Landscape Ecology

, Volume 19, Issue 6, pp 631–646 | Cite as

A multi-scale assessment of human and environmental constraints on forest land cover change on the Oregon (USA) coast range

  • Michael C. Wimberly
  • Janet L. Ohmann


Human modification of forest habitats is a major component of global environmental change. Even areas that remain predominantly forested may be changed considerably by human alteration of historical disturbance regimes. To better understand human influences on the abundance and pattern of forest habitats, we studied forest land cover change from 1936 to 1996 in a 25 000 km2 landscape in the Oregon (USA) Coast Range. We integrated historical forest survey data and maps from 1936 with satellite imagery and GIS data from 1996 to quantify changes in major forest cover types. Change in the total area of closed-canopy forests was relatively minor, decreasing from 68% of the landscape in 1936 to 65% in 1996. In contrast, large-conifer forests decreased from 42% in 1936 to 17% in 1996, whereas small-conifer forests increased from 21% of the landscape in 1936 to 39% in 1996. Linear regression models were used to predict changes in the proportion of large conifer forest as a function of socioeconomic and environmental variables at scales of subbasins (mean size = 1964 km2, n=13), watersheds (mean size = 302 km2, n=83), and subwatersheds (mean size = 18 km2, n=1325). The proportion of land in private ownership was the strongest predictor at all three spatial scales (partial R2 values 0.57–0.76). The amounts of variation explained by other independent variables were comparatively minor. Results corroborate the hypothesis that differing management regimes on private and public ownerships have led to different pathways of landscape change. Furthermore, these distinctive trajectories are consistent over a broad domain of spatial scales.

