Urban Ecosystems

, Volume 1, Issue 1, pp 21–36 | Cite as

Ecosystem processes along an urban-to-rural gradient

  • Mark J. McDonnell
  • Steward T. A. Pickett
  • Peter Groffman
  • Patrick Bohlen
  • Richard V. Pouyat
  • Wayne C. Zipperer
  • Robert W. Parmelee
  • Margaret M. Carreiro
  • Kimberly Medley


In order to understand the effect of urban development on the functioning of forest ecosystems, during the past decade we have been studying red oak stands located on similar soil along an urban-rural gradient running from New York City ro rural Litchfield County, Connecticut. This paper summarizes the results of this work. Field measurements, controlled laboratory experiments, and reciprocal transplants documented soil pollution, soil hydrophobicity, litter decomposition rates, total soil carbon, potential nitrogen mineralization, nitrification, fungal biomass, and earthworm populations in forests along the 140 × 20 km study transect. The results revealed a complex urban-rural environmental gradient. The urban forests exhibit unique ecosystem structure and function in relation to the suburban and rural forest stands these are likely linked to stresses of the urban environment such as air pollution, which has also resulted in elevated levels of heavy metals in the soil, the positive effects of the heat island phenomenon, and the presence of earthworms. The data suggest a working model to guide mechanistic work on the ecology of forests along urban-to-rural gradients, and for comparison of different metropolitan areas.

