Using a Historic Change Analysis to Design Strategic Restoration/Preservation of Nearshore Ecosystems in Puget Sound

Transcription

1 Using a Historic Change Analysis to Design Strategic Restoration/Preservation of Nearshore Ecosystems in Puget Sound Charles Si Simenstad Wetland Ecosystem Team School of Aquatic and Fishery Sciences University of Washington On behalf of the Puget Sound Nearshore Ecosystem Restoration Project (PSNERP) teams Restore America s Estuaries 2010 Restoring and Protecting Puget Sound s Nearshore Ecosystems; Tuesday, November 16

2 Message Historic change in nearshore ecosystem processes that sustain ecosystem functions, goods and services can be inferred from change in ecosystem structure Strategic planning of restoration and preservation can be informed by change analysis; where and what restoration/protection is needed cannot be arbitrary, i.e., more strategic by attending to types and scales of process change Puget Sound Nearshore Ecosystem Restoration Project s (PSNERP) Change Analysis forms foundational framework and geodatabase to identify and set priorities for nearshore restoration/protection to maximize benefit

3 Content 1. Role and approach of PSNERP Change Analysis in restoration/preservation planning 2. Synopsis of change in Puget Sound nearshore ecosystems 3. Implications for delivery of ecosystem functions, goods and services 4. Lessons learned

4 PSNERP NST: Change Analysis Restoration and Protection Portfolios Change Analysis: How have nearshore ecosystems changed? Strategic Needs Assessment: Where are the most problematic changes and why? Future Risk Assessment: How might future growth and development affect the nearshore? Science Guidance: restoration principles from literature and practice? Restoration and Protection Portfolios: What actions should we take and where? Management Measures: What can we do to protect and restore the nearshore?

5 So, what is wrong with Puget Sound s nearshore ecosystems?

6 Challenges: impediments to nearshore ecosystem restoration? adjacent upland development legacy contaminants point and nonpoint contaminant discharge freshwater flow regulation and diversion transportation and other public infrastructure Extensively industrialized Puyallup River delta

7 PSNERP CHANGE ANALYSIS Objective Infer magnitude and significance of impairment in nearshore ecosystem processes from historic changes in physical structure of nearshore environment consistent with conceptual model of relationships among ecosystem processes, structure and function. Approach Assess change in types and magnitude of historic changes in natural nearshore ecosystems over last ~ yr (~ to ), not as target for restoration but as guidance Scope and Focus comprehensive, Sound-wide along ~4,000 km shoreline spatially explicit changes in nearshore ecosystem processes ( process-based landscape/ecosystem organization 1907 Ashel Curtis photograph of Everett, Washington from Rucker Hill

8 CONCEPTUAL BASIS - PSNERP ECOSYSTEM STRUCTURE + components ECOSYSTEM PROCESSES Regional weather tectonic events tidal flooding wave energy Local hydrology (tidal and current movement) freshwater inflow sediment erosion & accretion particle transport Finite biogeochemical processing/cycling primary production food web transfer and connectedness decomposition reproduction ECOSYSTEM FUNCTIONS Millennium Ecosystem Assessment (MA 2003,2005; de Groot et al. 2002, etc.) Supporting fish and wildlife habitat biodiversity Provisioning food production food web sources coastal sediment supply Regulating wave attenuation sediment retention flooding mediation gas regulation Cultural recreation aesthetics science and education ecological interactions behavior

9 Nearshore Ecosystem Processes Examples of local ecosystem processes: Sediment Supply and Transport: supply (from bluff, stream and marine sources) and transport of sediments and other matter by water and wind Beach Erosion and Accretion: erosion and deposition (accretion) of sediments and mineral particulate material by water, wind and other forces Tidal Hydrology: localized tidal movements, differing from regional tidal regime mostly in tidal freshwater and estuarine ecosystems Localized Wind and Wave Inputs to the Shoreline: exposure to winddriven waves Distributary Channel Migration: combined freshwater and tidal flow influences on distributary channel form and location Tidal Channel Formation and Maintenance: geomorphic processes, primarily tidally driven, that form and maintain tidal channel geometry Freshwater Input: freshwater inflow from surface (streamflow) and groundwater (seepage) and mixing with seawater Detritus Recruitment and Retention: import and deposition of particulate (dead) organic matter Exchange of Aquatic Organisms: organism transport and movement Solar Radiation: exposure to solar radiation and resulting effects (e.g., radiant heat)