Disturbance Environmental heterogeneity Forest fragmentation Forest management Habitat loss Human impacts Land ownership Watersheds 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Addicott J.F., Aho J.M., Antolin M.F., Padilla D.K., Richardson J.S., and Soluk D.A. 1987. Ecological neighborhoods: Scaling environmental patterns. Oikos 49: 340–346.Google Scholar
  2. Anderson M.J. and Legendre P. 1999. An empirical comparison of permutation methods for tests of partial regression coeffi-cients in a linear model. Journal of Statistical Computation and Simulation 61: 271–303.Google Scholar
  3. Andrews H.J. and Cowlin R.W. 1940. Forest resources of the Douglas-fir region. Miscellaneous Publication No. 389, United States Department of Agriculture, Washington, D.C., USA.Google Scholar
  4. Axelsson A.-L., Ostlund L. and Hellberg E. 2002. Changes in mixed deciduous forests of boreal Sweden 1866-1999 based on interpretation of historical records. Landscape Ecology 17: 403–418.Google Scholar
  5. Black A.E., Morgan P. and Hessburg P.F. 2003. Social and biophysical correlates of change in forest landscapes of the interior Columbia Basin, USA. Ecological Applications 13: 51–67.Google Scholar
  6. Cohen W.B., Spies T.A., Alig R.J., Oetter D.R., Maiersperger T.K. and Fiorella M. 2002. Characterizing 23 years (1972-95) of stand replacement disturbance in western Oregon forests with Landsat imagery. Ecosystems 5: 122–137.Google Scholar
  7. Crow T.R., Host G.E. and Mladenoff D.J. 1999. Ownership and ecosystem as sources of spatial heterogeneity in a forested landscape, Wisconsin, USA. Landscape Ecology 14: 449–463.Google Scholar
  8. Daly C., Neilson R.P. and Phillips D.L. 1994. A statistical topographic model for mapping climatological precipitation over mountainous terrain. Journal of Applied Meteorology 33: 140–158.Google Scholar
  9. Drapeau P., Leduc A., Giroux J.-F., Savard J.-P.L., Bergeron Y. and Vickery W.L. 2000. Landscape-scale disturbances and changes in bird communities of boreal mixed-wood forests. Ecological Monographs 70: 423–444.Google Scholar
  10. Franklin J.F. and Dyrness C.T. 1973. Natural vegetation of Oregon andWashington. General Technical Report GTR-PNW-8, USDA Forest Service, Pacific Northwest Research Station, Portland, Oregon, USA.Google Scholar
  11. Hall F.G., Botkin D.B., Strebel D.E., Woods K.D. and Goetz S.J. 1991. Large-scale patterns of forest succession as determined by remote sensing. Ecology 72: 628–640.Google Scholar
  12. Halpern C.B. and Spies T.A. 1995. Plant-species diversity in natural and managed forests of the Pacific Northwest. Ecological Applications 5: 913–934.Google Scholar
  13. Hargis C.D., Bissonette J.A. and Turner D.L. 1999. The influence of forest fragmentation and landscape pattern on American martens. Journal of Applied Ecology 36: 157–172.Google Scholar
  14. Harmon M.E., Franklin J.F., Swanson F.J., Sollins P., Gregory S.V., Lattin J.D., Anderson N.H., Cline S.P., Aumen N.G., Sedell J.R., Lienkaemper G.W., Cromack K. and Cummins K.W. 1986. Ecology of coarse woody debris in temperate ecosystems. Advances in Ecological Research 15: 133–302.Google Scholar
  15. Impara P.C. 1997. Spatial and temporal patterns of fire in the forests of the central Oregon Coast Range. Oregon State University, Corvallis, Oregon, USA.Google Scholar
  16. Insightful. 2001. Splus 6 user's guide. Insightful Corporation, Seattle, Washington, USA.Google Scholar
  17. Kennedy R.S.H. and Spies T.A. in press. Forest cover changes in the Oregon Coast Range from 1939 to 1993. Forest Ecology and Management.Google Scholar
  18. Kline J.D., Moses A. and Alig R.J. 2001. Integrating urbanization into landscape-level ecological assessments. Ecosystems 4: 3–18.Google Scholar
  19. Legendre P. 1993. Spatial autocorrelation-trouble or new paradigm? Ecology 74: 1659–1673.Google Scholar
  20. Loehle C. and Li B.L. 1996. Habitat destruction and the extinction debt revisited. Ecological Applications 6: 784–789.Google Scholar
  21. Lomolino M.V. and Perault D.R. 2000. Assembly and disassembly of mammal communities in a fragmented temperate rain forest. Ecology 81: 1517–1532.Google Scholar
  22. Manly B.F. 1991. Randomization and Monte Carlo methods in biology. Chapman & Hall, London, UK.Google Scholar
  23. Martin K.J. and McComb W.C. 2002. Small mammal habitat associations at patch and landscape scales in Oregon. Forest Science 48: 255–264.Google Scholar
  24. Matlack G.R. 1994. Plant-species migration in a mixed-history forest landscape in eastern North America. Ecology 75: 1491–1502.Google Scholar
  25. McComb W.C., McGrath M.T., Spies T.A. and Vesely D. 2002. Models for mapping potential habitat at landscape scales: An example using northern spotted owls. Forest Science 48: 203–216.Google Scholar
  26. McGarigal K. and McComb W.C. 1995. Relationships between landscape structure and breeding birds in the Oregon Coast Range. Ecological Monographs 65: 235–260.Google Scholar
  27. Mladenoff D.J., White M.A., Pastor J. and Crow T.R. 1993. Comparing spatial pattern in unaltered old-growth and disturbed forest landscapes. Ecological Applications 3: 294–306.Google Scholar
  28. Nagaike T. and Kamitani T. 1999. Factors affecting changes in landscape diversity in rural areas of the Fagus crenata forest region of central Japan. Landscape and Urban Planning 43: 209–216.Google Scholar
  29. Neter J., Wasserman W. and Kutner M.H. 1989. Applied linear regression models. Irwin, Boston, Massachusetts, USA.Google Scholar