urban rural, forests gradients ecosystems 


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  1. Aber, J. D., Nadelhoffer, K. J., Steudler, P. and Melillo, J. J. (1989). Nitrogen saturation in northern forest ecosystems. Bioscience 39, 378–386.Google Scholar
  2. Agren, G. I. and Bosatta, E. (1988) Nitrogen saturation of terrestrial ecosystems. Environ.Pollut. 54, 185–197.Google Scholar
  3. Alig, R. J. and Healy, R. G. (1987) Urban and built-up land area changes in the United States: an empirical investigation of determinants. Land Econ. 63, 215–226.Google Scholar
  4. Anderson, J. M. (1988) Spatiotemporal effects of invertebrates on the soil processes. Biol.Fertil.Soils 6, 216–227.Google Scholar
  5. Anderson, J. M. and Ineson, P. (1984) Interactions between microorganisms and soil invertebrates in nutrient flux pathways of forest ecosystems. In Invertebrate-microbial interactions (J. M. Anderson, A. D. M. Rayner, and D. W. H. Walton, eds) pp. 59–88. Cambridge University Press, New York.Google Scholar
  6. Austin, M. P. (1987) Models for the analysis of species' response to environmental gradients. Vegetatio 69, 35–45.Google Scholar
  7. Baath, E. (1989) Effect of heavy metals in soil on microbial processes and populations (a review). Water Air Soil Pollut. 47, 335–379.Google Scholar
  8. Bengtsson, G. and Tranvik, L. (1989) Critical metal concentrations for forest soil invertebrates. Water Air Soil Pollut. 47, 381–417.Google Scholar
  9. Berry, J. L. (1990) Urbanization. In The earth as transformed by human action (B. L. Turner, W. C. Clark, R. W. Kates, J. F. Richards, J. T. Mathews and W. B. Meyer, eds) pp. 103–119. Cambridge University Press with Clark University, Cambridge.Google Scholar
  10. Blair, R. B. (1996) Land use and avian species diversity along an urban gradient. Ecol.Appl. 6, 506–519.Google Scholar
  11. Bocock, K. C. (1964) Changes in the amounts of dry matter, nitrogen, carbon, and energy in decomposing woodland leaf litter in relation to the activities of soil fauna. J.Ecol. 52, 273–284.Google Scholar
  12. Bohlen, P., Pouyat, R. V., Eviner, V. and Groffman, P. (1996) Short and long term effects of earthworms on nitrous oxide fluxes in forest soils. Suppl.Bull.Ecol.Soc.Am. 77, 43.Google Scholar
  13. Bornstein, R. D. (1968) Observations of the urban heat island effect in New York City. J.Appl.Meterol. 7, 575–582.Google Scholar
  14. Botkin, D. (1990) Discordant Harmonies. Oxford University Press, New York.Google Scholar
  15. Bourne, L. S. and Simmons, J. W. (1982) Defining the area of interest: definition of the city, metropolitan areas and extended urban regions. In Internal structure of the city (L. S. Bourne, ed) pp. 57–72. Oxford University Press, New York.Google Scholar
  16. Broughton, J. G., Fisher, D. W., Isachsen, Y. W. and Richard L. V. (1966) Geology of New York: a short account. The University of New York, The State Education Department and New York State Museum Sci.Ser.Educ.Leaflet No. 20.Google Scholar
  17. Brown, J. and Roughgarden, J. (1989). US ecologists address global change. Trends Ecol.Evol. 4, 255–256.Google Scholar
  18. Cairns, J. (1987) Disturbed ecosystems as opportunities for research in restoration ecology. In Restoration ecology: a synthetic approach to ecological research (W. R. Jordan, III, M. E. Gilpin and J. D. Aber, eds) pp. 307–320. Cambridge University Press, Cambridge, England.Google Scholar
  19. Cairns, J. (1988) Restoration ecology: the new frontier. In Rehabilitating damaged ecosystems (J. Cairns, Jr., ed) pp. 2–11, Vol. I. CRC Press, Inc., Boca Raton, Florida.Google Scholar
  20. Choudhury, D. (1988) Herbivore induced changes in leaf-litter resource quality: a neglected aspect of herbivores in ecosystem nutrient dynamics. Oikos 51, 389–393.Google Scholar
  21. Coleman, D. C. (1986) The role of microfloral and faunal interactions in affecting soil processes. In Microfloral and faunal interaction in natural and agro-ecosystems (M. J. Mitchell and J. P. Nakas, eds) pp. 317–348. Nijhoff/ Junk, Dordrecht, The Netherlands.Google Scholar
  22. Dash, M. C. and Patra, U. C. (1979) Wormcast production and nitrogen contribution to soil by a tropical earthworm population from a grassland site in Orissa, India. Rev.Ecol.Biol.Sol. 16, 79–83.Google Scholar