10 PSNERP Change Analysis: Shoreforms Stream delta Vegetated flat BARRIER Channels ESTUARY Tidal flat Tidal delta Alluvial River Valley Coastal Watersheds Embayments Bedrock Upland Vegetated Flats Tidal flat BARRIER Tidal delta LAGOON Channels Berm/Backshore Beachface Low-tide terrace BARRIER BEACH Cliff ROCKY Platform PLATFORM Alluvial Floodplain (surge plain) High tide flat Low tide flat RIVER DELTA Bluff face Berm/Backshore Beachface Low tide terrace BLUFF Berm/Backshore BARRIER Beachface Low tide terrace BEACH Berm/Backshore Beachface Low tide terrace POCKET BEACH Delta Beaches Rocky Coast Typical Puget Sound coastal landforms ( shoreforms ) (from Shipman et al. 2008)

11 NEARSHORE ECOSYSTEM PROCESSES Rocky rocky Shores shores Lagoon lagoon Nearshore Ecosystem Process Domains sediment supply and transport beach erosion and accretion CZ L-R L-R DZ Lagoon lagoon Pocket pocket Beach beach freshwater inflow tidal hydrology distributary channel migration tidal channel formation and maintenance R-L euryhaline unvegetated estuarine mixing R-L Barrier barrier Beach beach localized wind and wave inputs to shoreline River river Delta delta oligohaline transition freshwate r tidal Stream stream Delta delta L-R DZ NAP Coastal coastal Bluffs bluffs Stream stream - mouth Estuary estuary Longshore transport Drift cell processes DZ: Divergence Zone sediment delivery R-L: Right to Left sediment transport L-R: Left and Right sediment transport CZ: Convergence Zone sediment accretion/sink NAP: No Appreciable Drift Delta processes EU: euryhaline unvegetated EM: estuarine mixing OT: oligohaline transition FT: freshwater tidal

12 PSNERP Change Analysis: Geospatial Shoreline Process Units Delta Process Units Whidbey Basin example of hierarchical organization in PSNERP geographic scale units (GSU) for shoreline process units (SPU; left) and delta process units (DPU), with littoral drift cells (Drift Cell Type) components. Cross-hatching indicates overlap in SPU (in Divergence Zone and where No Appreciable Drift); stippling indicates where SPU and DPU overlap.

13 PSNERP Change Categories (Tiers)

14 PSNERP CHANGE ANALYSIS Results Categories & Display For each of the four change categories (tiers), we quantify nearshore ecosystem change and rank EFG&S impairment of nearshore ecosystem processes at four scales: 1.Comprehensive, Puget Sound-wide 2.Puget Sound (PSNERPdefined) sub-basins 3.Within process units 4.Among attributes of change within process units

15 PSNERP CHANGE ANALYSIS Whidbey Subbasin example of transitions in shoreform type (Tier 1) to Artificial shoreform (top) and from historic (left) to current (right) of different natural shoreforms (bottom). HISTORIC CURRENT

16 Puget Sound-wide Change Shoreform Transitions (Tier 1) 5091 shoreform segments; 4300 unchanged (85.8%) ~76%

17 PSNERP CHANGE ANALYSIS Historic Shoreform Change Sound-Wide * * * * * *

18 PSNERP CHANGE ANALYSIS Whidbey Sub-Basin segment illustrating examples of shoreline alterations (Tier 2) changes; other features analyzed in this tier included nearshore fill, nearshore railroads (active and abandoned), and percent change in wetland classes.

