This lab focuses on stream features and on the use of a stream reach inventory to evaluate the potential for a stream channel for biologic activity and the long term stability of the channel. You will be using an inventory tool created by Pfankuch 1975. The manual and score sheet are available on the course website.
From the manual… “the purpose…is to provide information about the capacity of streams to adjust and recover from potential changes in flow and/or increases in sediment production.”
You should have no trouble locating a stream that can be evaluated using the tool. A reach can be defined as a segment of a stream with inherent similarity that can be easily identified and described.
Two papers describing the use this tool are also attached with the other documentation. Reading these papers will give you additional insight to the use and application of this sort of inventory.
Data and Methods:
The scoring rubric created by The USDA Forest Service Northern Region (http://www.biol.canterbury.ac.nz/ferg/pdfs/Pfankuc... (Links to an external site.). This is a classic tool that has been used in a variety of regions.
This is a very robust tool, and can be used by individuals with very little training to create accurate quantitative evaluations of streams.
Remember your write up should be structured in the same format of this assignment. The Introduction section should describe the purpose of the lab. The Data and Methods section should briefly describe the tool used. The Analysis section should include your map, photos, and a discussion of the scores and an analysis of the overall scores.
Where is your stream? Please include a map. Photograph your stream and include this with your lab write up.
What is the score for each stream reach you evaluated? Does this score ‘make sense’?
What item/category provided the ‘lowest’ (worst) score for your streams?
Would it be possible to mitigate this factor and improve the overall quality of the stream reach? Describe your mitigation strategy.
If you were responsible for managing these streams, what actions would you propose to improve the overall rating of the individual reaches?
What would have more impact, to raise all the streams in your management area to “good” or focus on a very limited number of stream reaches and raise them to ‘excellent’ status?
What evidence can you see of changes in the stream channels?
It is not necessary to include your score sheets with your lab. A map, photos, scores and write-up will be sufficient.
From the instruction booklet:
After beating the brush, getting your feet wet, and fighting insects, you have established a series of channel ratings. You may now ask “What do these numbers mean and how are they used in making management decisions?.... The numbers and adjective ratings mean what they say. A stream channel reach with a ‘poor’ rating will require more judicious management of the tributary watersheds than one rated ‘excellent’....One of the uses of this rating system is to assess conditions and define impacts along short stretches of stream. Channel conditions can be evaluated in terms of stream stability and potential for damaging water quality at culvert or bridge sites, campgrounds or administrative facilities, or sites where livestock or wildlife concentrate near or across the water course’ . Prudent managers will seek trend data by periodic reappraisal of channel conditions and respond to adverse changes before impacts to the water resource become unacceptable and unalterable.