  23. Dickinson, R. E. (1966) The process of urbanization. In Future environments of North America (F. F. Darling and J. P. Milton, ed) pp. 463–478. Natural History Press, Garden City, New York.Google Scholar
  24. Douglas, I. (1994) Human settlements. In Changes in land use and land cover: a global perspective (W. B. Meyer and B. L. Turner, eds) pp. 149–169. Cambridge University Press, Cambridge.Google Scholar
  25. Facelli, J. and Pickett, S. T. A. (1990) The dynamics of litter. Bot.Rev. 57, 2–32.Google Scholar
  26. Findlay, S. E. G. and Jones, C. J. (1990) Exposure of cottonwood plants to ozone alters subsequent leaf decomposition. Oecologia 82, 248–250.Google Scholar
  27. Forman, R. T. T. and Godron, M. (1986) Landscape Ecology. Wiley and Sons, Inc., New York.Google Scholar
  28. Fox, R. (1987) Population Images. United Nations Fund for Population Activities, New York.Google Scholar
  29. Freedman, B. (1989) Environmental Ecology: The Impacts of Pollution and Other Stresses on Ecosystem Structure and Function. Academic Press, San Diego, California.Google Scholar
  30. Freedman, B. and Hutchinson, T. C. (1979) Effects of smelter pollutants on forest leaf litter decomposition near a nickelcopper smelter at Sudbury, Ontario. Can.J.Bot. 58, 1722–1736.Google Scholar
  31. Frey, H. T. (1984) Expansion of Urban Area in the United States: 1960–1980. U.S.D.A. Economic Research Service Staff ReportNo. AGES830615. Washington, D.C.Google Scholar
  32. Friedland, A. J., Johnson, A. H. and Siccama, T. C. (1984) Trace metal content of the forest floor in the Green Mountains of Vermont: spatial and temporal patterns. Water Air Soil Pollut. 21, 161–170.Google Scholar
  33. Godron, M. and Forman, R. T. T. (1983) Landscape modification and changing ecological characteristics. In Disturbance and ecosystems, components and response (H. A. Mooney and M. Godron, eds) pp. 12–28. SpringerVerlag, New York.Google Scholar
  34. Goldman, M. B., Groffman, P. M., Pouyat, R. V., McDonnell, M. J. and Pickett, S. T. A. (1995) Methane uptake and nitrogen availability in forest soils along an urban to rural gradient. Soil Biol.Biochem. 27, 281–286.Google Scholar
  35. Gonick, W. N., Shearin, A. E. and Hill, D. E. (1970) Soil Survey of Litchfield County, Connecticut. U.S.D.A. Soil Conservation Service, U.S. Government Printing Office, Washington, D.C.Google Scholar
  36. Goudie, A. (1990) The Human Impact on the Natural Environment. 388 pp. The MIT Press, Cambridge, Massachusetts.Google Scholar
  37. Gradedel, T. E. and Crutzen, P. J. (1989) The changing atmosphere. Sci.Am. 261, 58–68.Google Scholar
  38. Groffman, P. M., Pouyat, R. V., McDonnell, M. J., Pickett, S. T. A. and Zipperer, W. C. (1995) Carbon pools and trace gas fluxed in urban forest soils. In Advances in soil science, soil management and greenhouse effect (R. Lat, J. Kimble, E. Levine and B. A. Steward, eds) pp. 147–158. CRC Press, Inc., Boca Raton, Florida.Google Scholar
  39. Gupta, A. (1995) Heavy metal accumulation by three species of mosses in Shillong, North-Eastern India. Water Air Soil Pollut. 82, 751–756.Google Scholar
  40. Haggett, P., Cliff, A. D. and Frey, A. (1977) Locational Analysis in Human Geography. (2nd ed.) John Wiley and Sons, New York.Google Scholar
  41. Haub, C. and Kent, M. M. (1989) 1989 World Population Data Sheet. Population Reference Bureau, Inc., Washington D.C.Google Scholar
  42. Hendrix, P. F., Parmelee, R. W., Crossley, D. A., Jr., Coleman, D. C., Odum, E. P. and Groffman, P. M. (1986) Detritus food webs in conventional and no-tillage agroecosystems. Bioscience 36, 374–380.Google Scholar
  43. Hill, D. E., Sauter, E. H. and Gonick, W. N. (1980) Soils of Connecticut. Connecticut Agric. Exp. Station Bull. No. 787.Google Scholar
  44. Hutton, M. (1984) Impact of airborne metal I contamination on a deciduous woodland system. In Effects of pollutants at the ecosystem level (P. J. Sheehan, ed) pp. 365–376. John Wiley and Sons, New York.Google Scholar
  45. James, S. W. and Seastedt, T. R. (1986) Nitrogen mineralization by native and introduced earthworms: effects on big bluestem growth. Ecology 67, 1094–1097.Google Scholar
  46. Johnson, D. W., Van Miegroet, H., Lindberg, S. E., Todd, D. E. and Harison, R. B. (1991) Nutrient cycling in red spruce forests of the Great Smoky Mountains. Can.J.For.Res. 21, 769–787.Google Scholar
