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Enduring
Features
Definition
Enduring features are the parts of the
landscape that resist change. They are the hills and
valleys, the underlying bedrock, and the deposits
left behind by glaciers. They remain the same even
when changes in land cover and wildlife occur. They
remain the same as plants and animals move, and they
remain the same even as the climate changes.
If we liken nature to a dramatic play, we can
think of the enduring features as the stage and the
individual species as the actors. The play is the
natural community that occurs in a given place at a
given time, with all its interactions, but
regardless of the action, the stage does not change.
Four kinds of enduring features are
considered here:
bedrock - the rock that underlies upper
surface material;
surficial materials - the gravel, sand,
silt, clay, and peat that sits on top of the
bedrock;
elevation - strongly influences climate; and
topography or landforms -
mountaintops, sideslopes, and valleys.
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Importance
Enduring features are important in
conservation planning because they can serve as a surrogate,
or substitute, for information on natural communities and species
when that information is not available. Conservation
of or providing long-term stewardship for the
diversity of enduring features will in turn help
protect the diversity of natural communities and
species.
Some enduring features are helpful in
locating specific natural communities and species.
For example, we know that in
Vermont
the community called
Valley
Clayplain
Forest
is found exclusively on clay soils. And, two of its
component plant species, bur oak and barren
strawberry, are also most common on those soils.
Therefore, it is possible to examine information on
surficial geology to determine where clay deposits
exist and, with that information, predict the
potential location of a
Valley
Clayplain
Forest
and its component species. Ecologists and
conservation planners have used this technique
successfully to locate places where they should look
for significant natural communities or rare species.
The Vermont Biodiversity Project (VBP)
analyzed enduring features throughout the state and
found some interesting patterns. First, the greatest
diversity of enduring features is in the lowlands,
where calcareous rocks tend to be found and where
glacial meltwaters deposited a variety of sand,
gravel, and clay formations. Second, the greatest
amount of conserved land is found at high
elevations, away from the diversity of the lowlands.
To ensure long-term conservation of
Vermont
's biodiversity, more conservation, especially of
large landscapes, will need to occur in lowland
areas. This same analysis identified a number of
specific areas throughout the state that contain
enduring features that are not protected on any
conserved lands. These are called 'complementary
landscapes' because their conservation would
complement the enduring features that are already
protected.
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Conserved
lands versus elevation. (Source: Vermont
Biodiversity Project) |
Conservation
Goals
A town might set one or more of the following
conservation goals for enduring features:
1.
Ensure that conserved lands or lands under
long-term stewardship cover the full range of
elevations in the town.
2.
Ensure that conserved lands or lands under
long-term stewardship in the town cover all the
town's bedrock types and surficial geology types,
especially those types that are unusual in the
state.
3.
Ensure that conserved lands or lands under
long-term stewardship encompass a diversity of
landforms.
4.
Seek to conserve or provide long-term
stewardship of the complementary landscapes
identified by the Vermont Biodiversity Project (see Vermont's Natural
Heritage). Sometimes this will require cooperation
with neighboring towns.
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Obtaining
and Interpreting Information
Information Sources
See
Resources
for information on how to contact or visit the
websites of the agencies and organizations mentioned
below.
The
Vermont biodiversity Project (VBP) The
VBP did a detailed analysis of enduring features
including bedrock, surficial geology, landforms, and
elevation. Interpreting these analyses requires the
assistance of a natural resource professional. The
VBP website explains the project and these analyses,
and their report, Vermont's
Natural Heritage, provides more detailed information and
results.
Vermont
Center for Geographic Information (VCGI): This group maintains
digital data provided by the Vermont Biodiversity
Project, as well as data on geology and soils.
Vermont
Geologic Survey: The survey is part of the Vermont
Agency of Natural Resources and can provide data on
surficial and bedrock geology for your area.
Natural
Resource Conservation Service (NRCS):
The NRCS can provide information
on soils and can help you interpret that
information.
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Interpreting the Information
The
four maps below show different components of the
enduring features of Jericho. The bedrock map shows that two classes of bedrock
(as defined by the Vermont Geologic Survey for the
Vermont Biodiversity Project) occupy most of the
town. Each area of bedrock may support slightly
different vegetation types.
The map of soils shows many different types
in the town. Interpreting the soils map requires the
help of a professional, but one thing that is clear
is that there are more kinds of soils in the low
areas, where roads and development are more
prevalent.
The map of landforms is useful for locating
unusual landforms in the town, including cliffs and
steep slopes, as well as specialized landforms, such
as caves, which may harbor uncommon communities or
rare species.
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| Bedrock
Geology of Vermont |
Elevation
Zones of Vermont |
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| This
map was developed for the Vermont
Biodiversity Project from an existing map of
the bedrock geology of Vermont (Doll, 1961).
