Community Ecology
Spatial dynamics of communities: landscape ecology
Outline:
1. Patch-matrix approach to organism-environment interactions
A. Assumptions of P-M
B. Problems with P-M
2. Alternative to P-M: mosaic approach
A. Focus is on amount, placement, and connectivity of landscape elements
B. Is associated with rise of landscape ecology
3. Landscape ecology
A. Scope/focus
B. History
i. Europe: origins, foci, key players
ii. North America: differences to European school, foci, key players
4. Importance of considering landscape mosaic structure in community ecology
Terms/people:
patch-matrix approach
mosaic approach
landscape ecology
Carl Troll
European vs. North American schools of thought
amount, placement, connectivity of landscape elements
"...spatial variability, or patchiness, in natural populations is a dynamically interesting quantity
rather than a statistical nuisance to be overcome..." (Schneider 1994, p. 7)
patch-matrix approach
terrestrial analog of island biogeography
problems, especially with concept of “sea” (matrix)
Habitat fragmentation and the matrix:
http://www.youtube.com/watch?v=JZwTZ-d1ZRE&desktop_uri=%2Fwatch%3Fv%3DJZwTZd1ZRE&app=desktop
The Wog Wog Experiment:
http://vimeo.com/21249067
paradigm shift  mosaic approach
amount, placement, and connectivity of landscape elements (Dunning et al. 1992,
Taylor et al. 1993)
This paradigm shift corresponds to the rise of a new field in ecology: landscape ecology ("the
study of the effects of pattern on process" - Turner 1989)
Roots in Europe, Carl Troll 1939
The European vs. North American “schools” of landscape ecology
Why considering landscape ecology & spatial effects is important to community ecology:
For much of its history, community ecology has been conducted while tacitly ignoring spatial
heterogeneity: predators perfectly mixed with prey, competitors were only affected by the
actions of their fellow competitors, niches were constant in space, etc. This is not to say that
there weren't a few ecologists who recognized the importance of including spatial variables, but
they were definitely in the minority. Yet space is inherent in community ecology:
"...the problem of pattern and scale is the central problem in ecology, unifying population
biology and ecosystem science, and marrying basic and applied ecology." (Levin 1992)
Spatial effects on communities:
- species-area relationship
- Huffaker’s (1958) work on the role spatial heterogeneity and refugia play in permitting
predator-prey coexistence
- “rescue effect” of Brown and Kodric-Brown (1977)
- “spreading of risk” (den Boer 1968)
- SLOSS
- etc.
Adopting the approaches from landscape ecology will thus make community ecology a more
realistic and rigorous science.
Next time: Communities in landscape mosaics and conservation reserve design
References:
Brown, J.H., and A. Kodric-Brown. 1977. Turnover rates in insular biogeography: effect of
immigration on extinction. Ecology 58:445-449.
Davies, K.F., B.A. Melbourne, and C.R. Margules. 2001. Effects of within- and between-patch
processes on community dynamics in a fragmentation experiment. Ecology 82:1830-1846.
den Boer, P.J. 1968. Spreading of risk and stabilization of animal numbers. Acta Biotheoretica
18:165-194.
Dunning, J.B, B.J. Danielson, and H.R. Pulliam. 1992. Ecological processes that affect
populations in complex landscapes. Oikos 65:169-175.
Forman, R.T.T. 1995. Land Mosaics: The Ecology of Landscapes and Regions. Cambridge
University Press, Cambridge, UK.
Forman, R.T.T., and M. Godron. 1986. Landscape Ecology. John Wiley & Sons, New York, NY.
Forys, E., and S.R. Humphrey. 1999. The importance of patch attributes and context to the
management and recovery of an endangered lagomorph. Landscape Ecol. 14:177-185.
Hansson, L., L. Fahrig, and G. Merriam, eds. 1995. Mosaic Landscapes and Ecological
Processes. Chapman and Hall, London, UK.
Huffaker, C.B. 1958. Experimental studies on predation: dispersion factors and predator-prey
oscillations. Hilgardia 27:343-383.
Levin, S.A. 1992. The problem of pattern and scale in ecology. Ecology 73:1943-1967.
Naveh, Z., and A. Lieberman. 1994. Landscape Ecology: Theory and Applications. SpringerVerlag, New York, NY.
Pickett, S.T.A., and M.L. Cadenasso. 1995. Landscape ecology: spatial heterogeneity in
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Schneider, D.C. 1994. Quantitative Ecology: Spatial and Temporal Scaling. Academic Press,
New York, NY.
Taylor, P.D., L. Fahrig, K. Henein, and G. Merriam. 1993. Connectivity is a vital element of
landscape structure. Oikos 68:571-573.
Turner, M.G. 1989. Landscape ecology: the effect of pattern on process. Annu. Rev. Ecol. Syst.
20:171-197.
Urban, D.L., R.V. O’Neill, and H.H. Shugart. 1987. Landscape ecology. BioScience 37:119-127.
Wiens, J.A. 1995. Landscape mosaics and ecological theory. Pp. 1-26 in: Mosaic Landscapes
and Ecological Processes (L. Hansson, L. Fahrig, and G. Merriam, eds.). Chapman and Hall,
London, UK.
Wiens, J.A, and B.T. Milne. 1989. Scaling of ‘landscapes’ in landscape ecology, or, landscape
ecology from a beetle’s perspective. Landscape Ecology 3:87-96.
Wiens, J.A., N.C. Stenseth, B. Van Horne, and R.A. Ims. 1993. Ecological mechanisms and
landscape ecology. Oikos 66:369-380.