  47. Jokimaki, J., and Suhonen, J. (1993) Effects of urbanization on the breeding bird species richness in Finland—a biogeographical comparison. Ornis Fenn. 70, 71–77.Google Scholar
  48. Keddy, P. A. (1989) Competition. Chapman and Hall, New York.Google Scholar
  49. Kostel-Hughes, F. (1995) The role of soil seed banks and leaf litter in the regeneration of native and exotic tree species in urban forests. PhD. Thesis Fordham University, Bronx, New York.Google Scholar
  50. Kostel-Hughes, F., Young, T. P., Carreiro, M. M. and Wehr, J. D. (1996) Experimental effects of urban and rural forest leaf litter on germination and seedling growth of native and exotic Northeastern tree species. Society for Ecological Restoration, 1996 International Conference, Paved to Protected: Restoration in the Urban/Rural Context. June 17–22, 1996, p. 67.Google Scholar
  51. Lavelle, P. I. (1988) Earthworm activities and the soil system. Biol.Fertil.Soils 6, 237–251.Google Scholar
  52. Lee, K. E. (1982) The influence of earthworms and termites on soil nitrogen cycling. In New trends in soil biology: proceedings of the VIII international colloquium of soil zoology (P. Lebrun, ed) pp. 110–125. Imprimeur DieuBrichart Louvain-la-Neuve, Belgium.Google Scholar
  53. Lee, K. E. (1985) Earthworms: Their Ecology and Relationships with Soils and Landuse. Academic Press, Sydney, Australia.Google Scholar
  54. Lepp, N. W., ed. (1981) Effect of Heavy Metal Pollution on Plants.Vol 1.Effects of Trace Metals on Plant Function. Applied Science Publishers, Englewood, New Jersey.Google Scholar
  55. Ludwig, D. F. (1989) Anthropic ecosystems. Bull.Ecol.Soc.Am. 70, 12–14.Google Scholar
  56. Marinssen, J. C. Y. and Bok, J. (1988) Earthworm-amemded soil structure: its influence on Collembola populations in grassland. Pedobiologia 32, 243–252.Google Scholar
  57. McColl, J. G. and Bush, D. S. 1978. Precipitation and throughfall chemistry in the San Francisco bay area. J.Environ.Qual. 7, 352–357.Google Scholar
  58. McDonnell, M. J. (1988) The challenge of preserving urban natural areas: a forest for New York. J.Am.Assoc.Bot.Gard.Arbor. 3, 28–31.Google Scholar
  59. McDonnell, M. J. and Pickett, S. T. A. (1990) The study of ecosystem structure and function along urban-rural gradients: an unexploited opportunity for ecology. Ecology 71, 1231–1237.Google Scholar
  60. McDonnell, M. J., Pickett, S. T. A. and Pouyat, R. V. (1993) The application of the ecological gradient paradigm to the study of urban effects. In Humans as components of ecosystems: subtle human effects and the ecology of populated areas (M. J. McDonnell and S. T. A. Pickett, eds) pp. 175–189. SpringerVerlag, New York.Google Scholar
  61. McDonnell, M. J. and Roy, E. A. (1996) Vegetation dynamics of a remnant hardwoods-hemlock forest in New York City. Suppl.Bull.Ecol.Soc.Am. 77, 294.Google Scholar
  62. McDonnell, M. J., Rudnicky, J. L., Koch, J. M. and Roy, E. A. (1990) Permanent Forest Reference Plot System: Pelham Bay Park and Van Cortlandt Park, Bronx, New York. Vol. 3. Vegetation Analysis and Description. Report to the New York City Department of Parks and Recreation. 50 pp.Google Scholar
  63. McNulty, S. G., Aber, J. D., McLellan, T. M. and Katt, S. M. (1990) Nitrogen cycling in high elevation forests of the northeastern U.S. in relation to nitrogen deposition. Ambio 19, 38–40.Google Scholar
  64. Medley, K. E., McDonnell, M. J. and Pickett, S. T. A. (1995) Human influences on forest-landscape structure along an urban-to-rural gradient. Prof.Geogr. 47, 159–168.Google Scholar
  65. Monk, C. D. and Day, F. P. (1988) Biomass primary production, and selected nutrient budget for an undisturbed hardwood watershed. In Forest hydrology and ecology at Coweeta (W. T. Swank and D. A. Crossley, Jr., eds) pp. 151–161. SpringerVerlag, New York.Google Scholar
  66. National Oceanic and Atmospheric Administration. (1985) Climates of the States, Vol 2: New York-Wyoming 3rd edition. Gale Research Company, Detroit, Michigan.Google Scholar
  67. New York State Department of Environmental Conservation. (1989) Air Quality Report, Ambient Air Monitoring System, Annual 1988. Division of Air Resources. 199 pp.Google Scholar
