Plant Ecology

, Volume 132, Issue 1, pp 29–38

The effect of canopy disturbance on species richness in a central Himalayan oak forest

  • Ole R. Vetaas


Non-epiphytic species richness was studied in different disturbance classes within a Quercus semecarpifolia forest. Nine disturbance classes were defined according to the degree of biomass removal (lopping) and their spatial mixture. Six of these were observed in the study area. The species were divided into three functional groups: climbers, phanerophytes, and field-layer plants. The primary aim was to test if there is an elevated species richness under an intermediate disturbed canopy for (i) all vascular plants, (ii) lianas, (iii) phanerophytes and (iv) field-layer species. The richness of the different plant groups and all species were fitted against the disturbance gradient by means of Generalized Linear Models (GLM). Other environmental variables such as altitude, potential solar radiation, light intensity, canopy cover and soil parameters were also evaluated as predictors. Disturbance classes, canopy cover and light intensity were combined into a new variable, disturbance-complex, using Principal Component Analyses.

Phanerophytes did not respond to any variable. Climbers were mostly related to pH and canopy cover, and were the only group related to altitude, nitrogen and loss-on-ignition. Herbaceous plants and total species richness showed a unimodal response to disturbance classes and the complex disturbance gradient, which supports the intermediate disturbance hypothesis. Relative radiation and slope also supported a unimodal response in herbaceous plants, but disturbance had a significant additional contribution to this pattern. The most significant predictor for these two groups was pH. The responses to organic carbon and phosphorus were not significant for any of the subsets.

The results indicate that a small-scale lopping regime will enhance species richness of vascular plants; only a few species in the intermediate disturbed forest are weedy ruderals. In such a situation, the conservation policy may accept small-scale human impact as part of the forest landscape.