The nine classes of rock are defined by
their ecological influence rather than on
their origin or age. Generally, the rocks
that dominate much of the Green Mountains (grey
on the map) are acidic, whereas the rocks
that dominate the Champlain Valley and the
eastern part of the state (blue on the map)
are basic because they are buffered by
carbonates. (Source: Modified from Doll,
1961, by Majorie Gale and Laurence Becker,
Vermont State Geologist Office. Used with
permission.) |
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| Soils |
Landforms |
 |
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| The
soils in Jericho are diverse, and different
types are found in the valleys and uplands.
A soil map like this can help you locate
unique community types |
A
diversity of landforms can be found in
Jericho, from ridges to the stream valleys
that wind their way through town |
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Conservation
Strategies
Once information has been obtained on
enduring features and conservation goals have been
established, it is possible to develop Conservation
Strategies to help achieve those goals.
Examples of strategies specific to each goal follow.
1.
Goal: Ensure
that conserved lands or lands under long-term
stewardship cover the full range of elevations in
the town.
Strategies:
a.
Include a map of elevation zones in your town plan and emphasize
the importance
of conserving land within each elevation zone. Sample Language: In
order to ensure the conservation of a diversity of
landscapes and their associated plant and animal
communities in town, lands will be under long-term
stewardship or permanently conserved in each of the
following elevation zones: 0-800 feet; 800-1,700
feet; 1,700-2,500 feet, 2,500-3,900 feet; and above
3,900 feet. This
same language can be adapted to include the goals of
conserving bedrock types, surficial soil types, and
complementary landscapes.
b.
Compare elevation maps to conserved lands or lands under long-term
stewardship in town to see in which elevation zones
conserved lands are located. If there are elevation
zones that do not have any conserved lands or lands
under long-term stewardship, make conservation in
those zones a priority by developing plans and
programs for open space and land acquisition. c.
In addition to direct land acquisition, conservation of lands
representing specific elevation zones can also be
accomplished through the establishment of
conservation easements on common land designated in
PUDs and through TDR programs. (See Tools for more information on
PUDS and TDRs.)
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2.
Goal: Ensure
that conserved land, or land under long-term
stewardship, in the town cover all the town's
bedrock types and soil types, especially those types
that are unusual in the state.
Strategies:
a.
Include a map of bedrock types and soil types in your town plan and
emphasize the importance
of conserving land representing as many of these
bedrock and soil types as possible. Note which types
are currently underrepresented in conserved lands
and lands under long-term stewardship in town.
Example language can be adapted from
strategy
1a.
b.
Compare VBP data layer of bedrock types to conserved lands or lands
under long-term stewardship in town to see which
bedrock types are not represented. Make conservation
or stewardship of these bedrock types a priority in
your open space and land acquisition plans and
programs. Do the same with soils and surficial
geology.
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3.
Goal: Ensure
that conserved lands or lands under long-term
stewardship encompass a diversity of landforms.
Strategies:
a.
Include a topographic map of the town in your town plan and
emphasize the importance
of conserving land representing as many of the
landforms (e.g., valleys, steep slopes, gentle
slopes, flat valley floors) as possible. Note which
landforms are currently under-represented in
conserved lands or lands under long-term stewardship
in town. Language can be adapted from
strategy
1a.
b.
Compare VBP data layer of landforms to a map of conserved lands or
lands under long-term stewardship in town to see
which landforms are not represented in conserved
lands. Seek the advice of an ecologist to determine
whether those landforms are important to meeting
other conservation goals. Make conservation or
stewardship of these landforms a priority in your
open space and land acquisition plans and programs.
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4.
Goal: Seek
to conserve the complementary landscapes identified
by the
Vermont
Biodiversity Project (see
Vermont
's
Natural Heritage). Sometimes this will require
cooperation with neighboring towns.
Strategies:
a.
Include a map of the complementary landscapes that occur in your
town in the town plan and emphasize the importance
of conserving these landscapes. Examine the
complementary landscapes data layer and compare it
with conserved lands or ones under long-term
stewardship in your town and neighboring towns. Note
in your town plan which complementary landscapes are
currently not conserved or under long-term
stewardship. Language can be adapted from
strategy
1a..
b.
Make the conservation of complementary landscapes that are not
already conserved a high priority in open space,
stewardship, and land acquisition plans and
programs.
c.
Because complementary landscapes are discrete polygons, many conservation
strategies can be applied to them that are
not as suitable for the other types of enduring
features. These strategies include:
i.
Complementary landscapes in an overlay district with specific
conditions designed to protect these features from
development in and near the features; and
ii.
Allowing for PUDs in the town zoning and/or subdivision regulations
as an alternative to conventional subdivisions, and
require or provide incentives (e.g., density
bonuses) for PUD designs that cluster development
away from complementary landscapes and protect them
with conservation easements.

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