Environmental Engineering Reference
In-Depth Information
Student Exercises
Laboratory Exercises
Laboratory Exercise #1: Spatial Variation in Water Quality
1. Select a study wetland with different habitat types that can be accessed to
determine water quality variables and develop a hand-drawn habitat map of
the wetland to delineate major habitat types and structural features (e.g., inlets
and outlets, stands of emergent, submergent, floating plants, open water). These
habitat types will be used to develop hypotheses and as sampling strata in Step 2.
2. Based on the different habitat types in the wetland identified in Step 1 and an
understanding of how wetland processes may influence water quality parameters,
develop a series of hypotheses or predictions related to how the water quality
variables being measured would be expected to differ between the habitat types.
For example, how would you expect temperature, dissolved oxygen, and pH to
compare between open water and stands of macrophytes?
3. Using a calibrated multi-parameter water quality meter, determine temperature,
dissolved oxygen, pH, and conductivity for each wetland habitat. Other water
quality parameters (e.g., turbidity, nutrients) may also be determined depending
on availability of equipment**. If the wetland has an open water zone that is
accessible by boat, use the water quality meter to generate a vertical profile
of the water quality parameters from just above the sediment surface to just
under the water surface. Space the measurements so that data are collected from
at least three depths.
4. Provide a brief summary of whether the data collected supported your
hypotheses and a brief discussion of the basis for the results observed.
5. Questions to consider:
What are some reasons for any observed differences in the water quality
parameters measured between the wetland habitat types?
How would you determine if any relationships exist between the parameters
measured? (i.e., dissolved oxygen vs. temperature vs. pH)
If relationships between parameters are observed, what is the basis for these?
**Water samples may also be collected in clean 1-L plastic bottles to take back
to the laboratory for determination of “wet chemistry” parameters such as nitrate,
orthophosphate, and alkalinity.
Laboratory Exercise #2: Temporal Variation in Water Quality
1. Select two or three different habitat types within a wetland and develop a
sampling schedule that allows collection of water quality data (temperature,
