Download Ecoregion Mapping

Ecoregion Mapping
ENSC502 January 10, 2006
What’s an ecoregion?
• Must have something in common
• More in common within the same region
than between a region and others
• Q: geographically contiguous?
ENSC502 January 10, 2006
What do we want to use
ecoregions for?
• Protected area designation
• Applying norms and standards like
building codes
• Capability to support some human activity
• Flow modelling, e.g. carbon cycle
• Agricultural equivalency or ability to
support a given crop
ENSC502 January 10, 2006
How big is an ecoregion?
• “Region” is a generic term
• Hierarchical models allow subdivisions
depending on the scale you’re interested
in
ENSC502 January 10, 2006
What can we use to define them?
• Usually, “permanent” features such as
climate, natural plants
• How do we cope with climate and plant
change?
• What about degree of human
development?
• Some use taxonomic systems
ENSC502 January 10, 2006
Basic idea of why ecoregions exist
• Organisms adapt and co-evolve to fit their
conditions
• Each organism or community spreads as
far as conditions allow them to do
– May be external conditions or competition
• Genetically unrelated organisms may fit
into same niche, so ecoregions not related
to taxonomy
ENSC502 January 10, 2006
World Wildlife/National Geographic
• Use terms derived from taxonomic regions
• Originally served to figure out migration
and colonization patterns of plants and
animals
• “Palearctic”, “Afrotropical” etc.
• See
http://www.nationalgeographic.com/wildwo
rld/terrestrial.html (sorry, their map server
is down for January!)
ENSC502 January 10, 2006
Ecoregions as domains
• Idea that climate is the major controlling
factor to organism location
ENSC502 January 10, 2006
Polar domain
• Polar: icecap, tundra, subarctic, each
mountainous or not
• Basis of divisions: plant development in
summer
– How well can plants use what energy is
available?
• Annual energy range greater than daily
energy range
• Dry, most ppn in summer
ENSC502 January 10, 2006
Polar plants
• Tundra (grass, sedge, lichen, willow
shrubs)
• Lichen-birch woodlands
• Needleleaf forest
ENSC502 January 10, 2006
Humid temperate domain
•
•
•
•
•
•
•
•
Subtropical
Hot continental
Warm continental
Marine
Prairie
Mediterranean
Basis: importance of winter frost for plants
Strong seasonality
ENSC502 January 10, 2006
Humid temperate plants
• Mix of broadleaf deciduous and needleleaf
evergreen
ENSC502 January 10, 2006
Humid tropical domain
•
•
•
•
Savanna
Rainforest
Monsoon
Basis of division: winter temperature and
rainfall
• Energy flux is much greater daily than
annually
ENSC502 January 10, 2006
Dry domain
•
•
•
•
•
•
Hot desert
Hot steppe
Temperate desert
Temperate steppe
Basis of divisions: rainfall seasonality
Short and mid grasses, shrubs and woodlands
locally
• Crops usually require irrigation or other water
mitigation (summerfallow, for example)
ENSC502 January 10, 2006
ENSC502 January 10, 2006
Next lower (more detailed)
mapping level
• Systems of mapping start diverging here
• Baily: US Forest Service
– Provinces depend on vegetation
macrofeatures (structure)
– Interaction of plants with microclimate,
landform, soil, fauna
– Names related to specific locations: Bering
tundra
– Mainly descriptive
ENSC502 January 10, 2006
CEC (NAFTA environmental)
• Mandate: ecology including human activity
as part of ecosystem
• Need to understand ecoregions that might
impact on sustainability of economic
activity
• Want a system expressing problems
linked to local ecosystems that might need
to be prevented, remediated.
ENSC502 January 10, 2006
CEC system continued
• Interplay of geology, landform, soil,
vegetation, climate, wildlife, water,
settlement, industry
• Mapping uses overlays of soil maps,
landform maps, veg maps, etc.: less
hierarchical
• Ecotones are left to the mapper’s
judgement
ENSC502 January 10, 2006
What is a CEC ecoregion?
