Landscape Ecology

, Volume 23, Issue 10, pp 1143–1155 | Cite as

The use of gradient analysis studies in advancing our understanding of the ecology of urbanizing landscapes: current status and future directions

  • Mark J. McDonnellEmail author
  • Amy K. Hahs
Research Article


Over the past decade, the urban–rural gradient approach has been effectively used to study the ecology of cities and towns around the world. These studies have focused on understanding the distribution of plants and animals as well as ecosystem processes along gradients of urbanization that run from densely urbanized inner city to more rural exurban environments. We reviewed 300 papers investigating urbanization gradients that were published in peer-reviewed journals between 1990 and May 2007. Sixty-three percent of the papers investigated the distribution of organisms along urbanization gradients. Only five papers addressed the measures used to quantify the urbanization gradient itself. Within the papers addressing the distribution of organisms, 49% investigated the responses of birds to urbanization gradients, and <10% of the papers investigated more cryptic organisms. Most of these studies utilized a variety of broad measures of urbanization, but future advances in the field will require the development of some standardized broad measures to facilitate comparisons between cities. More specific measures of urbanization can be used to gain a mechanistic understanding of species and ecosystem responses to urbanization gradients. While the gradient approach has made a significant contribution to our understanding of the ecology of cities and towns, there is now a need to address our current knowledge gaps so that the field can reach its full potential. We present two examples of research questions that demonstrate how we can enhance our understanding of urbanization gradients, and the ecological knowledge that we can obtain from them.


Urban–rural gradients Biodiversity Landscape ecology Urbanization Characterizing urban landscapes Melbourne, Australia Auckland, New Zealand Tree species richness 



The authors wish to thank Kelly Holland for her assistance in compiling the database on studies employing the urban-rural gradient approach. Rodney van der Ree, Ben Hamilton and Lauren Keim were instrumental in collecting the vegetation data. We would also like to thank Mick McCarthy and Kirsten Parris for their assistance with the Bayesian analysis. This manuscript was improved by comments from Zoë Smith, Julia Stammers, Briony Norton, Margaret Carreiro, Nancy McIntyre, Jari Niemelä and an anonymous reviewer. The Baker Foundation provided generous support for this research.


  1. Alberti M (2008) Advances in urban ecology: integrating humans and ecological processes in urban ecosystems. Springer, New YorkGoogle Scholar
  2. Alberti M, Botsford E, Cohen A (2001) Quantifying the urban gradient: linking urban planning and ecology. In: Marzluff JM, Bowman R, Donnelly R (eds) Avian ecology and conservation in an urbanizing world. Kluwer Academic Publishers, Norwell, MA, pp 89–115Google Scholar
  3. Allen AP, O’Connor RJ (2000) Interactive effects of land use and other factors on regional bird distributions. J Biogeogr 27:889–900. doi: 10.1046/j.1365-2699.2000.00453.x CrossRefGoogle Scholar
  4. Allen TFH, Wyleto EP (1983) A hierarchical model for the complexity of plant communities. J Theor Biol 101:529–540. doi: 10.1016/0022-5193(83)90014-0 CrossRefGoogle Scholar