  68. Nihlgard, B. (1985) The ammonium hypothesis—an additional explanation to the forest dieback in Europe. Ambio 14, 2–8.Google Scholar
  69. Parle, J. N. (1963) Microorganisms in the intestines of earthworms. J.Gen.Microbiol. 31, 1–11.Google Scholar
  70. Parmelee, R. W., Beare, M. H., Cheng, W., Hendrix, P. F., Rider, S. J., Crossley, D. A., Jr. and Coleman, D. C. (1990) Earthworms and enchytraeids in conventional and no-tillage agroecosystems: a biocide approach to assess their role inorganic matter breakdown. Biol.Fertil.Soils 10, 1–10.Google Scholar
  71. Parmelee, R. W. and Crossley, D. A., Jr. (1988) Earthworm production and role in the nitrogen cycle of a no-tillage agroecosystem on the Georgia Piedmont. Pedobiologia 32, 353–361.Google Scholar
  72. Peet, R. K. and Loucks, O. L. (1977) A gradient analysis of southern Wisconsin forests. Ecology 58, 485–499.Google Scholar
  73. Penner, J. E. (1994) Atmospheric chemistry and air quality. In Changes in land use and land cover, a global perspective (W. B. Meyer and B. L. Turner, eds) pp. 175–209. Cambridge University Press, Cambridge.Google Scholar
  74. Pickett, S. T. A. and Bazzaz, F. A. (1976) Divergence of two co-occurring succession annuals on a soil moisture gradient. Ecology 57, 169–176.Google Scholar
  75. Pouyat, R. V. (1992) Soil characteristics and litter dynamics in mixed deciduous forests along an urban-rural gradient. Doctoral Dissertation. Rutgers University, New Brunswick, New Jersey.Google Scholar
  76. Pouyat, R. V., Bohlen, P., Eviner, V., Carreiro, M. M. and Groffman, P. M. (1996) Short and long term effects of earthworms on N dynamics in forest soils. Suppl.Bull.Ecol.Soc.Am. 77, 359.Google Scholar
  77. Pouyat, R. V. and McDonnell, M. J. (1991) Heavy metal accumulation in forest soils along an urban-rural gradient in southern New York, USA. Water Air Soil Pollut. 57–58, 797–807.Google Scholar
  78. Pouyat, R. V., McDonnell, M. J. and Pickett, S. T. A. (1995) Soil characteristics in oak stands along an urban-rural land use gradient. J.Environ.Qual. 24, 516–526.Google Scholar
  79. Pouyat, R. V., McDonnell, M. J. and Picket, S. T. A. (1996) Litter and nitrogen dynamics in oak stands along an urban-rural gradient. Urban Ecosyst. (in press).Google Scholar
  80. Pouyat, R. V., McDonnell, M. J., Pickett, S. T. A., Groffman, P. M., Carreiro, M. M., Parmelee, R. W., Medley, K. E. and Zipperer, W. C. (1994b) Carbon and nitrogen dynamics in oak stands along an urban-rural gradient. In Carbon forms and functions in forest soils (J. M. Kelly and W. W. McFee, eds) pp. 569–587. Soil Science Society of America, Madison, Wisconsin.Google Scholar
  81. Pouyat, R. V., Parmelee, R. W. and Carreiro, M. M. (1994a) Environmental effects of forest soil-invertebrate and fungal densities in oak stands along an urban-rural land use gradient. Pedobiologia 38, 385–399.Google Scholar
  82. Raw, F. (1962) Studies of earthworm populations in orchards: I. leaf burial in apple orchards. Ann.Appl.Biol. 50, 389–404.Google Scholar
  83. Richards, J. F. (1990) Land transformation. In The earth as transformed by human action (B. L. Turner, W. C. Clark, R. W. Kates, J. F. Richards, J. T. Mathews and W. B. Meyer, eds) pp. 163–178. Cambridge University Press with Clark University, Cambridge.Google Scholar
  84. Rogers, P. (1994) Hydrology and water quality. In Changes in land use and land cover: a global perspective (W. B. Meyer and B. L. Turner, eds) pp. 231–257. Cambridge University Press, Cambridge.Google Scholar
  85. Roodman, D. M. (1996) Rapid urbanization continues. In Vital signs 1996 (L. Starke, ed) pp. 94–95. W. W. Norton and Company, Inc., New York.Google Scholar
  86. Rudnicky, J. L. and McDonnell, M. J. (1989) Forty-eight years of canopy change in a hardwood-hemlock forest in New York City. Bull.Torrey Bot.Club 116, 52–64.Google Scholar
  87. Satchell, J. E. (1967) Lumbricidae. In Soil biology (A. Burges and F. Raw, eds) pp. 259–322. Academic Press, New York.Google Scholar
  88. Scheu, S. (1987) Microbial activity and nutrient dynamics in earthworm casts (Lumbricidae). Biol.Fertil.Soils 5, 230–234.Google Scholar
  89. Schuberth, C. J. (1968) The Geology of New York City Environs. Natural History Press, New York.Google Scholar
