LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
NOTE: The exercise described here is a portion of what is covered in Lesson 4: Measuring
Watershed Health Part II – Data Collection (included in CFWEP’s Base-level curriculum). It is
a follow-up of what was covered during Lesson 3: Measuring Watershed Health Part I –
Biological Indicators. In lesson 3, students were introduced to: 1) the structural layers of the
riparian vegetation; 2) categories of plant types found within each structural layer; and 3) the
datasheet used during the vegetation assessment.
Practice Vegetation Station
Objectives:
In this current lesson, which is part of Lesson 4: Measuring Watershed Health Part II – Data
Collection, students are given the opportunity to practice how to use the equipment and
complete the datasheet used for the riparian vegetation assessment.
Materials* (Figure 1):
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Assembled pictures of structural
layers of riparian vegetation (see
below for picture assembly
instructions)
Tent pole (should extend to about 5
m long)
Masking tape
Scissors
30-m transect tape
Practice datasheet for vegetation
CFWEP Plant Guide for Kids
*For classes with more than 10 students, double all materials and set-up two (2) transects.
Procedure:
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Pictures representing the structural
layers of the riparian vegetation are
hung on the tent pole and taped to a
wall, serving as a mock transect (Figure
2).
The transect consists of 5 sets of
pictures placed about 1 meter apart on
the tent pole (Figure 2).
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
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A set is made up of 3 pictures: the top picture is a common
view of overstory components; the middle picture shows
understory components; and the lower picture (resting
on the ground) shows ground cover components (Figure
3).
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Secure with masking tape, the 30-m tape measure onto the ground cover pictures (Figure 4
and 5). Be sure to place the “1 m” mark in the center of the first ground cover picture; the “2
m” mark on the center of the second ground cover picture; and so on.
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
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Direct students to collect data based on what they
observe in the pictures using the practice
datasheet (a modified version of the vegetation
datasheet; Figure 6).
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Be sure to emphasize the use of the codes to
record data (codes were explained to students in
Lesson 3).
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After completion of both the practice vegetation
and water quality stations, discussions follow.
Directions for Assembling Pictures
Materials:
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Pictures of structural layers of riparian vegetation
o 5 each of overstory, understory and ground
cover for 15 total; see CFWEP web page for
pictures: www.cfwep.org
o Highly recommended that all pictures be
laminated; good alternative is to use sheet
protectors
10 metal key rings
Roll of string
Hole puncher
Assembly Instructions:
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Punch holes in pictures (Figure 7):
o 4 holes for overstory picture (2 at top and 2
at bottom)
o 4 holes for understory picture (2 at top and 2
at bottom)
o 2 holes for ground cover picture (2 at top)
Cut 20 pieces of string approximately 50 cm long
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
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Tie string to bottom of overstory pictures and top of understory pictures
Tie string to bottom of understory pictures and top of ground cover pictures (Figure 8)
Insert the key rings to the top of the overstory picture (Figure 9)
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For some background information on the structural layers and biodiversity involved with
riparian vegetation assessment, please see Background Information following water
quality instructions.
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
Practice Water Quality Station
Objectives:
In this current lesson, which is also part of Lesson 4: Measuring Watershed Health Part II –
Data Collection, students are given the opportunity to practice how to use the equipment used
for the water quality station.
Materials:
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Practice datasheet for water quality (Figure 10)
GLX multi-meter (2-3) (Figure 11)
Sets of 6 labeled cups for water samples
(including rinse water cup; 2-3 sets; Figure 12)
Table salt and small caps or cups (for distributing
salt)
Mine tailings
Berkeley Pit water (if available)
Plastic spoons
Paper or cloth towels
Masking tape (for labeling cups and station)
Permanent marker
Scissors
Healthy parameters sheet (laminated)
Definitions handout
Instructions for Assembling GLX Multimeter
Cans of pop (preferably dark-colored pop)
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
Procedure:
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Before students arrive, set up 2 to 3 water quality stations around the classroom, but not
too far from each other. Each station should have: a GLX multimeter; 5 labeled cups for
water samples; 1 labeled cup for rinse water; a cup with salt (Figure 11); a spoon; a cloth
towel; the Healthy Parameters sheet; the Definitions handout; and the Instructions for
Assembling GLX Multimeter.
5 cups should be labeled with masking tape and marker as follows: 1) tap water; 2) tap
water & salt; 3) soda (or pop); 4) tap water & tailings; and 5) Berkeley Pit water. One
more cup should be labeled as rinse water.
Fill 3 of the water samples cups and the rinse water cup with tap water; fill 1 other cup with
soda (pop); leave the last cup labeled pit water empty until further instructions.
Label the station as Station 1, Station 2, etc (Figure 12).
Notify the students that they are going to practice using the GLX which they will use in the
field to determine water quality. Also inform students that the GLX is a piece of equipment
used by actual scientists to study water quality. Lastly, caution students to be very
careful with the equipment.