  5. Allen EB, Temple PJ, Bytnerowicz A, Arbaugh MJ, Sirulnik AG, Rao LE (2007) Patterns of understory diversity in mixed coniferous forests of southern California impacted by air pollution. Sci World J 7:247–263. doi: 10.1100/tsw.2007.72 Google Scholar
  6. Avondet JL, Blair RB, Berg DJ, Ebbert MA (2003) Drosophila (Diptera: Drosophilidae) response to changes in ecological parameters across an urban gradient. Environ Entomol 32:347–358CrossRefGoogle Scholar
  7. Blair RB (1996) Land use and avian species diversity along an urban gradient. Ecol Appl 6:506–519. doi: 10.2307/2269387 CrossRefGoogle Scholar
  8. Blair RB (2004) The effects of urban sprawl on birds at multiple levels of biological organization. Ecol Soc 9:2Google Scholar
  9. Blair RB, Launer AE (1997) Butterfly diversity and human land use: species assemblages along an urban gradient. Biol Conserv 80:113–125. doi: 10.1016/S0006-3207(96)00056-0 CrossRefGoogle Scholar
  10. Bowers MA, Breland B (1996) Foraging of gray squirrels on an urban-rural gradient: use of the GUD to assess anthropogenic impact. Ecol Appl 6:1135–1142. doi: 10.2307/2269597 CrossRefGoogle Scholar
  11. Burton ML, Samuelson LJ, Pan S (2005) Riparian woody plant diversity and forest structure along an urban–rural gradient. Urban Ecosyst 8:93–106. doi: 10.1007/s11252-005-1421-6 CrossRefGoogle Scholar
  12. Cadenasso ML, Pickett STA, Schwarz K (2007) Spatial heterogeneity in urban ecosystems: reconceptualizing land cover and a framework for classification. Front Ecol Environ 5:80–88. doi: 10.1890/1540-9295(2007)5[80:SHIUER]2.0.CO;2 CrossRefGoogle Scholar
  13. Carreiro MM, Howe K, Parkhurst DF, Pouyat RV (1999) Variation in quality and decomposability of red oak leaf litter along an urban–rural gradient. Biol Fertil Soils 30:258–268. doi: 10.1007/s003740050617 CrossRefGoogle Scholar
  14. Chapman KA, Reich PB (2007) Land use and habitat gradients determine bird community diversity and abundance in suburban, rural and reserve landscapes of Minnesota, USA. Biol Conserv 135:527. doi: 10.1016/j.biocon.2006.10.050 CrossRefGoogle Scholar
  15. Clergeau P, Jokimäki J, Snep R (2006) Using hierarchical levels for urban ecology. Trends Ecol Evol 21:660–661. doi: 10.1016/j.tree.2006.09.006 PubMedCrossRefGoogle Scholar
  16. Collins JP, Kinzig A, Grimm NB, Fagan WF, Hope D, Wu J et al (2000) A new urban ecology. Am Sci 88:416–425. doi: 10.1511/2000.5.416 CrossRefGoogle Scholar
  17. Cousins JR, Hope D, Gries C, Stutz JC (2003) Preliminary assessment of arbuscular mycorrhizal fungal diversity and community structure in an urban ecosystem. Mycorrhiza 13:319–326. doi: 10.1007/s00572-003-0239-4 PubMedCrossRefGoogle Scholar
  18. De Clercq EM, De Wulf R, Van Herzele A (2007) Relating spatial pattern of forest cover to accessibility. Landsc Urban Plan 80:14–22. doi: 10.1016/j.landurbplan.2006.04.007 CrossRefGoogle Scholar
  19. Dow K (2002) Social dimensions of gradients in urban ecosystems. Urban Ecosyst 4:255–275. doi: 10.1023/A:1015767231137 CrossRefGoogle Scholar
  20. Faeth SH, Warren PS, Shochat E, Marussich WA (2005) Trophic dynamics in urban communities. Bioscience 55:399–407. doi: 10.1641/0006-3568(2005)055[0399:TDIUC]2.0.CO;2 CrossRefGoogle Scholar
