Restoring Eelgrass to the Neponset River Estuary The Influence of Salt Marshes
Feb 23, 2016
Restoring Eelgrass to the Neponset River EstuaryThe Influence of Salt Marshes
Goals of Neponset Restoration Restore water quality Restore ecosystem heath and function Restore ecosystem services
Are oysters the answer?
0 100 200 300 400 500 600 700 80005
10152025303540
Turbidity (NTU) at Station 140
Conversion from NTU to TSS is site specific but is estimated as NTU*2.5 =TSS (mg/L)
0 100 200 300 400 500 600 7000
102030405060708090
Turbididty (NTU) at Station 89
0 100 200 300 400 500 60005
1015202530354045
Turbidity (NTU) at Station 41
0 50 100 150 200 250 300 350 400 450 5000
10203040506070
Turbidity (NTU) at Station 54
0 100 200 300 400 500 6000
102030405060
Turbidity (NTU) at Station 42
Conversion from NTU to TSS is site specific but is estimated as NTU*2.5 =TSS (mg/L)
Salt Marshes Extremely productive ecosystems Rich in marine life Important animal habitat
Nursery Sanctuary
Protect shore lines Wave action Erosion Filtering nutrients
Enhance water quality
Water Quality Improvement Sedimentation along marsh
Deposited during tidal flux and storms Rates vary among sites and depend on
particle size Rates currently unknown for Neponset
Will be enhanced with salt marsh restoration Particulate nutrients also deposited in marsh
Excess of nutrients in most coastal systems Basins general net importers of nutrients Majority of nutrients deposited in marsh
Marshes of Neponset Historic
Marshes of Neponset Present
How much marsh do we need?
These are measurements of kg/ 532 km2
In 1991 there was ~1km2 of marsh in the Neponset
For 1km -39.5 33.3 -1.1 -2.6 -0.6 9.0 -1.6 -0.4 -2.2
Nutrient Concentrations at Station 140- 1994-2011 Average
Average uM multiplied by MW
Yearly volume based on low river flow (0.6m^3/s)
Yearly volume based on high river flow (3.1m^3/s)
Ammonium 3.84(uM) 307.01 (ug/m^3) 5.81 (kg) 30.03 (kg)Nitrate+Nitrite 6.21 (uM) 385.00(ug/m^3) 7.29 (kg) 37.66 (kg)Total Dissolved N 25.71(uM) 360.17 (ug/m^3) 6.82 (kg) 35.23(kg)Particulate N 6.10(uM) 85.42(ug/m^3) 1.62(kg) 8.36 (kg)Phosphate 0.92 (uM) 87.59 (ug/m^3) 1.66 (kg) 8.57 (kg)Total Dissolved P 1.15(uM) 35.75(ug/m^3) 0.68(kg) 3.50 (kg)Particulate P 0.68 (uM) 21.10 (ug/m^3) 0.40 (kg) 2.06 (kg)Total Phosphorus 4.44(uM) 137.50(ug/m^3) 2.60 (kg) 13.45 (kg)Particulate C 47.20(uM) 566.88 (ug/m^3) 10.73(kg) 55.46 (kg)
Examples of Restoration Success
Long Island Sound- CT Sachuest Salt Marsh- RI San Francisco Bay- CA
And failures San Diego Bay- Sweetwater Marsh Several small sites in NW Europe
Debate over “success” vs. “failure” What is “restoration”? What goals need to be reached? Often cannot restore biodiversity May take longer for some factors to recover
Neponset Restoration Potential Two projects already under taken:
In 2005 dredging restored 0.06km2 of salt marsh to the Neponset Estuary
In 2011 0.2km2 were restored at Broad Meadows in Quincy
Small restoration takes a lot of effort Broad Meadows cost $5.4 million
Need to set goals and timeline Need room to expand
Needs to be suitable habitat
Marshes of Neponset Present
References Oysters and TSS:
Cerco and Noel 2007 Nutrient Data:
MWRA Neponset River Physical Measurements, collected 1989 through 2011 http://www.nae.usace.army.mil/projects/ma/bhnip/MonitoringRpt09/Summary%20Report%20Plume%20Monitoring.pdf
General Marsh Information: http://oceanservice.noaa.gov/facts/saltmarsh.html http://www.dep.state.fl.us/coastal/habitats/saltmarshes.htm http://www.dnr.sc.gov/marine/pub/seascience/dynamic.html
Water Quality and Marshes: http://
www.bainbridgewa.gov/documents/pln/2011_smp_reference3/stumpf_rp_the_process_of_sedimentation_on_the_surface_of_salt_marsh.pdf
http://geotest.tamu.edu/userfiles/167/110.pdf Maps of Marsh Loss:
http://www.mass.gov/czm/ma_estuarine_trends_1.pdf Marsh Nutrient Up-take:
http://www.bainbridgewa.gov/documents/pln/2011_smp_reference3/stumpf_rp_the_process_of_sedimentation_on_the_surface_of_salt_marsh.pdf
Current Marsh Extent: http://maps.massgis.state.ma.us/map_ol/oliver.php http://www.fws.gov/wetlands/Documents/Wetland-Status-and-Recent-Trends-for-the-Neponset-Watershed-Massachusetts-1977-1991
Restoration Information: ftp://ftp.epchc.org/EPC_Wetlands_FTP/Hart/Literature/Zedler%20and%20Callaway%201999.%20Tracking%20Wetland%20Rest..pdf http://
www.ci.bainbridge-isl.wa.us/documents/pln/2011_smp_reference3/thom_rm_adaptive_mgmt_of_coastal_ecosystem_restoration_projects.pdf
http://www.vliz.be/imisdocs/publications/114137.pdf Prior Restoration Efforts:
http://www.neponset.org/Restoration-SaltMarsh.htm http://www.mass.gov/dfwele/der/pdf/der_annual_report_2011.pdf
Cover and Land Use Maps: http://www.neponset.org/BasinPlan/Low%20Resolution/NeponsetAssessLoRes.pdf