In addition, warn students about the dangers of tailings and pit water. These items can pose
health hazards and great care should be taken not to spill water samples or spread tailings.
Instruct the students to follow the directions on the Instructions for Assembling GLX
Multimeter and assemble the GLX’s.
Next, instruct the students to read through the practice datasheet and follow instructions as
written.
Remind students that, as written in the directions, they MUST rinse each probe between
each water sample measure in the rinse water cup.
The students should record their results on the practice datasheet (a less dense version of
the field datasheet). At this point inform students that they will only measure water pH,
conductivity and temperature for practice. In the field, several more measures will be
conducted and recorded.
For some background information on the water quality parameters involved with water
quality assessment, please see Background Information below.
After both stations are completed by all student groups, go over data and discuss results (see
lesson plan for Lesson 4).
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
BACKGROUND INFORMATION
Vegetation Background:
The Overstory (canopy) Layer1
The overstory (also called the canopy) is the highest vegetative layer. In CFWEP’s
study, the overstory is defined as any vegetation over 30 meters tall. The primary vegetation
found in the overstory is mature trees. The overstory is filled by leaves of mature trees. During
the growing season, overstory leaves intercept much of the sunlight available to the lower layers.
Typically less than 50% of the total amount of sunlight can pass through the overstory to plants
in the lower layers.
In a deciduous forest, the overstory is typically the last layer to show green in the spring.
Since the overstory trees receive sunlight throughout the growing season, they can wait longer to
deploy their leaves. This reduces the risk of the young tender leaves being destroyed by a late
freeze.
The Understory Layer1
Just beneath the overstory is the understory. In CFWEP’s study, the understory is
defined as any vegetation between 0.5 and 30 meters tall. It is common to find other studies
that split the understory layer into, sometimes up to 3 additional categories. The primary
vegetation found in the understory includes tree saplings, small shade-tolerant trees,
shrubs/bushes, and tall herbaceous plants. The understory can be thought of as a tree sapling
staging ground. In a mature forest, many saplings can claim enough nutrients and sunlight to
reach the understory. However, further growth is typically impractical as the saplings cannot
obtain enough additional nutrients from established overstory trees to grow any higher.
Therefore, many saplings slow their growth and wait in the understory until a mature overstory
tree dies. How well a sapling can grow in full shade and how long a sapling can survive in the
understory are two principle measures of a tree's shade tolerance.
When a mature tree dies and opens a gap in the overstory, all of the saplings waiting in
the understory rush upward. The saplings quick growth is fueled by the sudden increase in
sunlight and nutrients no longer claimed by the deceased tree. The race to reach the overstory is
very much a race for survival. There is typically only room for one new tree in the overstory. The
tree that reaches the overstory continues to grow and expand, gradually reducing the flow of
sunlight and nutrients to the trees below. All saplings that committed to the growth race, but
failed to reach the overstory, gradually weaken and eventually die.
The understory typically provides an abundance of food for animals such as deer and
bears. In fact, many plants of the understory depend on wildlife to distribute their seeds. The
animals ingest the plants' fleshy fruits and distribute the seeds in their feces.
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
The Ground Cover Layer1
The ground cover layer is the layer closest to the ground. In CFWEP’s study, ground
cover is defined as any vegetation from the ground up to 0.5 meters tall. In addition, for our
studies, ground cover also includes bare ground (includes dead plant matter), rocks, and
tailings. The primary plants of the ground cover include tree seedlings, herbaceous plants, and
grasses. Plants of the ground cover are typically the first plants to turn green in the spring.
These plants have to deploy their leaves early in the growing season to capture direct sunlight to
kick-start their growth cycle. Once the understory and overstory plants have deployed their
leaves, very little sunlight remains for plants in the ground cover layer. Many plants in the
ground cover layer have short life cycles.
Since CFWEP’s curriculum is geared towards comparing unimpacted, less impacted or
restored field sites to impacted field sites, we have also included the recording of other plants of
the ground cover layer that reveal information regarding the health of the riparian vegetation.
Specifically, we ask students to identify pollution-tolerant plants (tufted hairgrass and
saltgrass), moisture-loving plants (sedges and rushes) and bare ground with tailings.
Information on plant layers was modified from descriptions obtained from the following
web page: http://www.mightytrees.com/science/foreststrat.html.
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Water Quality Background:
What is water quality? The term water quality is generally used to describe the
chemical, physical and biological characteristics of water with respect to its suitability for its
many particular uses. For example, water quality as it relates to drinking water has different
requirements than water suitable for fish and other aquatic life, not to say that water safe for
drinking will not support other uses. The point here is that there is a lot to consider when
determining water quality. Even when looking at the data from scientific field monitoring, it is
not as simple as saying “this water is good” and “this water is bad.”