  21. Fraker ME, Snodgrass JW, Morgan F (2002) Differences in growth and maturation of blacknose dace (Rhinichthys atratulus) across an urban–rural gradient. Copeia 2002:1122–1127. doi: 10.1643/0045-8511(2002)002[1122:DIGAMO]2.0.CO;2 CrossRefGoogle Scholar
  22. Germaine SS, Wakeling BF (2001) Lizard species distributions and habitat occupation along an urban gradient in Tucson, Arizona, USA. Biol Conserv 97:229–237. doi: 10.1016/S0006-3207(00)00115-4 CrossRefGoogle Scholar
  23. Gilbert OL (1989) The ecology of urban habitats. Chapman and Hall, LondonGoogle Scholar
  24. Gleason HA (1926) The individualistic concept of the plant association. Bull Torrey Bot Club 53:7–26. doi: 10.2307/2479933 CrossRefGoogle Scholar
  25. Grimm NB, Grove JM, Pickett STA, Redman CA (2000) Integrated approaches to long-term studies of urban ecological systems. Bioscience 50:571–584. doi: 10.1641/0006-3568(2000)050[0571:IATLTO]2.0.CO;2 CrossRefGoogle Scholar
  26. Groffman PM, Pouyat RV, Cadenasso ML, Zipperer WC, Szlavecz K, Yesilonis ID et al (2006) Land use context and natural soil controls on plant community composition and soil nitrogen and carbon dynamics in urban and rural forests. For Ecol Manage 236:177–192. doi: 10.1016/j.foreco.2006.09.002 CrossRefGoogle Scholar
  27. Hahs AK, McDonnell MJ (2006) Selecting independent measures to quantify Melbourne’s urban–rural gradient. Landsc Urban Plan 78:435–448. doi: 10.1016/j.landurbplan.2005.12.005 CrossRefGoogle Scholar
  28. Hahs AK, McDonnell MJ (2007) Composition of the plant community in remnant patches of grassy woodland along an urban-rural gradient in Melbourne, Australia. Urban Ecosyst 10:355–377. doi: 10.1007/s11252-007-0034-7 CrossRefGoogle Scholar
  29. Hansen AJ, Knight RL, Marzluff JM, Powell S, Brown K, Gude PH et al (2005) Effects of exurban development on biodiversity: patterns mechanisms, and research needs. Ecol Appl 15:1893–1905. doi: 10.1890/05-5221 CrossRefGoogle Scholar
  30. Herzog F, Lausch A (2001) Supplementing land-use statistics with landscape metrics: some methodological considerations. Environ Monit Assess 72:37–50. doi: 10.1023/A:1011949704308 PubMedCrossRefGoogle Scholar
  31. Holland KD, McDonnell MJ, Williams NSG (2007) The potential impact of mollusk herbivory on native grasslands in Victoria, Australia. Aust Ecol 32:626–634CrossRefGoogle Scholar
  32. Hope D, Gries C, Zhu WX, Fagan WF, Redman CL, Grimm NB et al (2003) Socioeconomics drive urban plant diversity. Proc Natl Acad Sci USA 100:8788–8792. doi: 10.1073/pnas.1537557100 PubMedCrossRefGoogle Scholar
  33. Hope D, Zhu W, Gries C, Oleson J, Kaye J, Grimm N et al (2005) Spatial variation in soil inorganic nitrogen across an arid urban ecosystem. Urban Ecosyst 8:251–273. doi: 10.1007/s11252-005-3261-9 CrossRefGoogle Scholar
  34. Howe HL, Katterhagen JG, Yates J, Lehnherr M (1992) Urban–rural differences in the management of breast cancer. Cancer Causes Control 3:533–539. doi: 10.1007/BF00052750 PubMedCrossRefGoogle Scholar
  35. Jenerette GD, Wu JG, Grimm NB, Hope D (2006) Points, patches, and regions: scaling soil biogeochemical patterns in an urbanized arid ecosystem. Glob Change Biol 12:1532–1544. doi: 10.1111/j.1365-2486.2006.01182.x CrossRefGoogle Scholar
  36. Jerzak L (2001) Synurbanization of the magpie in the Palearctic. In: Marzluff JM, Bowman R, Donnelly R (eds) Avian ecology and conservation in an urbanizing world. Kluwer Academic Publishers, Norwell, Massachusetts, pp 403–425Google Scholar
