Water in the World:
Lake Trophic State, Topography and Water Quality Analysis Teacher Guide
Developed by Chris Christensen
Agricultural Education Teacher, Marshall, MI
Michigan High School Content Expectations01.0
Agriculture, Agricultural Operations and Related Sciences (AS)
XVC
1. Describe ecosystem stability. Understand that if a disaster such as flood or fire occurs, the
damaged ecosystem is likely to recover in stages of succession that eventually result in a
system similar to the original one.
2. Recognize and describe that a great diversity of species increases the chance that at least
some living organisms will survive in the face of cataclysmic changes in the environment.
3. Examine the negative and positive impacts of human activities on the environment
XVC Interdependence of Living Systems and the Environment--Changes in Ecosystems
XIXB Water Resources-Watersheds
1. Understand the role of watersheds.
2. Explain how water enters a watershed
6. Analyze how land use variations in a watershed can effect the runoff of water
XIXE Water Quality
1. Interpret the importance of high quality water
2. Identify and explain factors that influence the quality of water
XIXF Wetlands and Stream Ecology
1. Explain and describe characteristics and types of wetlands
2. Describe and explain the physical factors that affect a stream and the organisms living there
Time Frame: 90 Minutes (may require more times depending on areas included)
Materials/Equipment:
White Board, Chalk Board or Butcher paper to create lists.
Computer and projector for PowerPoint presentation
Computers with access to Google Earth
Exercise Question sheets
Lime Lake Information Sheets
Benthic Organism Identification Sheets
Teaching Procedure:
A. Interest Approach
We have been discussing lake tropic types and today we will do a practical exercise utilizing
Google Earth to view different lake sites and utilizing known data to assess the tropic state and
why those conditions might exist viewing the watershed which feeds that site.
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General Information:
We will be looking at lakes today, analyzing data and using a bird’s eye view trying to make
sense of the data. Some of these water structures have a small local watershed with no outlet and
are tied into the groundwater (as all lakes are to some extent). Wall Lake is part of the Grand
River watershed; what difference does that make as you look at Upper Crooked, Lower Crooked
and Gull Lakes which are connected and part of the Kalamazoo River Watershed? Look at land
utilization and review the water quality data; it changes sometimes and improves. Why?
1. Once you have Google Earth opened, go to the tools menu to change from the English to the
Metric scale. Input Lake of the Clouds Porcupine Mountains State Park, Michigan ( 460 48’
20.95” N 890 44’ 45.44” W). The elevation should be about 327 m (0.203 miles).
2. Fly to Wall Lake (420 31’ 14.65” N 850 23’ 16.44 W). Wall Lake is part of the Grand River
watershed. Complete the questions on the answer sheet.
3. Fly to the Blachman’s Swamp (420 29’ 56.73” N 850 23’ 13.90 W). A unique feature of this
peat bog is that it is precipitation fed and is the dividing point between the Grand River and
Kalamazoo River watersheds. Think carefully about the data and what that means for
aquatic creatures.
4. Fly to Upper Crooked Lake (420 29’ 42.59” N 850 25’ 50.60 W). This lake is the first in a
series as part of the Kalamazoo River watershed. Look at the trends as you move downstream
how does land utilization change and impact water as you move downstream.
5. Fly to Lower Crooked Lake (420 27’ 55.77” N 850 28’ 00.53 W)
6. Fly to Pond 10 (420 28’ 15.19” N 850 27’ 40.09 W). Pond 10, like many small Michigan
lakes and ponds, is unique. It is a separate small ecosystem tied in by groundwater to the
greater watershed.
7. Fly to Gull Lake (420 24’ 20.77” N 850 24’ 55.71 W). Note the land utilization patterns. Do
they seem to match the water quality data?
8. Fly to Evergreen Lake (420 23’ 52.28” N 850 23’ 03.86 W)
9. Fly to Lime Lake (440 25’ 13.65” N 890 20’ 43.53 W). This lake is a marl type groundwater
fed lake.
