1. Riparian Areas: Functions and Conditions Authors: Gene Surber, MSU Extension Natural Resources Specialist Bob Ehrhart, Research Specialist, RWRP, Univ. of Montana

2. Riparian Areas Wetlands Riparian areas Overflow areas Wet meadows Marshes Sloughs

3. Characteristics of Riparian Areas “Green Zone” – link between aquatic and terrestrial Water Landform Soil Vegetation

4. Riparian Areas More dynamic than uplands Flooding Deposition of sediment Accumulation of organic matter Dewatering Changes in location

5. Functions of Riparian Areas 1. water storage 2. flow energy dissipation 3. water quality 4. sediment trapping 5. bank building and maintenance 6. primary biotic production

6. Store and Release Water Soil – acts like sponge Reduces flooding Extends time that surface water is available

7. Dissipate Energy of Flowing Water Slows water Vegetation Woody debris Large boulders Cobbles

8. Provide Water Quality Natural pollution control Trap sediments (nutrients, pesticides, toxic metals, bacteria)

9. Trap sediments Trap sediments – development of new streambanks and bars

10. Protect soil and water Shields soil and water from: Wind Sunlight Rain drop impacts

11. Enhances Productivity Most productive parts of a landscape

12. Provide wildlife habitat Water, food, cover and travel routes Birds Mammals Insects Fish

13. Evaluating the Health of Riparian Areas How well the riparian area carries out the functions Physical Biological

14. Evaluating Physical Features Channel downcutting Channel widening Amount, location, & causes bare ground Amount of fine materials Amount of rock

15. Downcutting “Incisement” = erodes away the channel bottom

16. Channel becoming wider & shallower Banks break down Stream becomes shallower Stream temperatures rise

17. Amount, location, & causes of bare ground Bare ground – erosion Noxious weeds Compaction or bank shearing

18. Amount of fine materials on channel bottom Silts, clays, decomposing organic material Not enough water running

19. Bank Rock Content Large rock versus Sand, silt, small gravel Management considerations

20. Biological Features Types & amounts of plants How well they fulfill functions Amount of foraging & browsing Mix of age classes of wood species

21. Streambank protection Vegetation Slows velocity Stabilizes streambanks Reduces erosion

22. Amount & Types of Vegetation Canopy cover of desired plants Noxious weeds

23. Presence of Trees and Shrubs Woody plants (trees & shrubs) Bank stabilizers Food & cover Determining appropriate presence

24. Woody species age class Distribution of age class All old trees All young trees

25. Degree of Browsing Excessive use (50% of current or previous year’s growth)

26. Woody Draws Perform functions of riparian areas Habitat Cover, food, water Grazing management plan