  37. Kinzig AP, Grove JM (2001) Urban-suburban ecology. In: Levin SA (ed) Encyclopedia of biodiversity. Academic Press, San Diego, pp 733–745Google Scholar
  38. Koenig J, Shine R, Shea G (2001) The ecology of an Australian reptile icon: how do blue-tongued lizards (Tiliqua scincoides) survive in suburbia? Wildl Res 28:215–227. doi: 10.1071/WR00068 CrossRefGoogle Scholar
  39. Kong F, Nakagoshi N (2006) Spatial–temporal gradient analysis of urban green spaces in Jinan, China. Landsc Urban Plan 78:147–164. doi: 10.1016/j.landurbplan.2005.07.006 CrossRefGoogle Scholar
  40. Limberg KE, Schmidt RE (1990) Patterns of fish spawning in Hudson River tributaries: response to an urban gradient? Ecology 71:1238–1245. doi: 10.2307/1938260 CrossRefGoogle Scholar
  41. Lovett GM, Traynor MM, Pouyat RV, Carreiro MM, Zhu WX, Baxter JW (2000) Atmospheric deposition to oak forests along an urban–rural gradient. Environ Sci Technol 34:4294–4300. doi: 10.1021/es001077q CrossRefGoogle Scholar
  42. Luck M, Wu J (2002) A gradient analysis of urban landscape pattern: a case study from the Phoenix metropolitan region, Arizona, USA. Landsc Ecol 17:327–339. doi: 10.1023/A:1020512723753 CrossRefGoogle Scholar
  43. Luck MA, Jenerette GD, Wu JG, Grimm NB (2001) The urban funnel model and the spatially heterogeneous ecological footprint. Ecosystems 4:782–796. doi: 10.1007/s10021-001-0046-8 (NY, Print)CrossRefGoogle Scholar
  44. Marzluff JM (2001) Worldwide urbanization and its effects on birds. In: Marzluff JM, Bowman R, Donnelly R (eds) Avian ecology and conservation in an urbanizing world. Kluwer Academic Publishers, Norwell, Massachusetts, pp 19–47Google Scholar
  45. Marzluff JM (2005) Island biogeography for an urbanizing world: how extinction and colonization may determine biological diversity in human dominated landscapes. Urban Ecosyst 8:157–177. doi: 10.1007/s11252-005-4378-6 CrossRefGoogle Scholar
  46. Marzluff JM, Ewing K (2001) Restoration of fragmented landscapes for the conservation of birds: a general framework and specific recommendations for urbanizing landscapes. Restor Ecol 9:280–292. doi: 10.1046/j.1526-100x.2001.009003280.x CrossRefGoogle Scholar
  47. Marzluff JM, Bowman R, Donnelly R (2001) A historical perspective on urban bird research: trends, terms, and approaches. In: Marzluff JM, Bowman R, Donnelly R (eds) Avian ecology and conservation in an urbanizing world. Kluwer Academic Publishers, Norwell, Massachusetts, pp 1–17Google Scholar
  48. McCarthy MA (2007) Bayesian methods for ecologists. Cambridge University Press, CambridgeGoogle Scholar
  49. McDonnell MJ, Pickett STA (1990) Ecosystem structure and function along urban–rural gradients: an unexploited opportunity for ecology. Ecology 71:1232–1237. doi: 10.2307/1938259 CrossRefGoogle Scholar
  50. McDonnell MJ, Pickett STA, Pouyat RV (1993) The application of the ecological gradient paradigm to the study of urban effects. In: McDonnell MJ, Pickett STA (eds) Humans as components of ecosystems. Springer-Verlag, New York, pp 175–189Google Scholar
  51. McDonnell MJ, Pickett STA, Groffman P, Bohlen P, Pouyat RV, Zipperer WC et al (1997) Ecosystem processes along an urban-to-rural gradient. Urban Ecosyst 1:21–36. doi: 10.1023/A:1014359024275 CrossRefGoogle Scholar
  52. McIntyre NE, Knowles-Yanez K, Hope D (2000) Urban ecology as an interdisciplinary field: differences in the use of “urban” between the social and natural sciences. Urban Ecosyst 4:5–24. doi: 10.1023/A:1009540018553 CrossRefGoogle Scholar