19 Puget Sound-wide Change Shoreline Alterations (Tier 2) 20

20 PSNERP CHANGE ANALYSIS Cumulative Shoreline Alterations Cumulative stressors can be identified as spatiallyexplicit hot spots of impairment

21 PSNERP CHANGE ANALYSIS Multivariate Analysis of Shoreline Alterations Groups of similarly changed PU inform distribution and extent of restoration or protection, and management measure(s), required to address strategic need

22 Scaling Observed Changes to Impairment* of Ecosystem Functions, Goods & Services (EFG&S) Shoreform Transition (Tier 1) Shoreforms are ranked by their relative ability to provide, regulate, support or enhance ecosystem functions, goods and services Shoreline Alteration, Adjacent Upland and Watershed Area Change (Tiers 2, 3, & 4) Attributes/modifications are ranked by the relative ability to reduce ecosystems ability to provide functions, goods, and services * impairment is PSNERP estimate of how and where observed changes to nearshore conditions reduces the ability of an ecosystem to provide functions, goods, and services

23 Ecosystem Functions Goods and Services (Millennium Ecosystem Assessment/World Resources Institute) Functions, goods and services that ecosystems provide to benefit human well-being and other life on Earth Provisioning: Food: crops; livestock; capture fisheries; aquaculture; wild foods Fiber: timber and other wood fiber; other fibers Biomass fuel Water (quantity) Genetic resources Biochemicals, natural medicines and pharmaceuticals Supporting: Nutrient cycling Soil formation* Food web* Photosynthesis* Sediment supply* Regulating: Air quality regulation Climate regulation: global; regional and local Water regulation (hydroperiod) Water purification and waste treatment Disease regulation Pest regulation Pollination Natural hazard regulation Cultural: Ethical value Existence values Recreation and ecotourism Education Millennium Ecosystem Assessment (MA) Ecosystems and Human Well-Being: Current State and Trends. Island Press, Washington, DC. World Resources Institute (WRI) Ecosystems and Human Well-Being: Synthesis. Millennium Ecosystem Assessment. Island Press, Washington, D.C.

24 RANKING OF EFG&S IMPAIRMENT BY NEARSHORE ECOSYSTEM CHANGE The NST individually and assigned ranks for each of the shoreform transitions (Tier 1), shoreline attribute (Tier 2), or change in adjacent upland and total watershed area characteristics (tiers 3 and 4) in terms of how changes would affect the ability of the nearshore ecosystem to provide, regulate, support or enhance human well-being in each EFG&S. EFG&S Ranks for Shoreline Alterations (Tier 2)

25 PSNERP CHANGE ANALYSIS Impairment due to Shoreline Alteration (Tier 2)

26 MAPPING SOURCES OF NEARSHORE ECOSYSTEM IMPAIRMENT Loss of delta wetlands Gain in Barrier Estuary and Barrier Lagoon Combined loss of Barrier Estuary and Closed Lagoon/Marsh Combined loss of Barrier Lagoon and Closed Lagoon/Marsh Gain in Barrier Beach and Barrier Estuary

27 MAPPING SOURCES OF NEARSHORE ECOSYSTEM IMPAIRMENT Gain of wetlands outweighs negative impact of roads Nearshore Roads, Abandoned Railroads, Wetland loss Oligohaline & Estuarine Mix

28 MAPPING SOURCES OF NEARSHORE ECOSYSTEM IMPAIRMENT Impervious surface Relatively more impervious surface and low intensity development

29 MAPPING SOURCES OF NEARSHORE ECOSYSTEM IMPAIRMENT Amount of impervious surface throughout watershed relative to other areas of sub-basin

30 Take-Home Message Framework of geospatial characterization of historic change in nearshore ecosystems that we can use to infer changes in ecosystem processes and functions, goods and services Informs spatially-explicit assessment of strategic restoration and protection needs Contributes to more sustainable restoration and protection planning and actions at all implementation scales

31 Thank You! For more information: Visit PSNERP website : Or, contact me directly: simenstd@u.washington.edu With acknowledgements to all the PSNERP team and particularly NST colleagues!