Agroforestry Systems

, Volume 61, Issue 1–3, pp 257–268 | Cite as

Ecology of tree intercropping systems in the North temperate region: Experiences from southern Ontario, Canada

  • N.V. Thevathasan
  • A.M. Gordon


Agroforestry practices in northern latitudes, although less diverse than those in warmer regions, have unique advantages over conventional land-use systems in the region in terms of water-quality enhancement, carbon sequestration, and biodiversity conservation. Tree intercropping, especially, is a potentially promising agroforestry option in the region. Understanding the ecological interactions between trees and crops in such intercropped systems provides the basis for designing efficient systems with potential for wider applicability. With this objective, the experience from several years of research on this aspect at the University of Guelph, in southern Ontario, Canada are presented. Yields of C3 crops intercropped with trees, as well as growth of trees, did not differ from those in corresponding sole-stand (conventional) systems of crops and trees. But, soil organic carbon content and bird and insect diversity increased in the intercropped area. The abundance and distribution of earthworms were higher closer to the tree rows indicating improved soil health. The C sequestration potential in fast-growing tree (hybrid-poplar)-based intercropping systems was four times more than that reported for conventional agricultural fields in the region. Because of reduced fertilizer use and more efficient N-cycling, the tree-intercropping systems could also lead to the reduction of nitrous oxide emissions from agricultural fields by about 0.7 kg ha−1 yr−1. Marginal or degraded land that is suitable for agroforestry is estimated to be 57 million ha in Canada. Tree/crop intercropping is one agroforestry system that shows great potential for this region. We suggest that this land-management option can be placed above conventional agriculture in terms of long term-productivity and sustainability.

Agroecosystems Biodiversity Biophysical interactions Carbon sequestration Intercropping systems Sustainable agriculture 