  53. McKinney ML (2002) Urbanization, biodiversity and conservation. Bioscience 52:883–890. doi: 10.1641/0006-3568(2002)052[0883:UBAC]2.0.CO;2 CrossRefGoogle Scholar
  54. McKinney ML (2006) Urbanization as a major cause of biotic homogenization. Biol Conserv 127:247–260. doi: 10.1016/j.biocon.2005.09.005 CrossRefGoogle Scholar
  55. Natuhara Y, Imai C (1999) Prediction of species richness of breeding birds by landscape-level factors of urban woods in Osaka Prefecture, Japan. Biodivers Conserv 8:239–253. doi: 10.1023/A:1008869410668 CrossRefGoogle Scholar
  56. Niemelä J (1999) Is there a need for a theory of urban ecology? Urban Ecosyst 3:57–65. doi: 10.1023/A:1009595932440 CrossRefGoogle Scholar
  57. Niemelä J, Kotze DJ, Venn S, Penev L, Stoyanov I, Spence J et al (2002) Carabid beetle assemblages (Coleoptera, Carabidae) across urban–rural gradients: an international comparison. Landsc Ecol 17:387–401. doi: 10.1023/A:1021270121630 CrossRefGoogle Scholar
  58. Odell EA, Knight RL (2001) Songbird and medium-sized mammal communities associated with exurban development in Pitkin County, Colorado. Conserv Biol 15:1143–1150. doi: 10.1046/j.1523-1739.2001.0150041143.x CrossRefGoogle Scholar
  59. Ourso RT, Frenzel SA (2003) Identification of linear and threshold responses in streams along a gradient of urbanization in Anchorage, Alaska. Hydrobiologia 501:117–131. doi: 10.1023/A:1026211808745 CrossRefGoogle Scholar
  60. Parris KM (2006) Urban amphibian assemblages as metacommunities. J Anim Ecol 75:757–764. doi: 10.1111/j.1365-2656.2006.01096.x PubMedCrossRefGoogle Scholar
  61. Pickett STA, Cadenasso ML (2006) Advancing urban ecological studies: frameworks, concepts, and results from the Baltimore ecosystem study. Aust Ecol 31:114–125. doi: 10.1111/j.1442-9993.2006.01586.x CrossRefGoogle Scholar
  62. Pickett STA, Cadenasso ML, Grove JM, Nilon CH, Pouyat RV, Zipperer WC et al (2001) Urban ecological systems: linking terrestrial ecological, physical, and socioeconomic components of metropolitan areas. Annu Rev Ecol Syst 32:127–157. doi: 10.1146/annurev.ecolsys.32.081501.114012 CrossRefGoogle Scholar
  63. Piel F, Gilbert M, Franklin A, Gregoire JC (2005) Occurrence of Ips typographus (Col., Scolytidae) along an urbanization gradient in Brussels, Belgium. Agric For Entomol 7:161–167Google Scholar
  64. Pouyat RV, McDonnell MJ (1991) Heavy-metal accumulations in forest soils along an urban-rural gradient in southeastern New York, USA. Water Air Soil Pollut 57–58:797–807. doi: 10.1007/BF00282943 CrossRefGoogle Scholar
  65. Pouyat RV, Parmelee RW, Carreiro MM (1994) Environmental effects of forest soil-invertebrate and fungal densities in oak stands along an urban-rural land-use gradient. Pedobiologia (Jena) 38:385–399Google Scholar
  66. Sadler JP, Small EC, Fiszpan H, Telfer MG, Niemelä J (2006) Investigating environmental variation and landscape characteristics of an urban–rural gradient using woodland carabid assemblages. J Biogeogr 33:1126–1138. doi: 10.1111/j.1365-2699.2006.01476.x CrossRefGoogle Scholar
  67. Shochat E, Warren PS, Faeth SH, McIntyre NE, Hope D (2006) From patterns to emerging processes in mechanistic urban ecology. Trends Ecol Evol 21:186–191. doi: 10.1016/j.tree.2005.11.019 PubMedCrossRefGoogle Scholar
