotrophic to eutrophic levels). They are important to monitor as they may affect water clarity, deplete oxygen levels and produce toxins harmful to the ecosystem. Calcium: Commonly enters the freshwater system through weathering of rocks, specifically limestone, and from soil through leaching and runoff. Dissolved Oxygen: It Is a measure of the concentraFon of oxygen dissolved in water. Major sources of DO in water are the atmosphere and photosynthesis by aquaFc life. Adequate concentraFons of dissolved oxygen are necessary for the survival of fish and other aquaFc organisms. pH: The measurement of how acidic or basic a substance is . Values range between 0 to 14. (1 – acidic, 7 – neutral, 14 – basic)
Ontario Standard
Guidelines
Kushog Lake
For an oligotrophic level:
< 10 μg/L
Total Phosphorus (20 year avg):
5.5 μg/L
N/A Average Calcium (2008 – 2012):
2.4 mg/L
Secchi disc visible at 1.2 m or more: 1.2 m
Secchi Depth (20 year avg):
4.77 m
pH standard:
Recrea.on: 5.0 – 9.0 Aqua.c Life: 7.0 – 8.7
Drinking Water: 6.5 – 8.5
pH (20 year avg):
6.74
Dissolved Oxygen:
5.5 mg/L -‐ 6.5 mg/L
Dissolved Oxygen (2003):
5.40 mg/L
Trophic Status: Oligotrophic
The analysis of the data collected regarding the key indicators for Kushog Lake suggests that this lake falls within the recommended standard values for acceptable health.
Map Provided by: Scholars GeoPortal
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
Calcium (m
g/L)
Data provided by: The Ministry of the Environment – Dorset Environmental Science Centre (Lake Partner Program) Health Canada – Ontario RecreaFonal and Drinking Water Standard Guidelines Canadian Council of Ministers of the Environment – Ontario AquaFc life Water Quality Guidelines Scholars GeoPortal
SpaXal and Temporal Analysis of ExisXng Data
0 1 2 3 4 5 6 7 8 9 10 11
1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013
Secchi Depth (m) TP(µg/L)
Oligotrophic
Phosphorus and Secchi Depth:
This line indicates the upper threshold for an oligotrophic status
Calcium:
0 5 10 150
5
10
15
20
Depth (m)
Dissolved Oxygen (mg/L)
25-Jul-02 Basin 204-Sep-02 Basin 2
0 5 10 15 20 250
5
10
15
20
Depth (m)
Temperature (°C)
25-Jul-02 Basin 204-Sep-02 Basin 2
Dissolved Oxygen and Temperature Profiles:
Interpretation: Phosphorus and secchi depth, combined, are the best indicators to determine trophic status of a lake. The concentration of nutrients within a lake, such as phosphorus, directly in:luences water clarity and consequentially the lake’s trophic status. Kushog falls within the range for an oligotrophic lake with less than 10 µg/L of total phosphorus. Secchi depth follows closely the trend in the phosphorus data points, and remains stable around 5 m. Overall, There is no consistent temporal trend over a 20 year period for either of the measurements.
Interpretation: The average calcium concentraFons shown are based on a four-‐year Fme period, between 2009 and 2012, for Kushog Lake and 9 other lakes within the Gull River Watershed. Kushog has an approximate average of 2.4 mg/L of calcium, which is fairly low as compared to several other lakes such as: Gull, Horseshoe and Moore. Gull Lake has approximately 7.1 mg/L of calcium, the highest of all Lakes displayed; whereas Big Hawk Lake has the lowest value of the 10 lakes, at approximately 1.7 mg/L. It is evident that there is significant variaFon between the 10 lakes. This variaFon may be amributed to regional differences in bedrock geology.
Interpretation: The verFcal profiles provided are based on samples obtained from the middle basin of Kushog Lake during July and September, 2002. Dissolved oxygen (DO) is highly correlated with temperature. The relaFonship between the two parameters is important, as the solubility of oxygen tends to decrease as water temperature increases. DO levels in Kushog lake average around 5.40 mg/L and remain relaFvely stable with increased depth. Water temperatures range between 20 °C to 25°C near the lake surface in summer but decrease with depth to only 8°C. DO should remain stable as it is imperaFve for the survival of fish species. Any future decline in DO could be amributed to increases in temperature of the water.