Zooey Diggory, Bruce Orr, Amy Merrill S T I L L W A T E R S C I E N C E S

1. SANTA CLARA RIVER PARKWAY FLOODPLAIN RESTORATION FEASIBILITY STUDYIntegrating invasive species management with riparian-floodplain restoration in the lower Santa Clara River Zooey Diggory, Bruce Orr, Amy Merrill S T I L L W A T E R S C I E N C E S Gretchen Coffman, and Tom Dudley U C S A N T A B A R B A R A

2. S A N T A C L A R A R I V E R W A T E R S H E D & A N A L Y S I S A R E A

3. P R E S E N T A T I O N OV E R V I E W • Historical Changes in Riparian Vegetation Extent • Influences on Riparian Vegetation Distribution & Composition • Vegetation-Process Linkages • Restoration & Invasive Species Removal Strategies

4. H I S T O R I C A L C H A N G E S I N R I P A R I A N V E G E T A T I O N E X T E N T • Literature Review • Flood Mapping

5. LITERATURE REVIEW • floodplain was as much as two miles wide in lowermost reaches(Simons, Li & Associates 1983) • dense, multi-stored stands of broadleaf trees that extended from a few to several miles wide(Roberts et al. 1980, Holland and Keil 1995, Boughton et al. 2006)

6. FLOOD MAPPING • Bare, partially- and highly-vegetated areas mapped after 6 major floods

7. I N F L U E N C E S O N R I P A R I A N V E G E T A T I O N D I S T R I B U T I O N & C O M P O S I T I O N • Riparian Vegetation Mapping • Vegetation Dynamics Analyses

8. RIPARIAN VEGETATION MAPPING • Accurate and current map of riparian vegetation (post-2005 flood)

9. VEGETATION DYNAMICS ANALYSIS • Canonical Correspondence Analysis (CCA)

10. V E G E T A T I O N – P R O C E S S L I N K A G E S • Climate • Flood Dynamics • Groundwater Availability • Floodplain Development • Invasion by Arundo Change background photo?

11. CLIMATE • Semi-arid, Mediterranean climate • Arid inland and moister, cooler coast

12. CLIMATE • Correlation between distance from river mouth and species distributions

13. FLOOD DYNAMICS • Vegetation reset after large floods, particularly in El Niño years FLOW pre-high flow JUNE 2002

14. FLOOD DYNAMICS • Vegetation reset after large floods, particularly in El Niño years FLOW high flow FEB 2005

15. FLOOD DYNAMICS • Vegetation reset after large floods, particularly in El Niño years FLOW post-high flow SEPT 2005

16. FLOOD DYNAMICS • Relative elevation and vegetation alliance distribution

17. GROUNDWATER AVAILABILITY • Gaining vs. losing reaches

18. GROUNDWATER AVAILABILITY • Vegetation alliances in gaining vs. losing groundwater reaches

19. FLOODPLAIN DEVELOPMENT • Agriculture • Levees and urban development

20. FLOODPLAIN DEVELOPMENT • 60 percent reduction in historical floodplain extent

21. INVASION BY ARUNDO • Replaces native vegetation • Alters ecosystem processes

22. RESTORATION & INVASIVE SPECIES REMOVAL STRATEGIES • Increase & Improve Floodplain Connectivity • Promote Revegetation via Natural Recruitment & Active Planting • Implement Strategic Actions to Control Arundo

23. INCREASE & IMPROVE FLOODPLAIN CONNECTIVITY • Acquisition & levee setbacks

24. PASSIVE & ACTIVE REVEGETATION • Allow natural recruitment in active floodplain • Focus active revegetation in areas not subject to frequent, resetting floods • Match target restored plant community types with site physical conditions 25-year floodplain (largest mapped flood on record) 1969 flood extent 500-year floodplain NATURAL RECRUITMENT (passive) PLANTING (active)

25. STRATEGIC ACTIONS TO CONTROL ARUNDO Remove arundo: • in an upstream to downstream direction • in fire-prone shrub lands • from watersheds and reaches with low nutrient levels • In the summer following major floods

26. ACKNOWLEDGEMENTS • Bruce Orr, Amy Merrill, Gretchen Coffman, & Tom Dudley • Coastal Conservancy & Santa Clara River Trustee Council • Bill Sears, Sebastian Araya, & Tami Cosio