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What are corridors?
Corridors are linear patches or narrow strips -- a special kind of patches.
Examples: roads, railroads, streams/rivers, power lines, sewer lines, trails, hedge rows/windbreaks, etc.
Structure
Width, Length, Height, Shape, Contrast, Connectivity, Spatial Configuration
Corridors are dynamic
Corridors can be visually classified by types: trough corridors, wooded strips, and stream/river corridors
Function
HabitatConduitFilterSinkSource
Chasing the bear
The Great Wall in N. China
TUC use may occur on, above or below the corridor land surface. Above-ground utilities (powerlines) and underground utilities (pipelines) both have designated alignments that provide for access maintenance, landscaping, etc.
http://tuc.gov.ab.ca/
Barrier or Conduit?
Access or spread?
Roads in Chequamegon National Forest, N. WI
http://www.unl.edu/nac/windbreaks.html
http://www.gcnursery.co.uk/windbreak.html
Powerlines cause diseases through Static ElectricityNew science reveals, not radiation, but static electricity produced by powerlines interferes with the bioelectrical life process causing diseases and premature aging.
http://www.justlogiclifescience.com.au/powerlines.html
http://photos.innersource.com/page/45/31
http://www.rr-fallenflags.org/aft/aft.html
Cheatgrass was brought from Eurasia to Washington State in the 1890s. In 30 years it basically took over the W
http://www.enn.com/enn-news-archive/1999/08/081399/cheatgrass_5005.asp
Cheatgrass not only changes the fire frequency of a site, but also the fire volatility, intensity and the extent that an area is likely to burn in the future.
The combination of fires, and low nitrogen content soil may drive out the native plants. But the cheatgrass seems to thrive under these conditions.
http://www.enn.com/enn-news-archive/1999/08/081399/cheatgrass_5005.asp
Merriam & Saunders (1993)
H1: Home range sizes of all three study species would be larger in patches with a corridor than in patches w/o a corridor.
H2: Habitat generalists would more likely than habitat specialists to move between them.
H3: Individual movement distances would be affected by corridor presence.
Hypotheses: Very rare/difficult in landscape ecology
Cotton Mouse: Peromyscus gossypinus -- generalist
Old field mouse: Perromyscus polionotus -- specialist
Cotton rat: Sigmodon hispidus -- specialist
http://www.nsrl.ttu.edu/tmot1/sigmhisp.htm
Generalist
Specialists
H1: Home range sizes of all three study species would be larger in patches with a corridor than in patches w/o a corridor. not true
H2: Habitat generalists would more likely than habitat specialists to move between them. true
H3: Individual movement distances would be affected by corridor presence. not supported
Hypotheses: results