  30. Ohmann J.L. and Gregory M.J. 2002. Predictive mapping of forest composition and structure with direct gradient analysis and nearest-neighbor imputation in coastal Oregon, USA. Canadian Journal of Forest Research 32: 725–741.Google Scholar
  31. Ohmann J.L. and Spies T.A. 1998. Regional gradient analysis and spatial pattern of woody plant communities of Oregon forests. Ecological Monographs 68: 151–182.Google Scholar
  32. Olson D.H., Hagar J.C., Carey A.B., Cissel J.H. and Swanson F.J. 2001. Wildlife of westside and high montane forests. In Johnson D.H. and O'Neill T.A. (eds), Wildlife-habitat relationships in Oregon and Washington, pp. 187–212. Oregon State University Press, Corvallis, Oregon, USA.Google Scholar
  33. Pinder J.E., Rea T.E. and Funsch D.E. 1999. Deforestation, reforestation and forest fragmentation on the upper coastal plain of South Carolina and Georgia. American Midland Naturalist 142: 213–228.Google Scholar
  34. Radeloff V.C., Hammer R.B., Voss P.R., Hagen A.E., Field D.R. and Mladenoff D.J. 2001. Human demographic trends and landscape level forest management in the northwest Wisconsin Pine Barrens. Forest Science 47: 229–241.Google Scholar
  35. Radeloff V.C., Mladenoff D.J. and Boyce M.S. 2000. Effects of interacting disturbances on landscape patterns: Budworm defoliation and salvage logging. Ecological Applications 10: 233–247.Google Scholar
  36. Radeloff V.C., Mladenoff D.J., He H.S. and Boyce M.S. 1999. Forest landscape change in the northwestern Wisconsin Pine Barrens from pre-European settlement to the present. Canadian Journal of Forest Research 29: 1649–1659.Google Scholar
  37. Ripple W.J., Hershey K.T. and Anthony R.G. 2000. Historical forest patterns of Oregon's central Coast Range. Biological Conservation 93: 127–133.Google Scholar
  38. Robbins W.G. 1997. Landscapes of promise: The Oregon story 1800-1940. University of Washington Press, Seattle, Washington, USA.Google Scholar
  39. Spies T.A., Franklin J.F. and Thomas T.B. 1988. Coarse woody debris in Douglas-fir forests of western Oregon and Washington. Ecology 69: 1689–1702.Google Scholar
  40. Spies T.A., Reeves G.H., Burnett K.M., McComb W.C., Johnson K.N., Grant G., Ohmann J.L., Garman S.L. and Bettinger P. 2002. Assessing the ecological consequences of forest policies in a multi-ownership province in Oregon. In J. Liu and TaylorW.W. (eds). Integrating landscape ecology into natural resource management, pp. 179–207. Cambridge University Press, Cambridge, UK.Google Scholar
  41. Spies T.A., Ripple W.J. and Bradshaw G.A. 1994. Dynamics and pattern of a managed coniferous forest landscape in Oregon. Ecological Applications 4: 555–568.Google Scholar
  42. Stanfield B.J., Bliss J.C. and Spies T.A. 2002. Land ownership and landscape structure: A spatial analysis of sixty-six Oregon (USA) Coast Range watersheds. Landscape Ecology 17: 685–697.Google Scholar
  43. Tilman D., May R.M., Lehman C.L. and Nowak M.A. 1994. Habitat destruction and the extinction debt. Nature 371: 65–66.Google Scholar
  44. Turner M.G. and Ruscher C.L. 1988. Changes in landscape patterns in Georgia, USA. Landscape Ecology 1: 241–251.Google Scholar
  45. Turner M.G., Wear D.N. and Flamm R.O. 1996. Land ownership and land-cover change in the southern Appalachian highlands and the Olympic peninsula. Ecological Applications 6: 1150–1172.Google Scholar
  46. Verburg P.H. and Chen Y.Q. 2000. Multiscale characterization of land-use patterns in China. Ecosystems 3: 369–385.Google Scholar
  47. Vitousek P.M. 1994. Beyond global warming-ecology and global change. Ecology 75: 1861–1876.Google Scholar
  48. Vogelmann J.E. 1995. Assessment of forest fragmentation in southern New England using remote-sensing and geographic information-systems technology. Conservation Biology 9: 439–449.Google Scholar
  49. Wear D.N. and Bolstad P. 1998. Land-use changes in southern Appalachian landscapes: Spatial analysis and forecast evaluation. Ecosystems 1: 575–594.Google Scholar
  50. Wear D.N., Liu R., Foreman J.M. and Sheffield R.M. 1999. The effects of population growth on timber management and inventories in Virginia. Forest Ecology and Management 118: 107–115.Google Scholar
  51. Wear D.N., TurnerM.G. and Flamm R.O. 1996. Ecosystem management with multiple owners: Landscape dynamics in a southern Appalachian watershed. Ecological Applications 6: 1173–1188.Google Scholar
  52. White M.A. and Mladenoff D.J. 1994. Old-growth forest landscape transitions from pre-European settlement to present. Landscape Ecology 9: 191–205.Google Scholar
  53. Wiens J.A. 1989. Spatial scaling in ecology. Functional Ecology 3: 385–397.Google Scholar
  54. Wimberly M.C. 2002. Spatial simulation of historical landscape patterns in coastal forests of the Pacific Northwest. Canadian Journal of Forest Research 32: 1316–1328.Google Scholar
  55. Wimberly M.C. and Spies T.A. 2001. Influences of environment and disturbance on forest patterns in coastal Oregon watersheds. Ecology 82: 1443–1459.Google Scholar
  56. Wimberly M.C., Spies T.A., Long C.J. and Whitlock C. 2000. Simulating historical variability in the amount of old forests in the Oregon Coast Range. Conservation Biology 14: 167–180.Google Scholar
  57. With K.A. and Crist T.O. 1995. Critical thresholds in species responses to landscape structure. Ecology 76: 2446–2459.Google Scholar

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Michael C. Wimberly
    • 1
  • Janet L. Ohmann
    • 2
  1. 1.Warnell School of Forest ResourcesUniversity of GeorgiaAthensUSA (E-mail
  2. 2.Pacific Northwest Research StationUSDA Forest ServiceCorvallis

Personalised recommendations