Biodiversity Conservation GLM Nepal Vascular plants 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Austin, M. P., Nicholls, A. O. & Margules, C. R. 1990. Measurement of the realized qualitative niche: environmental niches of five Eucalyptusspecies. Ecol. Monog. 60: 161-77.Google Scholar
  2. Abrams, M. D. 1992. Fire and the development of oak forest. Bioscience 42: 346-353.Google Scholar
  3. Black, C. A. 1965. Methods of soil analyses. II. American Society of Agronomy. Madison, Wisconsin, USA.Google Scholar
  4. Clements, F. E. 1936. Nature and structure of the climax. J. Ecol. 24: 252-284.Google Scholar
  5. Chambers, J. M. & Hastie, T. J. (eds) 1993. Statistical Models in S. Chapman & Hall, London.Google Scholar
  6. Connell. J. H. 1978. Diversity in tropical rainforest and coral reefs. Science 199: 1302-1309.Google Scholar
  7. Dobremez, J. F. 1976. Le Nepal: ecologie et biogeographie. Editions de la Recherche Scientifique, Paris.Google Scholar
  8. Ducey, M. J., Moser, W. K. & Ashton, P. M. 1996. Effect of fire intensity on understorey forest, New England, USA. Vegetatio 123: 81-90.Google Scholar
  9. Frydmann, I. & Whittaker, R. H. 1968. Forests association of southeast Lublin Province Poland. Ecology 48: 896-908.Google Scholar
  10. Goodall, D. W. 1954. Objective methods for the classification of vegetation. An essay in the use of factor analysis. Aust. J. Bot. 1: 39-63.Google Scholar
  11. Grime, J. P. 1979. Plant strategies and vegetation processes. Wiley & Sons. New York, NY.Google Scholar
  12. Gurung, V. L. 1991. Ferns - the beauty of Nepalese flora. Sahayogi Press, Kathmandu.Google Scholar
  13. Gupta, V. 1975. Upper Devonian conditions from Pulchoki Nepal Himalayas. Himalayan Geology 5: 153-173.Google Scholar
  14. Hara, H., Stearn, W. T. & Williams, H. J. 1978. An enumeration of the flowering plants of Nepal, Vol. I. British Museum Natural History. London.Google Scholar
  15. Hara, H. & Willimas, H. J. 1979. An enumeration of the flowering plants of Nepal, Vol II. British Museum Natural History, London.Google Scholar
  16. Hara, H., Chater, A. O. & Williams, H. J. 1982. An enumeration of the flowering plants of Nepal, Vol. III. British Museum Natural History, London.Google Scholar
  17. Hastie, T. J. & Pregibon, D. 1993. Generalized Linear Models. In: Chambers, J. M. & Hastie, T. J. (eds) 1993. Statistical Models in S. Chapmann & Hall, London.Google Scholar
  18. Horn, H. S. 1974. The ecology of secondary succession. Ann. Rev. Ecol. Syst. 5: 25-37.Google Scholar
  19. Huston, M. A. 1979. A general hypothesis of species diversity. The Amer Nat 113: 81-101.Google Scholar
  20. Huston, M. A. 1994. Biological diversity - The coexistence of species on changing landscapes. Cambridge University Press, Cambridge.Google Scholar
  21. Hurlbert, S. H. 1971. The nonconcept of species diversity: a critique and alternative parameters. Ecology 52: 577-586.Google Scholar
  22. Loucks, O. L. 1962. Ordinating forests communities by means of environmental scalars and phytosociological indices. Ecol. Monog.. 32: 137-166.Google Scholar
  23. Margules, C. R., Nicholls, A. O. & Austin, M. P. 1987. Diversity of Eucalyptusspecies predicted by multi-variable environmental gradient. Oecology (Berlin) 71: 229-232.Google Scholar
  24. McCullagh, P. & Nelder, J. A. 1989. Generalized linear models. 2nd ed. Chapman & Hall, London.Google Scholar
  25. Moral, R. 1972. Diversity patterns in forests vegetation of the Wenatchee Mountains, Washington. Bull. Torrey Botanical Club 99: 57-64.Google Scholar
  26. Moench, M. & Bandyopadhyay, J. 1986. People-forest interaction: a neglected parameter in himalayan forest management. Mountain Res. Devel. 6: 3–16.Google Scholar
  27. Myers, N. B. 1990. The biodiversity challenge: expanded Hot-spots analyses. Environment 10: 243-255Google Scholar
  28. Naveh, Z. & Whittaker 1979. Structural and floristic diversity of shrublands and woodlands in northern Israel and other mediterranean areas. Vegetatio 41: 171-190.Google Scholar
  29. Nelder, J. A. & Wedderburn, R. W. M. 1972. Generalized linear models. J. Roy. Stat. Soc. A. 135: 370-380.Google Scholar
  30. Oke, J. 1987. Boundary layers climate. Methuen & Co, New York.Google Scholar
  31. Odum E. P. 1971. The strategy of ecosystem development. Science 164: 262-270.Google Scholar
  32. Palmer, M. W. 1990. Spatial scale and patterns of vegetation, flora and species richness in hardwood forests of the North Carolina Piedmont. Coenoses 5: 89-96Google Scholar
  33. Palmer, M. W. 1992. The coexistence of species in fractal landscapes. The Amer. Nat. 139: 375-397.Google Scholar
  34. Palmer, M. W. 1994. Variation in species richness: towards a unification of hypotheses. Folia Geobotanica, Phytotaxa 29: 511-530.Google Scholar
