Ecological Restoration of a Brackish Marsh at Parcel 11, Estate - - PowerPoint PPT Presentation

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May 03, 2023 429 likes •676 views

Ecological Restoration of a Brackish Marsh at Parcel 11, Estate Carolina, St. John Gary Ray, Ph.D. Virgin Forest Restorations For Coral Bay Community Council Aerial of Parcel 11 Brackish Marsh Ecological Restoration Area and Environs

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Ecological Restoration of a Brackish Marsh at Parcel 11, Estate Carolina, St. John

Gary Ray, Ph.D. Virgin Forest Restorations For Coral Bay Community Council

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Aerial of Parcel 11 Brackish Marsh Ecological Restoration Area and Environs

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Ecological value of wetlands

Flood control
Groundwater replenishment
Shoreline stabilisation & storm protection
Sediment and nutrient protection
Water purification
Reservoirs of biodiversity
Wetland products
Cultural values
Recreation and tourism
Climate change mitigation and adaptation

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Human alteration to the wetland

Pre-human contact, the site may have been a

landward extension of the fringe mangrove along the immediate coastline

Broad scale cultivation (center of sugar

production for St. John) during plantation era altered the hydrologic (water flow) conditions

Recent road building and storm drainage

modifications resulted in accumulation of terrestrial sediment along the perimeter

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Ecological Restoration Defined

“The scientific study of renewing degraded,

damaged, or destroyed ecosystems by active human intervention over short time scales” ; it has a broad scope, and consists of the following strategies:

– Reintroduction of native species – Removal of exotic species – Erosion control – Hydrologic repair – Reforestation

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Main Goals of Ecological Restoration

To facilitate biological recovery of natural communities by focusing on re-introduction of a natural community’s most important natural species components and basic physical attributes, thus recovering ecosystem services. Restoration ecology may use historical or pre- human conditions as a guidepost for setting compositional structure of an ecosystem.

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Sedge community at center of brackish marsh, Parcel 11, Est. Carolina, St. John

We define the flooded area as a” Brackish Marsh” Dominant plants: Cyperus ligularis, Cyperus elegans, & Cyperus planifolius.

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Coconut grove at southern section of the restoration zone Coconuts are sandy shoreline trees from the Pacific. They tolerate salty soils wherever their root systems can penetrate deeply, but thrive in the best drained soils.

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Exotic Grazers: large mammals can thoroughly alter natural wetland communities

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Free-roaming livestock bring weed seeds from

utside the site, and stress native species on-site

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Exotic Plants: Coral vine (Antigonon leptopus)

Mexican coral vine is a noxious weed

f highly

disturbed,

pen sites on
St. John

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Exotic Species: Rain tree (Samanea saman)

This ornamental shade tree from India is prominent near the King’s Hill Rd. margin of the property.

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Coconut palms (Cocos nucifera) are of Pacific

rigin. It is not a wetland
species. It would not be

restored to any site on St. John as an ecological restoration focus. We leave the grove intact as a cultural element on the perimeter of the ecological restoration.

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Exotic Species: Soursop (Annona muricata) was likely introduced from South America, but it is well adapted to local conditions, and a favorite edible fruit.

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Native Species: Flatleaf flatsedge (Cyperus ligularis)

This sedge is a co-dominant species in the wettest portion of the brackish marsh

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Swamp flatsedge (Cyperus planifolius)

Less abundant and somewhat shorter in height than flatleaf flatsedge, but more attractive as an

rnamental species.

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Cyperus elegans

This sedge grows low to the ground in soils frequently flooded; it is abundant in the brackish marsh.

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Fenceline along west boundary of the wetland restoration

site. Land to the right

will be managed by the VI Dept of Agriculture.

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The natural sedge community is thriving. It will be enriched in areas denuded or compromised by grazing. The coconut grove on the site’s SW corner will remain. Other native woodland components will be enhanced.

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