Skip to main content

From Forest to Farmland: Species Richness Patterns of Trees and Understorey Plants along a Gradient of Forest Conversion in Southwestern Cameroon

Abstract

Vegetation surveys were carried out at 24 sampling stations distributed over four land use types, namely near-primary forest, secondary forest, agroforestry systems and annual crop lands in the northeastern part of the Korup region, Cameroon, to assess the impact of forest conversion on trees and understorey plants. Tree species richness decreased significantly with increasing level of habitat modification, being highest and almost equal in secondary and near-primary forests. Understorey plant species richness was significantly higher in annual crop lands than in other land use types. The four land use types differed in tree and understorey plant species composition, the difference being smaller among natural forests. Tree and understorey plant density differed significantly between habitat types. Density was strongly correlated with species richness, both for trees and understorey plants. Five tree and 15 understorey plant species showed significant responses to habitat. A 90% average drop in tree basal area from forest to farmland was registered. Our findings support the view that agroforestry systems with natural shade trees can serve to protect many forest species, but that especially annual crop lands could be redesigned to improve biodiversity conservation in agricultural landscapes of tropical rainforest regions.

This is a preview of subscription content, access via your institution.

References

  • Bawa K. and Seidler R. (1998). Natural forest management and the conservation of biodiversity in tropical forests. Conserv. Biol. 12: 46–55

    Article  Google Scholar 

  • Bobo K.S., Waltert M., Fichtler M. and Muehlenberg M. (2005). New bird records for the Korup Project AreaSouthwest Cameroon. Malimbus 27: 13–18

    Google Scholar 

  • Bobo K.S., Waltert M. and Muehlenberg M. (2004). On the significance of birds as bio-indicators for biodiversity studies at local spatial scales. Tag. trop. Vögel Ges. Trop. ornithol. 8: 54–65

    Google Scholar 

  • Boubli J.P., Eriksson J., Hohmann S., Wich G. and Fruth B. (2004). Mesoscale transect sampling of trees in the Lomako-Yekokora interfluviumDemocratic Republic of the Congo. Biodiv. Conserv. 13: 2399–2417

    Article  Google Scholar 

  • Boulinier T., Nichols J.D., Sauer F.R., Hines J.E. and Pollock K.H. (1998). Estimating species richness: the importance of heterogeneity in species detectability. Ecology 79: 1018–1028

    Article  Google Scholar 

  • Burnham K.P. and Overton W.S. (1978). Estimation of the size of a closed population when capture probabilities vary among animals. Biometrika 65: 625–633

    Article  Google Scholar 

  • Burnham K.P. and Overton W.S. (1979). Robust estimation of population size when capture probabilities vary among animals. Ecology 60: 927–936

    Article  Google Scholar 

  • Chao A. (1987). Estimating the population size for capture-recapture data with unequal catchability. Biometrics 43: 783–791

    Article  PubMed  CAS  Google Scholar 

  • Chazdon R.L., Colwell R.K., Denslow J.S. and Guariguata M.R. (1998). Statistical methods for estimating species richness of woody regeneration in primary and secondary rain forests of northeastern Costa Rica. In: Dallmeier, F. and Comiskey, J.A. (eds) Forest Biodiversity ResearchMonitoring and Modeling: Conceptual Background and Old World Case Studies, pp 285–309. Parthenon Publishing, Paris, France

    Google Scholar 

  • Colwell R.K. 2000. EstimateS – Statistical estimation of species richness and shared species from samples. Version 6.0b1. http:/viceroy.eeb.uconn.edu/estimates.

  • Colwell R.K. and Coddington J.A. (1994). Estimating terrestrial biodiversity through extrapolation. Philos. Trans. Roy. Soc. London, Series B 345: 101–118

    CAS  Google Scholar 

  • Cox T.F. and Cox M.A.A. (1994). Multidimensional scaling. Monographs on Statistics and Applied Probability, vol. 59. Chapman & Hall, London

    Google Scholar 

  • Davis S.D., Heywood V.H. and Hamilton A.C. (1994). Centres of Plant Diversity: A Guide and Strategy for their Conservation. Volume 1: Europe, Africa, South West Asia and the Middle East. IUCN Publications Unit, Cambridge UK