  68. Spiegelhalter DJ, Best NG, Carlin BP, van der Linde A (2002) Bayesian measures of model complexity and fit. J R Stat Soc B 64:583–639. doi: 10.1111/1467-9868.00353 CrossRefGoogle Scholar
  69. Steinberg DA, Pouyat RV, Parmelee RW, Groffman PM (1997) Earthworm abundance and nitrogen mineralization rates along an urban–rural land use gradient. Soil Biol Biochem 29:427–430. doi: 10.1016/S0038-0717(96)00043-0 CrossRefGoogle Scholar
  70. Sukopp H (1998) Urban ecology: scientific and practical aspects. In: Breuste J, Feldmann H, Uhlmann O (eds) Urban ecology. Springer-Verlag, Berlin, pp 3–16Google Scholar
  71. Szlavecz K, Placella SA, Pouyat RV, Groffman PM, Csuzdi C, Yesilonis I (2006) Invasive earthworm species and nitrogen cycling in remnant forest patches. Appl Soil Ecol 32:54–62. doi: 10.1016/j.apsoil.2005.01.006 CrossRefGoogle Scholar
  72. ter Braak CJF, Prentice IC (1988) A theory of gradient analysis. Adv Ecol Res 18:271–317. doi: 10.1016/S0065-2504(08)60183-X CrossRefGoogle Scholar
  73. Theobald DM (2004) Placing exurban land-use change in a human modification framework. Front Ecol Environ 2:139–144CrossRefGoogle Scholar
  74. Vilisics F, Elek Z, Lövei GL, Hornung E (2007) Composition of terrestrial isopod assemblages along an urbanisation gradient in Denmark. Pedobiologia (Jena) 51:45–53. doi: 10.1016/j.pedobi.2006.12.004 CrossRefGoogle Scholar
  75. Walsh CJ (2006) Biological indicators of stream health using macroinvertebrate assemblage composition: a comparison of sensitivity to an urban gradient. Mar Freshw Res 57:37–47. doi: 10.1071/MF05041 CrossRefGoogle Scholar
  76. Weeks JR, Larson D, Rashed T (2003) Contrast or continuum? The creation and application of an urban gradient index using remotely sensed imagery and GIS. Paper presented at the annual meeting of the population association of America, Minneapolis, pp 1–44Google Scholar
  77. Whittaker RH (1967) Gradient analysis of vegetation. Biol Rev Cambr Philos Soc 49:207–264. doi: 10.1111/j.1469-185X.1967.tb01419.x CrossRefGoogle Scholar
  78. Williams NSG, Morgan JW, McDonnell MJ, McCarthy MA (2005) Plant traits and local extinctions in natural grasslands along an urban-rural gradient. J Ecol 93:1203–1213. doi: 10.1111/j.1365-2745.2005.01039.x CrossRefGoogle Scholar
  79. Wu J (2004) Effects of changing scale on landscape pattern analysis: scaling relations. Landsc Ecol 19:125–138. doi: 10.1023/ CrossRefGoogle Scholar
  80. Zhu WX, Carreiro MA (2004) Temporal and spatial variations in nitrogen transformations in deciduous forest ecosystems along an urban–rural gradient. Soil Biol Biochem 36:267–278. doi: 10.1016/j.soilbio.2003.09.013 CrossRefGoogle Scholar
  81. Zipperer WC, Wu JG, Pouyat RV, Pickett STA (2000) The application of ecological principles to urban and urbanizing landscapes. Ecol Appl 10:685–688. doi: 10.1890/1051-0761(2000)010[0685:TAOEPT]2.0.CO;2 CrossRefGoogle Scholar
  82. Ziska LH, George K (2007) Establishment and persistence of common ragweed (Ambrosia artemisiifolia L.) in disturbed soil as a function of an urban–rural macro-environment. Glob Change Biol 13:266–274. doi: 10.1111/j.1365-2486.2006.01264.x CrossRefGoogle Scholar

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© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.Australian Research Centre for Urban Ecology, Royal Botanic Gardens Melbourne, c/o School of BotanyUniversity of MelbourneMelbourneAustralia

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