intro to restoration ecology ensc 201 – spring 2008

Intro to Restoration Ecology

ENSC 201 – Spring 2008

Why do we need restoration?• 53 % of wetlands lost nationwide• > 35 % of wetlands lost in Vermont• 50-70% loss of brackish intertidal mudflats, shores, and coastal

plains• 90 % loss of aquatic vegetation in the Chesapeake Bay• 70 % loss of riparian forests nationwide• 90 % loss of old-growth forests nationwide• 99.5 % loss of old-growth forests in the eastern U.S.• 97 % loss of pine-oak-heathland in the Lake Champlain Basin• 90 % loss of short and tall-grass prairie ecosystems nationwide• 90 % of shrub-steppe ecosystems degraded by livestock grazing

nationwide

Source: Noss et al (1995)

http://www.millenniumassessment.org//en/index.aspx

How do we prioritize areas for restoration?1. Need

• Ecological value What is the relative importance of different sites for ecosystem functioning? Examples:

1. Riparian areas2. Headwaters3. Estuaries4. Unstable uplands5. Wetland complexes6. Rare communities7. Critical habitats for particular species

• Degree of degradation?• Degree of threat more applicable for identifying areas in need of protection or

conservation

2. Opportunity

MatrixLarge Core Reserve

Buffer Terrestrial

Corridor

Terrestrial RestorationWetland Restoration

Riparian Restoration

Riparian Corridor

Matrix

Matrix Large Core Reserve

Buffer

Small Core Reserve

How does restoration fit into an overall conservation or sustainability strategy?

The Functional Landscape Approach

But what about entire ecosystems that have been severely degrade?

Answer: We need an ecosystem-level restoration approach

Restoration as The Acid Test of Ecology: Do we understand how ecosystems work well enough to reconstruct them?

It helps to have a conceptual model of the system

Ecosystem-Level Restoration

• Focus on ecological processes

Examples:

1. Soil productivity

2. Natural disturbance dynamics

3. Hydrology

4. Ecological succession!

Tiered Restoration

Site-specific restoration, remediation, mitigation, etc.

Coordinated restoration of critical areas as per an overall ecosystem management plan

Ecosystem restoration: “Bringing back an entire system or the dynamics of that system”

Large-scale

Small-scale

Atlantic Rainforest Restoration• The Atlantic rainforest

once covered 400,000 square miles

• Only 7% remains• 450 tree species per

hectare• 2.7% of world’s plant

species just in what is left• Testing innovative

funding mechanisms U.S. companies paying

for carbon sequestration• How do we restore it?

• Estimates of potential carbon credit values range from $4 to $60 (or even $110) per ton of C.

• European market currently trading for $8 to $20 per metric ton.

• Future value could increase substantially as international carbon markets develop.

Carbon Revenue

Chicago Climate Exchange

• “Voluntary ‘Cap and Trade’ greenhouse gas emission reduction and trading system.”

• One Mg Carbon trading for about $5

• Membership from the forest products industry includes:– Abitibi-Consolidated– Aracruz Celulose S.A.– Cenibra Nipo Brasiliera S.A.– International Paper– Klabin S.A.– MeadWestvaco Corp.– Stora Enso North America– Suzano Papel E Celulose SA– Temple-Inland Inc

Figure from Ingerson. 2007.

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Forest Cover Trends in New England Since European Settlement

Differences Between Pre-Settlement and Current Forests in VT and NH

Species: Abundance:Chestnut Elm

BeechSugar MapleHemlock

White PineRed Spruce

White BirchCottonwoodPin CherryRed Maple

Functionally Extirpated

Communities: Abundance:Old-Growth Forest of All Types

Floodplain Silver Maple and Sugar Maple

Rich Lowland Oak/Basswood/Ash

Forested Wetlands

Native Grasslands and Shrublands

Forest Composition

Sources: Cogbill (2000); McLachlan et al. (2000); Fuller et al. 1998; Foster 1992; Siccama (1971)

Prescribed Fire

Restoration as Experimentation

What are the elements of experimental design?

Table 1. Number of Bare Root Seedlings per Treatment Brush mats, no tubes, ½

watered periodically Brush mats and tubes, ½ watered periodically

6’ by 6’ Density 294 294 10’ by 10’ Density 106 106

FACTORIAL EXPERIMENTAL DESIGN

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