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  1. Bezkorowajnyj P.G., Gordon A.M. and McBride R.A. 1993. The effect of cattle foot traffic on soil compaction in a silvo-pastoral system. Agroforest Syst 21: 1–10.CrossRefGoogle Scholar
  2. Brady N.C. and Weil R.R. 2002. The Nature and Properties of Soils, 13th edition. Prentice Hall, 960 pp.Google Scholar
  3. Cole C.V., Cerri C., Minami K., Mosier A., Rosengerg N. and Sauerbeck D. 1996. Agricultural options for mitigation of greenhouse gas emissions. pp. 745–771. In: Watson R.T., Zinyowera M.C. and Moss R.H. (eds), Climate Change 1995. Impacts, Adaptations and Mitigation of Climate Change: Scientific Technical Analysis. Published for the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK.Google Scholar
  4. Dixon R.K., Winjum J.K., Andrasko K.J., Lee J.J. and Schroeder P.E. 1994. Integrated land-use systems: Assessment of promising agroforest and alternative land-use practices to enhance carbon conservation and sequestration. Climate Change 27: 71–92.CrossRefGoogle Scholar
  5. Dyack B., Rollins K. and Gordon A.M. 1999. A model to calculate ex ante the threshold value of interaction effects necessary for proposed intercropping projects to be feasible to the landowner and desirable to society. Agroforest Syst 44: 197–214.CrossRefGoogle Scholar
  6. Edwards C.A. and Bohlen P.J. 1997. Biology and Ecology of Earthworms. Chapman and Hall, London, 426 pp.Google Scholar
  7. Edwards C.A. and Lofty J.R. 1977. Biology of Earthworms. Chapman and Hall, London, 333 p.p.Google Scholar
  8. García-Barrios L and Ong C.K. 2004. Ecological interactions, management lessons and design tools in tropical agroforestry systems. (This volume).Google Scholar
  9. Garrett H.E., Rietveld W.J., Fisher R.F., Kral D.M. and Viney M.K. (eds) 2000. North American Agroforestry: An Integrated Science and Practices. American Society of Agronomy, Madison, WI, USA, 402 pp.Google Scholar
  10. Gordon A.M. and Williams P.A. 1991. Intercropping of valuable hardwood tree species and agricultural crops in southern Ontario. Forest Chron 67: 200–208.Google Scholar
  11. Gordon A.M. and Newman S.M. 1997. Temperate Agroforestry Systems. CAB International, Wallingford, UK, 269 pp.Google Scholar
  12. Gordon A.M., Newman S.M. and Williams P.A. 1997. Temperate agroforestry: An overview. pp. 1–8. In: Gordon A.M. and Newman S.M. (eds), Temperate Agroforestry Systems. CAB International, Wallingford, UK. IPCC: Accessed October 17, 2003.Google Scholar
  13. Jose S., Gillespie A.R. and Pallardy S.G. 2004. Interspecific interactions in temperate agroforestry. (This volume).Google Scholar
  14. Kenney W.A. 1987. A method for estimating windbreak porosity using digitized photographic silhouettes. Agr Forestry Meteorol 39: 91–94.CrossRefGoogle Scholar
  15. Lawton J.H. 1994. What do species do in ecosystems? Oikos 71: 367–374.Google Scholar
  16. Loeffler A.E., Gordon A.M. and Gillespie T.J. 1992. Optical porosity and windspeed reduction by coniferous windbreaks in southern Ontario. Agroforest Syst 17: 119–133.CrossRefGoogle Scholar
  17. Matthews S., Pease S.M., Gordon A.M. and Williams P.A. 1993. Landowner perceptions and adoption of agroforestry in southern Ontario, Canada. Agroforest Syst 21: 159–168.CrossRefGoogle Scholar
  18. McKeague J.A. 1975. Canadian Inventory: How much land do we have? Agrologist, Autumn: 10–12.Google Scholar
  19. Montagnini F. and Nair P.K.R. 2004. Carbon sequestration: An under-exploited environmental benefit of agroforestry systems. Agroforest Syst (this volume).Google Scholar
  20. Nair P.K.R. 1993. An Introduction to Agroforestry. Kluwer Academic Publishers, The Netherlands, 499 pp.Google Scholar
  21. Ntayombya P. 1993. Effects of Robinia pseudoacacia on productivity and nitrogen nutrition of intercropped Hordeum vulgare in a agrosilvicultural system: Enhancing agroforestry's role in developing low input sustainable farming systems. Ph.D. Thesis, Department of Environmental Biology, University of Guelph, Guelph, Ontario, Canada, 411 pp.Google Scholar
  22. Ntayombya P. and Gordon A.M. 1995. Effects of black locust on productivity and nitrogen nutrition of intercropped barley. Agroforest Syst 29: 239–254.CrossRefGoogle Scholar
  23. Oenema O. 1999. Strategies for decreasing nitrous oxide emissions from agricultural sources. pp. 175–191. In: Desjardins R.L., Keng J.C. and Haugen-Kozyra K. (eds), Reducing Nitrous Oxide Emissions from Agroecosystems. International N2O workshop proceedings, March 3–5, 1999. Agriculture and Agri-Food Canada, Alberta Agriculture, Canada.Google Scholar
  24. Oelbermann M. and Gordon A.M. 2000. Quantity and quality of autumnal litterfall into a rehabilitated agricultural stream. J Environ Qual 29: 603–611.Google Scholar
  25. Oelbermann M. and Gordon A.M. 2001. Retention of leaf litter in streams from riparian plantings in southern Ontario, Canada. Agroforest Syst 53: 1–9.CrossRefGoogle Scholar
  26. O'Neill G.J. and Gordon A.M. 1994. The nitrogen filtering capability of carolina poplar in an artificial riparian zone. J Environ Qual 23: 1218–1223.CrossRefGoogle Scholar
  27. Ong C.K. and Huxley P. 1996. Tree-crop interactions: A physiological approach. CAB International, Wallingford, UK, 386 pp.Google Scholar
  28. Park J., Newman S.M. and Cousins S.H. 1994. The effects of poplar (P. trichocarpa x P. deltoids) on soil biological properties in a silvoarable system. Agroforest Syst 25: 111–118.CrossRefGoogle Scholar
  29. Price G.W. and Gordon A.M. 1999. Spatial and temporal distribution of earthworms in a temperate intercropping system in southern Ontario, Canada. Agroforest Syst 44: 141–149.CrossRefGoogle Scholar
  30. Rao M.R., Nair P.K.R. and Ong C.K. 1998. Biophysical interactions in tropical agroforestry systems. Agroforest Syst 38: 3–50.CrossRefGoogle Scholar
  31. Scheu S. 1995. Mixing of litter and soil by earthworms: effects on carbon and nitrogen dynamics-a laboratory experiment. Acta Zoologica Fennica. 196: 33–40.Google Scholar
  32. Thevathasan N.V. 1998. Nitrogen dynamics and other interactions in a tree-cereal intercropping systems in southern Ontario. Ph.D. Thesis. University of Guelph, Guelph, Ontario, Canada. 230 pp.Google Scholar
  33. Thevathasan N.V. and Gordon A.M. 1995. Moisture and fertility interactions in a potted poplar-barley intercropping. Agroforest Syst 29: 275–283.CrossRefGoogle Scholar
  34. Thevathasan N.V. and Gordon A.M. 1997. Poplar leaf biomass distribution and nitrogen dynamics in a poplar-barley intercropped system in southern Ontario, Canada. Agroforest Syst 37: 79–90.CrossRefGoogle Scholar
  35. Thevathasan N.V., Gordon A.M., Simpson J.A., Reynolds P.E., Price G. and Zhang P. 2004. Biophysical and ecological interactions in a temperate tree-based intercropping system. J Crop Improvement 11: (in press).Google Scholar
  36. Tian G. 1992. Biological Effects of Plant Residues with Contrasting Chemical Compositions on Plant and Soil Under Humid Tropical Conditions. Kluwer Academic Publishers, Dordrecht, The Netherlands, 114 pp.Google Scholar
  37. Williams P.A. and Gordon A.M. 1992. The potential of intercropping as an alternative land use system in temperate North America. Agroforest Syst 19: 253–263.CrossRefGoogle Scholar
  38. Williams P.A. and Gordon A.M. 1994. Agroforestry applications in forestry. Forest Chron 70: 143–145.Google Scholar
  39. Williams, P.A. and A.M. Gordon. 1995. Microclimate and soil moisture effects of three intercrops on the tree rows of a newly-planted intercropped plantation. Agroforest Syst 29: 285–302.CrossRefGoogle Scholar
  40. Williams P.A., Koblents H. and Gordon A.M. 1995. Bird use of an intercropped maize and old fields in southern Ontario. pp. 158–162. In: Ehrenreich J.H. and Ehrenreich D.L. (eds), Proceedings of the Fourth North American Agroforestry Conference 1995, Boise, Idaho, United States.Google Scholar
  41. Williams P.A., Gordon A.M., Garrett H.E., and Buck L. 1997. Agroforestry in North America and its role in farming systems. pp. 9–84. In: Gordon A.M. and Newman S.M. (eds), Temperate Agroforestry Systems. CAB International Press, Wallingford, UK.Google Scholar
  42. Young A. 1997. Agroforestry for Soil Management. CAB International, Wallingford, UK, 320 pp.Google Scholar

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • N.V. Thevathasan
    • 1
  • A.M. Gordon
    • 1
  1. 1.Department of Environmental BiologyUniversity of Guelph, GuelphOntarioCanada

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