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Biodiversity and Conservation

, Volume 20, Issue 12, pp 2627–2648 | Cite as

Tree diversity and conservation value of Ngovayang’s lowland forests, Cameroon

  • Christelle F. GonmadjeEmail author
  • Charles Doumenge
  • Doyle McKey
  • Gildas P. M. Tchouto
  • Terry C. H. Sunderland
  • Michael P. B. Balinga
  • Bonaventure Sonké
Original Paper

Abstract

The Ngovayang Massif of southern Cameroon is a range of small hills near the Atlantic coast, in the Lower Guinea floristic region. This region is known to harbor forests with high levels of biodiversity and endemism, but this Massif is botanically poorly known. We assessed tree species diversity, floristic composition and level of endemism of the Ngovayang forest, comparing it with other sites in Central Africa. Five 1-ha permanent plots within old-growth lowland forests of the Ngovayang Massif were censused. A total of 2,658 individuals with dbh ≥ 10 cm were recorded, belonging to 293 species, 170 genera and 60 families. The mean number of stems was 532 ± 75 stems ha−1. Taking into account other data available, the list of vascular plants known in the Massif reaches a total of 450 species. We found 47 species of high conservation value, including Cameroon endemics and other rare and threatened species. Species richness and endemism are comparable to those of the richest known sites in Central African forests. The forests of Ngovayang were found to be particularly rich in Fabaceae-Caesalpinioideae. Topographic heterogeneity, high precipitation and atmospheric humidity owing to the proximity of the ocean, and permanence of a forest cover during past geological times probably all contribute to explaining the Massif’s high tree diversity and endemism. This study highlights the botanical importance of the poorly studied Ngovayang forest within the Lower Guinea region, justifying efforts for improved assessment of this value and for the development of suitable national conservation strategies.

Keywords

1-ha permanent plots Cameroon Floristic patterns Endemic species Lower Guinea floristic region Tree alpha diversity Tropical rainforest 

Notes

Acknowledgments

We thank “Sud Expert Plantes, project#374” (SEP), a program funded by the French Ministry of Foreign Affairs, and the Centre de Cooperation Internationale en Recherche Agronomique pour le Developpement (CIRAD), for financial assistance through research grants which allowed this study. We are grateful to N. Fauvet for his technical assistance in GIS and the preparation of the maps, and to G. Walter, C. Geldenhuys, B. Sinsin and V. Freycon for valuable comments on earlier drafts of this article. We also thank two anonymous reviewers whose constructive remarks improved the manuscript. Special thanks are extended to M. Sainge, P. Mezili and J.-M. Onana for their technical expertise on specimen identification in the field and at the National Herbarium, Cameroon. We thank the people of Ngovayang for allowing us to work on their land and for assisting us in fieldwork. The authors would like to thank the Plant Biology Department of the University of Yaoundé I for their co-operation in facilitating this research.

Supplementary material

10531_2011_95_MOESM1_ESM.docx (56 kb)
Supplementary material 1 (DOCX 57 kb)

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Christelle F. Gonmadje
    • 1
    • 3
    Email author
  • Charles Doumenge
    • 2
  • Doyle McKey
    • 3
  • Gildas P. M. Tchouto
    • 4
  • Terry C. H. Sunderland
    • 5
  • Michael P. B. Balinga
    • 6
  • Bonaventure Sonké
    • 1
  1. 1.Plant Systematics and Ecology Laboratory, Higher Teacher’s Training CollegeUniversity of Yaounde IYaoundeCameroon
  2. 2.CIRADMontpellier Cedex 5France
  3. 3.Centre d’Ecologie Fonctionnelle et EvolutiveUMR, CNRS 5175Montpellier Cedex 5France
  4. 4.National Forestry SchoolMbalmayoCameroon
  5. 5.Centre for International Forestry Research (CIFOR)BOBCD, BogorIndonesia
  6. 6.Centre for International Forestry Research (CIFOR)OuagadougouBurkina Faso

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