The quality of water we drink, and the quality of water in our rivers, streams, and lakes is
important to all life. Water pollution can sometimes be detected visually or through an unusual
odor. Often, the contaminants or pollutants cannot be detected by sight or smell, but they are
there none-the-less. Even in small quantities, some of these substances can cause harm, or
even be toxic to the living organisms that rely on the water. The effects of mining on water can
be tested in rivers and streams many years after mining operations have ceased.
In addition to practicing how to use the GLX multimeter, the exercise associated with
this lesson also provides the opportunity to explain to students what pH and conductivity mean
in relation to water. In addition, this exercise can demonstrate how tailings change water
quality and why tailings are harmful for fish and bugs. The use of the temperature probe is
simply to allow students to practice attaching and using the probe.
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
What does conductivity measure?
Conductivity (also called specific conductance) is a measure of a material's ability to
conduct an electric current. Specifically, conductivity measures the dissolved load –
materials that cannot be seen in solution. The conductivity of a solution of water is highly
dependent on its concentration of dissolved salts and sometimes other chemicals which tend to
ionize in the solution. Electrical conductivity of water samples is used as an indicator of how
salt-free or impurity-free the sample is – the purer the water, the lower the conductivity.
Conductivity is used as a water quality indicator. Conductivity is measured in units called
microSiemans per centimeter (µS/cm). The typical conductivity of Montana streams and rivers
is about 50-500 µS/cm. Polluted freshwater typically has a conductivity above this range.
Conductivity values are neither good nor bad. In other words, high conductivity does
not necessarily indicate pollution. For example, ocean conductivity is very high due to salts and
other minerals, and yet ocean waters support a great diversity and abundance of life. What is
important with respect to conductivity and water quality is the nature of the dissolved material.
In our watershed, high conductivity of fresh stream or river water may be indicative of dissolved
heavy metals such as copper, zinc, and iron. These heavy metals are can cause aquatic life great
harm.
Common factors that affect conductivity include low flow conditions (less dilution of
high salt content input sources), temperature and pH, especially if there are significant amounts
of metals in the water. This latter phenomenon is manifested best by looking at acid rock
drainage (ARD), which produces sulfuric acid through the oxidation of iron pyrite. Most metals’
solubility increases as the acidity of solution increases (as the pH decreases).
What does pH measure?
Two charged particles, H+ and OH-, are what make up pure water. Remember that water
in the environment is never pure; it is an aqueous solution containing many dissolved salts and
even gases. The pH of a solution is a measure of the amount or concentration of the H+ ions in a
solution, which tells us if our water solution is an acid or a base.
pH is measured in standard units on a logarithmic scale ranging from 0 to 14 (see figure
at right). Logarithmic means that measurements on
the scale increase or decrease by a power of 10. A pH of
4 is 100 times more acidic than a pH of 6, and 1,000
times more acidic than a pH of 7, and so on. Absolutely
pure water, or a solution that is neither acidic or basic,
measures at a pH of 7 (right in the middle of the scale).
We call solutions with a pH of 7 neutral. If
there are more H+ ions in solution than OH-, the pH
will be less than 7, or acidic. Common examples of
acidic solutions include vinegar and sulfuric acid (used
in car batteries). If there are more OH- ions than H+,
the solution will be above 7 or basic. Examples of
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LESSON 4: Measuring Watershed Health Part II – Data Collection
FIELDTRIP PRACTICE EXERCISES
simple bases are sodium hydroxide (baking soda) and ammonia. Bases can be thought of as the
chemical opposite of acids. A reaction between an acid and base is called neutralization.
The pH of healthy, natural streams and rivers in Montana fall anywhere between 6.5 and
8.5, meaning they can be slightly acidic or basic, or near neutral (as these pH values are also
called). Any stream or water source with a measurement outside of this range (either more
acidic or basic) indicates that some human impact (e.g., pollution) or natural process is
changing the chemical state of the water. For example, runoff from abandoned mines or mining
wastes high in iron pyrite can significantly lower the pH of a stream. This process, facilitated by
the oxidation of the pyrite which releases sulfuric acid into the environment, is known as acid
rock (or mine) drainage (ARD). Conversely, streams that are fed by groundwater in
limestone geology tend to have a higher or basic pH. This phenomenon is caused by the
geologic dissolving of CaCO3 into water which results in formation of bicarbonate, a basic or
alkaline substance.
Temperature is another physical parameter of water that refers to how cold or warm
the stream is. In water quality monitoring and scientific field research, temperature is measured
in degrees Celsius. Celsius temperature data can be converted to Fahrenheit by multiplying the
Celsius reading by 9/5 and adding 32. The majority of trout streams in Montana require a
temperature of 15-19 °C or 60-65 °F. Recording temperature of a site’s stream water is
important because dissolved oxygen levels (source of oxygen used by aquatic organisms)
decrease as water warms up. Also, the growth rates of aquatic plant and animal life increase
with a rise in temperature, which can lead to excessive algae growth and increased turbidity
(cloudiness) of water. Some common phenomena that can influence water temperature include
groundwater inflow, streamside vegetation (shading, or a lack of it) and water depth.
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