    Google Scholar 

  • Devineau J.L. (1984). Structure et Dynamique de Quelques Forêts Tropophiles de l’Ouest Africain (Côte d’Ivoire). Programme MAB Savane. Universite d’Abidjan, Abidjan, Ivory Coast

    Google Scholar 

  • Hallé F. (1990). Tropical rain forests: structure and growth dynamics relative to utilization by birds. In: Keast, A. (eds) Biogeography and Ecology of Forest Bird Communities, pp 27–33. 1990 SPB Academic Publishing bv, The HagueThe Netherlands

    Google Scholar 

  • Heltshe J.F. and Forrester N.E. (1983). Estimating species richness using the Jackknife procedure. Biometrics 39: 1–11

    Article  PubMed  CAS  Google Scholar 

  • Holm S. (1979). A simple sequentially rejective multiple test procedure. Scand. J. Stat. 6: 65–70

    Google Scholar 

  • Horváth A., March I.J. and Wolf J.H.D. (2001). Rodent Diversity and Land Use in MontebelloChiapas, Mexico. Studies on Neotropical Fauna and Environment 36: 169–176

    Article  Google Scholar 

  • Hughes J.B., Daily G.C. and Ehrlich P.R. (2002). Conservation of tropical forest birds in countryside habitats. Ecol. Lett. 5: 121–129

    Article  Google Scholar 

  • Larsen T.B. 1997. Biodiversity writ large. Korup’s butterflies, Report to Korup Project.

  • Lawton J.H., Bignell D.E., Bolton B., Bloemers G.F., Eggleton P., Hammond P.M., Hodda M., Holt R.D., Larsen T.B., Mawdsley N.A., Stork N.E., Srivastava D.S. and Watt A.D. (1998). Biodiversity inventories, indicator taxa and effects of habitat modification in tropical forest. Nature 391: 72–76

    Article  CAS  Google Scholar 

  • Magurran A.E. (1988). Ecological Diversity and its Measurement. Princeton University Press, Princeton, NJ

    Google Scholar 

  • Malaisse F. (1984). Contribution a l’étude de l’écosystème forêt dense sèche (Muhulu). Structure d’une forêt dense sèche zambezienne des environs de Lubumbashi (Zaire). Bulletin de la Société Royale de Botanique de Belgique 117: 428–458

    Google Scholar 

  • MINEF/KP 2002. A Management Plan for Korup National Park and its Peripheral Zone. 2002– 2007. WWF/EU/GTZ.

  • Nichols J.D. and Conroy M. J. (1996). Estimation of species richness. In: Wilson, D.E., Cole, F.R., Nichols, J.D., Rudran, R. and Foster, M. (eds) Measuring and Monitoring Biological Diversity. Standard Methods for Mammals, pp 226–234. Smithsonian Institution Press, Washington, DC, USA

    Google Scholar 

  • Nichols J.D., Boulinier T., Hines J.E., Pollock K.H. and Sauer J.R. (1998). Inference methods for spatial variation in species richness and community composition when not all species are detected. Conserv. Biol. 12: 1390–1398

    Article  Google Scholar 

  • Oates J.F. (1996). African Primates. Status Survey and Conservation Action Plan. Revised Edition. IUCN, Gland

    Google Scholar 

  • Olsen D.M.E., Dinerstein E.D., Wikramanayake N.D., Burgess G.V.N., Powell E.C., Underwood J.A., Itoua I., Strand H.E., Morrison J.C., Loucks C.J., Allnutt T.F., Ricketts T.H., Kura Y., Lamoreux J.F., Wettengel W.W., Hedao P., Kassem K.R. and D’Amico (2001). Terrestrial Ecoregions of the world: a new map of life on earth. Bioscience 51: 933–938

    Article  Google Scholar 

  • Rice W.R. (1989). Analyzing tables of statistical tests. Evolution 43: 223–225

    Article  Google Scholar 

  • Rodewald P.G., Dejaifve P.A. and Green A.A. (1994). The birds of Korup National Park and Korup Project AreaSouthwest ProvinceCameroon. Bird Conserv. Int. 4: 1–68

    Article  Google Scholar 

  • Rosenzweig M.L. (2003). Reconciliation ecology and the future of species diversity. Oryx 37: 194–205