  35. Palmer, M. W. & White P. S. 1994. Scale dependence and species-area relationships. Amer. Nat. 144: 717-740.Google Scholar
  36. Pausas, J. G. 1994. Species richness patterns in the understorey of Pyrenean Pinus sylvestrisforest. J. Veg. Sci. 5: 517-524.Google Scholar
  37. Peet, R. K. 1974. The measurement of species diversity. Ann Rev. Ecol. Syst. 5: 285-307.Google Scholar
  38. Peet, R. K. 1978. Forest vegetation of the Colorado Front Range: patterns of species diversity. Vegetatio 37: 65-78.Google Scholar
  39. Peet, R. K. & Christensen, N. L. 1980. Succession: a population process. Vegetatio 43: 131-140.Google Scholar
  40. Peet, R. K., Glenn-Lewin, D. C. & Walker Wolf. J. 1983. Predictions of man's impact on plant species diversity. Pp. 41-53. In: Holzner, W., Werger, M. J. A. & Ikuima, I. (eds), Man's impact on vegetation. Junk, The Hague, Amsterdam.Google Scholar
  41. Petraits, P. S., Latham, R. E. and Niesenbaum, R. A. 1989. The maintenance of species diversity by disturbance. Quart. Rev. Biol. 64: 393-418.Google Scholar
  42. Rahbek, C. 1995. The elevation gradient of species richness: a uniform pattern? Ecography 18: 200–205.Google Scholar
  43. Rao, P. Barik, S. K., Padney, H. N. & Tripathi, R. S. 1990. Community composition and tree population structure in a sub-tropical broad-leaved forest along a disturbance gradient. Vegetatio 88: 151-162.Google Scholar
  44. Rice, B. & Westoby, M. 1983. Plant species richness at the 0.1 hectare scale in Australian vegetation compared to other continents. Vegetatio 52: 129-140.Google Scholar
  45. Sah, J. P. 1983. Nutrient content in leaf litter of dominant trees of Pulchoki hill. Thesis, Univ. Tribhuvan, Kathmandu, Nepal.Google Scholar
  46. Saxena, A. K. & Singh J. S. 1982. A phytosociological analysis of woody species in forest communities of a part of Kumaun Himalya. Vegetatio 50: 3-22.Google Scholar
  47. Shmida, A. & Wilson, M. V. 1985. Biological determinants of species diversity. J. Biogeog. 12: 1-21Google Scholar
  48. Singh J. S. & Singh S. P. 1992. Forest of Himalya Structure, functioning and impact of man. Gyanodaya Prakashan Publisher, Nainital, India.Google Scholar
  49. Slobodkin, L. B. & Sanders, H. L. 1969. On the contribution of environmental predictability to species diversity. In: Woodwell G. M. & Smith, H. H. (eds), Diversity and stability in ecological systems. Brookhaven Symp. Biol. 22: 82-95.Google Scholar
  50. Sousa, W. P. 1984. The role of disturbance in natural communities. Ann. Rev. Ecol. Syst. 15: 353-391.Google Scholar
  51. Statistical Science 1993. S-plus for Windows. Version. 3.2. Seattle, StatSci. A division of Mathsoft, Inc.Google Scholar
  52. Stevens G. C. 1992. The elevation gradient in altitudinal range: an extension of Rapoport's latitudinal rule to altitude. Amer. Nat. 140: 839-911.Google Scholar
  53. ter Braak, C. J. F. 1994. Canonical community ordination. Part I: Basic Theory and linear methods. Ecoscience 1: 127-140.Google Scholar
  54. Tilman, D. 1982. Resource competition and community structure. Princeton University Press. Princerton, N. J.Google Scholar
  55. Uprety, B. K. and Ghimire, G. P. S. 1982. Numerical analyses of forest and its relation with soil characteristics in Phulchoki Mountain, Kathmandu. J. Nat. Hist. Museum (Kathmandu) 6: 15-37.Google Scholar
  56. van der Maarel, E. 1993. Some remarks on disturbance and its relations to diversity and stability. J. Veg. Sci. 3: 733-736.Google Scholar
  57. Watt, A. 1947. Pattern and processes in the plant community. J. Ecol. 35: 1-12.Google Scholar
  58. Westhoff, V. 1971. The dynamic structure of plant communities in relation to the objectives of conservation. In: Duffey, E. & Watt, A. S. (eds), The scientific management of animal and plant communities for conservation. Symp. Brit. Ecol. Soc. 11: 3-14.Google Scholar
  59. White, P. S. 1979. Pattern, processes and natural disturbance. Bot. Rev. 45: 229-299.Google Scholar
  60. Whittaker R. H. 1965. Dominance and diversity in land plant communities. Science 147: 250-260.Google Scholar
  61. Whittaker, R. H. 1977. Evolution of species diversity in land plant communities. Evol. Biol. 10: 1-67.Google Scholar
  62. Whittaker, R. H. & Niering, W. A. 1965. Vegetation of the Santa Catalina Mountains, Arizona. A gradient analysis of the south slope. Ecology 46: 429-452.Google Scholar
  63. Whittaker, R. H. & Niering, W. A. 1975. Vegetation of the Santa Catalina Mountains, Arizona. V. Biomass, production, and diversity along the elevation gradient. Ecology 56: 771-790.Google Scholar

Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • Ole R. Vetaas
    • 1
  1. 1.Botanical InstituteBergenNorway

Personalised recommendations