  90. Seastedt, T. R. and Crossley, D. A., Jr. (1983) Nutrients in forest litter treated with naphthalene and simulated throughfall: a field microcosm study. Soil Biol.Biochem. 15, 59–65.Google Scholar
  91. Shaw, C. and Pawluk, J. (1986) Fecal microbiology of Octoasion tyrtaeum, Aporrectodea turgida and Lumbricus terrestris and its relation to the carbon budgets of three artificial soils. Pedobiologia 29, 377–389.Google Scholar
  92. Siccama, T. G. (1974) Vegetation, soil, and climate on the Green Mountains of Vermont. Ecol.Monogr. 44, 325–349.Google Scholar
  93. Smith, W. H. (1990) Air Pollution and Forests: Interaction Between Air Contaminants and Forest Ecosystems. (2nd ed.) SpringerVerlag, New York, 618 pp.Google Scholar
  94. Soil Survey Staff (1975) Soil taxonomy: a basic system of classification for making and interpreting soil surveys. USDA-Soil Con. Serv. Sgr. Handbook 436, U.S. Govt. Printing Office, Washington D.C.Google Scholar
  95. Staaf, H. (1987) Foliage litter turnover and earthworm population in three beech forests of contrasting soil and vegetation types. Oecologia 72, 58–64.Google Scholar
  96. Stearns, F. and Montag T. (ed) (1974) The Urban Ecosystem: A Holistic Approach. Dowden, Hutchinson and Ross, Inc., Stroudsburg, Pennsylvania.Google Scholar
  97. Steinberg, D. A., Pouyat, R. V., Parmelee, R. W. and Groffman, P. M. (1996) Earthworm abundance and nitrogen mineralization rates along an urban-rural land use gradient. Soil Biol.Biochem. (in press).Google Scholar
  98. Steiner, W. A. (1994) The influence of air pollution on mossd-welling animals 2. Aquatic fauna with emphasis on nematoda and tardigrada. Rev.Suisse Zool. 101, 699–724.Google Scholar
  99. Syers, J. K. and Springett, J. A. (1984) Earthworms and soil fertility. Plant Soil 76, 93–104.Google Scholar
  100. Treshow, M. (1984) Air Pollution and Plant Life. John Wiley and Sons, New York.Google Scholar
  101. Tyler, G. (1975) Heavy metal pollution and mineralization of nitrogen in forest soils. Nature 255, 701–702.Google Scholar
  102. Tyler, G. (1978) Leaching rates of heavy metal ions in forest soils. Water Air Soil Pollut. 9, 137–148.Google Scholar
  103. United States Bureau of Census. (1980) Census user's guide. United States Department of Commerce, United States Government Printing Office, Washington, D.C.Google Scholar
  104. U.S. Geological Survey (1986) Land use and land cover digital data from 1:250,000 and 1:100,000scale maps. Data Users Guide 4. U.S. Geological Survey, Reston, Virginia.Google Scholar
  105. Van Hook, R. I. and Shults, W. D. (1977) Effects of trace contaminants from coal combustion. USERDA Publ. No. 7764. US Energy Research Development Administration, Washington, D.C. 70 pp.Google Scholar
  106. Vitousek, P. M. and Matson, P. A. (1990) Gradient analysis of ecosystems. In Comparative analysis of ecosystems: patterns, mechanisms and theories (J. J. Cole, G. M. Lovett, S. E. G. Findlay, eds) pp. 287–298. SpringerVerlag, New York.Google Scholar
  107. White, C. S. and McDonnell, M. J. (1988) Nitrogen cycling processes and soil characteristics in an urban versus rural forest. Biogeochemistry 5, 243–262.Google Scholar
  108. Whittaker, R. H. (1967) Gradient analysis of vegetation. Biol.Rev. 49, 207–264.Google Scholar
  109. Wolda, H., Marek, J., Spitzer, K. and Novak, I. (1994) Diversity and variability of leipdoptera populations in urban Brno, Czech Republic. Eur.J.Entomol. 91, 213–226.Google Scholar
  110. Yeates, G. (1981) Soil nematode populations depressed in the presence of earthworms. Pedobiologia 22, 191–195.Google Scholar

Copyright information

© Chapman and Hall 1997

Authors and Affiliations

  • Mark J. McDonnell
    • 1
  • Steward T. A. Pickett
    • 2
  • Peter Groffman
    • 2
  • Patrick Bohlen
    • 2
  • Richard V. Pouyat
    • 3
  • Wayne C. Zipperer
    • 3
  • Robert W. Parmelee
    • 4
  • Margaret M. Carreiro
    • 5
  • Kimberly Medley
    • 6
  1. 1.University of of Connecticut, Bartlett ArboretumStamfordUSA
  2. 2.Institute of Ecosystem StudiesMillbrookUSA
  3. 3.U.S.D.A. Forest-Service-NEFES, SUNY-CESFSyracuseUSA
  4. 4.Department of EntomologyOhio State UniversityColumbusUSA
  5. 5.Fordham University, The Louis Calder CenterDrawer K ArmonkUSA
  6. 6.Department of GeographyMiami UniversityOxfordUSA

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