using multiple indicator monitoring protocols. what is mim streambank alteration? the number of...
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Using Multiple Indicator Monitoring Protocols
What is MIM Streambank Alteration? The number of lines on the plot that
intercept hoof prints, hoof shears – disturbances caused by trampling.
5 lines per frame – one sample At least 80 samples per site – total of
400+ lines % Streambank Alteration = the
proportion of the 400+ lines that intercept hoof prints/shears
MIM Bank Alteration
80+ plots -400 Samples
Hoof Print & Hoof Shear Dimensions Average width = 120.8 mm Average length =171.8 mm
230mm
120 mm
Bank Shear and Tramples
Why use a simple intercept method? Simple = more efficient Simple = better agreement among
observers
Variability Among Observers – Various methods GLP: SD = 4.7, CV = 56 GL : SD = 6.3, CV = 20 BF: SD = 8.1, CV = 35
MIM (35 tests): SD = 4.3 , CV = 22.7
Heitke et.al. 2008
MIM estimates length of greenline altered: MIM: 4 “Hits” =
80%
LENGTH OF GREENLINE (within 1 hoof print ) altered = 90%
AREA OF PLOT altered = 60%
Typically the vegetated side of the greenline has fewer alterations
Simultation using actual hoof print dimensions
Results
• High Regression Coefficient• 1:1 relationship (.91 X MIM)
• Lower Regression Coefficient• 1:3 Relationship (.32 X MIM):
•MIM 20% - AREA 10%•MIM 40% - AREA 16%•MIM 60% - AREA 23%
Proper Use of Bank Alteration As a short-term indicator of disturbance
effects on bank stability and vegetation Any value assigned as a trigger to move
livestock or as a measure of grazing use is a “guideline” which must be able to change through time (See Cowley 2002)
Thus a “Term and Condition” should incorporate an adaptive process.
Bank Alteration and Bank Stability
Hartrig g er C reek
0%10%20%30%40%50%60%70%80%90%
100%
2004 2005 2006 2007 2008 2009 2010
Yea r
Per
cen
t
B ank A lteration
B ank S tability
EF Deer CreekDominant VegetationPOPR– 65%MFE – 22%JUBA – 12%SCMI – 3%% Hydric – 19%
October 2009Bank alteration:1%Bank stability: 70%
Nick Stiner, Malheur NF – Fall 2009
Christopher Christie photo 2008
June 2009
Sept. 2008Bank alteration: 24%Bank stability: 51%
June 2009Bank alteration: 4%Bank stability: 67%
Cowley 2002 – Lit Summary “Little research data is available concerning
the amount of streambank alteration that a stream can tolerate and repair each year.”
“Each of the authors mentioned above recognizes the ability of streams to repair a certain amount of bank alteration”
“The further a streambank is from the desired future condition, the less additional alteration it can tolerate and still recover to a stable level.”
Amount of Alteration that streambanks can repair annually depends upon: Stream gradient Streambed material composition, Streambank soil composition, Vegetation cover and type Channel geometry, Flow rate and timing, and “. . . concentrated impacts under rotation systems
can cause sufficient woody plant or streambank damage in a single season or year that recovery might take several years. Therefore, the best approach is to limit grazing stress to the site’s capability for annual recovery.” (Clary and Kruse 2004)
A Rational Approach to Bank Alteration Criteria and Standards Existing Condition: Compare existing
condition to a reference (best method)Bank Stability (%): Bank Cover (%): Hydric herbaceous vegetation (%)
○ (closer these are to reference the higher the allowable level of bank alteration)
Channel Type: >gradient = higher allowable level> particle sizes = higher allowable level
The Confidence Interval Any criteria requires consideration of the
precision of the measurement. CI for Streambank Alteration
32 tests○ Maximum – 11%○ Minimum - .5%○ Average – 6%
Using the CI: Set trigger at allowable level minus 6%Set standard at allowable level plus 6%e.g. If allowable level is 20%, trigger might be
set at 14%, and term and condition set at 26%.