• An area of land with a distinctive
combination of actually occurring
characteristics
• Abstracted mapping from reality, not a
theoretical framework
• Levels of increasing detail: I at most
general, down to IV as needed
ENSC502 January 10, 2006
CEC ecoregion titles
• Fit into “polar domain: arctic cordillera,
tundra, taiga
• Fit into humid temp domain +/-: Hudson
plains, northern forests, marine west coast
forests, Mediterranean California, etc.
– Note sometimes mainly called by climate,
other times by location, others by vegetation.
ENSC502 January 10, 2006
Environment Canada mapping
http://www.ccea.org/ecozones/intro.html
ENSC502 January 10, 2006
EnCan
• An ecozone is an area where organisms and
their physical environment endure as a system
• 15 level I zones
• Include landforms and climate
• Plants
• Wildlife
• Human activities
• Similar to CEC but more adapted to Canada
alone
ENSC502 January 10, 2006
Canadian system contd
• Hierarchical subdivision
• Ecozones, e.g. prairies
– Ecoregions, e.g. fescue grassland
• Ecodistricts, local
ENSC502 January 10, 2006
How Canadian zonation system is
used
• Reporting: soil degradation, water
contamination, similar items
• Monitoring
– Baseline ecosystem properties and changing
conditions are recorded
– Permanent sample plots set up in each ecoregion
• Locating protected sites
– One national park in each ecoregion, terrestrial and
marine is the goal
ENSC502 January 10, 2006
ENSC502 January 10, 2006
Mapping from satellite imagery
• Less reliant on permanent features, can
get instantaneous view of what is there
• Can include dynamic features
ENSC502 January 10, 2006
Satellite contd
• Major subdivision: seasonality
– Each region has similar onset of greenness,
magnitude of max vegetation density, growing
season duration
• Add overlay of terrain, land-cover
ENSC502 January 10, 2006
Satellite contd.
• “Continuous field” mapping
– Value of 0-100 for forest cover, temperature
range, etc.
– Individual users can then specify how they
want to “harden” the classification for their
needs
• Maps for specific years can highlight
changes or variability
ENSC502 January 10, 2006
Raw data to overlay
ENSC502 January 10, 2006
Seasonally-distinct classes for
1990
http://ciesin.columbia.edu/docs/005-347/005-347.html
ENSC502 January 10, 2006
AB Natural Subregions
• Similar system but tied to AB physical
properties
• AB has ppn gradient from SE to NW,
topographical gradient from W to E, and
temperature gradient from S to N
ENSC502 January 10, 2006
ENSC502 January 10, 2006
AB subregions
• Each of the natural subregions is described in
terms of ecosites
• Ecosite is a property at a location, defined as a
point on a nutrient vs. wetness gradation
• Characterized by an association of species
• Used to evaluate potential damage under
activity scenarios, or remediation prescriptions
• Not a map per se, a series of tables and
descriptions.
ENSC502 January 10, 2006
Relating satellite maps to AB
subregions
ENSC502 January 10, 2006
• The image colours are an overlay of average
seasonal vegetation density, degree of
seasonality, and greenup time for each year
• Some years correspond well to subregions,
others do not
• Provides possibility of mapping variability
ENSC502 January 10, 2006
Summary
• Ecoregions have a lot of different
terminology
• Most systems are hierarchical
• How mapping is done depends on
purpose in mind and technology/data
available
ENSC502 January 10, 2006
Summary
Defined by:
¾ Potential of long-term actual vegetation
composition as influenced by
¾Physiography
¾Substrate and soils
¾Climate: temperature and precipitation means
and extremes
¾ Sometimes includes degree and type of human
alteration
ENSC502 January 10, 2006
Summary
Useful for:
¾ Designating protected areas
¾ Defining area over which parameters apply in
modelling
¾ Evaluating agroforestry potential
¾ Assessing potential impacts of natural or human
induced change
ENSC502 January 10, 2006