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Creating Successful Freshwater Wetlands
Ynes S. ArochoBIO 690: Qualifying Exam
M.S. Environmental Science
http://www.westcreek.org/preserve.html
Overview
Wetland Loss
Ecosystem Services
Wetland Policy
Wetland Mitigation
Mitigation Banks
Wetland Function
Wetland Plant Development
Wetland Soil Development
Salvaged Soils
Reference Wetlands
Restoration Costs
Urban Wetlands
West Creek Reservation
Conclusions
Wetland Loss
56% of US wetlands (Dahl, 1991)
90% of Ohio wetlands(Dahl, 1991)
Over half the world’s wetlands are lost or severely degraded (Yallop and O’Connell, 2000)
Source:http://www.nwrc.usgs.gov/wdb/pub/others/wetstatus.pdf
Wetland Policy
Section 404 of the Clean Water Act Compensatory
mitigation “No Net Loss”
Regulation has three levels: Avoidance Minimization Compensation
http://onlinelibrary.wiley.com/doi/10.1111/j.1474-919X.2004.00333.x/full
Wetland Mitigation
Four options Establish a new site Restore a previously
exiting site Enhance function of
an existing site Preserve an existing
site
Mitigation ratio Type and size of
wetland destroyed determines type and size of created wetland required.
Required ≠ Actual
National Research Council Study, 2001
Purpose: evaluate wetland mitigation practice.
Plant species composition = 10 or more yrs to stabilize
Soil development = 3-30 yrs to stabilize
Plant assemblages do not replace function
Recommendation: Both plant community
structure and wetland function should be considered during mitigation.
Resulting wetland should be self-sustaining Wetland hydrology
Mitigated Wetlands in Ohio
Kettlewell,2005 101 mitigation sites 425.3 acres impacted 697.8 acres required 496.8 acres actual
(71.2% of required) Mitigation ratio 1.17:1
1.17 acre created / 1 acre destroyed http://www.ohiodnr.com/Home/wild_resourcessubhomepage/
ResearchandSurveys/WildlifePopulationStatusLandingPage/WoodDuck/tabid/19334/Default.aspx
Compliance Performance Standards
Vary among permits Vary among similar
wetland types Some too stringent or
too modest Difficult to determine
success or failure Examples: minimum #
native plants, survival of # woody species
http://andreawilliamsministries.com/what-does-success-really-mean-anyways/success-and-failure-road-sign-with-dramatic-clouds-and-sky/
Mitigated Wetlands in Illinois Matthews and
Endress, 2008 76 mitigation sites
113.6 hectares proposed
31.7 hectares deficit Applied performance
standards 8 failed all goals 45 met some goals 23 met all goals
Matthews and Endress, 2008
Mitigation Banks
Large wetland area Sell mitigation credits
(hectares of wetlands) to parties required to mitigate.
2005 estimates: 363 active banks 75 sold out banks 169 proposed banks 78% are for-profit
http://www.dot.state.oh.us/DIVISIONS/TRANSSYSDEV/ENVIRONMENT/ECOLOGICAL_RESOURCES_PERMITS/MITIGATIONINVENTORY/Pages/default.aspx
ODOT Mitigation Inventory
Wetland Function Federal standards
measure vegetation for 5 yrs.
Do not measure: Biotic integrity Nutrient cycling Trophic dynamics Hydrology Soils Fauna Microbial characteristics
Recommendation:Mitsch and Wilson, 1996 and
Zedler, 2004
Require longer monitoring periods
Plant characteristics alone are not adequate measurements of wetland function
Wetland Plant Development Mitsch et al. 2005 Planted vs. unplanted Vegetation cover vs.
plant diversity Pulsing experiment:
Planted wetland: plant cover from 73% to 62%.
Unplanted wetland: plant cover from 74% to 38%.
Mitsch et al., 2005
Wetland Soil Development Mitsch et al. 2005 Prior to creation: no
hydric wetland soils 2 yrs later:
78% of samples
(0-8 cm) 24% of samples
(9-16 cm) 10 yrs later: 94% of
samples in both layers. Supports NRC, 2001
Mitsch et al., 2005
Salvaged Soils
McKinstry and Anderson, 2005
Soil from donor wetland used to create new wetland
Increased plant composition compared to control group
Combination of salvaged soils and plantings?
http://www.pacificexc.com/projects/main.php?g2_itemId=468
Reference Wetlands Campbell et al., 2002 Compared soils and
plants Soil chroma, defines
soils; low = wetland; high = upland
Higher in created sites Plant species richness
lower in created sites. Higher percent of upland
plant species in created sites.
Stolt et. al., 2000 Compared wetland
topography Created sites: 40-60%
less elevation change across area
Created sites: very little microrelief
Provides habitat variety thus increasing biodiversity
Restoration Costs
Gutrich and Hitzhusen, 2004
Ecological-economic computer simulation model
Functional indicators: plant species richness, hydric soils and native plants
Prediction: 7-44 yrs to reach functional equivalency
Prediction: $5190-$309,108 lag cost above private cost
Recommendations:
1) Require a bond equal to estimated benefits provided by wetland – high restoration cost with low lag cost vs. low restoration cost with high lag cost
2) Delay issuance of drainage permit until functional equivalence is achieved in replacement – no lag costs
3) Use wetland banks – functional equivalency already established
Urban Wetlands
Obstacles: hydrology, habitat, infrastructure, pests and people
Goal: rehabilitation not restoration to their original condition
Difficult to evaluate success: criteria must reflect ecology of wetland with reality of urban context.
Source:http://www.biohabitats.com/ndg_newsite/newsletter/2010spring/article.urbecrest.php
Urban Wetland Assessment
Correct use of reference wetland
Undisturbed site Degraded sites
Success: restored site more similar to undisturbed reference site without similar response in the degraded control site.
Grayson, et al., 1999 http://office.microsoft.com/en-us/images/results.aspx?qu=grades#mt:0
Maximize Benefits of Restorations
1) Involve the public
2) Community-based initiatives
3) Facilitator (stakeholder representative)
4) Environmental education
5) Small-scale demos
6) Evaluate progress (questionnaires)
Casagrande, 1997
Source: http://office.microsoft.com/en-us/images/
Source: http://office.microsoft.com/en-us/images/
West Creek Reservation
West Creek Preservation Committee (citizen goup)
Part of Cleveland Metroparks System
Parma, Seven Hills, Brooklyn Heights and Independence
Highly urbanized area Tributary to Cuyahoga
Riverhttp://www.westcreek.org/preserve.html
West Creek Wetlands
Old municipal landfill Created and planted
in 2002 Wetland design (step-
down wetlands) Plant surveys –
increased range Usage: recreational,
educational and habitat for animals.
Source: www.maps.google.com
Photo by: Ynes Arocho
Aug 2002
http://www.westcreek.org/preserve.html
Aug 2004http://www.westcreek.org/preserve.html
May 2002Photo by: Ynes Arocho
Conclusions
Progress so far: Replace function Salvage soils Plantings Hydrology Mitigation banks Ecosystem
services
Ideas for the future: Reevaluate policy Standardize
permit requirements
Encourage use of mitigations banks
Further research on function
Further explore valuing services
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