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Water in the World:
Lake Trophic State, Topography and Water Quality Analysis
(ANSWERS)
1. Using the photos (the overhead view will show clouds hence the name), categorize this lake
body based on its location, elevation and surrounding features and explain your answer.
Lake category Oligotropic
Lake of the Clouds is an Oligotropic structure. The lake is located in a high hills
region within a state park. Minimal development has taken place and no farms or
homes are on the lake or impact the lakes water sources. The lake is quite shallow;
this in conjunction with the short growing season presents the issue of winter kill of
aquatic organisms and plants. The structure is unique because of the very limited
watershed that feeds it. The lake level and exit are at the same elevation level.
2. Look at the data provided for Wall Lake as compared to the other large lake bodies. Its
alkalinity is lower, pH more toward neutral, and conductivity is the lowest of the lakes. Why
is this the case?
Water in Wall Lake is part of the head waters of this portion of the Grand River
watershed. As a result, fertilizer residue from farm fields is negligible. The major
pollution source is from the homes on the lake. As a result we have low alkalinity,
conductivity, and fairly neutral pH. The sekki reading still indicates mesotropic
condition.
3. The bog has unique characteristics. How do you explain that all the data is on the low end
and the only structure close to it is pond 10?
The bog sits on the dividing line between the Grand River and Kalamazoo
Watersheds. It is essentially a closed system as the only water coming in is from
precipitation. Dilute acidic water, sphagnum moss, and blueberry shrubs
predominate. The mass of material decomposing results in low oxygen levels and
very low sekki depth readings. Pollution from the area is negligible.
4. What is the land utilization around Upper Crooked Lake? How is this reflected in the data?
About 50% of Upper Crooked Lake has home sites. However its water shed is
surrounded by farm fields resulting in high alkalinity, conductivity, plant growth,
and high oxygen levels caused by fertilizer runoff.
5. Review the data for Lower Crooked Lake and compare it to Upper Crooked Lake. How do
you explain the changes?
Lower Crooked is lower in nearly all categories as a result of being down steam
from Upper Crooked and Middle Crooked. It has a much larger watershed; homes
around the lake are also limited as the west and north sides are part of MSU. The
dilution results in lower conductivity, alkalinity, pH, and less plant growth (lower
oxygen level) than Upper Crooked. The farm lands near the lake have also
maintained riparian buffers to limit pollution runoff.
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6. Pond 10 is very close to lower Crooked Lake. How do you explain the dramatic differences
in the data collected?
Pond 10 is a small ecosystem that is separated from Lower Crooked Lake but
connected to it by groundwater. The area around Pond 10 is non-agricultural.
Pond 10 is shallow with deep muck and heavy plant growth on the outside but clear
in the middle.
7. What are some of the impacts of land utilization on Gull Lake?
Gull Lake has had vacation homes for many years; the majority of yards go down to
the waters edge so fertilizer pollution is a problem. As a result of pollution,
conductivity, and pH have risen. One complicating factor is that Gull Lake is
heavily infested with Zebra Mussels. As a result the water is quite clear from the
filtering of these organisms.
8. Categorize the lake type for Wintergreen. Eutrophic
How do you explain some of the differences in oxygen level at similar depths between
Wintergreen and Gull Lakes?
Wintergreen is a very Eutropic with heavy plant growth. It has a higher oxygen
level at the surface but very low at the bottom as oxygen is consumed by decaying
organisms. Conductivity is also very high indicating contaminated fertilizer or
manure runoff into this water body. The lake bottom is very mucky.
9. What will be the major influencing factors for Lime Lake in the future (what will cause
major changes in water quality)? Look at current land use and where the water feeds for the
lake are located.
Lime Lake is mostly groundwater fed. As a result, any change to the local watershed
will impact it greatly. If the farm close to it closes down and native grasses are
planted the lake will proceed toward a more original state. However, more intensive
farming practices or residential development would result in additional fertilizer,
pesticides, and runoff and cause a more rapid movement towards Eutropic state.
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