    Article  Google Scholar 

  • Schulze C.H., Steffan-Dewenter I. and Tscharntke T. (2004b). Effects of land use on butterfly communities at the rain forest margin: a case study from Central Sulawesi. In: Gerold, G., Fremerey, M., and Guhardja, E. (eds) Land UseNature Conservation and the Stability of Rainforest Margins in Southeast Asia, pp 281–297. Springer-Verlag, Berlin Heidelberg

    Google Scholar 

  • Schulze C.H., Waltert M., Kessler P.J.A., Pitopang R., Veddeler M., Mühlenberg S.R., Leuschner C., Steffan-Dewenter I., Tscharntke T., Shahabuddin and Gradstein (2004a). Biodiversity indicator groups of tropical land-use systems: comparing plants, birds and insects. Ecol. Appl. 14: 1321–1333

    Google Scholar 

  • Sokpon N. (1995). Recherches ecologiques sur la forêt dense semi-decidue de Pobe au Sud du Benin: groupements vegetaux, regéneration naturelle et chute de litière. Universite libre de Bruxelles, Brussels, Belgium

    Google Scholar 

  • Sonke B. (1998). Etudes floristiques et structurales des forêts de la reserve de faune du Dja (Cameroun). Universite libre de Bruxelles, Brussels, Belgium

    Google Scholar 

  • Sonke B. and Lejoly J. (1998). Biodiversity study in Dja fauna reserve (Cameroon): using the transect method. In: Huxley, C.R., Lock, J.M. and Cutler, D.F. (eds) Chorology, Taxonomy and Ecology of the Floras of Africa and Madagascar, pp 171–179. Royal Botanic Gardens, Kew UK

    Google Scholar 

  • StatSoft. (2001). STATISTICA for Windows. StatSoft, Tulsa

    Google Scholar 

  • Turner I.M., Tan H.T.W., Wee Y.C., Ibrahim A.B., Chew P.T. and Corlett R.T. (1994). A study of plant species extinction in Singapore: lessons for the conservation of tropical biodiversity. Conserv. Biol. 8: 705–712

    Article  Google Scholar 

  • van Gemerden B.S. (2004). DisturbanceDiversity and Distributions in Central African Rain Forest. Wageningen University, The Netherlands

    Google Scholar 

  • Waltert M., Faber K., Mühlenberg M. and Lien (2002). Further declines of threatened primates in the Korup Project AreaSouth-west Cameroon. Oryx 36: 257–265

    Article  Google Scholar 

  • Waltert M., Mardiastuti A. and Mühlenberg M. (2004). Effects of land use on bird species richness in SulawesiIndonesia. Conserv. Biol. 18: 1339–1346

    Article  Google Scholar 

  • Waltert M., Bobo K.S., Sainge M.N., Fermon H. and Mühlenberg M. (2005). From forest to farmland: Habitat effects on Afrotropical forest bird diversity. Ecol. Appl. 15(4): 1351–1366

    Google Scholar 

  • White J.T.L. (1992). Vegetation History and Logging Disturbance: Effects on Rain Forest Mammals in the Lope ReserveGabon (with special emphasis on elephants and apes). University of Edinburgh, Edinburgh, UK

    Google Scholar 

  • White F. (1983). The Vegetation of Africa. UNESCO, Paris

    Google Scholar 

  • World Wildlife Fund. 2001. Terrestrial ecoregions of the world: a new map of life on earth. Published at: http://www.worldwildlife.org/wildworld/profiles/terrestrial_at.html.

  • Zapfack L., Engwald S., Sonke B., Achoundong G. and Madong B.A. (2002). The impact of land conversion on plant biodiversity in the forest zone of Cameroon. Biodiv. Conserv. 11: 2047–2061

    Article  Google Scholar 

  • Zent E.L. and Zent S. (2004). Floristic composition, structureand diversity of four forest plots in the Sierra MaigualidaVenezuelan Guayana. Biodiv. Conserv. 13(13): 2453–2483

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to K. Serge Bobo.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Bobo, K.S., Waltert, M., Sainge, N.M. et al. From Forest to Farmland: Species Richness Patterns of Trees and Understorey Plants along a Gradient of Forest Conversion in Southwestern Cameroon. Biodivers Conserv 15, 4097–4117 (2006). https://doi.org/10.1007/s10531-005-3368-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10531-005-3368-6

Key words

  • Biodiversity conservation
  • Cameroon
  • Land use
  • Reconciliation ecology
  • Trees
  • Tropical rainforest
  • Understorey plants