riparian/land use/bank erosion
Post on 23-Feb-2016
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Riparian
Max 10
4]. RIPARIAN ZONE AND BANK EROSION-(check ONE box per bank or check 2 and AVERAGE per bank) River Right Looking Downstream RIPARIAN WIDTH FLOOD PLAIN QUALITY (PAST 100 Meter RIPARIAN) BANK EROSION
L R (Per Bank) L R (Most Predominant Per Bank) L R L R (Per Bank) -FOREST, SWAMP [3] -CONSERVATION TILLAGE [1] -NONE/ LITTLE [3] -SHRUB OR OLDFIELD [2] -URBAN OR INDUSTRIAL [0] -MODERATE [2] -RESIDENTIAL,PARK,NEW FIELD[1] -OPEN PASTURE,ROWCROP [0] -HEAVY/ SEVERE[1] -FENCEDPASTURE [1] -MINING/ CONSTRUCTION [0]Comments:
- WIDE >50m [4] - MODERATE 10-50m [3]- NARROW 5-10 m[2]- VERY NARROW <5 m[1] - NONE [0]
- VERY WIDE > 100m [5]
Riparian/Land Use/Bank Erosion
Riparian Width
Riparian vegetation includes trees, shrubs and wetlands; not grasses
Select one width or two and average for each bank, then average banks together
Woody Riparian Quality
Effects increase in importance as they accumulate in a watershed: Death of a Thousand Cuts!
Habitat forming functions
Bank stabilization Retention/uptake of
excess water Groundwater
recharge/maintenance of dry weather flows
Assimilation/storage of nutrients and sediment
Temperature moderation
In streams with good habitat, good riparian shading and elevated nutrients, effects of these nutrients may be somewhat moderated by limiting light penetration
Sunlight is match thrown on nutrient fuel
Shading
Riparian Condition
0
10
20
30
40
50
60
70
80
0 20 40 60 80 100
Average Riparian Width (QHEI )Selected OhioWatershed
MoxahalaFederalLittle MuskingumLittle BeaverWabash
Aver
age
Ripa
rian W
idth
Percent of Sites
Median
Adjacent Landuse
Area outside of existing riparian that can strongly affect stream via runoff
Screening data, most accurate data from photos or GIS
Land Use Assessment by GIS
Bank Erosion Scores based on
Streambank Soil Alteration Rating of Platts et al. (1983)
In many case bank erosion is greatest source of bedload
False banks are considered as eroded
Riparian encroachment ultimately leads to bank destabilization and bank erosion
Effects of Unrestricted Access by Livestock Herds: False Banks and Bank Erosion
False Banks False banks are
formed when stream banks are trampled by livestock and a steep bank is formed back from the waters edge
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